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Experimental test of the influence of the particle size of the bran fraction on the rheology of whole einkorn wheat doughs (Triticum monococcum)

by luciano

Experimental test by replacing fine bran with coarse bran in einkorn wheat flour

The results obtained in the present work suggest that the particle size of the fibrous fraction may represent a relevant technological parameter in the design of doughs with a weak gluten network or limited structural development capacity, as in the case of whole einkorn.

The experimental observation could also be of interest for other bread systems characterized by visco-plastic doughs, including some gluten-free systems, in which the structure of the dough depends to a greater extent on the interactions between the liquid phase and dispersed solid particles.

Analysis of results – Test no. 3 of 10-04-2026

Introduction

The present work continues a series of experimental trials dedicated to breadmaking with whole einkorn wheat flour (Triticum monococcum), a raw material that shows technological characteristics different from those of modern soft wheats and a limited gluten development capacity. Previous test (09-03-2026): Experimental application of an advanced method for the production of bread doughs with flours of limited gluten development capacity.

This characteristic is linked to the particular protein composition of einkorn, which generally presents a lower quantity of high-molecular-weight glutenin polymers and a different distribution of gliadins. Gliadins mainly contribute to the viscosity and extensibility of the dough, whereas glutenins are responsible for the formation of an elastic network capable of effectively retaining fermentation gases.

A relatively high gliadin-to-glutenin ratio therefore tends to produce doughs that are less elastic and more viscous than those obtained from modern soft wheat [Shewry & Halford, 2002; Wieser, 2007].

This technological condition is often also reflected in the empirical perception of the dough, which may appear visco-plastic, sticky and difficult to handle, with a consistency that during manual processing is sometimes described as similar to “modeling clay” (“pongo”).

In the previous test of 09-03-2026 a 600 µm sieving was adopted, with redistribution of the fractions in the biga and in the final dough.

In the current test of 10-04-2026 a significant modification was introduced in the preparation of the raw material: the flour was sieved at 500 µm and the removed bran was replaced with an equal weight of coarser bran, with particle size between 800 and 600 µm, thus reconstructing a reorganized whole flour.

The experimental hypothesis was to verify whether an einkorn dough containing a coarser bran fraction could show, compared with the previous test:

1. better dough workability

2. greater stability during proofing

3. a more open crumb structure.

Synthetic comparison between the first and the second test

Parameter

Test 09-03-2026

Test 10-04-2026

Initial flour

1800 g

1800 g

Sieve

600 µm

500 µm

Separated bran

85 g

146 g

Passing flour

1715 g

1654 g

Bran reintroduction

original bran

bran with coarser particle size (coarse bran) 800-600 µm

Final dough

1000 g

1000 g

Pre-dough (biga)

800 g

800 g

 

Materials and flour reorganization

The raw material used in the test of 10-04-2026 consists of stone-milled whole einkorn wheat flour for a total quantity of 1800 g.

The flour was entirely sieved with a 500 µm mesh, obtaining:

  • 146 g of bran fraction
  • 1654 g of passing flour

The separated bran fraction was subsequently replaced with an equal weight of coarser bran, with particle size between 800 and 600 µm, thus reconstructing 1800 g of reorganized whole flour.

The distribution of the flour in the different stages of the process was as follows:

  • Final dough: 1000 g of reorganized whole flour
  • Pre-dough (biga): 800 g of reorganized whole flour

Post-maturation operational sequence

In the previous test of 09-03-2026, after 24 hours of maturation at about 5 °C, the dough was taken out of the refrigerator and subjected to progressive warming on a warm surface at about 20 °C, covered with a silicone mat lightly greased with olive oil, with a sequence of folds and resting periods.

In that test it was observed that heat penetrated the dough mass with difficulty: after about two hours only a small part of the bottom was warmed, while the upper layers still remained cold.

This heating difficulty can also be interpreted from a physical point of view. High-hydration doughs with visco-plastic behavior indeed have low thermal diffusivity, that is, a limited capacity to transmit heat from the outside toward the inside of the mass.

In bread doughs heat transfer occurs mainly by conduction and the speed with which temperature is distributed depends on the structure of the system and on the water content. In very viscous systems molecular mobility is reduced and heat diffusion is slower than in more fluid or more porous systems [Singh & Heldman, 2014].

In the specific case of whole einkorn doughs, the combination of:

  • high dough viscosity
  • relatively weak protein structure
  • presence of the bran fraction

may contribute to slowing down heat diffusion within the mass.

In the present test some operational modifications were therefore introduced to improve thermal distribution:

  • warm surface brought to about 24 °C
  • dough slightly flattened after removal from refrigeration
  • turning of the dough every 30 minutes for about 2 hours

These modifications aim to increase the thermal exchange surface and reduce the effective thickness of the mass, promoting a more uniform distribution of temperature inside the dough.

It also emerged that at this stage it is advisable to keep the room temperature not higher than 20-21 °C, in order to avoid the premature appearance of surface ruptures.

Experimental results

Dough after cold maturation

After 24 hours at about 5 °C, the surface of the dough appears uniform, smooth and continuous, without evident signs of collapse (Photo 1).

When the dough is turned out onto the warm surface, the bottom shows a continuous structure with localized openings, due to the expansion that occurred during the transfer from the bowl to the work surface (Photo 2).

This stage does not suggest structural collapse, but rather a condition of dough relaxation. The cold slows down fermentative and biochemical processes but does not stop them completely; the dough therefore appears as a biochemically modified but mechanically relaxed system.

Prolonged dough maturation is known to progressively modify the protein structure and the enzymatic activity of the flour, improving dough extensibility and influencing the final structure of the bread [Gobbetti et al., 2014].

Critical phase after removal from refrigeration

During its stay on the warm surface, the dough goes through a phase in which the network is temporarily fragile.

The photograph immediately preceding manipulation is missing, but at that moment the dough showed moderate surface ruptures.

The available images show that, after manipulation and subsequent resting, the surface tends to compact again and become homogeneous (Photo 3). Even after about three hours in total on the warm surface, at the moment of transfer to the proofing basket, the surface once again appears continuous and regular (Photo 4).


The observed sequence can be summarized as follows:

1. removal from refrigeration with a fragile network

2. appearance of moderate surface ruptures

3. manipulation of the dough

4. resting on the warm surface

5. recompaction and reorganization of the surface

This behavior suggests that the protein network, although temporarily weakened, retains a capacity for reorganization.

The restructuring of the protein network observed is consistent with the model of formation and reorganization of the Glutenin MacroPolymer described by Wieser [Wieser, 2007].

Observations on dough workability

During manual processing, the dough containing the coarser bran appears decidedly more workable than that observed in the previous test.

To the hands the dough is:

  • less sticky
  • less viscous
  • less pasty

During manual manipulation the dough shows a plastic and weakly elastic consistency, with relatively stable deformation under the action of the hands and a limited capacity for elastic recovery.

From a biochemical point of view, this behavior is consistent with the protein composition of einkorn. The greater relative incidence of gliadins compared with glutenins indeed tends to produce doughs with predominantly plastic behavior and limited elasticity, in which deformation occurs more by viscous flow than by elastic recovery [Shewry & Halford, 2002].

The tactile perception is that of a more manageable and less adhesive mass, with an internal structure that is easier to interpret during manual processing [Dobraszczyk & Morgenstern, 2003].

Manual evaluation of the dough represents an important element in the rheological assessment of complex flour systems. Alongside instrumental tools such as the alveograph and farinograph, the baker’s manual experience makes it possible to interpret characteristics such as adhesiveness, elasticity and extensibility of the dough [Dobraszczyk & Morgenstern, 2003].

The greater workability observed in the present test can plausibly be linked to the coarser particle size of the bran fraction, which interferes less with the liquid phase of the dough and with the continuity of the protein network.

Final proofing

The dough is placed in the proofing basket only when it already appears sufficiently developed on the warm surface.

In these doughs it is in fact preferable to push proofing on the warm surface rather than in the basket, since they tend to develop more easily laterally than vertically.

The photograph of the dough at the end of proofing is particularly significant (Photo 5).

The surface shows diffuse ruptures, but the structure nevertheless continues to expand. From the moment in which the surface was still intact until the moment of the end of proofing, the dough continued to expand, rising by about 1 cm.

Despite the surface fractures, the shape of the dough remains substantially spherical, without flattening or evident lateral collapse.

This behavior suggests that the ruptures mainly affect the superficial layer of the dough, while the internal structure still maintains sufficient capacity to retain fermentation gases.

Baking, crust and final development

Baking was carried out with the same protocol as the reference test.

The bread shows orderly development, with a readable opening and well-directed growth (Photo 6).

The multiple fracture observed during baking is an intentional consequence of the method of placing the dough in the container: the dough is formed by closing the flaps without sealing them completely, subjected to slight rounding, and then placed upside down in the baking container, so that the heat naturally opens the unsealed flaps.

Crumb

The section of the bread shows a fine-medium internal structure, with alveoli distributed relatively uniformly and with some irregularities also attributable to the air incorporated during handling.

The lower part of the slice does not show a compact layer but presents alveoli also in the lower area, generally critical in weak or whole doughs (Photo 7).

Observation of the slices confirms an elastic crumb, slightly moist but not sticky, free of anomalous cavities or massively compact areas (Photos 8 and 9).

The photograph of the base of the bread shows complete baking, with superficial microfractures and the absence of compressed or collapsed areas (Photo 10).

The comparison between the bread from the first baking and that from the second baking, shaped more freely as a “ciabatta”, shows a comparable internal structure, albeit with a different expansion geometry (Photo 11).

The comparison between the section of the bread from the first test (Photo 20 but above all Photo 21) and that of the

second test (Photo 8) shows an alveolar structure that is partly different. In both cases the crumb structure is characterized by small-medium alveoli, typical of whole einkorn doughs; in the second test, however, there is a lower presence of areas with more compact crumb, particularly visible in the left area of the slice from the first test, and a greater participation of the lower part of the crumb in alveolar development.

This suggests that the particle size of the bran fraction may influence not only the viscosity of the dough and its deformability during proofing, but also the distribution of fermentative thrust within the dough mass.

In the second test, the presence of bran with a coarser particle size (coarse bran) seems to be associated with a more uniform distribution of alveoli in the crumb and with a more extensive involvement of the base of the bread in the development of the alveolar structure.

Overall, the observation suggests that a coarser bran fraction may contribute to reducing the formation of locally more compact zones in the crumb, while maintaining an overall fine but more homogeneous texture. This behavior is consistent with the hypothesis that bran particle size acts mainly on dough viscosity, on the deformability of the structure and on the mode of expansion during proofing, indirectly also influencing the distribution of alveoli in the crumb.

The comparison between the two sections also suggests a different distribution of fermentative thrust within the dough. In the second test the presence of bran with a coarser particle size seems to be associated with a more extensive participation of the lower part of the crumb in alveolar development, indicating a more uniform distribution of gas pressure in the dough mass. (I Test photos )

Physical interpretation of dough behavior

The experimental results observed in the present work can be interpreted in light of the particular protein structure of einkorn and of the interaction between the protein matrix, water and the fibrous fraction of whole flour.

Unlike modern soft wheats, einkorn generally contains a lower quantity of high-molecular-weight glutenin polymers and a different distribution of gliadins.

Gliadins mainly contribute to dough viscosity and extensibility, whereas glutenins are responsible for the formation of an elastic network capable of retaining fermentation gases.

A relatively high gliadin-to-glutenin ratio therefore tends to produce doughs that are less elastic and more viscous, with rheological behavior that can be defined as visco-plastic [Shewry & Halford, 2002; Wieser, 2007].

This characteristic is consistent with the empirical perception of the dough described during the experiment, in which the mass shows a visco-plastic consistency that during manual processing is sometimes perceived as a compact and moldable mass, similar to “pongo”.

Effect of bran particle size

One of the central aspects of the present work concerns the influence of the particle size of the bran fraction on dough behavior.

The scientific literature clearly shows that the size of bran particles significantly influences the rheological properties of whole doughs.

Very fine bran particles have a high specific surface area and tend to:

  • increase water absorption
  • increase dough viscosity
  • interfere with the continuity of the gluten network.

Coarser particles, on the contrary, interfere less with the protein structure and allow better bread expansion.

This behavior was demonstrated experimentally in the study by Noort and co-workers, which analyzed the effect of bran particle size on bread quality [Noort et al., 2010].

A similar result emerges from the systematic review by Cappelli and co-workers, which highlights how the reduction of whole flour particle size tends to increase dough viscosity and worsen its workability [Cappelli et al., 2019].

Bran and gluten structure

The role of bran in breadmaking had already been studied in the 1970s.

One of the classic works is that of Pomeranz and co-workers, who showed how the fiber present in bran can:

  • interrupt the continuity of the gluten network
  • absorb water
  • modify the rheological properties of the dough.

The effect of bran on the protein network depends significantly on the size of the particles [Pomeranz et al., 1977].

Very fine particles indeed tend to interfere more with the continuity of the protein network, whereas larger particles exert a less marked effect.

Interpretation of the behavior observed in the test

The experimental observations made during the test suggest that the coarser particle size of the bran may directly influence the overall viscosity of einkorn dough.

In einkorn the dough is already predisposed to viscous behavior because of its protein composition.

When the bran is very fine:

1. the contact surface with water increases

2. water absorption increases

3. the amount of free water in the system decreases

4. dough viscosity increases.

This phenomenon can amplify the viscous effect due to gliadins.

When, on the other hand, the bran is coarser:

  • the contact surface is smaller
  • a greater share of water remains in the continuous phase of the dough
  • the overall viscosity of the system decreases.

The result is a dough perceived as less sticky and easier to handle.

This interpretation is consistent with the manual observations made during the experiment, in which the dough containing bran with a coarser particle size (coarse bran) was easier to manage by hand and more stable during proofing.

Reorganization of the protein network

Another interesting element that emerged during the experiment concerns the capacity of the dough to recompact after the appearance of surface ruptures.

During the warming phase on the warm surface the dough showed moments in which the network appeared fragile and discontinuous, followed by subsequent recomposition of the surface.

This behavior suggests that the protein network may pass through temporary phases of discontinuity without completely losing the capacity to reorganize itself.

The restructuring of the protein network observed is consistent with the model of formation and reorganization of the Glutenin MacroPolymer described by Wieser [Wieser, 2007].

Manual evaluation of dough rheology

The tactile perception of the dough during processing represents an important element in the evaluation of the rheological properties of complex flour systems.

Alongside instrumental tools such as the alveograph and farinograph, manual evaluation by the baker makes it possible to interpret characteristics such as:

  • adhesiveness
  • elasticity
  • extensibility
  • resistance to deformation.

This aspect was highlighted in the study by Dobraszczyk and Morgenstern on the relationship between dough rheology and the breadmaking process [Dobraszczyk & Morgenstern, 2003].

In complex systems, such as whole doughs or high-hydration doughs, tactile perception can provide information that standard rheological instruments are not always able to capture.

Comparative summary table of the two tests

Parameter

Test 09-03-2026

Test 10-04-2026

Sieving

600 µm

500 µm

Reintroduced bran

original bran

bran with coarser particle size (coarse bran) 800-600 µm

Dough workability

stickier, more viscous

more workable

Behavior during proofing

more vertical development

greater lateral expansion

Dough stability

good

very good

Bread height

7-7.5 cm

5.5 cm

Dough weight

~780 g

1762 g

Weight loss

16-17 %

~22 %

Crumb structure

fine

fine-medium

Final interpretative synthesis

The set of visual observations, quantitative measurements and manual evaluations of the dough suggests that the particle size of the bran fraction may significantly influence the rheology of einkorn dough and proofing behavior.

In particular, the presence of bran with a coarser particle size appears to be associated with:

  • lower dough viscosity
  • better manual workability
  • greater stability during proofing
  • maintenance of the bread expansion capacity.

This behavior appears to be consistent with the scientific literature on bran particle size and the rheology of whole doughs [Noort et al., 2010; Cappelli et al., 2019].

Research perspectives

The results obtained in the present study indicate that the particle size of the fibrous fraction can represent a relevant technological parameter in the rheological behavior of doughs obtained from flours with limited gluten development capacity, as in the case of whole einkorn wheat.

The experimental observation according to which the use of a bran fraction with a coarser particle size is associated with a reduction in dough viscosity and with better manual workability suggests that the size of the solid particles dispersed in the system may significantly influence not only the viscosity of the system, but also the stability of the dough structure during proofing.

These results highlight the opportunity for further systematic studies on the relationship between the particle size of fibrous fractions and dough behavior, particularly in bread systems characterized by weak or only partially developed protein structures.

From this perspective, the possibility of modulating the particle size of the fibrous fraction – through the use of selected bran or other plant fibers with controlled dimensions – could represent a technological tool for regulating the rheological properties of doughs, with possible applications not only in breadmaking with ancient grains, but also in other complex bread systems, including some gluten-free doughs, in which the structure of the system depends to a greater extent on the interactions between the continuous phase and dispersed solid particles.

Overall, the results obtained suggest that the particle size of the fibrous fraction deserves greater attention as a technological variable in dough design, opening the way to further experimental studies on the role of insoluble particles in the structural dynamics of bread doughs.

Reference scientific studies

1. Effect of bran particle size on bread quality

Noort M.W.J., van Haaster D., Hemery Y., Schols H., Hamer R. (2010)

The effect of particle size of wheat bran fractions on bread quality

Journal of Cereal Science

DOI: 10.1016/j.jcs.2010.04.008

Brief abstract

The study analyzes the influence of bran particle size on the rheological properties of the dough and on bread quality. The authors separate bran into different particle-size fractions and observe that finer bran significantly increases water absorption and dough viscosity, reducing bread volume. Coarser particles interfere less with the gluten network and allow a more regular development of the bread structure.

These results are consistent with the experimental observations of the present work, in which the use of bran with a coarser particle size is associated with greater dough workability and better stability during proofing.

2. Particle size of whole wheat flour and bread quality

Cappelli A., Oliva N., Cini E. (2019)

A systematic review of the influence of whole wheat flour particle size on bread characteristics

Journal of Cereal Science

DOI: 10.1016/j.jcs.2019.102790

Brief abstract

This systematic review analyzes numerous studies on the influence of the particle size of whole flour and bran on dough properties and bread quality. The authors highlight that reducing particle size increases the specific surface area of the fiber and the water absorption capacity, resulting in increased dough viscosity and greater interference with gluten network formation. Whole flours with coarser particles instead show better workability and less interference with the protein structure.

3. Structure and function of gluten proteins

Shewry P.R., Halford N.G. (2002)

Cereal seed storage proteins: structures, properties and role in grain utilization

Biochemical Society Transactions

DOI: 10.1042/BST0300118

Brief abstract

The work analyzes the structure and function of the main cereal storage proteins, with particular attention to the role of gliadins and glutenins in the formation of the gluten network. Gliadins mainly contribute to the viscosity and extensibility of the dough, whereas glutenins are responsible for the formation of an elastic network capable of retaining fermentation gases. A high gliadin-to-glutenin ratio produces doughs that are less elastic and more viscous, a characteristic that is frequently observed in doughs obtained from einkorn.

4. Fermentation and dough maturation

Gobbetti M., De Angelis M., Di Cagno R. (2014)

Sourdough fermentation and wheat bread quality

Trends in Food Science & Technology

DOI: 10.1016/j.tifs.2014.02.012

Brief abstract

This work analyzes the role of prolonged fermentation in the biochemical modification of wheat doughs. The authors show that dough maturation involves progressive modifications of proteins and of the enzymatic activity of the flour, with effects on dough structure, its extensibility and the final quality of the bread. Prolonged fermentation may also favor the temporary relaxation of the protein network before its reorganization during processing.

Bibliography

Shewry P.R., Halford N.G. (2002)

Cereal seed storage proteins: structures, properties and role in grain utilization

Biochemical Society Transactions

DOI: 10.1042/BST0300118

Wieser H. (2007)

Chemistry of gluten proteins

Food Microbiology

DOI: 10.1016/j.fm.2006.07.004

Noort M.W.J., van Haaster D., Hemery Y., Schols H., Hamer R. (2010)

The effect of particle size of wheat bran fractions on bread quality

Journal of Cereal Science

DOI: 10.1016/j.jcs.2010.04.008

Cappelli A., Oliva N., Cini E. (2019)

A systematic review of the influence of whole wheat flour particle size on bread characteristics

Journal of Cereal Science

DOI: 10.1016/j.jcs.2019.102790

Gobbetti M., De Angelis M., Di Cagno R. (2014)

Sourdough fermentation and wheat bread quality

Trends in Food Science & Technology

DOI: 10.1016/j.tifs.2014.02.012

Dobraszczyk B.J., Morgenstern M.P. (2003)

Rheology and the breadmaking process

Journal of Cereal Science

DOI: 10.1016/S0733-5210(03)00059-6

Pomeranz Y., Shogren M.D., Finney K.F., Bechtel D.B. (1977)

Fiber in breadmaking – effects on gluten structure

Cereal Chemistry

Brandolini A., Hidalgo A. (2011)

Nutritional value of einkorn wheat

Journal of the Science of Food and Agriculture

DOI: 10.1002/jsfa.4462

Chronic low-grade inflammation: what it is and how to reduce it through diet and lifestyle

by luciano

This guide gathers practical dietary and behavioral recommendations useful for reducing the factors that may promote a state of chronic low-grade inflammation.

Chronic low-grade inflammation refers to a mild but persistent inflammatory condition of the body, often not very evident or scarcely perceived. Unlike acute inflammation — which is intense, visible, and temporary (as in the case of an infection, injury, or illness) — this form is more silent and may persist over time. In recent years, numerous studies have highlighted how this inflammatory state may contribute to the development or worsening of several metabolic and immune conditions.

Introduction

The proposed diet consists of a set of dietary guidelines and practices aimed at maintaining the intestinal microbiota in balance and promoting the best possible functioning of the immune system.

To achieve this goal, it is useful to reduce or eliminate factors that may alter the balance of the intestinal microbiota and interfere with the efficiency of the immune system.

The microbiota is naturally dynamic: a certain variability is physiological and may depend, for example, on changes in diet, lifestyle, or environment. In response to these variations, the microbiota may adapt physiologically or develop less favorable responses.

Not all variations in the microbiota are therefore negative. However, when these changes lead to persistent imbalances in the intestinal ecosystem, they may promote conditions of microbiota alteration and contribute to the onset of chronic low-grade inflammation.

Reducing this condition is therefore one of the main objectives of the pathway.

Even in the presence of ongoing diseases, adopting dietary and behavioral recommendations that help reduce chronic low-grade inflammation may contribute to preventing further worsening of the clinical condition and to promoting a better overall balance of the organism.

The diet should also be accompanied by some lifestyle guidelines, particularly regarding:
stress and anxiety management

1. regular physical activity

2. balanced lifestyle habits

This aspect is far from marginal. Numerous studies on the gut–brain axis have in fact highlighted a close bidirectional relationship between the nervous system, the intestine, and the microbiota.

Consequently, prolonged stress conditions may negatively influence intestinal balance and may partially or completely compromise the positive effects of a correct and effective diet.

Finally, but no less important, it should be remembered that the great variability of individual psychophysical conditions and the heterogeneity of responses to therapies, treatments, and dietary regimens often require careful personalization of the diet, possibly supported by one’s physician or a specialist.

It should be emphasized from the outset that:

In a truly healthy subject*, the immune system and the organs responsible for regulating homeostasis are physiologically able to maintain the state of health and defend the organism from external agents, including those of dietary origin. This balance depends on the body’s ability to appropriately modulate inflammatory responses, preserve the integrity of the intestinal barrier, and maintain effective communication between the intestine, the immune system, and the nervous system.

The method: what to avoid and why

  1. Consuming too much food: the stomach should be able to work (digest) as efficiently as possible. It is better to eat several times rather than having one large meal. The most recent scientific literature suggests that the presence of food that is not completely digested in the intestinal lumen may contribute, in specific contexts [1], to processes of chronic low-grade inflammation and to increased intestinal permeability.
    By “specific contexts” we mean the coexistence of an inefficient gastric barrier (hypochlorhydria), slowed intestinal transit (stasis), and altered intestinal permeability (leaky gut), conditions that can transform undigested food residues into pro-inflammatory stimuli for the immune system.

  2. Meals composed of many different dishes [2]: the simpler the composition of a meal, the easier gastric digestion will be. A significant presence of fats [2.1] may slow the passage of food to the intestine, prolonging digestion and potentially causing sensations of heaviness and bloating. Simple sugars are digested very quickly, usually in the small intestine. However, if they are eaten after a complete meal (perhaps rich in proteins and fiber), they remain “trapped” in the stomach [2.3] while waiting for the rest of the food to be processed and may ferment [3].

  3. Industrial food products [4]: as little as possible; they contain additives which, if consumed individually only occasionally, do not usually cause problems but, when accumulated together, may have a more or less marked pro-inflammatory action depending on the individual’s health status. In summary, it is not necessary to rigidly eliminate every food containing additives, but favoring a diet based on minimally processed foods reduces overall exposure to mixtures of additives and represents a simple, safe, and potentially beneficial strategy for intestinal and systemic health.

  4. Industrial beverages: as little as possible; they generally contain large amounts of sugar, sweeteners, and additives.

  5. Foods for people with celiac disease: as little as possible when there is no real medical necessity. Many industrial gluten-free products may contain high amounts of sugars, fats, and additives, and often have a lower fiber content than traditional products. For this reason, it is preferable to limit their consumption when not strictly necessary. It should also be remembered that the additives contained in these products, when combined, may have a pro-inflammatory effect depending on the individual’s health condition.

  6. Wine/beer: with great moderation, because alcohol may interfere with liver metabolism, increase caloric intake, and, if consumed frequently, promote inflammatory processes and alterations of intestinal balance.

  7. Spirits: avoid except in occasional situations.

  8. Coffee: yes, in amounts compatible with individual tolerance to caffeine, but with attention to the overall sugar content that may accompany it.

  9. Spices: yes, favoring those with digestive and antioxidant properties (turmeric, ginger, cinnamon, cumin) and using more irritating ones (black pepper, chili pepper) more moderately.

  10. Fried foods: in moderation because frying increases the caloric content of foods and may produce oxidized compounds and irritating substances that, if consumed frequently, may promote inflammatory processes and make digestion more difficult.

  11. Fiber: essential. Preferably 3–4 times per day. Fiber represents the main and most important source of nourishment for the microbiota: through it the microbiota produces short-chain fatty acids (butyrate, acetate, propionate) that are beneficial for intestinal health.

  12. Processed meats: sparingly, because they generally contain high amounts of salt, preservatives (nitrites and nitrates), and fats—elements which, if consumed frequently, may promote inflammatory processes and metabolic imbalances.

  13. Cheese: yes, in amounts compatible with the individual (limited if intolerant to lactose or casein). They should not be completely eliminated when well tolerated, because they represent a good source of proteins, calcium, and other micronutrients useful for the body. It is nevertheless preferable to favor simple, good-quality cheeses consumed in moderation.

  14. Sweets: in amounts compatible with the individual. If there are problems with sugars (for weight or blood glucose), they should be consumed in appropriate quantities to avoid imbalances. However, it should not be forgotten that they can also represent a compensatory source of pleasure in many situations of stress or anxiety: moderation yes, but without eliminating them completely.

  15. Gluten [5][5.1]: if possible, choose whole or semi-whole wheat pasta; bread: preferably semi-whole or whole made from durum wheat or einkorn/emmer varieties. Soft wheat contains a component of gluten that is very difficult to digest (33mer). Whenever possible, include products made with grains whose gluten is less strong and more tolerable (many ancient grains have these characteristics).

  16. Non-celiac gluten sensitivity (NCGS). This type of intolerance is “dose-dependent.” Once it has been established that a person is intolerant but not celiac, it is necessary to identify the quantity that can be tolerated without causing problems. In these cases, products made with grains whose gluten is less tenacious and more tolerable (many ancient grains have these characteristics) may help manage the issue better. It should also be emphasized that many products for people with celiac disease contain several additives: regarding this aspect, see what was stated in point 3 and note [4].

  17. Water: drink regularly during the day in adequate quantities. Water is essential for the proper functioning of metabolism, digestion, and waste elimination processes. (Doctors keep reminding us… 1.5–2 liters…)

  18. Green tea: because it contains polyphenols and antioxidant substances that may contribute to cellular protection and metabolic balance.

  19. Medications: only when truly necessary and under medical prescription.

  20. Supplements: to be used after consulting a specialist in order to define a “personalized” intake based on the existing disorder or condition. In addition, many supplements have not been sufficiently tested on large and well-characterized populations.

Specific behaviors:

  1. Engage in physical activity, even at a moderate level.

  2. If working, try to avoid situations where work leads to excessive stress.

  3. If in the post-working phase of life, engage in activities that require concentration and, if possible, creativity. Developing projects is highly beneficial for keeping cognitive functions active.

  4. Do not smoke.

  5. With your physician, define the routine general check-ups necessary for proper monitoring of your health, in addition to specific examinations for already diagnosed medical conditions.

*It is also important to clarify that the concept of a “healthy subject” does not simply coincide with the absence of clinically diagnosed diseases. In a more rigorous physiological sense, a person can be defined as truly healthy when they do not present ongoing diseases and are not in a state of chronic low-grade inflammation. This distinction is far from marginal, since in clinical practice the term “healthy” is often used in a reductive sense, coinciding only with the absence of formal diagnoses.

Notes:

[1] Undigested food

Low-grade inflammation is not caused by food itself, but by the disruption of the balance between digestion, microbiota, and the intestinal barrier. In particular:

1. Enzymatic and acid failure: If the stomach (due to stress or medications) does not break proteins down into small amino acids, long peptide chains remain that the body may mistake for threats.

2. Biochemical transformation: Undigested residues, when stagnating, undergo processes of putrefaction (proteins) or excessive fermentation (sugars), producing toxic metabolites (ammonia, phenols, gases) that irritate the intestinal mucosa.

3. The immune breach: In the presence of a “permeable” intestinal mucosa, these macromolecules and toxins cross the cellular wall and come into direct contact with the immune system, keeping it in a constant state of alert (release of inflammatory cytokines).

[2] Simplicity and enzymatic “load”

Each macronutrient (carbohydrates, proteins, fats) requires different enzymes and breakdown times. When we mix too many different foods:

  • The stomach must manage a complex chemical mixture.

  • The body struggles to optimize gastric pH for each food.

Result: A faster and “cleaner” digestion occurs when meals consist of a few well-combined ingredients.

[2.1] The role of fats

Fats are the slowest nutrients to digest. Their presence sends hormonal signals (such as cholecystokinin) that tell the stomach to slow the emptying toward the duodenum.

The positive side: They provide a prolonged sense of satiety.

The negative side: If the meal is excessively fatty, food stagnates in the stomach. This process of stagnation or fermentation is what causes the sensation of a “brick in the stomach” and abdominal bloating.

[2.3] Tips for a balanced but light meal

To avoid heaviness without giving up taste, you could follow these small precautions:

  • Prefer simple cooking methods: steaming, grilling, or baking rather than frying or prolonged sautéing.

  • Limit different protein sources: avoid mixing eggs, cheese, and meat in the same meal.

  • Add fats raw: use extra virgin olive oil at the end of cooking to preserve its properties and facilitate digestion.

In summary

The fewer “obstacles” we give our digestive system in the form of complex combinations and heavy fats, the more energy we will have available after a meal instead of feeling sleepy and bloated.

[3] Sugars

While fats slow digestion for reasons of “biochemical management” (the stomach closes the valve to take more time), simple sugars consumed at the end of a meal (here quantity plays an important role) create a sort of digestive “queue” in the stomach.

3.1. The “plug” effect and fermentation

Simple sugars are digested very quickly, usually in the small intestine. If they are consumed after a complete meal (perhaps rich in proteins and fiber), they remain “trapped” in the stomach while waiting for the rest of the food to be processed.

Consequence: In that warm and humid environment, sugars begin to ferment.

Result: Gas production, immediate abdominal bloating, and a sensation of acidity.

3.2. Fluid attraction (Osmosis)

Sugars are “osmotic” substances, meaning they attract water into the stomach and intestines in order to be diluted.

This influx of fluids can cause a sensation of abdominal distension and, in some cases, cramps or accelerated intestinal transit (not necessarily in a beneficial sense).

3.3. The impact on insulin

Unlike fats, which do not significantly stimulate insulin, a dessert at the end of a meal (again, quantity plays an important role) may cause a significant glycemic spike.

If the preceding meal was already rich in carbohydrates (pasta or bread), the dessert becomes the “last drop that makes the cup overflow.”

This spike is often followed by a crash (reactive hypoglycemia) that makes you feel tired and lacking energy shortly after eating.

Characteristic

High Fat

Sugars (Sweets)

Main action

Slow gastric emptying.

Ferment while waiting to be digested.

Sensation

Heaviness, “stone in the stomach”.

Bloating, gas in the abdomen, drowsiness.

Hormonal effect

Prolonged feeling of satiety.

Insulin spike followed by fatigue.

3.4. Fermentation in the stomach

Possible Role of Arabinoxylans in the Dynamic Model of Einkorn Dough (Analysis performed by ChatGPT)

by luciano

Introduction
This contribution analyzes the possible role of arabinoxylans in the dynamic model of einkorn dough, based on the test described in the following articles:

  1. Advanced methodology for producing bread doughs with flours having limited gluten development capacity

  2. Experimental application of the advanced methodology for the production of bread doughs with flours having limited gluten development capacity: analysis of the results. (Analysis performed by ChatGPT)

Summary of the previous articles

In these articles, the interpretation of experimental observations led to the hypothesis of a dynamic model of einkorn dough, structured in sequential phases:

dispersion → instability → reorganization → stabilization

Experimental observations showed that:

1. the protein network temporarily loses continuity after cold maturation
2. surface fractures appear during thermal reactivation
3. the dough recovers cohesion after resting and handling
4. the final bread maintains functional gas retention

This sequence suggests a non-linear and reversible behavior of the dough matrix, rather than a simple degradative process [4].

  1. Theoretical role of arabinoxylans in the dynamic model

2.1 Dispersion and competition for water

In the proposed model, arabinoxylans may already intervene in the initial dispersion phase of the biga. In this phase:

1. they absorb large quantities of water [2]
2. they increase the viscosity of the liquid phase [3]
3. they compete with gluten proteins for hydration [2]

This has two main effects:

1. temporary reduction of the continuity of the protein network [2]
2. increase in the viscosity of the system [3]

The observed phenomenon should not necessarily be interpreted as structural damage, but rather as a redistribution of water between proteins and polysaccharides [2].

2.2 Cold maturation: slow hydration of the polysaccharide matrix

During storage in the refrigerator the following may occur:

1. progressive hydration of insoluble arabinoxylans [2]
2. partial solubilization of some fractions [3]
3. increase in the viscosity of the aqueous phase [3]

This may produce a more continuous but less elastic matrix, in which:

1. the gluten network appears more relaxed [5]
2. the polysaccharide phase is more hydrated

Within the framework of the dynamic model, this phase corresponds to a biochemical relaxation of the matrix.

2.3 Post-cold storage critical window

When the dough returns to a higher temperature, the following occur simultaneously:

1. reactivation of fermentation
2. increase in gas pressure
3. variation in the viscosity of the polysaccharide matrix [3]

In this phase arabinoxylans may:

1. increase the viscous resistance of the system [3]
2. make the surface more fragile in the case of non-uniform hydration [4]

This may explain the appearance of temporary surface ruptures. From this perspective, the surface of the dough may behave like a heterogeneous viscoelastic membrane [4].

2.4 Network reorganization

During warm resting and handling:

1. the protein network may reorganize part of the disulfide bonds [5]
2. arabinoxylans may contribute to forming a continuous viscous matrix [3]

This results in a composite structure composed of:

1. protein network
2. polysaccharide matrix

This aspect is particularly relevant in cereals with weak gluten, in which dough structure is often hybrid rather than purely gluten-based [6].

“It is also plausible that a fraction of gluten proteins is not initially fully integrated into the network due to incomplete hydration or uneven water distribution within the dough matrix. During resting and handling, the progressive redistribution of water and the relaxation of the structure may allow these protein fractions to become progressively incorporated into the gluten network, contributing to the recovery of cohesion observed experimentally.”system. This mechanism may contribute to the observed recovery of cohesion.”

2.5 Final effect on the crumb

When the system is well balanced, the structure that retains gas derives from the interaction between:

1. protein network
2. viscosity of the polysaccharide phase [3]
3. gelatinized starch

Even in less balanced systems, such as in your Series II, arabinoxylans may contribute to retaining part of the gas, even in the presence of a less organized protein network. This is consistent with the observation of an irregular but stable crumb and of bread that remains functional [3].

In summary

In einkorn, dough structure can be interpreted as the result of the interaction between:

1. protein network
2. cell-wall polysaccharide matrix

In this system arabinoxylans contribute to:

1. regulation of the viscosity of the aqueous phase [3]
2. distribution of water in the dough [2]
3. stabilization of the structure [3]

In cereals with limited gluten development capacity, these polysaccharides play a complementary role in the retention of fermentation gases [3][6].

  1. Role of the polysaccharide matrix in ancient wheats

Some studies indicate that in ancient wheats such as einkorn, emmer, and spelt, dough structure does not depend exclusively on the gluten network but is also influenced to a greater extent by the non-starch matrix of the cell wall [6][7].

Compared with modern wheats, these cereals show:

1. a gluten network that is generally weaker and less continuous [6]
2. a greater relative influence of non-protein components, including arabinoxylans and other fibers [2][3]

In this context, the dough may be interpreted as less gluten-dominant and more matrix-dominant, that is, more dependent on the polysaccharide matrix and its interactions with water and proteins [3][6].

This theoretical framework is consistent with what was observed in the present study:

1. the protein network shows a temporary loss of continuity
2. the overall structure of the dough remains functional
3. a recovery of cohesion is observed after a phase of instability

Consequently, in einkorn the stability of the dough may depend not only on the initial integrity of the gluten network but also on the ability of the overall matrix to reorganize and redistribute internal stresses.

It should be specified, however, that in the present study the components of the non-starch matrix were not measured directly. Their role should therefore be considered as an interpretative hypothesis consistent with the literature, not as direct experimental evidence [2][3][6].

  1. Interpretation of the experimental results

The experimental documentation clearly highlights several points:

1. the dough network loses continuity after removal from the cold chamber
2. surface ruptures and temporary fragility appear
3. after resting and handling the mass recovers cohesion and continuity
4. the final bread shows a functional structure and effective gas retention

The observed sequence:

relaxed network → surface instability → reorganization → functional structure

is compatible with complex viscoelastic models described in the literature [4].

From a scientific perspective, this means that einkorn dough does not behave in a linearly degradative way.

The observed rupture is not necessarily an irreversible structural failure but may be part of a transient phase of matrix reorganization.

This is consistent with:

1. models of viscoelastic materials [4]
2. dynamics of gluten proteins [5]

This is one of the most interesting results of your work.

  1. Post-cold storage reorganization dynamics: original contribution of the work

The literature on ancient wheats mainly focuses on aspects such as protein composition, gluten quality, rheological parameters (alveography and farinography), and final bread volume. In this framework, einkorn is generally described as having weaker gluten, greater extensibility, and lower structural stability [6][7].

Studies that explicitly analyze the temporal dynamics of the dough network during the process, particularly in the stages following cold maturation, are relatively rare. In particular, the following aspects remain poorly documented:

1. phenomena occurring after thermal reactivation of the dough
2. evolution of the structure during resting at room temperature
3. the possibility of network reorganization following an apparent loss of continuity

To date, explicit descriptions of this sequence in einkorn appear limited; however, the observed behavior is consistent with general models of viscoelastic systems and with the known properties of the gluten network and the polysaccharide matrix.

The present study directly addresses this aspect by experimentally documenting the evolutionary sequence of the dough in the post-cold storage phase.

The photographic documentation and experimental protocol coherently highlight the following succession of states:

  1. apparently stable network at the end of cold maturation

  2. appearance of surface discontinuities during thermal reactivation

  3. progressive recovery of cohesion following resting and handling

  4. formation of a final functional structure capable of retaining fermentation gases

This sequence indicates that einkorn dough may pass through a phase of structural instability after cold storage that does not correspond to an irreversible collapse of the network but rather to a transient phase of matrix reorganization.

This result contrasts with the widespread operational interpretation according to which loss of surface continuity should be considered indicative of irreversible dough damage. On the contrary, the data suggest that this phase may represent a physiological transition of the system.

From the perspective of soft-matter physics, the observed behavior is compatible with that of complex viscoelastic systems, in which transitions may occur between states characterized by apparent rupture, relaxation, and subsequent structural reorganization, as described for doughs and other structured food systems [4][5].

In the case of einkorn, this phenomenon may be particularly evident for two main reasons:

the lower dominance of the gluten network compared with modern wheats [6]
the greater relative influence of the non-protein matrix, including polysaccharides such as arabinoxylans, on the viscosity and structure of the system [2][3]

These conditions make structural transitions less masked and therefore more observable at the macroscopic level.

In light of these observations, the present work suggests that in einkorn the final quality of the dough does not depend exclusively on the initial strength of the protein network but on the synchronization between matrix reorganization and fermentative development.

Within this framework, the post-cold storage phase emerges as a critical window of the process, in which phenomena of apparent instability may actively contribute to the construction of the final dough structure.

  1. Scientifically correct formulation

A rigorous formulation could be the following:

Experimental observations show that einkorn dough undergoes a phase of surface instability after thermal reactivation, followed by recovery of structural cohesion during resting and handling. This behavior suggests a non-linear dynamics of the dough matrix. Although in the present study the non-starch components of the cell wall were not measured directly, the observed phenomenon is consistent with models described in the literature in which matrix polysaccharides, particularly arabinoxylans, contribute to system viscosity and gas retention in cereals with limited gluten development capacity [2][3][6].

  1. Conclusions

The main conclusion of the work is that, in einkorn, temporary surface rupture does not necessarily imply failure of the network.

The network may:

break → reorganize → stabilize

if thermal and temporal conditions are appropriate [4][5].

This result is relevant because it contrasts with the widespread idea that einkorn simply collapses once network continuity is lost.

More generally, your work suggests that einkorn dough should be interpreted as a dynamic system, in which final functionality depends on the interaction between:

1. protein network
2. polysaccharide matrix
3. fermentative development
4. timing and thermal conditions of the process

Reference bibliography

[1] Izydorczyk, M. S., & Biliaderis, C. G. (1995).
Cereal arabinoxylans: Advances in structure and physicochemical properties.
Carbohydrate Polymers, 28(1), 33–48.
DOI: 10.1016/0144-8617(95)00077-1

[2] Courtin, C. M., & Delcour, J. A. (2002).
Arabinoxylans and endoxylanases in wheat flour bread-making.
Journal of Cereal Science, 35(3), 225–243.
DOI: 10.1006/jcrs.2001.0433

[3] Saulnier, L., Sado, P.-E., Branlard, G., Charmet, G., & Guillon, F. (2007).
Wheat arabinoxylans: Exploiting variation in amount and composition to develop enhanced varieties.
Journal of Cereal Science, 46(3), 261–281.
DOI: 10.1016/j.jcs.2007.06.014

[4] Dobraszczyk, B. J., & Morgenstern, M. P. (2003).
Rheology and the breadmaking process.
Journal of Cereal Science, 38(3), 229–245.
DOI: 10.1016/S0733-5210(03)00059-4

[5] Wieser, H. (2007).
Chemistry of gluten proteins.
Food Microbiology, 24(2), 115–119.
DOI: 10.1016/j.fm.2006.07.004

[6] Shewry, P. R., & Hey, S. J. (2015).
The contribution of wheat to human diet and health.
Philosophical Transactions of the Royal Society B, 370(1679), 20140271.
DOI: 10.1098/rstb.2014.0271

[7] Hidalgo, A., & Brandolini, A. (2014).
Nutritional properties of einkorn wheat (Triticum monococcum L.).
Journal of the Science of Food and Agriculture, 94(4), 601–612.
DOI: 10.1002/jsfa.6382

[8] Gebruers, K., Dornez, E., Boros, D., Fras, A., Dynkowska, W., Bedő, Z., Rakszegi, M., Delcour, J. A., & Courtin, C. M. (2008).
Variation in the content of dietary fiber and components thereof in wheats in the HEALTHGRAIN diversity screen.
Journal of Cereal Science, 48(3), 845–857.
DOI: 10.1016/j.jcs.2008.01.012

Whole Einkorn Wheat LiCoLi: Microbiology, Fermentation, and Technological Implications

by luciano

Review of the Scientific Literature on Whole Einkorn Wheat LiCoLi

Index

Part I – Microbiological and technological foundations of einkorn wheat LiCoLi

1. LiCoLi as a stable microbial ecosystem

2. The role of sourdough age

3. Microbiology of einkorn LiCoLi

4. Metabolic interactions in LiCoLi

5. Effects of fermentation on nutritional properties

6. Technological stability of mature einkorn LiCoLi

7. Technological implications for einkorn doughs

Part II – In depth analysis of mature whole einkorn wheat LiCoLi

Introduction

1. Typical microbiota of mature LiCoLi

1.1 Microbial community of LiCoLi

2. Specific microbiota of einkorn LiCoLi

3. Microbiological differences between einkorn and modern wheat

3.1 Effect of flour on the microbiome

4. Evolution of the microbiome over time

4.1 Initial dynamics

4.2 Stabilization in mature sourdoughs

5. Metabolic interactions between yeasts and bacteria

6. Technological implications of mature LiCoLi

7. Combined use of LiCoLi and baker’s yeast in bread doughs

7.1 Interaction between the two fermentative systems

7.2 Effects on fermentation dynamics

7.3 Effects on the aromatic profile

7.4 Technological effects on the dough

7.5 Practical considerations

7.6 Summary of the mixed fermentation system

Final conclusions

Related in depth study:

Proteolytic activity of whole einkorn wheat LiCoLi – lactic acid bacteria, bran enzymes and gluten protein hydrolysis. (scientific article published separately)

Abstract

Liquid Sourdough Starter (LiCoLi) obtained from einkorn wheat (Triticum monococcum) represents a complex fermentation system in which yeasts and lactic acid bacteria interact stably over time. In mature sourdoughs, maintained for years through regular refreshments, the microbial community reaches a relatively stable ecological balance with significant effects on fermentation, the aromatic profile and the technological properties of doughs. This article summarizes the available scientific knowledge on sourdough microbiology, with particular reference to whole einkorn fermentation and the phenomena observed in mature sourdough starters.

Methodological note: relationship between sourdough and LiCoLi

Most scientific studies on sourdough microbiology concern sourdough, a term used in the international literature to indicate flour and water doughs spontaneously fermented by communities of lactic acid bacteria (LAB) and yeasts.

LiCoLi (Liquid Sourdough Starter) represents a technological variant of this fermentation system characterized by high dough hydration, generally close to or above 100% relative to the weight of flour. From a microbiological point of view, LiCoLi can therefore be considered a liquid sourdough.

For this reason, many experimental findings obtained from traditional sourdoughs can also be applied to LiCoLi. However, high hydration may influence some ecological parameters of the fermentation system, including:

1. the fermentation rate

2. the diffusion of metabolites

3. the ratio between lactic acid and acetic acid

4. the growth dynamics of microbial populations.

In this article the term LiCoLi is used to indicate a liquid sourdough starter obtained from whole einkorn wheat flour, while references to the scientific literature on sourdough are considered applicable to this fermentation system due to the microbiological similarities between the two models.

1. LiCoLi as a stable microbial ecosystem

Sourdough is an ecosystem composed mainly of:

1. lactic acid bacteria (LAB)

2. osmotolerant yeasts

which live in metabolic symbiosis.

Lactic acid bacteria ferment sugars derived from starch degradation producing:

1. lactic acid

2. acetic acid

3. aromatic compounds.

Yeasts primarily produce:

1. CO₂, responsible for leavening

2. aromatic metabolites useful for flavor development.

Among the most common bacteria in mature LiCoLi are:

1. Fructilactobacillus sanfranciscensis

2. Limosilactobacillus pontis

3. Leuconostoc citreum

These microorganisms are particularly adapted to the acidic environment and to the availability of maltose typical of flour and water dough.

During fermentation several secondary metabolites are produced, including ethanol, organic acids (lactic, acetic and succinic acid), esters, aldehydes, diacetyl, acetoin and other volatile aromatic compounds that contribute to the development of the sensory profile of bread. Some lactic acid bacteria may also produce mannitol and exopolysaccharides, molecules that influence dough structure, moisture retention and the softness of the final product.

Table – Main metabolites produced in sourdough fermentation and their technological effects

Metabolite

Main microorganism

Effect on bread

Lactic acid

Lactic acid bacteria (e.g., Fructilactobacillus sanfranciscensis, Lactiplantibacillus plantarum)

Dough acidification, improved shelf life, slightly sour flavor

Acetic acid

Heterofermentative lactic acid bacteria

Sharper aroma, increased antimicrobial activity

Ethanol

Yeasts (Saccharomyces cerevisiae, Kazachstania humilis)

Precursor of aromatic compounds; evaporates during baking

CO₂

Yeasts

Responsible for dough leavening and crumb structure

Diacetyl

Lactic acid bacteria

Buttery aromatic notes

Acetoin

Lactic acid bacteria

Contribution to the aromatic bouquet of bread

Volatile esters

Yeasts and LAB

Fruity and complex aromas

Mannitol

Heterofermentative LAB

Contribution to taste and redox metabolism

Exopolysaccharides (EPS)

Some LAB (Leuconostoc, Lactobacillus)

Improves dough structure and crumb softness

Succinic acid

LAB and yeasts

Contribution to complex taste and aroma stability

2. The role of sourdough age

In sourdoughs maintained for many years the microbial community tends to stabilize. According to De Vuyst et al. (2023), continuous sourdough propagation favors the selective adaptation of specific lactic acid bacteria and yeasts, generating communities that are relatively stable over time.

Reference study

De Vuyst L., Leroy F. (2023). Sourdough production: fermentation strategies and microbial ecology

DOI: 10.1080/10408398.2021.1976100

The review highlights how the microbial communities of mature sourdoughs become highly stable thanks to ecological selection occurring during continuous refreshments.

This stability leads to:

1. more predictable fermentation

2. lower aromatic variability

3. better balance between acidity and fermentative activity.

3. Microbiology of einkorn LiCoLi

LiCoLi (Liquid Sourdough Starter) is a form of sourdough characterized by high hydration, generally equal to or greater than 100% relative to the weight of flour. From a microbiological point of view, it belongs to the category of sourdoughs, the term used in the international scientific literature to indicate doughs spontaneously fermented by communities of lactic acid bacteria (LAB) and yeasts.

The main difference between LiCoLi and solid sourdough concerns consistency and the water–flour ratio, which in LiCoLi favors greater diffusion of metabolites and a fermentative dynamic that is often faster and more homogeneous. Despite these technological differences, the two systems share a similar microbial structure and are both considered variants of traditional sourdough.

Einkorn (Triticum monococcum) has nutritional and structural characteristics different from modern wheat:

1. higher micronutrient content

2. different protein profile

3. greater presence of phenolic compounds.

Lactic fermentation of einkorn also promotes:

1. increase in mineral bioavailability

2. development of complex aromas

3. improvement of digestibility.

In the case of whole flours, the presence of bran also contributes to the introduction of greater initial microbial biodiversity and mineral compounds that may favor the development and stabilization of lactic acid bacteria and yeast communities in the sourdough starter.

Reference study

Çakır E., Arıcı M., Durak M.Z., Karasu S. (2020) Molecular and technological characterization of lactic acid bacteria in einkorn sourdough. DOI: 10.1007/s00217-020-03469-3

The study isolated 32 strains of lactic acid bacteria from spontaneous einkorn sourdough. Among the main ones:

1. Lactobacillus crustorum

2. Lactobacillus brevis

3. Lactobacillus plantarum

4. Pediococcus acidilactici

Some strains showed:

1. antifungal activity

2. phytase production (improves mineral absorption)

3. antimicrobial activity.

4. Metabolic interactions in LiCoLi

Gluten, gluten-free diet and gut microbiota

by luciano

The relationship between gluten and gut microbiota is currently the subject of growing scientific interest, especially in order to understand how a gluten-free diet may influence the balance of intestinal bacteria.

Abstract
A gluten-free diet is the main treatment for celiac disease and is increasingly widespread also among non-celiac individuals. Several studies have shown that adopting a gluten-free diet may be associated with changes in the composition of the gut microbiota, including a reduction in Bifidobacterium and Lactobacillus and an increase in Enterobacteriaceae. The most common interpretation attributes such changes to the reduction of fermentable carbohydrates present in gluten-containing cereals. However, fermentable substrates for the microbiota may also derive from many other dietary sources. Gluten is also a protein partially resistant to digestion, and its degradation may generate peptides that reach the intestine and are further metabolized by the microbiota. This article analyzes the available evidence on the relationship between a gluten-free diet and gut microbiota and discusses the still little explored hypothesis of a possible ecological role of peptides derived from incomplete gluten digestion in the intestinal microbial ecosystem.

Highlights
1 – A gluten-free diet may modify the gut microbiota.
2 – In some studies a reduction in Bifidobacterium and Lactobacillus is observed.
3 – The most common explanation is the reduction of fermentable fibers present in wheat.
4 – However, the microbiota can also obtain fibers from legumes, fruit, vegetables and resistant starch.
5 – Gluten is a protein partially resistant to digestion and some of its peptides reach the intestine.
6 – The microbiota possesses enzymes capable of degrading these peptides.
7 -The possible ecological role of gluten peptides in the microbiota is a field of research that is still little explored.

The paradox of the gluten-free diet

A gluten-free diet represents the indispensable treatment for celiac disease and is increasingly widespread also among non-celiac individuals. However, in recent years several studies have observed that adopting a gluten-free diet may be associated with changes in the composition of the gut microbiota.

In particular, some studies have reported:

  1. reduction in Bifidobacterium

  2. reduction in Lactobacillus

  3. increase in Enterobacteriaceae

These alterations have been observed not only in patients with celiac disease but also in healthy individuals who adopt a gluten-free diet.

The explanation most frequently proposed attributes such changes to the reduction of fermentable carbohydrates present in gluten-containing cereals, such as fructans and arabinoxylans.
However, this interpretation raises some questions.

The gut microbiota can in fact use fermentable fibers coming from many other dietary sources, including legumes, fruit, vegetables, seeds and resistant starch. Moreover, gluten is a protein that during digestion generates numerous peptides partially resistant to enzymatic degradation, some of which may reach the intestine and be further metabolized by the microbiota.
This raises a question that is still little explored:

is it possible that the human microbiota, especially in populations with high consumption of gluten-containing cereals, has also developed a metabolic adaptation toward peptides derived from incomplete gluten digestion?

At present there are no definitive answers, but this hypothesis represents an interesting field of research for better understanding the relationship between gluten, diet and gut microbiota.

1. Gluten-free diet and changes in the microbiota
Several studies show that adopting a gluten-free diet may be associated with changes in the gut microbiota.
In particular, the following have been observed:
1 – decrease in Bifidobacterium
2 – decrease in Lactobacillus
3 – increase in Enterobacteriaceae
These changes have been detected both in subjects with celiac disease even after years of a gluten-free diet, and in healthy individuals adopting a gluten-free diet [1][2][3].
A study conducted on healthy subjects showed that a short-term gluten-free diet is associated with:
1 – reduction in Bifidobacterium
2 – reduction in Lactobacillus
3 – increase in Escherichia coli and Enterobacteriaceae [1].
Alterations of the microbiota have also been observed in celiac patients treated with a gluten-free diet, suggesting that normalization of the microbiota does not always occur completely despite clinical remission of the disease [2][4].
Some studies report that 60–80% of celiac patients still show intestinal dysbiosis despite a correct gluten-free diet. Probiotics and dietary modifications can modulate the microbiota in celiac patients, but no therapy has yet demonstrated that it can stably correct dysbiosis

2. The most common interpretation: reduction of fermentable carbohydrates
The explanation most frequently proposed is that a gluten-free diet entails a reduction of fermentable complex carbohydrates, with a consequent decrease in the substrates available for beneficial intestinal bacteria. By eliminating cereals such as wheat, rye and barley, the intake of some components of the wheat food matrix is in fact reduced, including:
1 – fructans
2 – arabinoxylans
3 – some fermentable fibers
These compounds are important substrates for the gut microbiota and contribute to the production of beneficial metabolites such as short-chain fatty acids [5][6].
According to this interpretation, therefore, the alterations observed in the microbiota would be mainly due to the modification of the food matrix and the intake of fermentable fibers, rather than to the absence of gluten itself [5].

3. A critical point: fibers can come from many other sources
However, fermentable substrates for the microbiota can come from many other dietary sources, including:
1 – legumes
2 – fruit
3 – vegetables
4 – seeds
5 – tubers
6 – rice
7 -resistant starch
Numerous studies indicate that the following are particularly important for microbiota health:
1 – fermentable fibers
2 – complex plant polysaccharides
3 – resistant starch
components that do not depend exclusively on wheat consumption.
Therefore, claiming that the wheat food matrix is indispensable for maintaining intestinal eubiosis is not supported by definitive evidence.

4. What happens to gluten during digestion
Gluten is a complex protein composed mainly of:
1 – gliadins
2 – glutenins
During gastrointestinal digestion some protein sequences are particularly resistant to enzymatic hydrolysis. This happens because gluten contains sequences rich in proline and glutamine, which make complete degradation by human digestive enzymes difficult [7][8].
Consequently, some peptides derived from gluten digestion may reach the small intestine and the colon in the form of partially digested protein fragments.

5. The role of the microbiota in gluten degradation
Several intestinal bacteria possess enzymes capable of further degrading peptides derived from gluten.
Among the most studied genera are:
1 – Lactobacillus
2 – Bifidobacterium
3 – Bacteroides
4 – some species of Clostridium
These microorganisms possess microbial peptidases capable of degrading proline-rich sequences present in gluten peptides [9][10].
Some studies also suggest that specific strains of Bifidobacterium and Lactobacillus may reduce the formation of toxic gliadin peptides and modulate the immune response associated with gluten [11].

6. Bioactive peptides derived from gluten
A further little explored aspect concerns the possibility that microbial degradation of gluten produces peptides with biological activity. Proteomic analyses have shown that gluten digestion generates numerous peptide fragments with potential biological and immunological activity [7][12].
Enzymatic digestion of food proteins can in fact generate bioactive peptide fragments with different biological functions, including:
1 – modulation of inflammation
2 – protection of the intestinal mucosa
3 – antimicrobial activity.
Among these, the following have been described, for example:
1 – the peptide ω-gliadin ω(105-123) from einkorn, which in in vitro studies showed protective effects on the intestinal mucosa
2 – the peptide p10mer (QQPQDAVQPF) identified in some wheat varieties
These results suggest that gluten degradation could generate biologically active peptides. The physiological role of many of these peptides in humans remains still poorly clarified and represents an emerging field of research.

7. The central role of short-chain fatty acids
The gut microbiota performs numerous important metabolic functions, including the production of short-chain fatty acids (SCFAs):
1 – butyrate
2 – propionate
3 – acetate
These metabolites derive mainly from the fermentation of dietary fibers and perform fundamental functions:
1 – nourishment of intestinal epithelial cells
2 – strengthening of the mucosal barrier
3 – modulation of the immune system
4 – reduction of intestinal inflammatory processes.
For this reason, the intake of fermentable fibers is considered one of the most important dietary factors for maintaining the balance of the microbiota [6].

In-depth section
Can undigested gluten have an ecological role in the microbiota?