Recent advances in understanding non-celiac gluten sensitivity
High glycemic index of gluten-free products
“In formulating Gluten Free products, therefore, the first problem to be solved is the absence of the protein network on which to build the product. This deficiency affects the structure of the product both in terms of volume and organoleptic level. The formulations are based mainly on mixtures of starches and substances that act as “glue” and often have a strong nutritional imbalance, ie a strong fiber deficiency and a high glycemic index. The Glycemic Index clarifies how quickly the ingested carbohydrate is demolished, absorbed and released into the bloodstream as an energy source for the cells. Foods with low Glycemic Index release energy in a prolonged way, constantly and allow to avoid the feeling of hunger a few hours after a meal. Foods with high Glycemic Index release energy in the form of glucose very quickly with the result that the feeling of hunger is not slow to be felt and the excess glucose is transformed into fat storage. In the report “Glycemic Index and Gluten Free Products” by Dr. Alessandra Bosetti, clinical dietician at the Sacco hospital, the need to reconsider the characteristics of the dieto-therapeutic products to improve their glycemic index and nutritional adequacy emerge . In the various baked products there is also a series of organoleptic defects summarized here:
• Biscuits: lack of bite consistency, too hard structure or excess of sand, lack of taste persistence;
• Baked cakes: no volume, they dry quickly, gumminess, lack of taste, unbalanced nutritional profile;
• Bread, pizza: it lacks volume, it lacks elasticity in the crumb, poorly homogeneous crumb, gumminess, unbalanced nutritional profile.
In the different formulations corn flours, rice, quinoa, buckwheat are used, to which are added amides with structuring or emulsifying function and hydrocolloids. The latter have the important function of absorbing and retaining the water of the mixture and during cooking to create a gelatinized starch containment mesh. The main hydrocolloids used include guar gum, xanthan, carrageenan and hydroxymethylcellulose. To make the best use of these products, it is advisable to use hot water or long resting times that allow optimal hydration of the fibers. Still little has been studied on kneading machines: the spiral kneader the fork or the diving arms are the least suitable when there is no gluten to be formed or oriented. Normally planetary mixers are used to have the best hydration of the different components; moreover, if they allow an optimal oxidation of the dough, the mesh formed by rubbers and starches shows a better resistance and functionality. ” From: https://www.sigmasrl.com/it/blog/im purchased-del-gluten-free
Surdough fermentation (I part)
The study highlights the action of sourdough both in hydrolyzing (breaking) the proteins rich in proline (gliadin) involved in activating the human immune system both in the hydrolyser gluten (favoring digestibility) and ,above all, the high glutenins molecular weight.
Sourdough and its potential for degradation of gluten
Sourdough is produced using a culture of lactobacillus, frequently in combination with yeast. Sourdough is the oldest method for leavening bread and is still used for some applications. For example, in making bread from rye, perhaps because the dough made from rye flour needs a low pH to be appropriate for baking (Arendt et al., 2007). In comparison with yeast-treated doughs for wheat- or rye-based breads, sourdough produces a distinctively tangy or sour taste, mainly as a result of lactic acid produced by the lactobacilli. Moreover, during sourdough fermentation, proteolysis provides compounds that are precursors for the aroma volatiles and amino acids which are converted by microbes to compounds which are precursors of flavours (Gänzle et al., 2008). Traditionally sourdough is added as an ingredient to unmodified flour of wheat or rye for breadmaking. However, some authors (Rizzello et al., 2007) have proposed sourdough as the major ingredient and the only source of proteins for making gluten-free bread.
Ancient wheat species and human health: Biochemical and clinical implications
An important study that highlights the interesting characteristics of ancient varieties of wheat in relation, above all, to some widespread gastrointestinal diseases (“This manuscript reviews the nutritional value and health benefits of ancient wheats varieties, providing a summary of all in vitro, ex vivo, animal and human studies that have thus far been published.”)
Premise:
Ancient wheat species “Although there is no precise definition, it is generally accepted that ancient wheat has remained unchanged over the last hundred years. In contrast, modern species have been extensively modified and subject to cross-breeding in what is commonly referred to as the “Green Revolution”. This term was developed to refer to a set of research and technological transfer initiatives that occurred between the 1930s and the late 1960s. The Green Revolution was initiated by Strampelli, who was among the first, in Europe and in the World, to systematically apply Mendel’s laws to traits such as rust resistance, early flowering and maturity and short straw. As a consequence, Italian wheat production doubled, an achievement that during the fascist regime was referred to as the “Wheat Battle” (1925–1940) [10]. After the Second Word War, some of Strampelli’s wheat varieties were used as parents in breeding programmes in many countries in a phase of the Green Revolution, defined as Norman Borlaug’s Green Revolution. This phase was instrumental in the development of the high-yielding varieties [10]. Thereafter, during the 1960s, research was concentrated on improving the storage protein quality, thereby increasing the technological properties. Agronomists bred cultivars of maize, wheat, and rice that were generally referred to as “high-yielding varieties” based on a higher capacity for nitrogen-absorption than other varieties. High levels of nitrogen in the soils causes the lodging of wheat before harvest. Therefore, semi-dwarfing genes were bred to improve to reduce both lodging and the maturation cycle. The principle results of this revolution were the development of modern varieties characterized by higher yield, a reduced susceptibility to diseases and insects, an increased tolerance to environ- mental stresses, a homogeneous maturation (to optimize harvest) and a higher gluten content (to improve bread and pasta quality). Whilst these intensive breeding programs helped to increase production and techno- logical quality, a concomitant decrease in genetic variability as well as a gradual impoverishment of the nutritional and nutraceutical properties of the wheat occurred, mainly determined by the complete replacement of ancient local breeds with modern varieties.”
Some passages of the study help to focus the most significant evidences that, although referring to a limited number of researches, open interesting perspectives for a greater use of ancient grains in order to reduce the disorders deriving from the ingestion of gluten:
About monococcum wheat: “Compared with soft wheat, einkorn showed a lower content of both total and resistant starch (mean value: 655 vs 685 g/kg dry matter (DM) and 25.6 vs 30–88 g/kg DM respectively) [7]. However, the amount of amylose molecules, that are digested more slowly, was higher than the amount of amylopectin molecules, thereby lowering both glucose and insulin levels in the blood after meals [14] and maintaining satiety for longer periods [15]. By evaluating the average protein content, einkorn protein values were 59% higher than those of modern wheat [16], but the bread-manufacturing quality of storage proteins were poor, making it better suited to the preparation of cookies or pasta [17]. The comparative analysis of lipids and fatty acid composition in einkorn and soft wheat germ revealed a higher content of lipids (+50%) in einkorn, with a greater proportion of monounsat- urated fatty acids (+53%), and lower polyunsaturated (−8%) and saturated fatty acids (−21%) [16]. With respect to phytochemicals, einkorn showed the highest concentration of phytosterols and tocols (1054 and 57 μg/g DM respectively), but this difference was mostly marked in the HEALTHGRAIN dataset [12]. In addition, einkorn, khorasan wheat and emmer wheat cultivars showed the highest content of total carotenoids (2.26, 6.65 and 8.23 μg/g DM respectively) and lutein (7.28, 4.9 and 2.7 μg/g DM), the major carotenoid with respect to all the other species [18,19]. Of interest, several lines of einkorn showed lutein values from three to eight-fold higher than soft wheat and two-fold greater than those for durum wheat. Some authors suggested that the higher carotenoid content in einkorn-made products could be a result of lower processing losses, linked to lower lipoxygenase activity [7]. “
Although there is insufficient evidence to suggest that ancient wheat varieties prevent gluten-related disorders, several studies have shown that a diet based on less-immunoreactive wheat products, with fewer amounts and types of reactive prolamins and fructans, may help in the improvement of gastrointestinal and/or systemic symptoms of some auto-immune or chronic diseases (eg, irritable bowel syndrome, etc.) [34]. These less-immunoreactive varieties, like einkorn, may be good targets for slowing the development of disease in populations genetically predis- posed to celiac disease and other wheat sensitivities [42].
On the other hand, a subsequent paper investigating how in vitro gastro-intestinal digestion affects the immune toxic properties of gliadin from einkorn (compared to modern wheat), demonstrated that gliadin proteins of einkorn are sufficiently different from those of modern wheat, thereby determin- ing a lower immune toxicity following in vitro simulation of human digestion [40].
Although concrete functional benefits are difficult to ascertain from random individual human trials, since they are subject to differences and/or limitations in experimental design, participant number and participant characteristics in the case of parallel arm studies, results unanimously suggest that the consump- tion of products made with ancient wheat varieties ameliorate not only pro-inflammatory/anti-oxidant parameters (where investigated) but also glycaemic and lipid status. Ancient wheat species and human health: Biochemical and clinical implications. Stefano Benedettelli et altri. September 2017. (Available online at www.sciencedirect.com)
Note:
Lodging is the bending over of the stems near ground level of grain crops, which makes them very difficult to harvest, and can dramatically reduce yield.
Depeening
Ancient wheat species and human health