Hydrocolloids and Food Emulsifiers II part

C – Hydrocolloids also modulate gut microbiota, offering various health benefits. Certain hydrocolloids, such as inulin and pectin, act as prebiotics, promoting beneficial gut bacteria growth and influencing microbiota composition and diversity (Bouillon et al., 2022; Gularte & Rosell, 2011).

D – Hydrocolloids are long-chain hydrophilic polymers used in food systems for thickening, gelling, and stabilization. They significantly influence starch retrogradation, hydrolysis, and modulation of the gut microbiota, with both positive and negative effects. These effects depend on factors such as the type of hydrocolloid, its concentration, interactions with starch, and environmental conditions such as temperature and processing methods. Some hydrocolloids inhibit starch retrogradation by interrupting amylose recrystallization, while others promote it under certain conditions. They can also alter starch hydrolysis by modifying the accessibility of enzymes to starch granules, slowing or accelerating digestion. Furthermore, hydrocolloids act as fermentable fibers, promoting the growth of beneficial gut bacteria, which can influence metabolic processes. Despite significant advances, the complexity of these interactions remains incomplete, as the effects vary depending on the composition of the individual microbiota. This review explores the mechanisms by which hydrocolloids modulate starch behaviors and the gut microbiota, synthesizing the current literature and identifying future research directions to address existing knowledge gaps.
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In food systems, hydrocolloids influence starch retrogradation, starch hydrolysis, and gut microbiota modulation, essential factors for both food quality and human health.
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Several hydrocolloids, including xanthan gum, pectin, β-glucan, and konjac glucomannan, influence starch hydrolysis and reduce its digestibility. Their effects depend on their molecular structure, source, concentration, interactions with starch, and processing conditions (Ma et al., 2024). By increasing the viscosity of starch-based matrices, hydrocolloids create a resistant gel network, slowing the enzymatic degradation of starch in the gastrointestinal tract. This delayed hydrolysis results in a controlled glucose release and a lower postprandial glycemic response (Bae & Lee, 2018; Bellanco et al., 2024). Consequently, hydrocolloids have the potential to improve glycemic control and reduce the risk of metabolic disorders such as type 2 diabetes. Yassin et al. (2022) reported that incorporating xanthan gum, lambda-carrageenan, or psyllium husk (1–5% w/w of flour weight) into white bread significantly reduced glycemic potency, with psyllium husk at 5% w/w exerting the strongest effect. Similarly, Mæhre et al. (2021) found that white bread fortified with guar gum reduced postprandial glycemic responses.
Hydrocolloids also modulate the gut microbiota, offering several health benefits. Some hydrocolloids, such as inulin and pectin, act as prebiotics, promoting the growth of beneficial gut bacteria and influencing the composition and diversity of the microbiota (Bouillon et al., 2022; Gularte & Rosell, 2011). Their prebiotic effects depend on their physicochemical properties, with variations in polymeric structure and source influencing gut health outcomes (Ağagündüz et al., 2023). Reported benefits include improved digestion, enhanced immune function, and reduced inflammation, although the extent and mechanisms of these effects remain inconsistent in the literature (Zhang et al., 2023). Further research is needed to fully understand both the benefits and potential limitations of hydrocolloid applications for gut health. This review provides an in-depth analysis of the effects of hydrocolloids on starch retrogradation, digestibility, and the gut microbiota, addressing both positive and negative findings, and aims to inform the development of functional foods with improved health benefits. The multifunctional role of hydrocolloids in modulating retrogradation, starch hydrolysis, and the gut microbiota. Xikun Lu et al. Food Chemistry
Volume 489, 15 October 2025, 144974.

In depth analysis
Hydrocolloids are a diverse group of hydrophilic long-chain polymers, primarily polysaccharides and certain proteins, known for their gelling, thickening, and stabilizing properties in various industries, particularly food production (Cevoli et al., 2013). Their ability to disperse in water is attributed to numerous hydroxyl (–OH) groups, which enhance interactions in aqueous environments. Hydrocolloids are classified based on their sources, structural characteristics (linear or branched), charge properties (neutral, negative, or positive), and functional roles such as gelling, thickening, and adhesion (Kraithong, Theppawong, et al., 2023). Beyond food applications, they are widely used in pharmaceuticals, cosmetics, coatings, and packaging, contributing to rheological and structural modifications (Pegg, 2012). In food systems, hydrocolloids influence starch retrogradation, starch hydrolysis, and gut microbiota modulation, which are critical for both food quality and human health. Retrograded starch, or resistant starch type 3 (RS3), forms through the recrystallization of gelatinized starch, creating a structured crystalline network (Han et al., 2024). RS3 formation is primarily influenced by amylose content, as amylose rearranges more readily than amylopectin, and by water content, with optimal recrystallization occurring between 20 and 90 % moisture (Han et al., 2024). Lipids and proteins also impact starch retrogradation, as lipid-amylose complexes limit amylose availability for crystallization, while proteins influence water distribution and create physical barriers that hinder retrogradation (Liu et al., 2024). Hydrocolloids modify RS3 formation by altering starch structure and water interactions. Galactomannans such as guar gum, tara gum, locust bean gum, and konjac glucomannan enhance short-term retrogradation, typically within one day, by increasing amylose concentration in the continuous phase (Funami et al., 2005; Funami et al., 2008). However, these hydrocolloids may also reduce the gelled fraction of amylose by decreasing amylose leaching during gelatinization. Additionally, they may inhibit long-term retrogradation by preventing amylose crystallization and its co-crystallization with amylopectin while enhancing water retention within the starch matrix. Controlling water mobility and distribution is crucial in mitigating starch retrogradation. (Funami et al. 2005). The multifunctional role of hydrocolloids in modulating retrogradation, starch hydrolysis, and the gut microbiota. Xikun Lu et al. Food Chemistry Volume 489, 15 October 2025, 144974.

E – Carrageenan (CGN).
Carrageenan (CGN) is a high molecular weight polysaccharide extracted from red algae, composed of D-galactose residues linked by β-1,4 and α-1,3 galactose-galactose bonds. It is widely used as a food additive in processed foods for its thickening, gelling, emulsifying, and stabilizing properties. In recent years, with the spread of the Western diet (WD), its consumption has increased. However, there is ongoing debate about its safety. CGN is widely used as an inflammatory agent and adjuvant in vitro and in experimental animal models to study immune processes. Carrageenan (CGN) is implicated in the pathogenesis and clinical management of inflammatory bowel disease (IBD); food exclusion diets may, in fact, represent a therapy or to evaluate the activity of anti-inflammatory drugs. CGN can activate the α-Gal pathways commonly known as the “α-Gal syndrome.” This review aims to discuss the role of innate immune responses in inflammation, altering the composition of the gut microbiota, and the thickness of the mucosal barrier. Clinical evidence suggests that it is effective for disease remission. Furthermore, the presence of specific IgE for the α-Gal oligosaccharide has been associated with allergic reactions to carrageenan in inflammatory bowel disease and allergic reactions, according to current evidence. Furthermore, since definitive data on the safety and effects of CGN are not available, we suggest filling some gaps and recommend limiting human exposure to CGN by reducing consumption of ultra-processed food. The Role of Carrageenan in Inflammatory Bowel Diseases and Allergic Reactions: Where Do We Stand? Barbara Borsani et al. Nutrients 2021, 13, 3402. https://doi.org/10.3390/nu13103402.

F- Xanthan gum showed various positive effects on metabolism. Furthermore, xanthan gum is fermented by bacteria to produce SCFAs (Bourquin et al., 1996), and consumption of the food additive xanthan gum affected gut microbiome (Ostrowski et al., 2022).

G – While xanthan gum is generally considered safe, some individuals may experience allergic reactions. These reactions can range from mild to severe, and symptoms may include skin rashes, digestive issues, or respiratory problems. People with known allergies to wheat, corn, soy, or dairy may be more susceptible, as xanthan gum is often produced from these sources.
Here’s a more detailed breakdown:
What is Xanthan Gum?
Xanthan gum is a polysaccharide produced by fermenting the bacterium Xanthomonas campestris. It’s a common food additive used as a thickener, stabilizer, and emulsifier.
Potential Allergic Reactions:
Some individuals may experience allergic reactions to xanthan gum, even though it’s generally considered safe. These reactions are due to the body’s immune system mistakenly identifying xanthan gum as a harmful substance and producing IgE antibodies, which trigger histamine release.
Symptoms:
Allergic reactions can manifest in various ways, including:
Skin reactions like hives, rashes, or itching.
Gastrointestinal issues such as bloating, gas, or diarrhea.
Respiratory symptoms like sneezing, runny nose, or difficulty breathing.
Other symptoms like headaches, itchy or watery eyes, and scratchy throat.
Who is at Risk?
Individuals with known allergies to wheat, corn, soy, or dairy may be more likely to react to xanthan gum, as it’s often produced using these ingredients. Premature infants may also be at risk of complications from xanthan gum, particularly in formula or breast milk thickeners.
Testing:
Allergy tests, including IgE blood tests, can be used to detect xanthan gum allergies.

H – Hydrocolloids, while beneficial in many ways for gut health, also have limitations. They can potentially hinder nutrient absorption by forming a viscous barrier that slows down the release and diffusion of nutrients, digestive enzymes, and bile salts. Furthermore, the specific mechanisms of how hydrocolloids interact with the gut microbiome and the long-term health effects are not fully understood, which limits their widespread application, particularly in functional foods like yogurt.

Here’s a more detailed breakdown:
1. Hindered Nutrient Absorption:
Hydrocolloids can create a gel-like layer on the intestinal surface, which can physically block the contact between nutrients and the intestinal lining.
This barrier effect can reduce the rate at which nutrients, including those from supplements or fortified foods, are absorbed.
The increased viscosity caused by hydrocolloids can also slow down the diffusion of digestive enzymes and bile salts, further impacting nutrient digestion and absorption.
2. Microbiome Interactions:
Hydrocolloids can impact the composition and activity of the gut microbiome, sometimes leading to shifts in the balance of beneficial and harmful bacteria.
The effects on the microbiome are complex and depend on various factors, including the specific type of hydrocolloid, its concentration, and the individual’s gut microbiome composition.
While some hydrocolloids may act as prebiotics, promoting the growth of beneficia bacteria, others might have less desirable effects or their effects could vary greatly.
3. Limited Understanding of Mechanisms:
The precise mechanisms by which hydrocolloids influence gut health and nutrient absorption are not fully elucidated.
More research is needed to understand how different hydrocolloids interact with the gut and how they affect digestion, nutrient absorption, and the gut microbiome.
4. Variability in Effects:
The effects of hydrocolloids on gut health can vary depending on several factors, including the type of hydrocolloid, its molecular structure, concentration, and the specific conditions in the digestive tract.
For example, some hydrocolloids may promote resistant starch formation and reduce starch digestibility, while others may have the opposite effect under certain conditions.
5. Potential for Negative Effects:
While generally considered safe, some hydrocolloids, like carrageenan, have faced scrutiny due to potential inflammatory effects or the generation of pro-inflammatory oligosaccharides by gut bacteria.
It’s crucial to consider the potential for adverse effects and to choose hydrocolloids carefully, especially when developing functional foods or supplements.
In summary, while hydrocolloids offer promising avenues for improving gut health and developing functional foods, it’s essential to acknowledge their potential limitations and to conduct further research to fully understand their effects and optimize their application in various contexts.