Prebiotic wheat bread: Technological, sensorial and nutritional perspectives and challenges

Gut Microbiota Fermentation of Digested Almond-Psyllium-Flax Seed-Based Artisan Bread Promotes Mediterranean Diet-Resembling Microbial Community

Different modifications of the standard bread recipe have been proposed to improve its nutritional and health benefits. Here, we utilized the in vitro Human Gut Simulator (HGS) to assess the fermentation of one such artisan bread by human gut microbiota. Dried and milled bread, composed of almond flour, psyllium husks, and flax seeds as its three main ingredients, was first subjected to an in vitro protocol designed to mimic human oro-gastro-intestinal digestion. The bread digest was then supplied to complex human gut microbial communities, replacing the typical Western diet-based medium (WM) of the GHS system. Switching the medium from WM to bread digest resulted in statistically significant alterations in the community structure, encoded functions, produced short-chain fatty acids, and available antioxidants. The abundances of dietary fiber degraders Enterocloster, Mitsuokella, and Prevotella increased; levels of Gemmiger, Faecalibacterium, and Blautia decreased. These community alterations resembled the previously revealed differences in the distal gut microbiota of healthy human subjects consuming typical Mediterranean vs. Western-pattern diets. Therefore, the consumption of bread high in dietary fiber and unsaturated fatty acids might recapitulate the beneficial effects of the Mediterranean diet on the gut microbiota.

Gluten-free Nan-e-Fasaee: Formulation optimization on the basis of quinoa flour and inulin

Diversification of gluten-free (GF) bakery products is considerably important, as those who suffer from gluten intolerance should follow a GF diet their whole life. Regarding this study, it was aimed at optimizing the formulation of a quinoa-based GF traditional bakery product, i.e. Nan-e-Fasaee using inulin as a bifunctional agent (both a prebiotic compound and a structure-forming agent). Otherwise, its potential role as a fat and sugar replacer was also assessed. For this purpose, short (S)- and long (L)-chain inulin were used as sugar and fat replacers, respectively, at 0%-50% w/w in quinoa flour (QF)-based GF Nan-e-Fasaee and optimization was done based on rheological, textural, and sensory analysis. Results indicated that QF diet provided the batter with the dominance of elastic modulus and increased hardness (i.e. 5170.0 ± 22.50 g in the presence of QF compared to 1477.0 ± 20.81 g in wheat-based ones). Inulin inclusion reduced the hardness, as the lowest was observed at S-inulin substitution levels of 40% and 50% w/w, with values equal to 2422.0 ± 20.81 and 2431.0 ± 35.57 g, respectively (the most similar ones to control sample). The interference of S-inulin with the non-gelatinized starch structure is supposed to decrease the hardness. The highest score in texture was also perceived at F6 and F13, with values equal to 8.00 ± 0.10 and 7.97 ± 0.05, respectively. Using S- and L-inulin in combination is found to improve the textural characteristics due to preventing the competitive role of sugar in water absorption in formulations containing L-inulin. Regarding optimization of quinoa-based GF Nan-e-Fasaee with reduced sugar and fat levels using inulin, it is found to be feasible.

Formulation optimization of functional wheat bread with low glycemic index from technological and nutritional perspective

Inclusion of prebiotic compounds as indigestible dietary fiber in wheat bread has grown rapidly considering the increased public awareness about their impact on health. However, through their incorporation, the technological characteristics may adversely be influenced by gluten dilution impacts. This study was done to evaluate the impacts of long chain, native and short chain inulin (L-, N-, and S-type inulin, respectively) at 8%, 10%, 12%, 14%, and 16% w/w as Inulin Reconstituted Wheat Flour (IRWF) with similar gluten: carbohydrate ratio of wheat flour (at 10%, 12.5%, 15%, 17.5%, 20% w/w) on technological and nutritional value of wheat bread. Results indicated that despite no gluten dilution induced by IRWF supplementation, technological characteristics were adversely influenced especially at higher substitution level of L-type-containing formulations which is attributed to their higher water absorption index (WAI). Reversely, the nutritional value was positively influenced in which the lowest hydrolysis index (26.64%); predicted Glycemic Index (51.93%) and fructan loss content (25.42%) were found at L-type inulin-containing IRWF at the highest substitution level (20% w/w). As the nutritional value of wheat bread as staple foodstuff is important, optimizing the bread-making process to decrease all reverse impacts induced by L-inulin-type inclusion seems to be required.

Nutritional, antioxidant, carbohydrate hydrolyzing enzyme inhibitory activities, and glyceamic index of wheat bread as influence by bambara groundnut substitution

The research was designed to ascertain the potential of bambara groundnut inclusion in wheat bread to improve antioxidant activity, modulate carbohydrate hydrolyzing enzyme activities, and lower glyceamic index/ load. Protein (g/100 g) (11.2—11.73) and energy value (kcal/100 g) (421.5—435.5) of the bread were significantly higher than commercial wheat flour bread (CWF—10.45; 388.7). However, developed experimental bread samples exhibited higher growth performance in rats, free radical scavenging potentials, inhibitory activities against carbohydrate hydrolyzing enzymes and low glycemic index than other bread samples. Nevertheless, experimental bread samples were rated lower compared with the controls samples as regards organoleptic properties. The study authenticates that WBO3—25% wheat, and 75% bamabara groundnut WBO3 exhibits higher potentials as regards nutritional composition, growth indices, free radical scavenging potentials, ability to modulate carbohydrate hydrolyzing enzyme and lower glycemic index/ load. Hence, WBO3 may be recommended as functional bread for hyperglycemia prevention/ management.

Technological characteristics of inulin enriched gluten-free bread: Effect of acorn flour replacement and fermentation type

Textural, physicochemical, and sensory characteristics of rice-based gluten-free bread in the presence of acorn flour; inulin and different fermentation type (yeast starter fermentation [Y] or mixed fermentation based on sourdough [MF-SD]) were investigated. Acorn flour was added to replace rice flour at a proportion of 10, 30, and 50% W/W. Furthermore, the mixture flour was replaced by inulin as a functional prebiotic ingredient at 10% W/W. Considering results obtained at this study, using mixed fermentation based on sourdough and inulin at 10% W/W provide the structure able to restore gases through baking process at formulations containing acorn flour at 30% W/W (A30R70SL). The highest specific volume (1.47 ± 0.04 cm3 g-1) and the lowest hardness (40.97 ± 0.87 N) are observed in A30R70SL which seems to be induced by its potential to form gel. Acorn flour substitution level at 50% W/W adversely influenced the technological characteristics of final product and its perception by the consumer. Acorn flour substitution up to 30% W/W is preferred by the consumer which is attributed to its potential role to improve the unpleasant pale color of rice-based gluten-free products. A negatively significant correlation has been observed between the color perception by the consumer and crumb lightness (r = -.493, p ≤ .05).