The acute impact of the intake of four types of bread on satiety and blood concentrations of glucose, insulin, free fatty acids, triglyceride and acylated ghrelin. A randomized controlled cross-over trial

Breadmaking Performance of Elite Einkorn (Triticum monococcum L. subsp. monococcum) Lines: Evaluation of Flour, Dough and Bread Characteristics

Einkorn flour, rich in proteins, carotenoids, and other antioxidants, generally has poor breadmaking value. In this research, the composition and technological characteristics of the flours and breads of two elite einkorns (Monlis and ID331) and a bread wheat (Blasco), cropped in four different environments, were evaluated. The einkorns confirmed better flour composition than bread wheat for proteins (on average, 16.5 vs. 10.5 g/100 g), soluble pentosans (1.03 vs. 0.85 g/100 g), and yellow pigment (10.0 vs. 1.0 mg/kg). Technologically, they had better SDS sedimentation values (89 vs. 66 mL), lower farinographic water absorption (52.6 vs. 58.8%), and a similar development time, stability, and degree of softening. Viscoelasticity tests showed lower storage and loss moduli and more prevalent elastic behaviour for Blasco, while rheofermentographic tests showed an anticipated development time (120.8 vs. 175.0 min), higher maximum height (73.0 vs. 63.0 mm), and superior retention coefficient (99.1 vs. 88.7%), but a lower CO₂ total (1152 vs. 1713 mL) for einkorn doughs. Einkorn breads were bigger than the control (736 vs. 671 cm³); crumb pores percentage was similar, but medium-size pores were scarcer. Finally, a 52-h shelf-life trial demonstrated that einkorn bread had a softer texture, maintained for a longer time, and a slower retrogradation than the control. Therefore, choice of appropriate varieties and process optimisation allows the production of excellent einkorn breads with a superior nutritional value and longer shelf life.

Metabolic Profile of Einkorn, Spelt, Emmer Ancient Wheat Species Sourdough Fermented with Strain of Lactiplantibacillus plantarum ATCC 8014

The continuous development of bakery products as well as the increased demands from consumers transform ancient grains into alternatives with high nutritional potential for modern wheat species. The present study, therefore, follows the changes that occur in the sourdough obtained from these vegetable matrices fermented by Lactiplantibacillus plantarum ATCC 8014 during a 24 h. period. The samples were analyzed in terms of cell growth dynamics, carbohydrate content, crude cellulose, minerals, organic acids, volatile compounds, and rheological properties. The results revealed significant microbial growth in all samples, with an average value of 9 log cfu/g but also a high accumulation of organic acids with the increase in the fermentation period. Lactic acid content ranged from 2.89 to 6.65 mg/g, while acetic acid recorded values between 0.51 and 1.1 mg/g. Regarding the content of simple sugars, maltose was converted into glucose, and fructose was used as an electron acceptor or carbon source. Cellulose content decreased as a result of the solubilization of soluble fibers into insoluble fibers under enzymatic action, with percentages of 3.8 to 9.5%. All sourdough samples had a high content of minerals; the highest of which-Ca (246 mg/kg), Zn (36 mg/kg), Mn (46 mg/kg), and Fe (19 mg/kg)-were recorded in the einkorn sourdough.

Nutritional benefits of sourdoughs: A systematic review

Food fermentation using sourdough-i.e., consortia of lactic bacteria and yeasts-is increasingly considered among the public as a natural transformation yielding nutritional benefits; however, it is unclear whether its alleged properties are validated by science. The aim of this study was to systematically review the clinical evidence related to the effect of sourdough bread on health. Bibliographic searches were performed in 2 different databases (The Lens and PubMed) up to February 2022. Eligible studies were randomized controlled trials involving adults, healthy or not, given any type of sourdough bread compared with those given any type of yeast bread. A total of 573 articles were retrieved and investigated, of which 25 clinical trials met the inclusion criteria. The 25 clinical trials included a total of 542 individuals. The main outcomes investigated in the retrieved studies were glucose response (N = 15), appetite (N = 3), gastrointestinal markers (N = 5), and cardiovascular markers (N = 2). Overall, it is currently difficult to establish a clear consensus with regards to the beneficial effects of sourdough per se on health when compared with other types of bread because a variety of factors, such as the microbial composition of sourdough, fermentation parameters, cereals, and flour types potentially influence the nutritional properties of bread. Nonetheless, in studies using specific strains and fermentation conditions, significant improvements were observed in parameters related to glycemic response, satiety, or gastrointestinal comfort after bread ingestion. The reviewed data suggest that sourdough has great potential to produce a variety of functional foods; however, its complex and dynamic ecosystem requires further standardization to conclude its clinical health benefits.

The role of cereal soluble fiber in the beneficial modulation of glycometabolic gastrointestinal hormones

According to cohort studies, cereal fiber, and whole-grain products might decrease risk for type 2 diabetes (T2DM), inflammatory processes, cancer, and cardiovascular diseases. These associations, mainly affect insoluble, but not soluble cereal fiber. In intervention studies, soluble fiber elicit anti-hyperglycemic and anti-inflammatory short-term effects, partially explained by fermentation to short-chain fatty acids, which acutely counteract insulin resistance and inflammation. ß-glucans lower cholesterol levels and possibly reduce liver fat. Long-term benefits are not yet shown, maybe caused by T2DM heterogeneity, as insulin resistance and fatty liver disease - the glycometabolic points of action of soluble cereal fiber - are not present in every patient. Thus, only some patients might be susceptive to fiber. Also, incretin action in response to fiber could be a relevant factor for variable effects. Thus, this review aims to summarize the current knowledge from human studies on the impact of soluble cereal fiber on glycometabolic gastrointestinal hormones. Effects on GLP-1 appear to be highly contradictory, while these fibers might lower GIP and ghrelin, and increase PYY and CCK. Even though previous results of specific trials support a glycometabolic benefit of soluble fiber, larger acute, and long-term mechanistic studies are needed in order to corroborate the results.

Effect of metformin on nonalcoholic fatty liver based on meta-analysis and network pharmacology

BACKGROUND

Whether metformin is related to nonalcoholic fatty liver disease (NAFLD) is controversial. Our aim was to investigate the relationship between metformin and NAFLD that may predict the metformin potential of these lesions and new prevention strategies in NAFLD patients.

METHODS

The meta-analysis was analyzed by Revman 5.3 softwares systematically searched for works published through July 29, 2022. Network pharmacology research based on databases, Cytoscape 3.7.1 software and R software respectively.

RESULTS

The following variables were associated with metformin in NAFLD patients: decreased of alanine aminotransferase (ALT) level (mean difference [MD] = -10.84, 95% confidence interval [CI] = -21.85 to 0.16, P = .05); decreased of aspartate amino transferase (AST) level (MD = -4.82, 95% CI = -9.33 to -0.30, P = .04); decreased of triglyceride (TG) level (MD = -0.17, 95% CI = -0.26 to -0.08, P = .0002); decreased of total cholesterol (TC) level (MD = -0.29, 95% CI = -0.47 to -0.10, P = .003); decreased of insulin resistance (IR) level (MD = -0.42, 95% CI = -0.82 to -0.02, P = .04). In addition, body mass index (BMI) (MD = -0.65, 95% CI = -1.46 to 0.16, P = .12) had no association with metformin in NAFLD patients. 181 metformin targets and 868 NAFLD disease targets were interaction analyzed, 15 core targets of metformin for the treatment of NAFLD were obtained. The effect of metformin on NAFLD mainly related to cytoplasm and protein binding, NAFLD, hepatitis B, pathway in cancer, toll like receptor signaling pathway and type 2 diabetes mellitus (T2DM). The proteins of hypoxia inducible factor-1 (HIF1A), nuclear factor erythroid 2-related factor (NFE2L2), nitric oxide synthase 3 (NOS3), nuclear receptor subfamily 3 group C member 1 (NR3C1), PI3K catalytic subunit alpha (PIK3CA), and silencing information regulator 2 related enzyme 1 (SIRT1) may the core targets of metformin for the treatment of NAFLD.

CONCLUSION

Metformin might be a candidate drug for the treatment of NAFLD which exhibits therapeutic effect on NAFLD patients associated with ALT, AST, TG, TC and IR while was not correlated with BMI. HIF1A, NFE2L2, NOS3, NR3C1, PIK3CA, and SIRT1 might be core targets of metformin for the treatment of NAFLD.

Element Content in Different Wheat Flours and Bread Varieties

The most consumed cereal-based product worldwide is bread. “Caaveiro”, an autochthonous variety with a recent growing interest, is one of the wheat varieties that fulfill the 25% local flour requirement in the PGI “Pan Galego” bread baking industry. The element content of the refined wheat flours used to make “Pan Galego” (‘‘Caaveiro’’, FCv; Castilla, FC; and a mixture of both, FM) was evaluated in ICP-MS. In addition, wholegrain flour (FWM) was included in the analysis. Loaves of bread were made with these flours (a, 100% FC; b, 100% FCv); and c, FM: 75% FC + 25% FCv) and their element content was analyzed. Wholegrain flour ranked the highest in almost all elements, highlighting the P (494.80 mg/100 g), while the FM and the FC presented the opposite behavior, with the highest Se values (14.4 and 15.8 mg/100 g, respectively). FCv was situated in an intermediate position regarding P, K, Mg, Mn, Zn, Fe and Na content, standing closer to FWM, although it presents the highest values for Cu (1076.3 µg/100 g). The differences observed in flour were maintained in bread. Hence, the local cultivar ‘‘Caaveiro’’ has an interesting nutritional profile from the point of view of the element content.

Effects of whole-grain barley and oat β-glucans on postprandial glycemia and appetite: a randomized controlled crossover trial

This study aimed to determine the postprandial effects of barley bread (BB) and oat bread (OB), grain sources of β-glucans, on glycaemia and appetite by comparison with white bread (WB) and whole-wheat bread (WWB). This randomized controlled crossover trial included 20 healthy individuals (10 males and 10 females) who consumed WB, WWB, BB, and OB with a standard breakfast followed by an ad libitum lunch. Postprandial glucose and appetite responses were quantified as the incremental area under the curve (iAUC). Although the iAUC for glycaemic response was lower by 23.7%, 29.9%, and 27.9% after the consumption of BB, OB, and WWB compared with WB (p = 0.023), no differences were observed between BB, OB, and WWB (p > 0.05). BB had a lower iAUC for appetite sensation by 21.5%, 23.9%, and 55.7% compared with WB, WWB, and OB (p = 0.005). OB had no effect on appetite and was also less palatable than BB. Subsequent food intakes were similar after the consumption of all test breads (p > 0.05). The encouragement of healthier bread formulations that can beneficially modulate postprandial glycemia and appetite may contribute to the promotion of public health. This trial was registered at ClinicalTrials.gov as NCT04749498.

Bioactive Properties of Bread Formulated with Plant-based Functional Ingredients Before Consumption and Possible Links with Health Outcomes After Consumption- A Review

Bread is a commonly consumed staple and could be a viable medium to deliver plant-based ingredients that demonstrate health effects. This review brings together published evidence on the bioactive properties of bread formulated with plant-based ingredients. Health effects associated with the consumption of bread formulated with plant-based functional ingredients was also reviewed. Bioactive properties demonstrated by the functional ingredients fruits and vegetables, legumes, nuts and tea incorporated into bread include increased phenolic and polyphenolic content, increased antioxidant activity, and extension of bread shelf-life by impairment of lipid and protein oxidation. Acute health effects reported included appetite suppression, reduced diastolic blood pressure, improvements in glycaemia, insulinaemia and satiety effect. These metabolic effects are mainly short lived and not enough for a health claim. Longer term studies or comparison of those who consume and those who do not are needed. The incorporation of plant-based functional ingredients in bread could enhance the health-promoting effects of bread.

Consumption of sourdough bread and changes in the glycemic control and satiety: A systematic review

The aim of this study was to carry out a systematic review of clinical trials followed by meta-analysis, to evaluate the effect of sourdough bread on glycemic control and appetite and satiety regulators such as leptin, ghrelin, GLP-1 (glucagon-like peptide-1), GLP-2 (glucagon-like peptide-2), NPY (neuropeptide Y), AgRP (agouti-related protein), PYY (peptide YY), and GIP (glucose-dependent insulinotropic polypeptide). Clinical trials compared the intake of sourdough bread to that of an industrially fermented one or control glucose solution in adults over 18 years of age. This systematic review included all randomized, parallel, or crossover trials published up to June 2021 in the EMBASE, MEDLINE, Scopus, and Web of Science databases. After the selection process, 18 studies were included. The analysis of the final average difference of the change in serum glucose after 60 minutes for the intervention indicated that the consumption of sourdough bread has a lower impact on blood glucose compared to that of industrial bread or glucose (MD = -0.29, IC 95% = [-0.46; -0.12]; I2 = 0%). The evaluation of blood glucose 120 minutes after the consumption of the intervention also indicated a lower increment in blood glucose when compared to the consumption of other types of bread or the same amount of glucose (MD = -0.21, IC 95% = [-0.32; -0.09]; I2 = 0%). The certainty of evidence varied from low to very low. The results showed that sourdough is effective in reducing the increment of postprandial glycemia, especially when prepared with whole wheat flour, although it does not reduce fasting serum insulin, nor does it change plasma PYY.

Lactic acid bacteria synergistic fermentation affects the flavor and texture of bread

Fermentation strains play a key role in the quality of bread. The combination of yeast and lactic acid bacteria (LAB) may effectively improve the function and nutritional properties of bread. In this study, the dough was fermented to make bread by using single strain (Saccharomyces cerevisiae, mode A), the combination of two strains (S. cerevisiae and Lactiplantibacillus plantarum, mode B; S. cerevisiae and Lactobacillus delbrueckii, mode C), or three strains (S. cerevisiae, L. plantarum, and L. delbrueckii, mode D). The specific volume, texture, and aroma substances of bread were evaluated. The possibility of mixed fermentation of selected yeast and LAB to replace natural fermentation dough was evaluated. The results showed that the specific volume of bread in mode B was 15.2% higher than that of mode A. The structure was softer and the taste was more vigorous in mode B bread. The content of volatile compounds was highest in mode B bread among the four mode bread. The characteristic flavors were ethyl 2-hydroxypropionate and z-3-hexenol. The cofermentation in mode B made the bread aroma richer and gave better aroma characteristics to bread. Therefore, the fermentation of S. cerevisiae and L. plantarum can be recommended to replace naturally fermented dough to improve the quality of bread. PRACTICAL APPLICATION: L. plantarum and L. delbrueckii, separately or together, assisted in yeast fermentation to make bread. The specific volume, texture, and aroma substances of bread were evaluated to replace natural fermented dough with mixed fermentation. L. plantarum-assisted yeast fermentation improved the specific volume, texture, and aroma of bread. The characteristic flavors were ethyl 2-hydroxypropionate and z-3-hexenol in bread. Therefore, the fermentation of S. cerevisiae and L. plantarum could replace naturally fermented dough to improve the quality of bread.

Glycemic response, satiety, gastric secretions and emptying after bread consumption with water, tea or lemon juice: a randomized crossover intervention using MRI

PURPOSE

Numerous studies, including our previous work with lemon juice, have reported that low-pH meals reduce the glycemic response to starchy foods. However, the underlying mechanism is not yet understood. Tea, for its polyphenol content, has also been investigated. The main objective of this research was to concurrently study gastric emptying, appetite perceptions and glycemic responses to bread consumed with water, tea, or lemon juice.

METHODS

In this randomized, crossover intervention, ten participants consumed equal portions of bread (100 g) with 250 mL of water, water-diluted lemon juice, or black tea at breakfast. Gastric volumes, blood glucose concentrations and appetite perceptions were alternately assessed over 180 min using magnetic resonance imaging, the finger-prick method and visual analogue scales, respectively.

RESULTS

Compared to water, lemon juice led to a 1.5 fold increase of the volume of gastric contents, 30 min after the meal (454.0 ± 18.6 vs. 298.4 ± 19.5 mL, [Formula: see text]  ± SEM P < 0.00001). Gastric emptying was also 1.5 times faster (P < 0.01). Conversely, lemon juice elicited a lower glycemic response than water (blood glucose concentrations at t = 55 min were 35% lower, P = 0.039). Tea had no effect. Changes in appetite perceptions and gastric volumes correlated well, but with no significant differences between the meals.

CONCLUSIONS

Lemon juice lowered the glycemic response and increased both gastric secretions and emptying rate. The results are compatible with the hypothesis that the reduction of the glycemic response is mainly due to the interruption of starch hydrolysis via the acid-inhibition of salivary α-amylase.

TRIAL REGISTRATION NUMBER

NCT03265392, August 29, 2017.

Postprandial blood glucose and insulin responses to breads formulated with different wheat evolutionary populations (Triticum aestivum L.): A randomized controlled trial on healthy subjects

This study aimed to evaluate the effect of breads made with two different wheat evolutionary populations (EPs), compared with a modern variety, on postprandial blood glucose and insulin responses. A randomized controlled crossover postprandial study involving 12 healthy subjects was conducted. Seven non-commercial breads produced with flours from two different bread wheat (T. aestivum L.) EPs (Bio2, ICARDA) and a modern bread wheat variety (Bologna) were considered controls, with two different bread-making processes (Saccharomyces cerevisiae and sourdough), and were specifically formulated for the study. Postprandial incremental curves, incremental area under the curve (IAUC), maximum postprandial peaks for blood glucose and plasma insulin over 2 h after administration of isoglucidic portions of breads (50 g of available carbohydrates) were evaluated. The comparison of incremental curves, IAUC, and maximum postprandial peaks after consumption of breads formulated with EPs and control breads showed no differences among samples. Neither the flour nor the leavening technic used for the baking were effective in inducing a different postprandial response compared with the Bologna variety. EPs, being characterized by higher degree of crop genetic diversity, may have a relevant agronomic role to guarantee good and stable yields and quality under low input management in a changing climate; however, future studies are needed to better investigate their potential positive effect on human health.

Sourdough Microbiome Comparison and Benefits

Sourdough is the oldest form of leavened bread used as early as 2000 BC by the ancient Egyptians. It may have been discovered by accident when wild yeast drifted into dough that had been left out resulting in fermentation of good microorganisms, which made bread with better flavour and texture. The discovery was continued where sourdough was produced as a means of reducing wastage with little known (at that point of time) beneficial effects to health. With the progress and advent of science and technology in nutrition, sourdough fermentation is now known to possess many desirable attributes in terms of health benefits. It has become the focus of attention and practice in modern healthy eating lifestyles when linked to the secret of good health. The sourdough starter is an excellent habitat where natural and wild yeast plus beneficial bacteria grow by ingesting only water and flour. As each sourdough starter is unique, with different activities, populations and interactions of yeast and bacteria due to different ingredients, environment, fermentation time and its carbohydrate fermentation pattern, there is no exact elucidation on the complete make-up of the sourdough microbiome. Some lactic acid bacteria (LAB) strains that are part of the sourdough starter are considered as probiotics which have great potential for improving gastrointestinal health. Hence, from a wide literature surveyed, this paper gives an overview of microbial communities found in different sourdough starters. This review also provides a systematic analysis that identifies, categorises and compares these microbes in the effort of linking them to specific functions, particularly to unlock their health benefits.

Effect of Different Fermentation Condition on Estimated Glycemic Index, In Vitro Starch Digestibility, and Textural and Sensory Properties of Sourdough Bread

This study aimed to evaluate the influence of sourdough fermentation on the estimated glycemic index (eGI), in vitro starch digestibility, and textural and sensory properties of eight experimentally prepared sourdough breads. Wheat and whole wheat flour bread samples were produced under different fermentation conditions (25 °C and 30 °C) and fermentation methods (type-1 and type-2). In type-1 fermentation, sourdough was obtained via spontaneous fermentation. Indigenous strains (Lactobacillus brevis ELB99, Lactiplantibacillus plantarum ELB75, and Saccharomyces cerevisiae TGM55) were used for type-2 fermentation. Fermentation type and temperature significantly affected eGI, the hydrolysis index (HI), the starch fraction, and the textural properties of the samples (p < 0.05). The resistant starch (RS) content increased after fermentation, while rapidly digestible starch (RDS), HI, and eGI decreased. RS values were significantly higher in type-2 than in type-1 at the same temperature for both flour types (p < 0.05). At 25 °C, RS values were higher in both fermentation types. In the white flour samples, eGI values were in the range of 60.8–78.94 and 62.10–78.94 for type-1 and type-2, respectively. The effect of fermentation type on eGI was insignificant (p < 0.05). In the whole flour samples, fermentation type and temperature significantly affected eGI (p < 0.05). The greatest eGI decreases were in whole wheat sourdough bread at 30 °C using type-2 (29.74%). The 30 °C and type-2 samples showed lower hardness and higher specific volume. This study suggests that fermentation type and temperature could affect the eGI and the textural and sensory properties of sourdough bread, and these factors should be considered during bread production. The findings also support the consumption of wheat and whole wheat breads produced by type-2 fermentation due to higher RS and slowly digestible starch (SDS) and lower RDS and eGI values.

Natural Antioxidants Improve the Vulnerability of Cardiomyocytes and Vascular Endothelial Cells under Stress Conditions: A Focus on Mitochondrial Quality Control

Cardiovascular disease has become one of the main causes of human death. In addition, many cardiovascular diseases are accompanied by a series of irreversible damages that lead to organ and vascular complications. In recent years, the potential therapeutic strategy of natural antioxidants in the treatment of cardiovascular diseases through mitochondrial quality control has received extensive attention. Mitochondria are the main site of energy metabolism in eukaryotic cells, including myocardial and vascular endothelial cells. Mitochondrial quality control processes ensure normal activities of mitochondria and cells by maintaining stable mitochondrial quantity and quality, thus protecting myocardial and endothelial cells against stress. Various stresses can affect mitochondrial morphology and function. Natural antioxidants extracted from plants and natural medicines are becoming increasingly common in the clinical treatment of diseases, especially in the treatment of cardiovascular diseases. Natural antioxidants can effectively protect myocardial and endothelial cells from stress-induced injury by regulating mitochondrial quality control, and their safety and effectiveness have been preliminarily verified. This review summarises the damage mechanisms of various stresses in cardiomyocytes and vascular endothelial cells and the mechanisms of natural antioxidants in improving the vulnerability of these cell types to stress by regulating mitochondrial quality control. This review is aimed at paving the way for novel treatments for cardiovascular diseases and the development of natural antioxidant drugs.

Lemon juice, but not tea, reduces the glycemic response to bread in healthy volunteers: a randomized crossover trial

PURPOSE

The inhibition of enzymes that hydrolyze starch during digestion could constitute an opportunity to slow down the release, and ultimately the uptake, of starch-derived glucose. Simple dietary approaches consisting in pairing starch-rich foods with beverages that have the capacity to inhibit such enzymes could be an effective and easily implementable strategy. The objective of this work was to test the impact of black tea and lemon juice on the glycemic response to bread and subsequent energy intake in healthy adults.

METHODS

A randomized crossover study was conducted with equal portions of bread (100 g) and 250 ml of water, black tea or lemon juice. Capillary blood glucose concentrations were monitored during 180 min using the finger-prick method. Ad libitum energy intake was assessed 3 h later.

RESULTS

Tea had no effect on the glycemic response. Lemon juice significantly lowered the mean blood glucose concentration peak by 30% (p < 0.01) and delayed it more than 35 min (78 vs. 41 min with water, p < 0.0001). None of the tested beverages had an effect on ad libitum energy intake.

CONCLUSION

These results are in agreement with previous in vitro studies showing that lowering the pH of a meal can slow down starch digestion through premature inhibition of salivary α-amylase. Furthermore, the effect of lemon juice was similar to what has been repeatedly observed with vinegar and other acidic foods. Including acidic beverages or foods in starchy meals thus appears to be a simple and effective strategy to reduce their glycemic impact.

Acid induced reduction of the glycaemic response to starch-rich foods: the salivary α-amylase inhibition hypothesis

Numerous studies have reported that the glycaemic response to starch-rich meals can be reduced by 20-50% with acidic drinks or foods. A number of candidate explanations have been put forward, but this phenomenon still remains vaguely understood. This study intends to demonstrate the remarkable effect of acid inhibition of salivary α-amylase during oro-gastric hydrolysis of starch, shedding light on this often overlooked mechanism. Oro-gastric digestions of bread, wheat and gluten-free pastas, combined with either water or lemon juice were performed using a dynamic in vitro system that reproduces gastric acidification kinetics observed in humans. In the presence of water, large proportions of starch (25-85%) and oligosaccharides (15-50%) were released from all foods within the first hour of gastric digestion (pH > 3.5). In the presence of lemon juice (pH < 3.5 at all time), starch release was about twice as low, and amylolysis into oligosaccharides was completely interrupted. Acid-inhibition of salivary α-amylase may explain, at least in part, the reduction of the blood glucose response through acidification of starch-rich foods/meals. This offers new perspectives for the development of strategies to improve the glycaemic response elicited by starch-rich diets.

In Vivo Effects of Einkorn Wheat (Triticum monococcum) Bread on the Intestinal Microbiota, Metabolome, and on the Glycemic and Insulinemic Response in the Pig Model

Einkorn wheat (Triticum monococcum) is characterized by high content of proteins, bioactive compounds, such as polyunsaturated fatty acids, fructans, tocols, carotenoids, alkylresorcinols, and phytosterols, and lower α-, β-amylase and lipoxygenase activities compared to polyploid wheat. These features make einkorn flour a good candidate to provide healthier foods. In the present study, we investigated the effects of einkorn bread (EB) on the intestinal physiology and metabolism of the pig model by characterizing the glycemic and insulinemic response, and the microbiota and metabolome profiles. Sixteen commercial hybrid pigs were enrolled in the study; four pigs were used to characterize postprandial glycemic and insulinemic responses and twelve pigs underwent a 30-day dietary intervention to assess microbiota and metabolome changes after EB or standard wheat bread (WB) consumption. The postprandial insulin rise after an EB meal was characterized by a lower absolute level, and, as also observed for glucose, by a biphasic shape in contrast to that in response to a WB meal. The consumption of EB led to enrichment in short-chain fatty acid producers (e.g., Blautia, Faecalibacterium, and Oscillospira) in the gut microbiota and to higher metabolic diversity with lower content of succinate, probably related to improved absorption and therefore promoting intestinal gluconeogenesis. The observed changes, at both a compositional and metabolic scale, strongly suggest that EB consumption may support a health-promoting configuration of the intestinal ecosystem.

Postprandial Gastrointestinal Function Differs after Acute Administration of Sourdough Compared with Brewer's Yeast Bakery Products in Healthy Adults

Background

Europeans consume large quantities of bakery products, although these are known as one of the food categories that potentially leads to postprandial symptoms (such as fullness and bloating).

Objective

The aim of this study was to evaluate the effects of sourdough baked goods on gastric emptying and gastrointestinal fermentation and symptoms in healthy people.

Methods

In a double-blind, randomized crossover study, 2 sourdough croissants (SCs) or 2 brewer's yeast croissants (BCs) were served as single meals to 17 healthy adults [9 women; age range: 18-40 y; body mass index range (in kg/m2): 18-24]. Gastric volume (GV) was evaluated by magnetic resonance to calculate gastric-emptying rate in the 3-h interval after croissant ingestion. A hydrogen breath test was performed to measure hydrogen production after SC and BC ingestion. Palatability and postprandial gastrointestinal symptoms (discomfort, nausea, fullness, and bloating) over a 4-h period after the meal were evaluated. The area under the curve (AUC) was used to evaluate the overall effects on all variables tested.

Results

The total GV AUC was reduced by 11% during the 3 h after the consumption of SCs compared with BCs (P = 0.02). Hydrogen production during the 4-h interval after ingestion of SCs was 30% lower than after BCs (P = 0.03). SCs were rated as being >2 times as palatable as BCs (P < 0.001). The overall severity of postprandial symptoms was 36% lower during the 4 h after intake of SCs compared with BCs (P = 0.05).

Conclusion

Sourdough bakery products could promote better postprandial gastrointestinal function in healthy adults and be more acceptable than those prepared with brewer's yeast. This trial was registered at www.clinicaltrials.gov as NCT03207516.