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1.
Food Chem ; 462: 140987, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217748

RESUMO

This study aimed to investigate the textural changes of cooked germinated brown rice (GBR) during freeze-thaw treatment and propose a strategy for enhancing its texture using magnetic field (MF). Seven freeze-thaw cycles exhibited more pronounced effects compared to 7 days of freezing, resulting in increases in GBR hardness by 85.59 %-164.36 % and decreases in stickiness by 10.34 %-43.55 %. Water loss, structural damage of GBR flour, and starch retrogradation contributed to the deterioration of texture. MF mitigated these effects by inhibiting the transformation of bound water into free water, reducing water loss by 0.39 %-0.57 %, and shortening the phase transition period by 2.0-21.5 min, thereby diminishing structural damage to GBR flour and hindering starch retrogradation. Following MF treatment (5 mT), GBR hardness decreased by 21.00 %, while stickiness increased by 45.71 %. This study elucidates the mechanisms through which MF enhances the texture, offering theoretical insights for the industrial production of high-quality frozen rice products.


Assuntos
Culinária , Congelamento , Germinação , Campos Magnéticos , Oryza , Oryza/química , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Farinha/análise , Amido/química , Amido/metabolismo , Água/química , Dureza , Manipulação de Alimentos , Sementes/química , Sementes/crescimento & desenvolvimento
2.
J Agric Food Chem ; 72(37): 20458-20469, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39230615

RESUMO

Our previous study proved that epicatechin (EC) and ß-glucan (BG) from whole-grain highland barley synergistically modulate glucose metabolism in insulin-resistant HepG2 cells. However, the main target and the mechanism underlying the modulation of glucose metabolism in vivo remain largely unknown. In this study, cell transfection assay and microscale thermophoresis analysis revealed that EC and BG could directly bind to the insulin receptor (IR) and mammalian receptor for rapamycin (mTOR), respectively. Molecular dynamic analysis indicated that the key amino acids of binding sites were Asp, Met, Val, Lys, Ser, and Tys. EC supplementation upregulated the IRS-1/PI3K/Akt pathway, while BG upregulated the mTOR/Akt pathway. Notably, supplementation with EC + BG significantly increased Akt and glucose transporter type 4 (GLUT4) protein expressions, while decreasing glycogen synthase kinase 3ß (GSK-3ß) expression in liver cells as compared to the individual effects of EC and BG, indicating their synergistic effect on improving hepatic glucose uptake and glycogen synthesis. Consistently, supplementation with EC + BG significantly decreased blood glucose levels and improved oral glucose tolerance compared to EC and BG. Therefore, combined supplementation with EC and BG may bind to corresponding receptors, targeting synergistic activation of Akt expression, leading to the improvement of hepatic glucose metabolism and thereby ameliorating hyperglycemia in vivo.


Assuntos
Catequina , Glucose , Hordeum , Hiperglicemia , Fígado , Camundongos Endogâmicos C57BL , beta-Glucanas , Hordeum/química , beta-Glucanas/farmacologia , beta-Glucanas/química , Animais , Camundongos , Catequina/farmacologia , Catequina/administração & dosagem , Fígado/metabolismo , Fígado/efeitos dos fármacos , Masculino , Humanos , Glucose/metabolismo , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Sinergismo Farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Transportador de Glucose Tipo 4/metabolismo , Transportador de Glucose Tipo 4/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicemia/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Células Hep G2
3.
Foods ; 13(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39335918

RESUMO

The growing scientific evidence on the health benefits of whole-grain food consumption has promoted the manufacturing of a great number of products differing in quality and content of whole-grain components. This is particularly true for commercial wheat-based products where it is not always clear how much whole wheat is present considering that in many cases, they are manufactured from reconstituted mill streams and that there is not a standardised globally accepted definition and metrics to objectively evaluate whole-grain status. Attempts have been made to assess the level of "wholegraininess" in wheat products by measuring specific constituents that correlate with different wheat tissues, especially those that are expected to be found in a true whole-grain wheat product. Wheat germ agglutinin (WGA), a small lectin protein present exclusively in the wheat-germ tissues, has been indicated by several scientists as one of these constituents and after founding that its level changes depending on the amount of germ found in a wheat flour, it has been indicated as a biomarker of whole-grain status for wheat products. In this review, the biochemistry of WGA, its methods of detection, and current knowledge on its possibility to be practically utilized as a reliable marker are critically discussed.

4.
Foods ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39123508

RESUMO

The aim of this study was to assess the advantages of an industry-scale microfluidizer system (ISMS) to prepare whole-grain highland barley pulp (WHBP) compared with colloid milling. Storage stability was evaluated by particle size, gravity separation stability, and rheological properties, as well as the microstructure observation by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLMS). The results showed that colloid milling failed to effectively homogenize the material, while ISMS sample surfaces were compact and smooth at higher pressures according to visual observation and SEM. The Turbiscan stability index of WHBP by ISMS was much lower as a result of colloid milling, demonstrating ISMS can improve WHBP stability. WHBP by colloid milling displayed a three-peak particle size distribution pattern, while a single-peak pattern was evident after ISMS treatment. A higher shear rate decreased the apparent viscosity, suggesting that WHBP was a shear-thinning fluid. According to CLMS, ISMS can successfully improve homogenization by disrupting the structures of oil bodies, proteins, and starches. The WHBP prepared by ISMS exhibited a higher ß-glucan level than that prepared by colloid milling, and showed a significant increase in ß-glucan level with ISMS pressure. These findings indicate that using ISMS to produce WHBP is viable for enhancing its storage stability and nutritional value.

5.
Food Chem ; 461: 140862, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39167950

RESUMO

This study aimed to enhance bread functionality while maintaining its organoleptic attributes by employing superfine grinding and purple wheat, through characterizing dough properties, bread quality attributes, and in vitro starch digestibility. Compared with dough made from commercial-superfine-whole-wheat flour, the superfine-whole-purple-wheat dough was less strong, comparably extensible, and higher in gassing power during mixing, moulding and proofing, respectively. The subsequent bread quality analysis of crumb grain features and texture indicated that the bread made from superfine-whole-purple-wheat flour was more porous and softer with a larger specific volume (3.21 ± 0.20 cm3/g) than that made from commercial-superfine-whole-wheat flour (2.30 ± 0.17 cm3/g). Additionally, the superfine-whole-purple-wheat bread had a significantly slower glucose release (k = 0.0048 min-1) during in vitro starch digestion as compared to the superfine-whole-wheat bread (k = 0.0065 min-1). Therefore, this study demonstrates that using superfine-whole-purple-wheat flour leads to bread with desirable quality attributes and potential health benefits compared to conventional whole-wheat flour.


Assuntos
Pão , Digestão , Farinha , Amido , Triticum , Pão/análise , Amido/química , Amido/metabolismo , Triticum/química , Triticum/metabolismo , Farinha/análise , Manipulação de Alimentos , Humanos , Tamanho da Partícula
6.
Nutrients ; 16(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38999732

RESUMO

Low wholegrain food consumption is a leading dietary risk for avoidable morbidity and mortality globally, with limited sensory acceptability suggested to be a challenge for changing behaviour. This study aimed to evaluate the sensory acceptability of both wholegrain (brown) and refined (white) rice in common preparations. Four brown- and white-rice-containing dishes (Garlic Rice, Rice and Beans, Jollof Rice, and Rice Pudding) were tested. Quantitative (five-point scales) and qualitative (open question responses) sensory information were collected for dish appearance, aroma, taste, and texture. All four characteristics were scored equally acceptable in Rice and Beans and Rice Pudding (p > 0.05) between paired comparisons for brown and white rice. Scores were significantly lower for all characteristics for Jollof Rice (p ≤ 0.002), and lower for Aroma (median (lower quartile-upper quartile)) for brown (3.5 (3-4)) vs. white rice (4 (4-5)), p = 0.006). Appearance (brown (3 (3-4)) vs. white rice (4 (3.25-5)), p = 0.012), and Texture (brown 3 (2.25-4) vs. white rice (4 (4-5)), p < 0.001) for Garlic Rice. Familiarity and appealingness were qualitative themes aligned with the higher acceptability of white-rice-containing dishes. Certain dishes appear to mask key negative sensory attributes of wholegrain foods, possibly representing a means to increase wholegrain ingredient acceptability, thereby potentially improving individual/population-level intake.


Assuntos
Oryza , Paladar , Oryza/química , Humanos , Feminino , Masculino , Adulto , Grãos Integrais , Pessoa de Meia-Idade , Adulto Jovem , Preferências Alimentares , Odorantes/análise , Comportamento do Consumidor
7.
Foods ; 13(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928784

RESUMO

A whole-grain highland barley (WHB) diet has been recognized to exhibit the potential for alleviating hyperlipidemia, which is mainly characterized by lipids accumulation in the serum and liver. Previously, procyanidin B1 (PB) and coumaric acid (CA) from WHB were found to alleviate serum lipid accumulation in impaired glucose tolerance mice, while the effect on modulating the hepatic lipid metabolism remains unknown. In this study, the results showed the supplementation of PB and CA activated the expression of peroxisome proliferator-activated receptor α (PPARα) and the target genes of cholesterol 7-α hydroxylase (CYP7A1) and carnitine palmitoyl transferase I (Cpt1) in the liver cells of high-fat-diet (HFD)-induced diabetic C57BL/6J mice, resulting in decreases in the serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL-C) contents, and an increase in the high-density lipoprotein (HDL-C) content. High-throughput sequencing of 16S rRNA indicated that supplementation with PB and CA ameliorated the gut microbiota dysbiosis, which was associated with a reduction in the relative abundance of Ruminococcaceae and an increase in the relative abundance of Lactobacillus, Desulfovibrio, and Akkermansia. Spearman's correlation analysis revealed that these genera were closely related to obesity-related indices. In summary, the activation of PPARα expression by PB and CA from WHB was important for the alleviation of hyperlipidemia and the structural adjustment of the gut microbiota.

8.
J Poult Sci ; 61: 2024016, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827264

RESUMO

Lactobacillus spp. inhibit the growth of Campylobacter spp. in vitro. However, in chicken crops, in which Lactobacillus spp. predominate, such inhibition of Campylobacter has not been confirmed. In our previous study, feeding paddy rice to broiler chicks increased the residence time of the food, which might enhance the bactericidal activity of the crop. Here, the bactericidal activity against the remaining Campylobacter spp. in broiler crops was evaluated. A suspension prepared by mixing Campylobacter jejuni and titanium dioxide (TiO2) was inoculated into the pharynx of 26-day-old broiler chicks fed a paddy rice-based diet. The crop contents were sampled at 20-min intervals. The TiO2 residual ratio in the crop gradually decreased with time after inoculation, with 57% of the inoculated TiO2 remaining in the crop 60 min after inoculation. The survival fraction of C. jejuni in the crops was 11% at 40 min, only 1% at 60 min, and was undetectable at 80 min. Most of the inoculated C. jejuni died in the crop before entering the next segment. These data indicated that bacterial death occurred between 30 min and 40 min after inoculation. The average survival time of C. jejuni in the crop was calculated to be 37.1 min. Thus, C. jejuni remaining in a chicken crop for more than 40 min died.

9.
Food Sci Nutr ; 12(6): 3910-3919, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873465

RESUMO

Triticale (×Triticosecale) is a hybrid between wheat (Triticum spp.) and rye (Secale cereale), producing higher grain yields than wheat in challenging environments. Triticale grain is also highly nutritious. Thus, the potential of triticale grain for an expanded range of food applications should be explored. Sourdough bread has unique functional and nutritional properties, but understanding the effects of partial substitution of triticale for wheat flour and varying levels of dough moisture content on sourdough quality requires further research. The aim of this study was to evaluate the wholegrain flour of contrasting triticale cultivars in comparison to that of a common wheat cultivar in commercial sourdough breadmaking. Two triticale cultivars (Goanna and Hawkeye, selected from a panel of Australian genotypes) and one wheat cultivar (Scout) were grown in a field trial in northern NSW, Australia. Differences in quantitative texture and color parameters of the dough and sourdough bread resulting from (1) substitution of commercial wholemeal wheat flour with different proportions of wholegrain triticale or wholegrain wheat (Scout) flour (0%, 60%, 70%, 80%, and 90%) and (2) varying the amount of water included in the dough preparation (70%, 80%, 90%, and 100 g water/100 g flour) were determined. Replacement of wholemeal wheat flour with 60% wholegrain Goanna flour (protein content 12.76%; c.f. 11.50% for Hawkeye, 12.40% for Scout), and addition of 100 g water/100 g flour in the dough preparation gave the highest quality sourdough bread based on specific volume, texture, and color parameters and had similar properties to the control made from wheat alone.

10.
Nutrients ; 16(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38613022

RESUMO

A low-fibre diet leads to gut microbiota imbalance, characterized by low diversity and reduced ability to produce beneficial metabolites, such as short-chain fatty acids (SCFAs). This imbalance is associated with poor gastrointestinal and metabolic health. We aimed to determine whether one dietary change, substitution of white bread with high-fibre bread, improves gut microbiota diversity and SCFA-producing capability. Twenty-two healthy adults completed a two-phase randomized, cross-over trial. The participants consumed three slices of a high-fibre bread (Prebiotic Cape Seed Loaf with BARLEYmax®) or control white bread as part of their usual diet for 2 weeks, with the treatment periods separated by a 4-week washout. High-fibre bread consumption increased total dietary fibre intake to 40 g/d, which was double the amount of fibre consumed at baseline or during the white bread intervention. Compared to white bread, the high-fibre bread intervention resulted in higher faecal alpha diversity (Shannon, p = 0.014) and relative abundance of the Lachnospiracae ND3007 group (p < 0.001, FDR = 0.019) and tended to increase the butyrate-producing capability (p = 0.062). In conclusion, substituting white bread with a high-fibre bread improved the diversity of gut microbiota and specific microbes involved in SCFA production and may enhance the butyrate-producing capability of gut microbiota in healthy adults. These findings suggest that a single dietary change involving high-fibre bread provides a practical way for adults to exceed recommended dietary fibre intake levels that improve gut microbiota composition and support gastrointestinal and metabolic health.


Assuntos
Pão , Microbiota , Adulto , Humanos , Ácidos Graxos Voláteis , Butiratos , Bactérias , Prebióticos
11.
J Sci Food Agric ; 104(7): 4371-4382, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38459765

RESUMO

BACKGROUND: Whole-grain rice noodles are a kind of healthy food with rich nutritional value, and their product quality has a notable impact on consumer acceptability. The quality evaluation model is of great significance to the optimization of product quality. However, there are few methods that can establish a product quality prediction model with multiple preparation conditions as inputs and various quality evaluation indexes as outputs. In this study, an artificial neural network (ANN) model based on a backpropagation (BP) algorithm was used to predict the comprehensive quality changes of whole-grain rice noodles under different preparation conditions, which provided a new way to improve the quality of extrusion rice products. RESULTS: The results showed that the BP-ANN using the Levenberg-Marquardt algorithm and the optimal topology (4-11-8) gave the best performance. The correlation coefficients (R2) for the training, validation, testing, and global data sets of the BP neural network were 0.927, 0.873, 0.817, and 0.903, respectively. In the validation test, the percentage error in the quality prediction of whole-grain rice noodles was within 10%, indicating that the BP-ANN could accurately predict the quality of whole-grain rice noodles prepared under different conditions. CONCLUSION: This study showed that the quality prediction model of whole-grain rice noodles based on the BP-ANN algorithm was effective, and suitable for predicting the quality of whole-grain rice noodles prepared under different conditions. © 2024 Society of Chemical Industry.


Assuntos
Oryza , Redes Neurais de Computação , Algoritmos , Grãos Integrais , Valor Nutritivo
12.
Antioxidants (Basel) ; 13(2)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38397823

RESUMO

Apple pomace (AP) is a bio-waste product of apples that is co-produced as a by-product during apples' processing for making apple-based products, mainly apple juice, cider and vinegar. AP is a rich source of several bioactives that can be valorized as ingredients for developing novel functional foods, supplements and nutraceuticals. Within the present study, food-grade extracts from AP with different tannin contents were found to contain bioactive polar lipids (PLs), phenolics and carotenoids with strong anti-oxidant, antithrombotic and anti-inflammatory properties. The extract from the low-in-tannins AP showed stronger anti-inflammatory potency in human platelets against the potent thrombo-inflammatory mediator platelet-activating factor (PAF), while it also exhibited considerable anti-platelet effects against the standard platelet agonist, adenosine diphosphate (ADP). The infusion of 0.5-1.0 g of this bioactive AP extract as functional ingredients for whole-grain bread-making resulted in the production of novel bio-functional bread products with stronger anti-oxidant, antithrombotic and anti-inflammatory potency against both PAF and ADP in human platelets, compared to the standard non-infused control breads. Structural analysis by LCMS showed that the PL-bioactives from all these sources (AP and the bio-functional breads) are rich in bioactive unsaturated fatty acids (UFA), especially in the omega-9 oleic acid (OA; 18:1n9), the omega-3 alpha linolenic acid (ALA; 18:n3) and the omega-6 linoleic acid (LA; 18:2n6), which further supports their strong anti-inflammatory and antithrombotic properties. All food-grade extracted AP including that infused with AP-bioactives novel functional breads showed higher hydrophilic, lipophilic and total phenolic content, as well as total carotenoid content, and subsequently stronger antioxidant capacity. These results showed the potential of appropriately valorizing AP-extracts in developing novel bio-functional bakery products, as well as in other health-promoting applications. Nevertheless, more studies are needed to fully elucidate and/or validate the anti-inflammatory, antithrombotic and antioxidant potential of novel bio-functional products across the food and cosmetic sectors when infused with these AP bioactives.

13.
Foods ; 13(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338530

RESUMO

The whole-grain, hulled Tartary buckwheat flour (HTBF) with outstanding bioactive functions was prepared, and the effects of partial substitution ratios (0, 30%, 51% and 70%) of wheat flour with HTBF on the characteristics of TB noodles (TBNs) were investigated, mainly including the cooking characteristics, sensory analysis, internal structure, bioactive components, and in vitro starch digestibility. With an increasing replacement level of HTBF, the water absorption index of the noodles decreased, whereas the cooking loss increased. A sensory analysis indicated that there were no off-flavors in all TBN samples. The scanning electron microscope images presented that the wheat noodles, 30% TBNs and 70% TBNs had dense and uniform cross sections. Meanwhile, the deepest color, V-type complexes, and lowest crystallinity (13.26%) could be observed in the 70% TBNs. A HTBF substitution increased the rutin content and the total phenolic and flavonoid contents in the TBNs, and higher values were found in the 70% TBNs. Furthermore, the lowest rapidly digestible starch content (16%) and highest resistant starch content (66%) were obtained in the 70% TBNs. Results demonstrated that HTBF could be successfully applied to make TBNs, and a 70% substitution level was suggested. This study provides consumers with a good option in the realm of special noodle-type products.

14.
Nutrients ; 15(21)2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37960346

RESUMO

According to unofficial data, every fifth person in Serbia suffers from some form of irritable bowel syndrome (IBS). Compounds classified as FODMAPs (Fermentable Oligo-, Di-, and Monosaccharides and Polyols) are newly found potential triggers of IBS and a number of associated gastrointestinal disorders. Cereals, predominantly in their wholegrain form, represent the key contributors to the high contents of FODMAPs in wholegrain (high-fiber) bakery products. The current work was structured in a way to systematically evaluate the consumer's knowledge and preferences toward wholegrain and low-FODMAP bakery products. The questionnaire was filled out by 725 respondents, aged from 18 to 86 years. They were informed about the aim of the research and management of anonymous data. The present study is the first detailed survey in this region of Europe, aiming to improve the familiarity with and attitude toward FODMAPs and a low-FODMAP diet by analyzing the different dietary habits regarding wholegrain-cereal-based products among consumers of various ages, genders, places of residence, and education. The results suggest that the respondents are, to some degree, aware of the health benefits of consuming foods with high fiber content while indicating a low level of knowledge about FODMAP compounds and connected topics. Education about contemporary scientific findings and the potentially harmful effects of consuming FODMAP compounds for a population with gastrointestinal disorders and diseases will be imperative in the future.


Assuntos
Síndrome do Intestino Irritável , Oligossacarídeos , Humanos , Masculino , Feminino , Sérvia , Carboidratos , Monossacarídeos/efeitos adversos , Fermentação , Dissacarídeos
15.
Nutr Bull ; 48(4): 587-593, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37904716

RESUMO

Dietary fibre is beneficial for human health, but dietary intakes are below recommended levels in most countries. Cereals are the major source of dietary fibre in Western diets, with bread providing about 20% of the daily intake in the United Kingdom. Despite the promotion of fibre-rich wholegrain products, white bread (which has a lower fibre content) remains dominant in many countries due to cultural preferences. Increasing the fibre content of white bread and other products made from white flour is therefore an attractive strategy for increasing fibre intake. This can be achieved by exploiting genetic variation in wheat without major effects on the processing quality or the consumer acceptability of products. Modelling data for food consumption in the United Kingdom shows that increasing the fibre content of white flour by 50% (from about 4% to 6% dry weight) and in wholegrain by 20% will increase total fibre intake by 1.04 g/day and 1.41 g/day in adult females and males, respectively. Furthermore, in vitro studies indicate that the increased fibre content of white bread should reduce the rate of starch digestion and glucose release in the human gastrointestinal tract.


Assuntos
Pão , Farinha , Masculino , Adulto , Feminino , Humanos , Amido , Fibras na Dieta , Trato Gastrointestinal , Triticum
16.
Foods ; 12(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685103

RESUMO

Sea buckthorn pomace is a by-product of juice production, which is still rich in bioactive compounds. After drying, the pomace can be effectively used as a valuable addition to bakery products supporting their nutritional value. However, due to the high content of the amino acid asparagine in sea buckthorn, this promising material contributes to the undesirable formation of acrylamide. To reduce the risk from this potentially carcinogenic compound, enzymatic treatment of sea buckthorn with asparaginase was applied, which resulted in a substantial reduction of asparagine content from 1834 mg/kg in untreated dried sea buckthorn pomace to 89 mg/kg in enzymatically treated dried sea buckthorn pomace. 10% substitution of wholegrain cereal flour with enzymatically treated sea buckthorn pomace powder in rye and triticale biscuits resulted in a 35% reduction in acrylamide content, in the case of wholegrain wheat biscuits up to a 64% reduction, compared to biscuits with untreated sea buckthorn pomace powder. This study confirmed that treating fruit with asparaginase is an effective way to reduce health risk caused by acrylamide in biscuits enriched with nutritionally valuable fruit pomace.

17.
J Sci Food Agric ; 103(15): 7683-7693, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37452647

RESUMO

BACKGROUND: New strategies in the cereal-based industry has brought about the elaboration of new sourdoughs with better microbial stability and safety as well as nutritional value such as those based on wholegrain flours. This has led to an increasing interest in the selection of adapted yeasts for using them as new starters. Therefore, this study aimed to isolate, identify, and characterise diverse yeast strains from wholegrain spontaneous sourdoughs. RESULTS: Three wholegrain sourdoughs (wheat, rye, and oat) were fermented and monitored for 96 h. Minimum pH values ranged from 3.1 to 3.5 while maximum yeast counts were reached at 72 h. A total of 76 yeast isolates were identified by polymerase chain reaction random amplification of polymorphic DNA (PCR-RAPD) and catalogued in six different species by sequencing the internal transcribed spacer (ITS) region. The major species were Candida glabrata, Saccharomyces cerevisiae, Kazachstania unispora, and Wickerhamomyces anomalus. The studied kinetic parameters of the growth curves (λ, G, ODmax , and µmax ) and the fermentation capacity allowed to ascertain that 12 and 5 strains, respectively, were better than baker's yeast control. The fibre assimilation ability (cellulose, xylose, and ß-glucan) was observed in the 27% of the strains and only four strains showed phytase activity. CONCLUSIONS: The yeast population in the three wholegrain sourdoughs were variable along the fermentation time. Genetic identification showed that strains and species presented a different trend for each sourdough although common species were determined (e.g., W. anomalus). Candida glabrata (4T1) and Saccharomyces cerevisiae (3A6) showed, respectively, better kinetics and impedance results than the positive control, while W. anomalus (C4) was notorious in fibre assimilation and phytase degradation. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
6-Fitase , Microbiota , Saccharomyces cerevisiae/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Fermentação , Pão , Microbiologia de Alimentos
18.
Foods ; 12(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37509839

RESUMO

By avoiding the filtration step and utilizing the whole components of oats, the highest utilization rate of raw materials, improving the nutritional value of products and reducing environmental pollution, can be achieved in the production of whole-grain oat drinks. This study innovatively introduced a dynamic high-pressure microfluidizer (DHPM) into the processing of whole-grain oat pulp, which aimed to achieve the efficient crushing, homogenizing and emulsification of starch, dietary fiber and other substances. Due to DHPM processing, the instability index and slope value were reduced, whereas the ß-glucan content, soluble protein content and soluble dietary fiber content were increased. In the samples treated with a pressure of 120 MPa and 150 MPa, 59% and 67% more ß-glucan content was released, respectively. The soluble dietary fiber content in the samples treated with a pressure of 120 MPa and 150 MPa was increased by 44.8% and 43.2%, respectively, compared with the sample treated with a pressure of 0 MPa. From the perspective of the relative stability of the sample and nutrient enhancement, the processing pressure of 120 MPa was a good choice. In addition, DHPM processing effectively reduced the average particle size and the relaxation time of the water molecules of whole-grain oat pulp, whereas it increased the apparent viscosity of whole-grain oat pulp; all of the above changes alleviated the gravitational subsidence of particles to a certain extent, and thus the overall stability of the system was improved. Furthermore, CLSM and AFM showed that the samples OM-120 and OM-150 had a more uniform and stable structural system as a whole. This study could provide theoretical guidance for the development of a whole-grain oat drink with improved quality and consistency.

19.
Front Nutr ; 10: 1187165, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324737

RESUMO

Background: Diets rich in whole grains are associated with health benefits. Yet, it remains unclear whether the benefits are mediated by changes in gut function and fermentation. Objective: We explored the effects of whole-grain vs. refined-grain diets on markers of colonic fermentation and bowel function, as well as their associations with the gut microbiome. Methods: Fifty overweight individuals with increased metabolic risk and a high habitual intake of whole grains (~69 g/day) completed a randomised cross-over trial with two 8-week dietary intervention periods comprising a whole-grain diet (≥75 g/day) and a refined-grain diet (<10 g/day), separated by a washout period of ≥6 weeks. A range of markers of colonic fermentation and bowel function were assessed before and after each intervention. Results: The whole-grain diet increased the levels of faecal butyrate (p = 0.015) and caproate (p = 0.013) compared to the refined-grain diet. No changes in other faecal SCFA, BCFA or urinary levels of microbial-derived proteolytic markers between the two interventions were observed. Similarly, faecal pH remained unchanged. Faecal pH did however increase (p = 0.030) after the refined-grain diet compared to the baseline. Stool frequency was lower at the end of the refined-grain period compared to the end of the whole-grain diet (p = 0.001). No difference in faecal water content was observed between the intervention periods, however, faecal water content increased following the whole-grain period compared to the baseline (p = 0.007). Dry stool energy density was unaffected by the dietary interventions. Nevertheless, it explained 4.7% of the gut microbiome variation at the end of the refined-grain diet, while faecal pH and colonic transit time explained 4.3 and 5%, respectively. Several butyrate-producers (e.g., Faecalibacterium, Roseburia, Butyriciococcus) were inversely associated with colonic transit time and/or faecal pH, while the mucin-degraders Akkermansia and Ruminococcaceae showed the opposite association. Conclusion: Compared with the refined-grain diet, the whole-grain diet increased faecal butyrate and caproate concentrations as well as stool frequency, emphasising that differences between whole and refined grains affect both colonic fermentation and bowel habits.

20.
Nutrients ; 15(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37299419

RESUMO

BACKGROUND: Accurate assessment of self-reported appetite under free-living conditions is warranted to conduct large-scale intervention studies measuring appetite at a feasible cost. However, the performance of visual analogue scales (VASs) for this purpose has not been widely examined. METHOD: This randomized crossover trial was conducted to evaluate VASs in free-living vs. clinic-based settings and to assess appetite response following hypocaloric whole-grain rye and refined wheat diets. Twenty-nine healthy adults with overweight or obesity continuously answered VAS questions about their perceived appetite from morning to evening. RESULTS: No differences in whole-day VAS scores (primary outcome) between clinic-based and free-living settings were observed, whereas measures of total area under the curve (tAUC) showed increased fullness in clinic-based interventions of 7% (p < 0.008) for whole-day responses and 13% (p < 0.03) following a snack. Appetite responses for a whole day did not differ between diets whereas rye-based dinners induced 12% (p < 0.016) higher fullness and reduced hunger by 17% (p < 0.02) irrespective of setting. A reduction in hunger of 15% (p < 0.05) was also observed following rye-based vs. wheat-based lunches. CONCLUSION: The results suggest that the VAS is valid for evaluation of appetite responses between diets under free-living conditions. No difference in self-reported appetite over the whole day was found after whole-grain rye vs. refined wheat-based diets, but there were some suggested differences at certain postprandial periods, in individuals with overweight or obesity.


Assuntos
Apetite , Triticum , Adulto , Humanos , Secale , Estudos Cross-Over , Sobrepeso , Fibras na Dieta/farmacologia , Dieta , Obesidade , Período Pós-Prandial
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