Effect of maize germ protein hydrolysate addition on digestion, in vitro antioxidant activity and quality characteristics of bread

Quality analysis of dough and steamed bread under various freezing conditions

Freezing is a crucial step in the process of frozen foods. In this study, the effects of different freezing methods, including liquid nitrogen immersion freezing (LF), quick-freezing machine freezing (QF), packaging immersion freezing (PF), and ultralow temperature refrigerator freezing (UF), and freezing time (0, 15, 30, and 60 days) on the textural properties, dynamic rheological properties, water distribution, and structure of dough and the quality of end steamed bread were evaluated. Freezing resulted in a decline in the physicochemical properties of dough. UF- and QF-doughs had higher storage modulus and loss modulus, compared with PF- and LF-doughs. LF enhanced the textural attributes of the dough, resulting in reduced hardness and increased springiness. At 15 days of freezing, QF- and LF-doughs exhibited a compact and continuous structure with a smooth surface. Additionally, the correlation analysis elucidated that the weight loss rate and the bound water content of the dough had discernible impacts on the texture of both the dough and the resulting steamed bread. Overall, LF demonstrated a relatively high freezing efficiency and effectively maintained the quality of the dough for up to 15 days of freezing. These results offer valuable insights for the applications of freezing methods and time in frozen foods.

Brewers spent grain protein hydrolysate as a functional ingredient for muffins: Antioxidant, antidiabetic, and sensory evaluation

This study assessed the fortification of muffins with 2, 4, and 6 % of brewer's spent grain protein hydrolysates to enhance their in vitro antioxidant, α-glucosidase, and α-amylase inhibitory activities. In addition, oxidative stability, hardness, color and sensory properties of fortified muffins were investigated. The fortification of muffin formulations with 6 % hydrolysates increased antioxidant activity six times higher than that of the control sample. As the hydrolysate increased to 6 %, the α-amylase and α-glucosidase inhibition also increased to 88 and 40 %, respectively. The 6 % fortified muffins exhibited lower peroxide and thiobarbituric acid values during a 14 day storage than the control muffins, while higher hydrolysate levels darkened the color and softened the texture. Sensory evaluation indicated that muffins with 2% hydrolysates achieved similar overall acceptance as the control. It can be concluded that brewer's spent grain hydrolysate is suitable for functional bakery products.

Effect of ficin-hydrolyzed wheat gluten on bread quality and in vitro antioxidant activity before and after simulated gastrointestinal digestion

This study aimed to investigate the effect of adding ficin-hydrolyzed wheat gluten at different levels (0%, 1%, 2%, 4%) on bread quality, and in vitro antioxidant activity before and after simulated gastrointestinal digestion. Our findings revealed that the incorporation of the generated wheat gluten hydrolysates (WGH) up to 4 g per 100 g flour positively affected the technological and physical-chemical characterizations of breads, including dough rheological properties, color, specific volume, and moisture. The texture profile analysis indicated reductions in hardness, springiness, and chewiness of the breads, and confirmed anti-staling properties during storage. The enriched breads received satisfactory scores from the sensory panel and were perceived as less stale after a 4-day period of storage. The aroma score of the 4% WGH bread was significantly higher than other treatments. Regarding taste, the 4% WGH bread scored the lowest, but the obtained value was not statistically significant. The enriched breads exhibited DPPH, ABTS radical scavenging, and Fe2+ chelation abilities that increased in response to higher levels of hydrolysate incorporation, and these antioxidant activities were enhanced after simulated gastrointestinal digestion. Our findings confirm that it is possible to apply ficin-generated WGH to enhance physicochemical, nutritional, and biological quality of bread.

Development and quality evaluation of polyphenols enriched black carrot (Daucus carota L.) powder incorporated bread

Black carrot is a prominent source of polyphenols and the cheapest source of anthocyanins in India. In this study, an attempt has been made to examine the feasibility of black carrot powder as an ingredient in bread. Black carrot bread was prepared by incorporating different concentrations of black carrot powder (BCP) at 2.5, 5.0, 7.5 and 10 %. The developed bread samples were analyzed for physical and textural quality, proximate composition, bioactive compounds, antioxidant properties, sensory characteristics, mineral content and storage quality. The results revealed that loaf volume and specific volume decreased (1995-1254 mL, 5.25-3.28 mL/g) with the incorporation of BCP into bread. Textural analysis revealed that the addition of BCP led to increased hardness in the bread (0.110-12 0.151 N), whereas the resilience (43.64-35.10 %), cohesion and springiness (89.930-13 82.146 %) decreased significantly. The content of bioactive compounds such as total phenols, anthocyanins (29.63-112.68 mg/100 g) and flavonoids increased to exceptionally high levels in BCP-incorporated bread and showed high antioxidant activity. Incorporation of BCP up to 7.5 % showed the most acceptable sensory analysis score (7.85) with a significant increase in dietary fiber (40 %) and total mineral content (50 %), which revealed that black carrot powder could be used up to 7.5 % as an ingredient into bread with high acceptability. The present study revealed significant enhancement in bioactive compounds and mineral content of bread after the incorporation of black carrot powder, which supports its immense potential in preventing hunger and oxidative stress-induced disorders in developing countries.

Effects of Wheat Oligopeptide on the Baking and Retrogradation Properties of Bread Rolls: Evaluation of Crumb Hardness, Moisture Content, and Starch Crystallization

Delaying the deterioration of bakery goods is necessary in the food industry. The objective of this study was to determine the effects of wheat oligopeptide (WOP) on the qualities of bread rolls. The effects of WOP on the baking properties, moisture content, and starch crystallization of rolls during the storage process were investigated in this study. The results showed that WOP effectively improved the degree of gluten cross-linking, thereby improving the specific volume and the internal structure of rolls. The FTIR and XRD results showed that the addition of WOP hindered the formation of the starch double helix structure and decreased its relative crystallinity. The DSC results revealed a decrease in the enthalpy change (ΔH) from 0.812 to 0.608 J/g after 7 days of storage with 1.0% WOP addition, further indicating that WOP reduced the availability of water for crystal lattice formation and hindered the rearrangement of starch molecules. The addition of WOP also improved the microstructure of the rolls that were observed using SEM analysis. In summary, WOP is expected to be an effective natural additive to inhibit starch staling and provide new insights into starchy food products.

Unlocking the potential of low FODMAPs sourdough technology for management of irritable bowel syndrome

Consumption of high FODMAP (Fermentable Oligo-, Di-, and Monosaccharides and Polyols) diet is the leading cause of alteration in the human gut microbiome, thereby, causing irritable bowel syndrome (IBS). Therefore, sourdough technology can be exploited for reduction of FODMAPs in various foods to alleviate the symptoms of IBS. Several microorganisms viz. Pichia fermentans, Lactobacillus fetmentum, Saccharomyces cerevisiae, Torulaspora delbrueckii, Kluyveromyces marxianus etc. have been identified for the production of low FODMAP type II sourdough fermented products. However, more research on regulation of end-product and volatilome profile is required for maximal exploitation of FODMAP-reducing microorganisms. Therefore, the present review is focused on utilisation of lactic acid bacteria and yeasts, alone and in synergy, for the production of low FODMAP sourdough foods. Moreover, the microbial bioprocessing of cereal and non-cereal based low FODMAP fermented sourdough products along with their nutritional and therapeutic benefits have been elaborated. The challenges and future prospects for the production of sourdough fermented low FODMAP foods, thereby, bringing out positive alterations in gut microbiome, have also been discussed.

Overview of the Sustainable Valorization of Using Waste and By-Products in Grain Processing

In an increasingly resource-constrained era, using waste and by-products from grain processing has a wide appeal. This is due to the nutritive value and economic aspects of this process and due to its compatibility with the trend towards more sustainable food systems. Following the fundamentals of circular economy, a current need is the effective utilization of grain waste and by-products for conversion into value-added products in the food industry. The aim of this study is twofold: (1) using bibliometrics and the literature found in various databases, we aim to understand the progress of valorizing grain waste and by-products in human nutrition. The literature within various databases, namely, Google Scholar, Web of Science, and Elsevier Scopus, has been evaluated for its merits and values. (2) We aim to explore knowledge-based strategies by reviewing the literature concerning the possible use of grain waste and by-products for the food processing industry, reducing the burden on virgin raw materials. The review allowed us to unlock the latest advances in upcycling side streams and waste from the grain processing industry.

Applications and safety aspects of bioactives obtained from by-products/wastes

Due to the negative impacts of food loss and food waste on the environment, economy, and social contexts, it is a necessity to take action in order to reduce these wastes from post-harvest to distribution. In addition to waste reduction, bioactives obtained from by-products or wastes can be utilized by new end-users by considering the safety aspects. It has been reported that physical, biological, and chemical safety features of raw materials, instruments, environment, and processing methods should be assessed before and during valorization. It has also been indicated that meat by-products/wastes including collagen, gelatin, polysaccharides, proteins, amino acids, lipids, enzymes and chitosan; dairy by-products/wastes including whey products, buttermilk and ghee residue; fruit and vegetable by-products/wastes such as pomace, leaves, skins, seeds, stems, seed oils, gums, fiber, polyphenols, starch, cellulose, galactomannan, pectin; cereal by-products/wastes like vitamins, dietary fibers, fats, proteins, starch, husk, and trub have been utilized as animal feed, food supplements, edible coating, bio-based active packaging systems, emulsifiers, water binders, gelling, stabilizing, foaming or whipping agents. This chapter will explain the safety aspects of bioactives obtained from various by-products/wastes. Additionally, applications of bioactives obtained from by-products/wastes have been included in detail by emphasizing the source, form of bioactive compound as well as the effect of said bioactive compound.

The Rheology and Textural Properties of Bakery Products Upcycling Brewers' Spent Grain

This study aimed to evaluate the rheological properties of doughs with 50% brewers' spent grain (BSG) derived from a rye-based (RBSG) and barley-based (BBSG) beer added, and the textural profile of the related baked products. Simple model systems using BSG flour mixed with water were studied. Two bakery products, focaccia and cookies, were made as food systems using BSG in a 1:1 ratio with wheat flour (WF). Their rheological properties and texture after baking were characterized. BSG-added dough exhibited viscoelastic properties with a solid gel-like behavior. The addition of BSG increased G' > G″ and decreased the dough flexibility. BSG addition in baked RBSG focaccia increased the hardness, gumminess, and chewiness by 10%, 9%, and 12%, respectively. BBSG cookies had a 20% increase in fracturability. A positive correlation was found between the rheological metrics of the dough and the textural parameters of BBSG-added cookies. PCA analysis revealed that complex viscosity, G', G″, and cohesiveness separated BBSG focaccia from RBSG focaccia and the control. Therefore, the rheological properties of BSG dough will have industrial relevance for 3D-printed customized food products with fiber. Adding RBSG and BBSG to selected foods will increase the up-cycling potential by combining techno-functional properties.

Bioactive food-derived peptides for functional nutrition: Effect of fortification, processing and storage on peptide stability and bioactivity within food matrices

New challenges in food production and processing are appearing due to increasing global population and the purpose of achieving a sustainable food system. Bioactive peptides obtained from food proteins can be employed to prevent or pre-treat several diseases such as diabetes, cardiovascular diseases, inflammation, thrombosis, cancer, etc. Research on the bioactivity of protein hydrolysates is very extensive, especially in vitro tests, although there are also tests in animal models and in humans studies designed to verify their efficacy. However, there is very little published literature on the functionality of these protein hydrolysates as an ingredient in food matrices, as well as the effect that thermal or non-thermal processing, and storage may have on the bioactivity of these bioactive peptides. This review aims to summarize the published literature on protein hydrolysates as a functional ingredient including processing, storage and simulated gastrointestinal digestion regarding the bioactivity of these peptides inside food matrices.

Stability and bioactivity of peptides in food matrices based on processing conditions

Bioactive peptides (BPs) generated from food proteins can serve therapeutic purposes against degenerative and cardiovascular diseases such as inflammation, diabetes, and cancer. There are numerous reports on the in vitro, animal, and human studies of BPs, but not as much information on the stability and bioactivity of these peptides when incorporated in food matrices. The effects of heat and non-heat processing of the food products, and storage on the bioactivity of the BPs, are also lacking. To this end, we describe the production of BPs in this review, followed by the food processing conditions that affect their storage bioactivity in the food matrices. As this area of research is open for industrial innovation, we conclude that novel analytical methods targeting the interactions of BPs with other components in food matrices would be greatly significant while elucidating their overall bioactivity before, during and after processing.

Effects of different storage temperatures and time on frozen storage stability of steamed bread

BACKGROUNDS

This research intended to explore the effects of different frozen storage temperatures and time on the stability of steamed bread. The quality characteristics, moisture content and microstructure of steamed bread were determined after quick-frozen for 30 min at -32 °C and frozen storage at -6, -12, -18, -24 and -30 °C for 1-4 weeks.

RESULTS

When the frozen storage temperature is lower, the moisture content, specific volume, pH and the strong bound water in the steamed bread increase, the water loss rate and the contents of freezable water, the weak bound water and free water decreased. With the extension of frozen storage time, the pH value and water loss of steamed bread first increased and then decreased, while the trend of water content was opposite. The specific volume, cohesion and elasticity of steamed bread decreased, while the freezable water content, hardness and chewiness increased. The bound water of steamed bread gradually migrated to free water. In addition, the longer the frozen storage time and the higher the temperature, and the more serious the damage to the microstructure was.

CONCLUSION

The shelf life of steamed bread frozen storage at -12 °C could be up to 3 weeks, and the quality of steamed bread stored at -30 °C for more than 3 weeks was the best. © 2022 Society of Chemical Industry.

Recent Advances in In Vitro and In Vivo Studies of Antioxidant, ACE-Inhibitory and Anti-Inflammatory Peptides from Legume Protein Hydrolysates

Consumption of legumes has been shown to enhance health and lower the risk of cardiovascular disease and specific types of cancer. ACE inhibitors, antioxidants, and synthetic anti-inflammatories are widely used today; however, they have several undesirable side effects. Thus, researchers have focused on finding ACE inhibitors, antioxidant, and anti-inflammatory peptides from natural sources, such as legumes. Recently, in vitro and in vivo research has shown the bioactive peptides generated from legume protein hydrolysates, such as antioxidant, anti-hypertensive, anticancer, anti-proliferative, anti-inflammatory, etc., in the context of different disease mitigation. Therefore, this review aims to describe the recent advances in in vitro and in vivo studies of antioxidant, anti-hypertensive and anti-inflammatory peptides isolated from legume-derived protein hydrolysates. The results indicated that antioxidant legumes peptides are characterized by short-chain sequence amino acids and possess anti-hypertensive properties by reducing systolic blood pressure (SBP) in spontaneously hypertensive rats (SHR).

Relation of amino acid composition, hydrophobicity, and molecular weight with antidiabetic, antihypertensive, and antioxidant properties of mixtures of corn gluten and soy protein hydrolysates

New mixed Alcalase-hydrolysates were developed using corn gluten meal (CP) and soy protein (SP) hydrolysates, namely CPH, SPH, SPH30:CPH70, SPH70:CPH30, and SPH50:CPH50. Amino acid profile, surface hydrophobicity (H ₀), molecular weight (MW) distribution, antioxidant activity, angiotensin-converting enzyme (ACE), α-amylase, and α-glucosidase inhibitory activities, and functional characteristics of hydrolysates were determined. Hydrolysis changed the amount of hydrophilic and hydrophobic amino acid composition and significantly increased the H ₀ values of hydrolysates, especially for CPH. The DPPH radical scavenging activity (RSA) was higher for CPH, SPH30:CPH70, and SPH50:CPH50 than SPH and SPH70:CPH30. Moreover, SPH, SPH70:CPH30, and SPH50:CPH50 showed lower MW than CPH, and this correlated with the higher hydrophilicity, and ABTS and hydroxyl RSA values obtained for SPH and the mixed hydrolysates with predominantly SPH. SPH70:CPH30 exhibited higher ACE, α-glucosidase, and α-amylase inhibitory activities among all samples due to its specific peptides with high capacity to interact with amino acid residues located at the enzyme active site and also low binding energy. At 15% degree of hydrolysis, both SPH and CPH showed enhanced solubility at pH 4.0, 7.0 and 9.0, emulsifying activity, and foaming capacity. Taken together, SPH70:CPH30 displayed strong antioxidant, antihypertensive, and antidiabetic attributes, emulsifying activity and stability indexes, and foaming capacity and foaming stability, making it a promising multifunctional ingredient for the development of functional food products.

Insight into the effect of garlic peptides on the physicochemical and anti-staling properties of wheat starch

The staling of wheat starch in storage seriously damages the quality of starch-based foods, and how to delay the staling has become a topic focus. To solve the problem, this study analyzed the effect of garlic peptides on the physical and retrogradation behaviors of wheat starch during storage. The rheological, pasting, swelling properties, molecular order, water migration, and microstructure of wheat starch gels were evaluated. Our results showed that garlic peptides effectively reduced the storage and loss modulus of wheat starch. The physical properties indicated that garlic peptides suppressed the swelling and gelatinization of starch, which exhibited higher water holding capacity and lower water migration. In addition, garlic peptides incorporated wheat starch exhibited the lowest gel hardness during storage. X-ray diffraction and Fourier Transform Infrared Spectroscopy analysis indicated that garlic peptides could reduce the crystallinity and inhibit the formation of ordered structures in wheat starch gel. The microstructure observation showed that the gel with garlic peptides maintained the integrity of the network structure. Consequently, garlic peptides are expected to be an effective natural additive to inhibit starch staling and provide new insights for starch-based foods.

Protein Ingredients in Bread: Technological, Textural and Health Implications

The current lifestyle and trend for healthier foods has generated a growing consumer interest in acquiring bread products with a better nutritional composition, primarily products with high protein and fiber and low fat. Incorporating different protein sources as functional ingredients has improved the nutritional profile but may also affect the dough properties and final characteristics of bread. This review focuses on the incorporation of different animal, vegetable, and mixed protein sources, and the percentage of protein addition, analyzing nutritional changes and their impact on dough properties and different texture parameters, appearances, and their impact on bread flavor and health-related effects. Alternative processing technologies such as germination and sourdough-based technologies are discussed. Using fermented doughs can improve the nutritional composition and properties of the dough, impacting positively the texture, appearance, flavor, and aroma of bread. It is essential to innovate alternative protein sources in combination with technological strategies that allow better incorporation of these ingredients, not only to improve the nutritional profile but also to maintain the texture and enhance the sensory properties of the bread and consequently, increase the effects on consumer health.

Recent application of protein hydrolysates in food texture modification

The demand for clean labels has increased the importance of natural texture modifying ingredients. Proteins are unique compounds that can impart unique textural and structural changes in food. However, lack of solubility and extensive aggregability of proteins have increased the demand for enzymatically hydrolyzed proteins, to impart functional and structural modifications to food products. The review elaborates the recent application of various proteins, protein hydrolysates, and their role in texture modification. The impact of protein hydrolysates interaction with other food macromolecules, the effect of pretreatments, and dependence of various protein functionalities on textural and structural modification of food products with controlled enzymatic hydrolysis are explained in detail. Many researchers have acknowledged the positive effect of enzymatically hydrolyzed proteins on texture modification over natural protein. With enzymatic hydrolysis, various textural properties including foaming, gelling, emulsifying, water holding capacity have been effectively improved. It is evident that each protein is unique and imparts exceptional structural changes to different food products. Thus, selection of protein requires a fundamental understanding of its structure-substrate property relation. For wider applicability in the industrial sector, more studies on interactions at the molecular level, dosage, functionality changes, and sensorial attributes of protein hydrolysates in food systems are required.

Mechanism of effect of endogenous/exogenous rice protein and its hydrolysates on rice starch digestibility

The role of endogenous/exogenous rice protein and its hydrolysates in the enzymatic hydrolysis resistance of rice starch was investigated. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and Fourier transform infrared spectroscopy (FTIR) results showed that different types of rice endogenous proteins retarded the digestion of rice starch by the same way. Exogenous addition of protein hydrolysates was more effective than protein for impeding starch digestion. FTIR results indicated that rice protein hydrolysates were bound to starch granules through hydrogen bonds, and their interaction strengthened the ordered structure of the starch. Further, the intensity of the starch V- type peak was enhanced after the addition of protein hydrolysates, indicating that some peptides or free amino acids released by the protein formed complexes with the starch, thereby contributing to high slowly-digestible starch content. These findings provide a theoretical basis for the preparation of low glycemic index starch-based foods.

Amaranth selective hydrolyzed protein influence on sourdough fermentation and wheat bread quality

Amaranth selective hydrolyzed protein (ASPH) may improve sourdough properties and bread quality. In this regard, this study focused on investigating the influence of protein hydrolysates on sourdough fermentation and bread properties. Based on the findings, ASPH further increased Lactobacillus plantarum and Saccharomyces cerevisiae growth in sourdough compared with amaranth protein isolates and amaranth flour. ASPH at 5 g/kg resulted in sourdough with higher pH and total titratable acidity (TTA) after 20 h of fermentation at 30°C. The prepared sourdough using APH (S-ASPH) at 3 g/kg increased the specific volume (4.57 ml/g) and TTA (4.76 ml) while decreasing water activity, hardness, cohesiveness, and chewiness of the bread (S-ASPH-B) compared with the control. Moreover, transition temperature and enthalpy reduced whereas sensory properties and shelf life represented an increase with S-ASPH addition. Overall, the obtained data indicated the improvement of bread quality by S-ASPH sourdough.