Enzymatic and enzyme-physical modification of citrus fiber by xylanase and planetary ball milling treatment

Modulating flavanone compound for reducing the bitterness and improving dietary fiber, physicochemical properties, and anti-adipogenesis of green yuzu powder by enzymatic hydrolysis

Yuzu (Citrus junos Sieb.) is a peel-edible fruit with a pleasant aroma, but its bitter taste can impact consumer appeal. In this study, an efficient enzymatic method reduced bitterness in green yuzu powder (GYP). Cellulase KN and naringinase from Aspergillus oryzae NYO-2 significantly decreased naringin and neohesperidin content by over 87 %, while increasing total dietary fiber and soluble dietary fiber by up to 10 % and 51 %, respectively. Insoluble dietary fiber decreased by up to 22 %. Cellulose, hemicellulose, lignin, and pectin contents in enzyme-treated YP decreased by 1.15-2.00-fold, respectively. Enzyme-treated GYP exhibited improved physicochemical properties, including enhanced solubility, oil-holding capacity, and water swelling capacities. 3T3-L1 cells treated with cellulase-treated GYP and naringinase-treated GYP showed lower lipid accumulation and higher lipolysis capability than GYP, along with decreased fatty acid synthase contents. These findings suggest that enzyme-treated GYP holds potential as a functional ingredient in the food industry.

Modification, biological activity, applications, and future trends of citrus fiber as a functional component: A comprehensive review

Citrus fiber, a by-product of citrus processing that has significant nutritional and bioactive properties, has gained attention as a promising raw material with extensive developmental potential in the food, pharmaceutical, and feed industries. However, the lack of in-depth understanding regarding citrus fiber, including its structure, modification, mechanism of action, and potential applications is holding back its development and utilization in functional foods and drugs. This review explores the status of extraction methods and modifications applied to citrus fiber to augment its health benefits. With the aim of introducing readers to the potential health benefits of citrus fibers, we have placed special emphasis on their regulatory mechanisms in the context of various conditions, including type 2 diabetes mellitus, cardiovascular disease, obesity, and cancer. Furthermore, this review highlights the applications and prospects of citrus fiber, aiming to provide a theoretical basis for the utilization and exploration of this valuable resource.

Characterization of bamboo shoots dietary fiber modified by ball milling and its role in altering the physicochemical properties of shrimp surimi

A simple but robust strategy of ball milling (20 Hz, 30 Hz for 30 s, 60 s, 120 s, 180 s) was utilized to modify bamboo shoots fiber (BSDF) in shrimp surimi. The water holding capacity, swelling capacity, and oil binding capacity of 30 Hz-60 s milled BSDF exhibited the highest values of 5.61 g/g, 3.13 mL/g, and 6.93 g/g, significantly higher (P < 0.05) than untreated one (3.65 g/g, 2.03 mL/g, 4.57 g/g). Ball-milled BSDF exhibited a small-sized structure with the relative crystallinity decreased from 40.44 % (control) to 11.12 % (30 Hz-180 s). The myosin thermal stability, gelation properties of surimi were significantly enhanced by incorporating 20 Hz-120 s and 30 Hz-60 s BSDF via promoting protein unfolding, covalent hydrophobic interactions, and hydrogen bonding. A matrix-reinforcing and water entrapping effect was observed, exhibiting reinforced networks with down-sized water tunnels. However, BSDF modified at 180 s contributed to over-aggregated networks with fractures and enlarged gaps. Appropriate ball-milled BSDF (20 Hz-120 s, and 30 Hz-60 s) resulted in a significant decrease in α-helix (P < 0.05), accompanied by an increase of β-sheets and β-turn. This work could bring some insights into the applications of modified BSDF and its roles in the gelation of surimi-based food.

Effect of structural characteristics on the physicochemical properties and functional activities of dietary fiber: A review of structure-activity relationship

Dietary fibers come from a wide range of sources and have a variety of preparation methods (including extraction and modification). The different structural characteristics of dietary fibers caused by source, extraction and modification methods directly affect their physicochemical properties and functional activities. The relationship between structure and physicochemical properties and functional activities is an indispensable basic theory for realizing the directional transformation of dietary fibers' structure and accurately regulating their specific properties and activities. In this paper, since a brief overview about the structural characteristics of dietary fiber, the effect of structural characteristics on a variety of physicochemical properties (hydration, electrical, thermal, rheological, emulsifying property, and oil holding capacity, cation exchange capacity) and functional activities (hypoglycemic, hypolipidemic, antioxidant, prebiotic and harmful substances-adsorption activity) of dietary fiber explored by researchers in last five years are emphatically reviewed. Moreover, the future perspectives of structure-activity relationship are discussed. This review aims to provide theoretical foundation for the targeted regulation of properties and activities of dietary fiber, so as to improve the quality of their applied products and physiological efficiency, and then to realize high value utilization of dietary fiber resources.

Stabilization of emulsions prepared by ball milling and cellulase treated pomelo peel insoluble dietary fiber: Integrity of porous fiber structure dominates the stability

Emulsion gels from the pomelo peel insoluble dietary fiber (PIDF) were developed. The emulsification potentials of PIDFs subjected to various degrees of ball milling (M-PIDFs), cellulase hydrolysis (C-PIDF), and cellulase hydrolysis followed by ball milling (CM-PIDFs) were evaluated. Emulsions prepared by M-PIDFs for different lengths of ball milling time exhibited similar stability characteristics, confirming that M-PIDF emulsion stability might be determined by the three-dimensional structure formed by M-PIDF stacking and oil droplet capture. C-PIDF had characteristics resembling those of Pickering particles. CM-PIDF emulsions got destabilized with ball milling time prolongation. Interface tension and particle size of C/CM-PIDF decreased gradually during ball milling. Rheological and fluorescence microscopy results revealed that the intact internal crosslinking structure frameworks were disrupted in CM-PIDF emulsions. Therefore, intact fiber-based networks, rather than small particle size or low interfacial tension, determine the stability of PIDF emulsions. This study deepens the understanding of PIDF as a clean emulsifier.

Fabrication and characterization of dual-functional porous starch with both emulsification and antioxidant properties

Starchy materials with good antioxidant, emulsification and adsorption properties have potential applications in industry. To improve these properties, a Dual-functional porous starch was prepared through one-pot synthesis. In this case, octenyl succinic anhydride (OSA) and syringic acid (SA) were selected to modify the porous starch (PS) by esterification, with subsequent signals recorded by 1H NMR at 1.2 ppm and FT-IR at 1743 cm-1, indicating the formation of Dual-functional porous starch grafted by OSA and SA. N2 adsorption analysis further proved that the porous structure (2.9 m2g-1) was still maintained after modification. This was followed by measurements of droplet size distribution (34.18 ± 3.80 μm), zeta potential (-39.62 ± 1.89 mV) and emulsion index (85.10 ± 1.76 %), all of which indicated good emulsifying capacity. Meanwhile, results of radical scavenging assay proved that the Dual-functional porous starch had considerable antioxidant properties due to the introduction of SA groups. Besides, the Dual-functional porous starch also showed good resistance to digestion. These findings not only provide a novel strategy for constructing multi-functionalized starchy materials, but also open up potential applications of starch in the food and pharmaceutical industries.

Quality attributes and functional properties of whole wheat bread baked from frozen dough with the addition of enzymes and hydrocolloids

BACKGROUND

The increased demand for healthy and standardized bread has led to a demand for an efficient and promising dough improver, of natural origin, to reduce the deterioration of whole wheat bread baked from frozen dough caused by the high levels of dietary fiber and by freezing treatment. In this study, the combined effects of xylanase (XYL), lipase (LIP), and xanthan gum (XAN) on the quality attributes and functional properties of whole wheat bread baked from frozen dough were evaluated.

RESULTS

The optimal combination, which contained XYL (0.12 g kg-1 ), LIP (0.25 g kg-1 ), and XAN (3.1 g kg-1 ), was obtained using response surface methodology (RSM). The addition of the optimal combination endowed frozen dough bread with a higher specific volume, softer texture, better brown crumb color, and greater overall acceptability. The optimal combination had no adverse impact on the volatile organic compounds (VOCs) of frozen dough bread. In terms of the functional properties of bread, the water-holding capacity (WHC), oil-holding capacity (OHC), and swelling capacity (SWC) of dietary fiber in frozen dough bread decreased in the presence of the optimal combination, whereas the glucose adsorption capacity (GAC) did not affect them. Correspondingly, the in vitro digestive glucose release was not significantly different between the control group and the optimal combination group after frozen storage.

CONCLUSION

The optimal combination could improve the quality attributes and functional properties of whole wheat bread baked from frozen dough effectively, thereby increasing consumption. © 2023 Society of Chemical Industry.

Emulsification Characteristics of Insoluble Dietary Fibers from Pomelo Peel: Effects of Acetylation, Enzymatic Hydrolysis, and Wet Ball Milling

To improve the application potential of pomelo peel insoluble dietary fiber (PIDF) in emulsion systems, acetylation (PIDF-A), cellulase hydrolysis (PIDF-E), and wet ball milling (PIDF-M) were investigated in this paper as methods to change the emulsification properties of PIDF. The impact of the methods on PIDF composition, structure, and physicochemical properties was also assessed. The results demonstrated that both acetylation modification and cellulase hydrolysis could significantly improve the emulsification properties of PIDF. The emulsions stabilized with PIDF-A and PIDF-E could be stably stored at 25 °C for 30 d without phase separation at particle concentrations above 0.8% (w/v) and had higher storage stability: The D4,3 increments of PIDF-A- and PIDF-E-stabilized emulsions were 0.98 μm and 0.49 μm, respectively, at particle concentrations of 1.2% (w/v), while the storage stability of PIDF-M-stabilized emulsion (5.29 μm) significantly decreased compared with that of PIDF (4.00 μm). Moreover, PIDF-A showed the highest water retention capacity (21.84 g/g), water swelling capacity (15.40 mL/g), oil retention capacity (4.67 g/g), and zeta potential absolute (29.0 mV) among the PIDFs. In conclusion, acetylation modification was a promising method to improve the emulsifying properties of insoluble polysaccharides.

Comparative study on chemical composition, functional properties of dietary fibers prepared from four China cereal brans

Comparison of chemical composition and functional properties of insoluble and soluble dietary fiber (IDF, SDF) obtained from four China cereal brans was investigated. With findings, IDFs and SDFs for rice bran (RB), wheat bran (WB), highland barely bran (HBB) and tartary buckwheat bran (TBB) contained several monosaccharides such as arabinose, galactose, glucose, xylose, and galacturonic acid. The RBIDF was shrinking and formed a rugged microscopic structure, while the structure of WBIDF was dense and flat. HBBIDF and TBBIDF showed fold and flake structure. The glucose adsorption capacity of the HBBIDF was highest among all samples, which was 3.2 mmol/g. TBBIDF exhibited the highest value of cholesterol adsorption capacity (10.5 mg/g) at pH 7.0 and maximum binding capacity (BCmax, 365.2 μmol/g) for cadmium at pH 7.0 among all samples, respectively. As a result, HBBIDF and TBBIDF are potential fiber-rich ingredients in functional foods.

A combination of commercial and traditional food-source-derived enzymatic treatment acts as a potential tool to produce functional yuzu (Citrus junos) powder

Enzymatic modifications have been applied in citrus to enhance their physicochemical and biological properties and reduce their bitterness. Notwithstanding, research on the combination of enzyme treatment of yuzu is lacking. In this study, yuzu was treated with a combination of isolated cellulase NY203, pectinase UF, and cellulase KN, and this enzymatic treatment was found to increase monosaccharide, naringenin, and hesperetin levels. In contrast, dietary fiber, cellulose, hemicellulose, lignin, and pectin levels were decreased. Moreover, the enzymes disintegrated the inner and outer surface structures and chemical bonding of yuzu, thus improving its solubility rate, water-holding capacity, oil-adsorption capacity, cholesterol-binding capacity, and water-swelling capacity. Furthermore, NY203 + UF + KN combination treatment reduced the bitterness of treated yuzu by 50 % compared with the control. Additionally, NY203 + UF + KN treatment yielded a 28 % decrease in lipid accumulation and two-fold higher lipolytic activity in 3T3L-1 adipocytes. These findings are potentially beneficial to the food/nutraceutical industries regarding functional yuzu powder production.

Optimization of Chemical Extraction Conditions of Dietary Fiber from Cistanche deserticola Residues and Its Structural Characteristics and Physicochemical and Functional Properties

Cistanche deserticola residues are by-products of the industrial production of Cistanche deserticola, which are currently often discarded, resulting in the waste of resources. In order to achieve the efficient utilization of Cistanche deserticola, dietary fiber from Cistanche deserticola residues was extracted chemically and the optimization of the extraction conditions was performed, using the response surface methodology to study the effects of the NaOH concentration, extraction temperature, extraction time, and solid-liquid ratio on the yield of water-soluble dietary fiber (SDF). The structural, physicochemical, and functional properties of the dietary fiber were also investigated. The results showed that the optimal conditions were as follows: NaOH concentration of 3.7%, extraction temperature of 71.7 °C, extraction time of 89.5 min, and solid-liquid ratio of 1:34. The average yield of SDF was 19.56%, which was close to the predicted value of 19.66%. The two dietary fiber types had typical polysaccharide absorption peaks and typical type I cellulose crystal structures, and the surface microstructures of the two dietary fiber types were different, with the surface of SDF being looser and more porous. Both dietary fiber types had good functional properties, with SDF having the strongest water-holding capacity and the strongest adsorption capacity for nitrite, cholesterol, sodium cholate, and glucose, while IDF had a better oil-holding capacity. These results suggest that Cistanche deserticola residues are a good source of dietary fiber and have promising applications in the functional food processing industry.

Flavonoid Extracts from Lemon By-Products as a Functional Ingredient for New Foods: A Systematic Review

This systematic review seeks to highlight, from the published literature about the extraction and application of lemon by-products rich in flavonoids, which works use environmentally friendly technologies and solvents and which ones propose a potentially functional food application, according to the Sustainable Development Goals (SDGs). WoS and SCOPUS were used as scientific databases for searching the documents, which were evaluated through 10 quality questions according to their adherence to our purpose (5 questions evaluating papers devoted to lemon flavonoid extraction and 5 concerning the application of such by-products in new foods). Each question was evaluated as "Yes", "No", or "does Not refer", according to its adherence to our aim. The analysis reported 39 manuscripts related to lemon flavonoid extraction; 89% of them used green technologies and solvents. On the other hand, 18 manuscripts were related to the incorporation of lemon by-products into new foods, of which 41% adhered to our purpose and only 35% evaluated the functionality of such incorporation. Conclusively, although the bibliography is extensive, there are still some gaps for further investigation concerning the extraction and application of lemon by-products to reduce food losses in an environmentally friendly way and the possible development of new functional foods, which must be performed following the SDGs.

Polysaccharide-based biosorbents for cholesterol and bile salts in gastric-intestinal passage: Advances and future trends

Cholesterol is one of the hazard elements for many cardiovascular diseases, but many cholesterol-lowering drugs are expensive and unhealthy. Therefore, it is necessary to develop edible and safe biosorbents to reduce excess cholesterol and bile salts in the gastric-intestinal passage. Polysaccharide-based biosorbents offer a feasible strategy for decreasing them. This review summarized polysaccharide-based biosorbents that have been developed for adsorbing cholesterol and bile salts from the gastric-intestinal passage and analyzed common modification methods for these adsorbents. Finally, the adsorption models were also elucidated. Polysaccharides, including β-cyclodextrin, pectin, chitin/chitosan, dietary fiber extract, and cellulose, have been proposed for adsorbing cholesterol and bile salts in the gastric-intestinal passage as biosorbents. This is mainly due to the retention of pores, the capture of the viscosity network, and the help of hydrophobic interactions. In spite of this, the adsorption capacity of polysaccharides is still limited. Therefore, the modifications for them became the most popular areas in the recent studies of in vitro cholesterol adsorption. Chemical approaches namely grafting, (1) acetylation, (2) hydroxypropylation, (3) carboxymethylation, and (4) amination are considered to modify the polysaccharides for higher adsorption ability. Moreover, ultrasonic/microwave/pressure treatment and micron technology (microfluidization, micronization, and ball milling) are effective physical modification methods, while the biological approach mainly refers to enzymatic hydrolysis and microbial fermentation. The adsorption models are generally explained by two adsorption isotherms and two adsorption kinetics. In sum, it is reckoned that further food applications will follow soon.

Characterization and the cholesterol-lowering effect of dietary fiber from fermented black rice (Oryza sativa L.)

Black rice was fermented with Neurospora crassa, after which the dietary fiber (DF) extracted from it was characterized and evaluated for its cholesterol-lowering effect in mice. The findings demonstrated that fermentation increased the level of soluble DF from 17.27% ± 0.12 to 29.69% ± 0.26 and increased the adsorption capacity of DF for water, oil, cholesterol, glucose and sodium cholate. The fermented DF had a more loose and porous structure than that extracted from unfermented rice. Additionally, feeding with DF from the fermented black rice significantly reduced body weight, lowered total cholesterol levels and improved the lipid profile in mice gavaged with a high dose (5 g per kg bw) or a low dose (2.5 g per kg·bw). ELISA showed that the hepatic expression of typical proteins and enzymes that are involved in cholesterol metabolism was regulated by the fermented rice DF, leading to reduced cholesterol production and increased cholesterol clearance. The fermented DF also modified the gut microbiota composition (e.g. Firmicutes reduced and Akkermansia increased), which promoted the production of short-chain fatty acids. In conclusion, fermentation can modify the structure and function of DF in black rice and the fermented dietary fiber has excellent cholesterol lowering effects possibly by cholesterol adsorption, cholesterol metabolism modulation, and intestinal microflora regulation.

The effect of ball milling on the structure, physicochemical and functional properties of insoluble dietary fiber from three grain bran

The effects of ball milling processing on the structure, physicochemical, and functional properties of insoluble dietary fiber (IDF) in bran from prosomillet, wheat and rice were investigated. Meanwhile, the effect of IDF on glucose tolerance and blood lipid levels in mice was evaluated as well. With findings, for all three grains, the particle sizes of IDF were significantly reduced after ball milling treatment (p < 0.05). Scanning electron microscopy revealed fragmented fiber with numerous pores and cracks. The reactive groups of three IDF samples were found to be similar by fourier transform infrared spectroscopy. And consistent with X-ray diffraction and thermal analysis, for all three grains, ball milling reduced the crystallinity of IDF and helped to increase the release of free phenol by 23.4 %, 8.9 %, and 12.2 %, respectively. Furthermore, the water holding capacity, glucose delay capacity, glucose, sodium cholate, and cholesterol adsorption capacity, and in vitro digestibility of starch and fat were all improved to varying degrees. Animal experiments showed that ball milling treatment effectively slowed the postprandial rise in blood sugar (especially IDF of rice bran) and blood lipids (especially IDF of prosomillet bran). As a result, ball milling treatment is a potential method for dietary fiber modification in the food industry.

Effects of shear emulsifying/ball milling/autoclave modification on structure, physicochemical properties, phenolic compounds, and antioxidant capacity of lotus (Nelumbo) leaves dietary fiber

Lotus (Nelumbo) leaves are rich in polyphenols and dietary fiber, which have the potential as a high-quality fiber material in functional food. However, lotus leaves exhibit dense structure and poor taste, it is vital to develop appropriate modification methods to improve the properties of lotus leaves dietary fiber. In this study, the effects of three modification methods with shear emulsifying (SE), ball milling (BM), and autoclave treatment (AT) on structure, physicochemical properties, phenolic compounds, and antioxidant capacity of lotus leave dietary fiber (LDF) were evaluated. SEM indicated that there were significant differences in the microstructure of modified LDFs. FT-IR spectra and X-ray diffraction pattern of modified LDFs revealed similar shapes, while the peak intensity and crystalline region changed by modification. SE showed the greatest effect on crystallization index. SE-LDF had the highest water holding capacity, water swelling capacity, and bound phenolic content in LDFs, which increased by 15.69, 12.02, and 31.81%, respectively, compared with the unmodified LDF. BM exhibited the most dramatic effect on particle size. BM-LDF had the highest free phenolic and total phenolic contents in LDFs, which increased by 32.20 and 29.05% respectively, compared with the unmodified LDF. Phenolic compounds in LDFs were mainly free phenolic, and modifications altered the concents of flavonoids. The BM-LDF and SE-LDF exhibited higher antioxidant capacity than that of AT-LDF. Overall, SE-LDF showed better physical properties, and BM-LDF showed better bioactive components. SE and BM were considered to be appropriate modification methods to enhance the properties of LDF with their own advantages.

Integrated Technology for Cereal Bran Valorization: Perspectives for a Sustainable Industrial Approach

Current research focuses on improving the bioaccessibility of functional components bound to cereal bran cell walls. The main bioactive components in cereal bran that have major biological activities include phenolic acids, biopeptides, dietary fiber, and novel carbohydrates. Because of the bound form in which these bioactive compounds exist in the bran matrix, their bioaccessibility is limited. This paper aims to comprehensively analyze the functionality of an integrated technology comprising pretreatment techniques applied to bran substrate followed by fermentation bioprocesses to improve the bioaccessibility and bioavailability of the functional components. The integrated technology of specific physical, chemical, and biological pretreatments coupled with fermentation strategies applied to cereal bran previously-pretreated substrate provide a theoretical basis for the high-value utilization of cereal bran and the development of related functional foods and drugs.

Comparison and Characterization of the Structure and Physicochemical Properties of Three Citrus Fibers: Effect of Ball Milling Treatment

Effects of ball milling (BM) on the structure and physicochemical properties of three types of citrus fibers were investigated. With the extension of the grinding time, the particle size of citrus fibers significantly decreased. Fourier transform infrared spectroscopy (FTIR) showed that the three citrus fibers had similar chemical groups, and more -OH and phenolic acid groups were exposed after BM, and pectin and lignin were not degraded. Scanning electron microscope (SEM) results showed that the appearance of particles changed from spherical to fragmented, irregular shapes. The water holding capacity (WHC), oil holding capacity (OHC), and water swelling capacity (WSC) of citrus fibers LM, JK, and FS reached the maximum value after BM of 2 h (increasing by 18.5%), 4 h (increasing by 46.1%), and 10 h (increasing by 38.3%), respectively. After 10 h BM, citrus fibers FS and JK had the highest adsorption capacity of cholesterol and sodium cholate, increasing by 48.3% and 48.6%, respectively. This indicates that BM transforms the spatial structure of citrus fibers and improves their physicochemical properties.

Enzymes-Assisted Extraction of Plants for Sustainable and Functional Applications

The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.