Soybean Okara Research Articles

Evaluation of the Digestibility of Diets Containing Soy Okara in Clarias gariepinus (Burchell, 1822) Fries Raised in a Controlled Environment in Benin

Aims: To evaluate the digestibility of diets containing soy okara in Clarias gariepinus fries. Study Design: Random complete block design. Place and Duration of Study: Laboratory of Hydrology and Wetland Research, Faculty of Sciences and technics, University of Abomey-calavi, between June 2019 and July 2019. Methodology: Four diets containing different levels of soy okara (0%, 10%, 20% and 30%) respectively noted T0, T1, T2 and T3 were tested. Twelve 40L tanks were randomly distributed into 04 batches with 03 repetitions for each of the 04 diets. The fries with an initial average weight of 10.47 +/- 2g were fed ad libitum three times a day (8 A.M., 12 P.M., 4 P.M.) for 30 days. Survival rate, cannibalism rate, average daily gain, specific growth rate, weight-length relationship, condition factor, consumption index, ingested protein, protein efficiency coefficient and digestive utilization coefficients were measured. Results: The specific growth rates (SGR) ranged between 2.25 +/- 0.165 and 2.58 +/- 0.115 with the best rate for the treatment containing 0% soy okara. The consumption index varied from 1.18 +/- 0.009 to 1.41 +/- 0.132 with the best index for the T3 treatment. Furthermore, the mortality rates were 0% for treatments containing 20% and 30% soy okara. The results indicate that it is possible to incorporate up to 30% soybean okara into the diet of Clarias gariepinus fry without hindering their zootechnical performance. The digestive protein utilization coefficients of the diets were calculated and are 95.12; 88.47; 92.21 and 90.37 for diets containing 0%, 10%, 20% and 30% soy okara respectively. Conclusion: The results demonstrate that among the different diets tested, treatment T2, containing 20% soy okara, proved to be the most favorable in terms of zootechnical performance. These results suggest that T2 treatment can be considered as a promising option for feeding Clarias gariepinus fries.

Biochemical investigation on symbiotic products of soybean Okara in milk processing

Biochemical investigation on symbiotic products of soybean Okara in milk processing

Impacts of Ultrasonic Treatment for Black Soybean Okara Culture Medium Containing Choline Chloride on the β-Glucosidase Activity of Lactiplantibacillus plantarum BCRC 10357.

The effects of ultrasonic treatment for the culture medium of solid black soybean okara with choline chloride (ChCl) on the survival and β-glucosidase activity of Lactiplantibacillus plantarum BCRC 10357 (Lp-BCRC10357) were investigated. A mixture of 3% dried black soybean okara in de Man-Rogosa-Sharpe (w/v) was used as the Oka medium. With ultrasonic treatment (40 kHz/300 W) of the Oka medium at 60 °C for 3 h before inoculation, the β-glucosidase activity of Lp-BCRC10357 at 12 h and 24 h of incubation amounted to 13.35 and 15.50 U/mL, respectively, which was significantly larger than that (12.58 U/mL at 12 h and 2.86 U/mL at 24 h) without ultrasonic treatment of the medium. This indicated that ultrasonic treatment could cause the microstructure of the solid black soybean okara to be broken, facilitating the transport of ingredients and Lp-BCRC10357 into the internal structure of the okara for utilization. For the effect of ChCl (1, 3, or 5%) added to the Oka medium (w/v) with ultrasonic treatment before inoculation, using 1% ChCl in the Oka medium could stimulate the best response of Lp-BCRC10357 with the highest β-glucosidase activity of 19.47 U/mL in 12 h of incubation, showing that Lp-BCRC10357 had a positive response when confronting the extra ChCl that acted as an osmoprotectant and nano-crowder in the extracellular environment. Furthermore, the Oka medium containing 1% ChCl with ultrasonic treatment led to higher β-glucosidase activity of Lp-BCRC10357 than that without ultrasonic treatment, demonstrating that the ultrasonic treatment could enhance the contact of ChCl and Lp-BCRC10357 to regulate the physiological behavior for the release of enzymes. In addition, the analysis of the isoflavone content and antioxidant activity of the fermented product revealed that the addition of 1% ChCl in the Oka medium with ultrasonic treatment before inoculation allowed a higher enhancement ratio for the biotransformation of isoflavone glycosides to their aglycones, with a slight enhancement in the antioxidant activity at 24 h of fermentation. This study developed a methodology by combining ultrasonic treatment with a limited amount of ChCl to allow the culture medium to acclimate Lp-BCRC10357 and release high levels of β-glucosidase, and this approach has the potential to be used in the fermentation of okara-related products as nutritional supplements in foods.

Effect of ultrasonic treatment on soybean okara to be used as a gluten‐free bread improver

SummaryThe production of soybean protein isolates generates an insoluble residue called okara that is rich in proteins and dietary fibre. These macromolecules have functional properties that can be modified and improved by emerging technologies, such as high‐intensity ultrasound. The objectives of this work were to analyse the ability of soybean okara (UOK) to act as a gluten‐free bread improver and to evaluate the effect of a sonication process on this property (OKS). Both okaras were assayed at two percentages (2% and 3%) leading to a reinforcement of interactions in the matrix of batters, producing bread of better technological and sensorial quality. The addition of OKS 3%, improved specific volume (20%), reduced the hardness (30%) and increased the cohesiveness of the crumb and improved the air inclusion. These results demonstrated the efficiency of the sonication process to obtain a gluten‐free bread improver from a bulky by‐product of the soybean industry.

Soybean okara: Effect of ultrasound on compositional and emulsifying properties

AbstractHigh‐intensity ultrasound is widely used to modify the functional properties of macromolecules (proteins, polysaccharides, etc.) and to expand their range of potential applications. This work is aimed at studying the effects of ultrasound treatments on the composition of different soybean okara samples and their potential as an emulsifying agent. Defatted solvent‐free soybean flour (DSF) was extracted by adjusting dispersion to pH 9.0. Insoluble residues obtained after centrifugation were dried, and an unsonicated okara sample (UOK) was obtained. Furthermore, the soybean flour dispersion was subjected to treatment in a probe‐type ultrasonic homogeniser before or after the alkaline extraction process, thus producing SOK and OKS samples, respectively. The sonication process generated compositional and structural changes in okara soybeans. SOK had higher yield and protein content than UOK and OKS due to the insolubilisation of the glycinin (11S) fraction of soybean storage proteins. Due to these characteristics, the SOK sample showed the best emulsifying activity.

Quality Evaluation of Butter Cake Prepared by Substitution of Wheat Flour with Green Soybean (Glycine Max L.) Okara

ABSTRACT Using byproducts from the food industry to produce healthy and sustainable food was an integral component of the sustainable development goals. This research was aimed to assess the effect of substituting wheat flour with nutrient-rich green soybean okara (GSBO) flour on the quality and nutritional values of butter cake. The result showed that the GSBO-substituted flour had significantly (p ≤ 0.05) higher water and oil absorption capacities, higher protein, fiber and total phenolic content (TPC), and more favorable sensory characteristics compared to wheat flour. Specifically, 20% GSBO butter cake contained significantly (p ≤ 0.05) highest amounts of protein, fiber, TPC, and scores of all sensory characteristics. In conclusion, substitution of up to 20% GSBO to wheat flour could improve the nutritional quality of butter cake. Application of GSBO flour in butter cake contributes to the sustainable goal of achieving zero waste and development of a plant protein-based product in sustainable healthy diet.

Anaerobic co-digestion of textile dyeing sludge: Digestion efficiency and heavy metal stability

Anaerobic co-digestion (AcoD) has become an important mean for the stabilization and recycling of textile dyeing sludge (TDS). Using the soybean okara byproduct (SOB) as a co-digestion substrate, the effects on AcoD performance and heavy metal stability were studied. The results indicated that the optimal mixing ratio was 1:1 (calculated by total sloid). Under this condition, the SCOD removal efficiency was 64% (that of TDS alone and SOB alone were 47% and 48%, respectively) and the cumulative methane production field was 503 L CH4/kg VS (that of TDS alone and SOB alone were 435 L CH4/kg VS and 408 L CH4/kg VS, respectively). At the same time, the addition of SOB could also enhance the stability of heavy metals (Zn, Cu, Cr and Ni) in TDS. Remarkably, that could increase the steady state content nickel from 47.98% to 57.21%, while anaerobic digestion of TDS caused no increase but a decrease (only 42.13%). According to the risk assessment code analyses, the AcoD of TDS by SOB can significantly reduce the ecotoxicity risk caused by Ni, Zn and Cr.

Assessment of the Physicochemical and Conformational Changes of Ultrasound-Driven Proteins Extracted from Soybean Okara Byproduct.

This study was aimed at the valorization of the okara byproduct deriving form soy food manufacturing, by using ultrasound at different temperatures for extracting the residual proteins. The physicochemical and conformational changes of the extracted proteins were investigated in order to optimize the procedure. Increasing the temperature from 20 up to 80 °C greatly enhanced the yields and the protein solubility without affecting the viscosity. The protein secondary and tertiary structures were also gradually modified in a significant way. After the ultrasonication at the highest temperature, a significant morphological transition from well-defined single round structures to highly aggregated ones was observed, which was confirmed by measuring the water contact angles and wettability. After the ultrasound process, the improvement of peptides generation and the different amino acid exposition within the protein led to an increase of the antioxidant properties. The integrated strategy applied in this study allows to foster the okara protein obtained after ultrasound extraction as valuable materials for new applications.

Unconventional recipe component in the production of pasta

The use of secondary raw materials as new recipe ingredients in the production of food products is currently quite relevant. Soybean okara, which is a by-product of soy milk production, may be promising in this case. Special attention is paid to its technological properties and rich chemical formula which includes at least 5.5% of complete protein characterized by the content of all essential amino acids, dietary fiber, unsaturated fatty acids, macro-, microelements (potassium, calcium, magnesium, iron, iodine, etc.), vitamins (β-carotene, E, group B, choline, biotin, folic acid), isoflavones, which suggests the positive effect of the use of okara in food production in order to increase their consumer properties and nutritional value. It is important that soybean okara practically does not have any flavor, which allows to use it in the production of a great variety of food products and culinary. The article proves the possibility to use soybean okara in the production of pasta, gives some optimal drying parameters of soybean okara for its further use, investigates the influence of soybean okara on the properties of raw gluten of wheat flour, rheological characteristics of pasta dough and the quality, first of all, on cooking properties of pasta, determines its rational proportion taking into account the quality of the main raw material (11.5% to flour weight). The content of protein and fiber in the composition of soybean okara and finished pasta is determined.

Drying Applications during Value-Added Sustainable Processing for Selected Mass-Produced Food Coproducts

Developing circular value chains for continuing the use of and reducing the waste of the resources of industrial processing would eliminate impairments to the environment. The generation of nutrient-dense byproducts and coproducts with high-moisture contents are considered to be an issue for global food industries. These byproducts and coproducts spontaneously undergo chemical, biochemical, or microbial deteriorations due to high storage-temperatures, and consequently are turned into direct animal feed sources or even just treated as waste with eutrophication activity. This review provides an overview of selected mass-produced botanical food byproducts and coproducts (BFBC) including soybean okara, wheat germ, banana, and spent coffee grounds, with respect to value-added sustainable processing via proper drying technologies being employed. This review includes the current production of the above-mentioned agricultural products, the nutritional aspects of them, and the sustainable utilization of their coproducts. Additionally, the possible drying kinetics for value-added prospects are discussed.

Impact of high pressure homogenization on physical properties, extraction yield and biopolymer structure of soybean okara

The effect of high pressure homogenization (HPH) on soy okara was studied. To this purpose, okara dispersions (10 g/100 g) were subjected to 1 pass at 50, 100 and 150 MPa and to 5 passes at 150 MPa. Samples were analyzed for stability, particle size, microstructure, and viscosity. Results highlighted that the increase of HPH intensity was associated with the structural disruption of okara particles, leading to physically stable homogenates having increasing viscosity. This was mainly attributed to an increase in okara solubility, due to fibre and protein release. The latter resulted almost complete, reaching values up to 90% of the protein originally entrapped in okara matrix. Absorbance at 280 nm, SH groups and dimension of proteins revealed that HPH treatments favoured the extraction of the main protein fractions even if, at the higher intensity level, extracted proteins probably underwent conformational changes and reassembling phenomena.

Effect of ultrasound on the extraction of bioactive aglycone isoflavones for the green valorization of black soybean residue (okara)

The effect of ultrasound on the extraction of bioactive aglycone isoflavones for the valorization of black soybean okara was investigated. A high extraction efficiency for total isoflavones was achieved with the total isoflavones extracted using water being 77.8% of that using 80% methanol as the solvent. The fraction of bioactive aglycones (daidzein and genistein) in total isoflavones using ultrasound (40 kHz/300 W) for 10 min was 81.7%, and further enhanced to 86.7% for 30 min. The profile of isoflavones was significantly influenced by temperature with the amounts of 351.00 μg/g-okara of aglycones and 91.43 μg/g-okara of glycosides using ultrasound at 60°C for 3 hr, and the fractions of aglycones in isoflavones were 96.4, 89.6, and 79.3% for 35, 50, and 60°C, respectively. An extraction model was proposed to successfully correlate the extraction rate coefficients and the limit concentrations of the four isoflavones in water. Practical applications The bioactive aglycone isoflavones are beneficial for human health. The okara produced from food industries contains high-quality isoflavones, which have to be recovered for the potential use in functional foods. The process developed in this study allows the recovery of high-content aglycone isoflavones from black soybean okara without further biotransformation of glycoside isoflavones, and provides the effective valorization of okara and process sustainability in food applications.

Bio-ionic liquid pretreatment and ultrasound-promoted enzymatic hydrolysis of black soybean okara

The effective processing method to produce fermentable sugars and modify the microstructure of black soybean okara using bio-ionic liquid (bio-IL) pretreatment and ultrasound-promoted enzymatic hydrolysis was investigated. The morphology and structural characteristics of okara before and after bio-IL pretreatment and enzymatic hydrolysis under different ultrasonic frequencies were analyzed by field emission scanning electron microscope (FE-SEM), X-ray energy dispersive spectrometer (EDS), and Fourier transform infrared spectroscopy (FTIR). Without pretreatment, the production of total reducing sugar (TRS) under ultrasound (40kHz/300W) was 3.4 times of that without ultrasound. Using the bio-IL choline acetate ([Ch][OAc]) in water for the pretreatment of black soybean okara, the TRS production of enzymatic hydrolysis was further increased to 5.2 times of that without ultrasound in 4h of reaction. The analysis by FTIR and EDS showed that the highly structured matrix of okara was unfolded and broken by the action of combining ultrasound and choline acetate pretreatment, due to which the surface structures with large pores were presented to facilitate the reduction of unfavorable hindrance for enzymatic hydrolysis. The simplified kinetic model was proposed to describe the transport and reaction phenomena of enzymes in a solid-liquid system by using two kinetic parameters to show the impeded behavior of enzyme within the matrix of okara. The combination of bio-IL pretreatment and ultrasound-promoted enzymatic hydrolysis was able to make the efficient structural changes of black soybean okara to enhance the digestion of enzymes, and the okara could be valorized for use in foods.

Stability of gluten free sweet biscuit elaborated with rice bran, broken rice and okara

A challenge to the food sector has been the development of new products incorporating co-products from the food processing industry with minimal impact on their pre-determined structures and adding nutritional quality. In order to add value and develop alternatives for the use of co-products generated during the agroindustrial processing, this work aimed to study the stability of gluten-free sweet biscuits developed with soybean okara, rice bran and broken rice. The formulations were elaborated with increasing percentages of these ingredients and compared with the standard (commercial sweet biscuit) for ten months. The analyses were: weight, diameters (internal and external), thickness, specific volume, instrumental parameters of color, texture, scanning electron microscopy, water activity, proximal composition and isoflavones. The experimental sweet biscuits had characteristics of color, weight, volume and diameters (internal and external) very similar to the commercial, whereas texture, lipids and energy value decreased, and aw, moisture and protein increased during storage. The sweet biscuits showed the same stability when compared to the standard, and the

Okara Supplementation Relieves Fatigue and Muscle Damage that Occur during Exercise Training

Okara, the soybean residue from soy milk production, contains nutrients and functional components. The objective of this study was to investigate the effect of okara supplementation on fatigue and muscle damage in university athletes over an exercise training season. A total of 23 male university baseball players aged 18-23 years attending a summer intensive exercise training program completed an 8-week exercise training-okara intervention study. The supervised exercise training program consisted of physical and technical training including warm-up exercises, physical and skill practice, and pre-game competition practice. Okara supplementation in this study was a randomized, double-blind and crossover dietary intervention in which subjects consumed 2 cookies/day containing of soybean or black soybean okara for a period of 6 weeks with a one-week washout period. Blood was drawn 4 times within an 8-week intervention period for measurements of biomarkers for fatigue and muscle damage. The results demonstrated significant differences in blood levels of ammonia, free fatty acids, creatine kinase, myoglobin, and aspartate transferase between baseline and exercise training, indicating that fatigue and muscle damage occurred during exercise training. However, those increased markers of fatigue and muscle damage were significantly decreased after the okara supplementation regardless of whether soybean okara or black soybean okara cookies were consumed. This is the first study to demonstrate that okara supplementation is beneficial to university baseball players who experience exercise training-related fatigue and muscle damage. Fatigue and muscle damage occurring during exercise training were both relieved, indicating that okara cookies are feasible sports nutrition supplements.

Optimization of extrusion variables for the production of snacks from by-products of rice and soybean

This study aimed to define the process conditions to obtain snacks from the by-products of rice and soybean with physical characteristics suitable for marketing. Therefore, the effects of moisture and extrusion temperature on the expansion and color of the products obtained experimentally obtained were evaluated, and the proximate composition of the by-products and that of the snack with greater desirability were determined. Response surface methodology and rotational central composite design were used, and desirability test based on the regression models adjusted was applied. The most desirable snack, with the highest expansion index (3.39), specific volume (13.5 mL.g-1), and the chromaticity coordinate a* (2.79), was obtained under 12 g.100 g-1 moisture and 85oC of temperature in the third zone of the extruder. The snack produced under these conditions attained content of protein and lipid content 41 and 64% higher than that of the traditional corn snack. It can be concluded that producing extruded snack made form a mixture of broken grains, rice bran, and soybean okara (81:9:10) is technologically feasible, enabling the development of a new product with good nutritional value that can improve the diet of children, the main consumers of this type of food.

β-Glucosidase Isolated from Soybean Okara Shows Specificity toward Glucosyl Isoflavones

A novel beta-glucosidase was isolated from soybean okara in this study. Along with the beta-glucosidase, a considerable basic 7S globulin of soybean was obtained in the initial extraction products. The protein samples pretreated with 130 mM dithiothreitol before the step of CM-Sepharose chromatography could greatly enhance the separation of the targeted beta-glucosidase from the impurities. The purified beta-glucosidase was found to be a monomer estimated to be 75 kDa by SDS-PAGE. The optimal temperature and pH for this beta-glucosidase were 45 degrees C and 4.5, respectively. The activity of this purified beta-glucosidase was completely inhibited by 1 mM Hg(2+) or 10 mM Al(3+) ion, and glucose and mannose also affected the activity. This beta-glucosidase possessed strict specificity toward glucosyl isoflavones but not malonylglucosidic conjugates of isoflavones of soybean. The N-terminal amino acid sequence of the beta-glucosidase was EYLKYKDPKA-, which highly matched that of glycosidases in maize (Zea mays) and wheat (Triticum asetivum).

Extraction and purification of pectic polysaccharides from soybean okara and enzymatic analysis of their structures

Pectic polysaccharides (6.74 g) were extracted from soybean okara (soybean curd waste, 30 g) with sodium hexametaphosphate solution. The extract was separated by DEAE-cellulose chromatography into galacturonate poor and galacturonate rich fractions. The fractionated polysaccharides were exhaustively degraded by three kinds of pectinase and two kinds of hemicellulase, namely exo- and endopolygalacturonases, exopolygalacturonate lyase, exogalactanase and exoarabinase. The values of the degradation limit revealed that the soybean pectic polysaccharides comprise regions of galacturonan and rhamnogalacturonan carrying side chains composed mainly of homogeneous arabinan and galactan. The galacturonan regions were distributed at both the reducing and nonreducing ends of the polysaccharide.

Effects of Hexametaphosphate on Soybean Pectic Polysaccharide Extraction

The effects of sodium hexametaphosphate concentration, incubation temperature, and pH on the extraction of polysaccharide from soybean okara (soybean curd waste) were examined. The results suggest that the soybean polysaccharides were almost completely extracted with 50 times their volume of a 2% hexametaphosphate solution at 100°C for 2h, avoiding protein contamination. The viscosity, molecular weight, and sugar composition of the polysaccharides were compared with those of the commercially available samples. No differences were observed in the molecular weight or neutral sugar composition. However, it was found that the galacturonate distribution in the molecules of the two polysaccharides was different. The viscosity of the polysaccharide solution was changed by adding small amount of salt.