• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.3
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• pp.511-527
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• 2024

The aim of this study was to impart color to bacterial cellulose (BC) fabric using various natural plant-based dyes-namely, gardenia jasminoides, green tea, and pomegranate peel. A protein pretreatment was also applied to improve the BC fabric's dyeability and mechanical properties. The BC fabric's dyeing and mordanting conditions when using plant-based natural dyes were determined by changes in the K/S values. The dyeability of BC samples dyed with green tea or pomegranate peel improved when they were pretreated with soy protein isolate (SPI) prior to dyeing. Moreover, the SPI pretreatment was efficient in improving the BC fabric's tensile strength and flexibility. This study proposes a method for dyeing BC fabric that uses plant-based natural dyes and confirms the effects of the protein pretreatment on the fabric's dyeability and durability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.751-758
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• 2017

The objective of this study was to determine the effects of moisture content and screw speed on the physical properties of extruded soy protein isolate (SPI). Expansion index, water absorption index, texture, integrity index, color, and nitrogen solubility index of extruded SPI were analyzed to determine the relationship with extrusion conditions. Extrusion conditions were moisture content (40, 50, and 60%) at a fixed die temperature ($140^{\circ}C$) and screw speed (250 rpm). The other extrusion conditions were screw speed (150, 250, and 330 rpm) at a fixed moisture content (55%) and die temperature ($140^{\circ}C$). Specific mechanical energy (SME) input decreased as moisture content increased from 40 to 60%. However, SME input increased as screw speed increased from 150 to 330 rpm. Expansion ratio and piece density decreased as moisture content and screw speed increased, and specific length increased as moisture content and screw speed increased. The extruded SPI at 40% moisture content had higher water absorption index, texture, and color differences than those of the extruded SPI at other moisture contents (50 and 60%). however, the extruded SPI at 40% moisture content had lower integrity index and cutting strength than those of the extruded SPI at other moisture contents (50 and 60%). In conclusion, the physical properties of extruded SPI were more affected by moisture content than screw speed.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.676-681
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• 2001

This study was carried out to evaluate the quality characteristics of frozen soy yogurts prepared with different proteolytic enzymes and starter culture. The viable cell counts of lactic acid bacteria in frozen soy yogurts were measured $10^8$ CFU/g by the single culture method, while $10^9$ CFU/g by the mixed culture method except ${\alpha}-chymotrypsin$ treatment. The viable cell counts of lactic acid bacteria did not decrease after freezing for 30 min in ice cream maker. The lactic acid bacteria from the mixed culture showed better bile acid tolerance than those from the single culture. The lactic acid bacteria from the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of Bifidobacterium bifidum and Lactobacillus bulgaricus showed better acid tolerance and bile acid tolerance. The highest(73.45%) overrun was observed in the frozen soy yogurt treated with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus. The melt-down percent was higher in the single culture than the mixed culture. In sensory test, the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1209-1223
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• 2009

In this review, the terminology that is used to describe ileal amino acid (AA) digestibilities in piglet feed ingredients is defined. If one accepts that the determination of AA digestibilities should be based on the ileal analysis method, one should consider that ileal digesta contains variable amounts of endogenous crude protein (CP), which originates mainly from digestive secretions, sloughedoff epithelial cells and mucins. The ileal endogenous CP and AA losses are separated into basal ileal endogenous CP and AA losses ($IAAL_{B}$), which are not influenced by the feed ingredient composition, and specific ileal endogenous CP and AA losses ($IAAL_{S}$), which are induced by feed ingredient characteristics such as level and type of fiber and anti-nutritional factors (ANF). Depending how ileal endogenous CP and AA losses are considered in the measurement of CP and AA digestibilities, digestibility values are expressed as apparent (AID), standardized (SID), or true (TID) ileal digestibilities of CP and AA. The main concern associated with the use of AID values in diet formulation for pigs is that they are not additive in mixtures of feed ingredients. Consequently, the concept of standardized ileal CP and AA digestibilities was introduced by correcting AID values for basal ileal endogenous CP and AA losses ($IAAL_{B}$). The correction for both $IAAL_{B}$ and $IAAL_{S}$ yields TID values, however, routine procedures to measure $IAAL_{S}$ are not yet available. In principle, SID values should be preferred, because they represent the fundamental properties of the feed ingredient. There exist only few reports on SID of CP and AA in feedstuffs frequently used in piglet nutrition. These include soybeans (SB), soybean meal (SBM), soy proteins (SP), soy protein concentrate (SPC), soy protein isolate (SPI), corn gluten (CG), wheat gluten (WG), pea protein (PeaP), potato protein (PotP), fish meal (FM) and whey proteins (WP), but the results obtained are inconsistent. Differences in SID values within feed ingredients may, at least in part, be attributed to different processing conditions or inherent differences of the assay feed ingredients. Moreover, there is some evidence that the determination of SID values and $IAAL_{B}$ in piglets may be confounded by the dietary CP level of the assay diet, age and (or) body weight (BW), the level of feed intake or the methodological approach used to determine $IAAL_{B}$.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.577-582
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• 2002

Effects of the addition of single or blends of konjac flour (KF), carrageenan (CN), and soy protein isolate (SPI) into the sausage formulation were determined based on the physico-chemical and textural characteristics of low-fat comminuted sausage (LFS, fat <3%). LFSs had a pH range of 6.10 to 6.16, 77-79% moisture, <3% fat, and 13-15% protein contents, whereas regular-fat sausages (RFSs) had a pH value of 6.11, 62.5% moisture, 19.4% fat, and 11.9% protein. LFSs containing fat replacers were reduced (P<0.05) cooking loss (CL, %). KF alone or mixed with other hydrocolloids slightly improved the water-holding capacity, whereas CN increased (P<0.05) the gel strength, resulting in higher hardness values. Replacement of 6% lean meat with 1.5% SPI alone increased (P<0.05) yellowness (Hunter b value) and expressible moisture (EM, %). TPA values of KF+CN+SPI were the most similar to those of RFSs. These results indicated that triple addition of KF, CN and SPI at the ratio of 1 : 1 : 3 in LFS formulation improved functional properties, as compared to the low-fat control, and had textural characteristics most similar to those with RFSs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.25-45
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• 1996

Soyfoods have potential roles in the prevention and treatment of chronic diseases, most notably cancer, osteoporosis, and heart disease. There is evidence that carcinogenesis are supressed by isolated soybean derived products in vivo such as a protease inhibitor, phytic acid, saponins and isoflavones. It is believed that supplementation of human diets with soybean products markedly reduces human cancer mortality rates. Especially, recent papers recognize the potential benefit of soybean isoflavone components for reducing the risk of various cancers. Isoflavones exhibit a multitude of medicinal effects that influence cell growth and regulation, which may have potential value in the prevention and treatment of cancer. In addition to potential biological effects, soybean isoflavones have the important physiological functions such as the induction of Bradyrizobium japonicum nod genes and the responses of soybean tissues to infection by Phytophthora megasperma as well as biochemical activities such as antifungal and antibacterial actions. Genistin, daidzin, glycitin and their aglycone (genistein, daidzein, glycitein) are the principal isoflavones found in soybean. Malonyl and acetyl forms have also been detected but they are thermally unstable and are usually transformed during the processing in glucoside form. Most soy products, with the exception of soy sauce, alcohol-extracted soy protein concentrate, and soy protein isolate, have total isoflavone concentrations similar to those in the whole soybean. Soybean-containing diets inhibit mammary tumorigenesis in animal models of breast cancer, therefore, it is possible that dietary isoflavones are an important factor accounting for the lower incidence and mortality from breast cancer. Of the total soybean seed isoflavones, $80\~90\%$ were located in cotyledons, with the remainder in the hypocotyls. The hypocotyls had a higher concentrations of isoflavones on a weight basis compared with cotyledons. Isoflavone contents were influenced by genetics, crop years, and growth locations. The effect of crop year had a greater impact on the isoflavone contents than that of location. The climate condition might be the attribution factor to variation in isoflavone contents. Also, while the isoflavone content of cotyledons exhibited large variations in response to high temperature during seed development, hypocotyls showed high concentration in isoflavone content. So, it is concluded that one of the factors affecting isoflavone content in soybean seeds is temperature during seed development. High temperature, especially in maturity stage, causes lower isoflavone content in soybean seed. It is also suggested that there may exist a different mechanism to maintain isoflavone contents between cotyledon and seed hypocotyls. In a conclusion, soy foods may be able to have a significant beneficial impact on public health.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.36-41
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• 2010

The Hen's egg is widely used in many processed foods as an ingredient and is one of the most prevalent food allergens in children. To detect egg proteins in processed foods, we developed a competitive indirect enzyme-linked immunosorbent assay (ciELISA) using an anti-ovomucoid (OM) antibody, which was produced by immunization of rabbits with OM, the most heat-stable component of the egg proteins. The detection limit of this quantitative assay system was 30 ng/mL. Cross-reactivity of the anti-OM antibody toward OM, ovalbumin, skim milk, casein, whey protein isolate, and isolated soy protein was 100, 0.4, 0.2, 0.04, 0, and 0%, respectively. In the spike test of egg white powder in milk replacer, commercial sausage, and in-house sausage, the assay recoveries ($mean{\pm}SD$) were $129{\pm}13.7%$, $73.9{\pm}12.5%$, and $65.5{\pm}13.6%$, respectively. When egg white in a commercial crab meat analog and sausage was determined by ciELISA, the assay recovery was found to be 108% and 127%, respectively. The combined results of this study indicate that this novel ciELISA for OM detection could be applied for the quantification of hen's egg proteins in processed foods.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.278-283
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• 2003

Textural properties of tofu manufactured with micronized full-fat soyflour (MFS) were enhanced by the addition of soy protein isolate, whey protein concentrate, chitosan oligosaccharide and mushroom powder. The MFS solution (14.2% solid content) was converted to semi-solid tofu by a two-stage heat treatment with the addition of 4% coagulant mix. The MFS tofu was evaluated by a compression test as well as sensory evaluation. To produce the semi-solid gel (MFS tofu) with reasonably high strength and toughness, the MFS solution with 14.2% solid content and 7.0% protein had to be heat treated at 121$^{\circ}C$ for 3min. The relative toughness of MFS tofu was increased by the addition of SPI, showing a 144% increase. The toughness of MFS tofu prepared with the MFS/SPI mixture was greatly increased by the addition of WPC at the level of 0.7% and the water separation from MFS tofu was greatly reduced. Furthermore, the toughness and strength of MFS/SPI tofu was enhanced by the addition of 0.1% chitosan oligosaccharide and 0.2% mushroom powder. The sensory evaluation of the tofu fortified with SPI, chitosan oligosaccharide and mushroom powder was superior to that of MFS tofu, with a higher score for overall preference.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.794-798
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• 1995

Deamidation by neutrase on glutaminyl and asparaginyl residues of protein was examined. The optimum pH and temperature for BSA(bovine serum albumin) deamidation by neutrase were 10 and $20^{\circ}C$, respectively. The incubation for 3 hrs under the optimum condition removed 24% of amide groups and hydrolyzed 2.9% of peptide bonds. Deamidation by neutrase was superior to that by pronase, bromelain, or ficin. Deamidation degrees of egg albumin, soy protein isolate and casein by neutrase under the optimum condition were about 20%, 14% and 14%, respectively. However, relatively high degree of peptide hydrolysis was accompanied with casein deamidation.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.772-778
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• 2015

Hydrolysis of isolate soybean protein (ISP) using subcritical water (SCW) was conducted to study the feasibility for producing protein hydrolyzate. SCW hydrolysis of SPI suspension (5-15%) was conducted in an electrically heated batch reactor (2 L). The effects of temperature (230 to $270^{\circ}C$) and holding time (10 to 50 min) on the degree of hydrolysis (DH) and the production of amino acids were studied by surface response method. The DH was determined by derivatizing the hydrolyzates with ortho-phthalaldehyde (OPA) solution. It was confirmed that reaction temperature and holding time affected the hydrothermolysis of soybean protein. However, the holding time was less effective on amino acid yield when the temperature was higher than $230^{\circ}C$. In order to achieve optimal yields of amino acids exceeding 43%, the temperature should be within the range between 256 and $268^{\circ}C$ with holding time from 29 to 41 min, respectively. A maximum estimated amino acid yield of 43.5% was obtained at $268^{\circ}C$ for 35 min.