• Food Science and Biotechnology
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• v.18 no.2
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• pp.356-361
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• 2009

Lipid oxidation and contents of tocopherols and phospholipids (PL) in soy-added fried products during storage in the dark were studied. Flour dough containing soy flour at 0, 10, 20, and 30% on a weight basis was fried in corn oil at $180^{\circ}C$ for 2.5 min. The fried products were stored at $60^{\circ}C$ for 11 days in the dark. Lipid oxidation of the fried products was evaluated by conjugated dienoic acid (CDA) and p-anisidine values (PAV). Tocopherols and PL were determined by high performance liquid chromatography (HPLC). CDA contents and PAV of the fried products were increased during storage, and addition of soy flour improved lipid oxidative stability of the fried products, which was partly related to increased amount of tocopherols and PL in the soy-added fried products. Tocopherols and PL were degraded during the dark storage of the fried products. Soy flour addition to the dough did not affect the rate of tocopherols degradation during storage of the fried products; however, PL degradation was higher in the soy-added fried products. Residual amounts of $\alpha$-tocopherol and phosphatidylinositol showed high correlations with the lipid oxidation of the fried products during storage in the dark.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.549-556
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• 2007

The study was carried out to examine on the refiner discharge from Alaska pollock as a collagen resource by characterizing biochemical and functional properties of collagen. The refiner discharge from Alaska pollock surimi manufacturing was a good resource for collagen extraction according to the results of total protein, heavy metal, volatile basic nitrogen, collagen content, amino acid composition, and thermal denaturation temperature (TDT). TDT of acid soluble collagen from refiner discharge showed $20.7^{\circ}C$, which was similar to that of collagen from Alaska pollock muscle and was higher than that of collagen from Alaska pollock skin. TDT of acid-soluble collagen from refiner discharge was, however, lower than those of skin collagens from warm fish and land animal. Acid-soluble collagen from refiner discharge of Alaska pollock could be used as a functional ingredient for food and industrial applications according to the results of water and oil absorption capacities, and emulsion properties. In addition, if the thermal stability of the acid-soluble collagens is improved, collagen from refiner discharge from Alaska pollock could be more effectively used.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.615-620
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• 2007

Commercially packed kimchi products from 6 different manufacturers, which are exported overseas as well as sold domestically, were analyzed to determine their microorganism distributions and presence of pathogenic bacteria. All samples showed decreasing pH levels (from 5.7-6.2 to 3.9-4.3) and increasing titratable acidities (from 0.3-0.4 to 0.8-1.2%) during 15 days of storage at $4^{\circ}C$. Total bacterial counts ranged from $2.1{\times}10^5-1.9{\times}10^6\;CFU/mL$ in the initial kimchi samples, and then increased to $1.1{\times}10^8-1.8{\times}10^9\;CFU/mL$. The coliform numbers decreased from approximately $2.5{\times}10^2-1.7{\times}10^4\;CFU/mL$ to zero. Major foodborne pathogens such as Salmonella spp., Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes, Bacillus cereus, Yersinia enterocolitica, and Shigella spp. were not detected in any of the samples. However, 2 out of the 6 samples carried E. coli, emphasizing the need for improved hygiene practice. Interestingly, Hafnia alvei, belonging to the Enterobacteriaceae family, was isolated in all of the samples. Further study is needed on this newly reported bacterium in kimchi.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1011-1018
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• 2015

The effects of mixing speed (3, 6 and 10 speed) and time (2, 5 and 10 min) on the dynamic viscoelasticity of dough and the baking properties of gluten-free rice bread were investigated. The specific gravity of the dough was not affected by the mixing speed and time before and after fermentation. The elasticity (G') and viscosity (G") of the dough increased and the tan ${\delta}$ (G"/G') decreased with higher mixing speeds and longer mixing times. The specific volume of the gluten-free rice bread was affected by the mixing time in response surface methodology (RSM). The hardness of the gluten-free rice bread showed a decreasing trend as the specific volume for the gluten-free rice bread increased. The appearance of the gluten-free rice bread was symmetrical at high mixing speeds and long mixing times. Overall results indicated that the quality of gluten-free rice bread could be improved by controlling the mixing speeds and mixing times for the dough.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.274-284
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• 2012

In this study, the effects of physical parameters (30-270 MPa of pressure, 3-57 min of time, and 1-$49^{\circ}C$ of temperature) on pork quality were investigated. Response surface methodology was used in order to monitor and model the changes in pork quality under varied pressure conditions. As quality characteristics, shear force, water holding capacity (WHC) and the CIE color of pork were measured, and optimum pressure conditions were evaluated by statistical modeling. Pressure improved the WHC of pork at relatively low temperature ($<25^{\circ}C$); however, the opposite occurred with increasing temperature. Although pressure and temperature affected the tenderness of the meat, interaction effects among variations were not observed. At pressure levels higher than 200 MPa, the color of pork differed markedly from that of the untreated controls. In particular, differential scanning calorimetry (DSC) revealed marked evidence of myosin denaturation. The present study demonstrates that pork quality varies depending on pressure conditions.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.131-136
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• 2016

This study was conducted to investigate the effects of chicory fiber for the replacement of fat and smoking on quality characteristics of restructured sausages. Treatments were as follows; Control: Pork backfat 20%, T1: Pork backfat 10% + Chicory fiber 10%, T2: Control + Smoking, T3: T1 + Smoking. The addition of chicory fiber significantly reduced the moisture, fat, hardness and pH values, whereas the smoking treatment increased the fat, redness and pH values of restructured sausages (p<0.01). Additionally, interaction of them significantly affected the ash, chewiness and hardness values of restructured sausages. As a result, although the addition of chicory fiber decreased the quality characteristics of sausage, smoking treatment improved the reduced quality. Therefore, the chicory fiber and smoking treatment is helpful to develop restructured sausage products with reduced fat and compensated quality.

• Journal of the Korean Dietetic Association
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• v.16 no.3
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• pp.255-269
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• 2010

The purpose of this study was to investigate consumer awareness and demand related to country-of-origin labeling at restaurants, and to provide basic data to reexamine the need for current policies and to determine problems. The study found that 70% of the respondents thought that the implemented representation policy had improved food quality, and 81.3% of the respondents checked country-of-origin labeling at restaurants. In addition, 74.7% of the respondents answered that "reward for accusation" was appropriate policy. Regarding the degree of recognition of the meat importers, the respondents were well aware of the importing countries, but did not recognize the importing country of chicken. In terms of preference for meat importers, Australian beef was rated highest, but beef from the U.S. was ranked seventh. However, in preferences for pork and chicken, U.S. products were rated highest. According to the survey, in a question regarding the perception toward country-of-origin labeling, the respondents recognized that rice, beef, pork, and chicken were the targeted items. In addition, the respondents suggested that other food ingredients at restaurants should be designated as target items for country-of-origin labeling.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.198-208
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• 2017

Purpose: To improve the quality of basic gluten-free rice bread composed of white rice flour, salt, sugar, yeast, skim milk powder, olive oil, and water, the effects of transglutaminase (TGase), whey protein (WP), propylene glycol alginate (PGA), and hydroxypropylmethylcelluose (HPMC) were investigated. Methods: TGase, WP, PGA, and HPMC were added to rice flour cumulatively. The pasting properties of rice flour blends as well as volume, shape, color value, textural properties and sensory evaluation of basic rice bread (RB1) RB1+TGase (RB2), RB1+TGase+WP (RB3), RB1+TGase+WP+PGA (RB4), and RB1+TGase+WP+PGA+HPMC (RB5) were compared. Results: Consistency of rice batter increased upon addition of TGase, WP and PGA, and RB3 and RB4 had higher specific volumes than others. PGA improved volume, crumb air cell uniformity, and resilience but lowered elasticity and moistness of RB. HPMC increased, hardness, moistness and softness, and slightly reduced volume. Conclusion: Therefore, it is suggested that hydrocolloids, PGA and HPMC may be necessary to improve volume, crumb structure, textural properties and overall eating quality of gluten-free rice bread.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.808-814
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• 2014

This study investigated the effect of gum arabic (GA) combined with microbial transglutaminase (TG) on the functional properties of porcine myofibrillar protein (MP). As an indicator of functional property, heat-set gel and emulsion characteristics of MP treated with GA and/or TG were explored under varying NaCl concentrations (0.1-0.6 M). The GA improved thermal gelling ability of MP during thermal processing and after cooling, and concomitantly added TG assisted the formation of viscoelastic MP gel formation. Meanwhile, the addition of GA decreased cooking yield of MP gel at 0.6 M NaCl concentration, and the yield was further decreased by TG addition, mainly attributed by enhancement of protein-protein interactions. Emulsion characteristics indicated that GA had emulsifying ability and the addition of GA increased the emulsification activity index (EAI) of MP-stabilized emulsion. However, GA showed a negative effect on emulsion stability, particularly great drop in the emulsion stability index (ESI) was found in GA treatment at 0.6 M NaCl. Consequently, the results indicated that GA had a potential advantage to form a viscoelastic MP gel. For the practical aspect, the application of GA in meat processing had to be limited to the purposes of texture enhancer such as restructured products, but not low-salt products and emulsion-type meat products.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.226-231
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• 1996

A serum-pulp method was applied to concentrate peach pulp with aroma recovery. The serum portion was concentrated to five-fold at $50{\sim}55^{\circ}C$ and $30{\sim}50$ mmHg with aroma recovery. The concentrated serum, insoluble pulp and aroma fraction were recombined to make a two-fold concentrated peach pulp. The results of GC and GC/MS analysis for volatile compounds and sensory evaluation of concentrated peach pulp indicated that flavor quality was significantly improved by addition of aroma fractions. A 10% aroma recovery appeared to be appropriate for peach pulp.