• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.562-566
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• 2005

Effects of amino acids (Arg, Lys, Gly, Ile, Glu, Asp, and Met) on the color intensity, stability and antioxidative properties of anthocyanins extracted from grape skins were investigated. Intensity of anthocyanins was significantly increased by the addition of Asp. Except for basic amino acids such as Arg and Lys, stabilities of anthocyanins were significantly improved by the addition of other amino acids including neutral, acidic and sulfur containing amino acids during the storage at $30^{\circ}C$ at pH 3.5. In case of control anthocyanins was remained unchanged the intensity of red color decreased significantly during the storage whereas their antioxidative activity were unchanged. Although effects of amino acids addition on electron donating abilities of anthocyanins were not differentiated by DPPH (2,2-diphenyl-1-picrylhydrazyl) method, the addition of Asp or Met resulted in increased ferric reducing ability which measured by FRAP (ferric reducing ability of plasma) assay.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.231-234
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• 2000

To evaluate the effect of frying times on the oxidative stability of soybean oil and shortening, they were reused up to 10 times and measured by thiobarbituric acid(TBA) value, acid value(AV), peroxide value(POV) and sensory evaluation. As the reusing time was increased, TBA value of "battered pork" fried with shortening showed more sharply increased than that with soybean oil, while the value of shortening, itself, showed more decreased than that of soybean oil. In frying fat, AV and POV increased with the increase of reusing times. Compared with soybean oil, shortening had rapidly increased for POV as reusing time was increased. Among the sensory analyses TBA of "battered pork" with soybean oil and shortening exhibited the highest correlation with flavor and texture, respectively. For the "batgtered pork" fried with soybean oil and shortening, reusing shelf-lives predicted were approximately 9 and 8 times, respectively.

• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.195-208
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• 2013

The purpose of this study was to evaluate the quality characteristics of chicken sausage prepared with turmeric (Curcuma longa L.) powder (T) during storage at $4^{\circ}C$ for 20 days. The pH and color values (a and b values) of sausage containing turmeric powder were significantly higher (P<0.05) than the control for both uncooked and cooked sausage. The hardness, chewiness, and gumminess of control sausage significantly changed after 15 days of storage, while the hardness and gumminess of turmeric-supplemented sausages (T) significantly increased after 5 days (until 15 days) for cooked sausages. The total phenolic content and DPPH radical scavenging activity of turmeric-supplemented sausages was significantly higher (P<0.01) than the control for both uncooked and cooked sausage during storage. On the other hand, the acid value of the control was higher than the turmeric-supplemented sausages and the peroxide value of the control was significantly higher (P<0.05) than the turmeric-supplemented sausages after 15 days of storage. Microorganism analysis revealed that total plate counts of uncooked and cooked control sausages were significantly higher (P<0.05) than turmeric-supplemented sausages at 20 days of storage. As a result, sausages prepared with turmeric powder demonstrate antioxidative activity and lipid oxidative stability during storage.

• Food Science of Animal Resources
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• v.40 no.1
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• pp.55-73
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• 2020

Poultry meat is generally exposed to quality deterioration due to lipid oxidation during storage. Oxidative stability of meat can be increased by feed supplementation. Aim of the current study was to investigate the effect of dietary supplementation of fish waste derived bioactive peptides on antioxidant potential of broiler breast meat and physico-chemical characteristics and quality parameters of nuggets prepared from breast meat. 180 broiler birds (six groups of 30 birds) were purchased. Each group was given different concentrations of bioactive peptides i.e. 0, 50, 100, 150, 200, and 250 mg/kg feed. After completion of six weeks birds were slaughtered and breast meat was stored at -18℃ for six months. Nuggets were prepared and stored at -18℃ for 45 days. Meat samples were analyzed for antioxidant activity [total phenolic contents (TPC), DPPH^· scavenging activity, and ferric reducing antioxidant power] and lipid oxidation assay at regular intervals of 1, 2, 3, 4, 5, and 6 months while nuggets were analyzed for quality (pH, color, texture and water holding capacity) parameters after regular interval of 15 days. A significant (p<0.05) effect of feed supplementation was observed on antioxidant status such as TPC, DPPH^· scavenging activity, and FRAP of broiler breast meat. Dietary interventions of bioactive peptides significantly (p<0.05) delayed lipid oxidation of breast meat than control. All the quality parameters were also significantly affected due to dietary bioactive peptides and storage duration. Thus, dietary interventions of bioactive peptides can increase the antioxidant and shelf stability of broiler breast meat and nuggets.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.369-377
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• 2007

The aims of this study were to develop and standardize the manufacturing procedures and ingredient formulation of non-fried, extrusion-puffed Yukwa. The quality and storage stability of the non-fried Yukwa (NF) were characterized and compared against a traditional deep-fried Yukwa (F). The moisture contents of both the NF and F were almost comparable at 5.12${\sim}$6.22% after the final product preparation. The textural hardness values of the NF samples were one-half to two times as hard as those of F, although no clear distinctions were reported between the two products by the sensory evaluation results (p<0.05). During storage, the acid value of F was 1.68 KOH mg/g on day 7, and then it rapidly increased to 5.52 KOH mg/g on day 14. In contrast, the acidity values of NF were 1.21 and 2.62 KOH mg/g on day 7 and 14, respectively. The peroxide values of the samples increased from 23.5 to 62.0 meq/kg (F) and from 2.0 to 2.5 meq/kg (NF) during the two weeks of storage after preparation, suggesting excellent fat stability for the NF product. Regarding the sensory evaluation results of the products, no significant (p<0.05) differences were noted between F and NF with scores of approximately 3.1 out of 5.0 points for the overall quality characteristics of the final products. Accordingly, we conclude that extrusion puffing technology could be adopted as an alternative to conventional deep fat frying as a partial manufacturing process of Yukwa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.519-524
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• 1992

purified rapeseed(Brassica napus var. Youngsan) protein was hydrolyzed by pronase. The hyrolysate protein was investigated for the some physicochemical and functional properties. UV and intrinsic fluorescence spectra of the hydrolysate showed the maximum absorption at 274nm and 360nm respectively. Intensity of yellow color decreased in the process of hydrolysis and the surface hydrophobicity decreased up to fourfold. The main bands of hydrolysate by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) were observed at 14,000 to 12,000 dalton molecular weight. Solubilities of hydrolyzed protein increased by 10~15% compared to those of unhydrolyzed protein at acidic pH. In the hydrolysate, while absorption of both water and oil, foam expansion and emulsion stability were increased, absolute viscosity, heat coagulation, calcium coagulation, foam stability and emulsion activity were decreased.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.405-412
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• 2015

To develop a color stable and fine bamboo leaf powder (BLP) as a functional green biomaterial, bamboo leaf (BL) purchased from Sasa borealis and cultivated in Damyang, Jeonnam was treated with different conditions and BLP was evaluated. The four treatments comprised of boiling in water, in zinc chloride, sodium bicarbonate, and vinegar solutions, BLP4 was treated with 2% $ZnCl_2$ for 1 h, BLP5 was treated with 1% $ZnCl_2$ for 2 h, and BLP6 was treated with 1% $ZnCl_2+10%$ NaCl for 1 h. The particle size distribution, ash content, water binding capacity, and color change after heating in acidic solution were compared to commercial fine green tea (GTP) and bamboo leaf powders (CBLP). The particle size (cumulative 90%) of BLP was finest in BLP4 followed by BLP6 < BLP5 < GTP < CBLP. The water binding capacity of GTP was the highest and that of BLP was negatively correlated with particle size. After heating in acidic solution, the color of commercial GTP and CBLP changed from bright green to olive green, but the treated BLPs remained bright green. Especially, the -a (greenness) values for the commercial powders decreased from 11.2-13.6 to 3.1-3.8, while those of the treated BLPs did not change.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.280-285
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• 2018

Lipid oxidation and antioxidant stabilities of nut-sesame yeotgangjeong (Korean traditional candy bar) with different binders were evaluated during storage in the dark. S1, S2, and S3 binders consisted of starch syrup, sugar, and water (58:34:7.6, w/w/w); starch syrup, jocheong, honey, trehalose, and water (43.5:11.6:2.9:34:7.6, w/w/w/w/w); and starch syrup, jocheong, honey, sugar, trehalose, and water (43.5:11.6:2.9:17:17:7.6, w/w/w/w/w/w); respectively. Lipid oxidation was determined by peroxide and p-anisidine values, and tocopherol, lignan, and polyphenol contents were determined spectrophotometrically. Peroxide values were significantly higher (p<0.05) in yeotgangjeong samples with S2 or S3 binder than in those with S1; however, the converse was true for tocopherol degradation. Lignan was the most stable antioxidant in yeotgangjeong. The results suggest that tocopherols have a priority over lignans to control the lipid oxidation of yeotgangjeong during storage; reduced lipid oxidative stability after substituting sugar with trehalose might be because it increases oxygen diffusivity and inhibits the antioxidant action of tocopherols on lipids.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.499-506
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• 2008

This study was conducted to determine the quality characteristics of grape jellies for the elderly. The jellies contained sugar (control) or sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol). Agar (0.31%) and $\kappa$-carrageenan (0.27%) were the gelling agents. The average age of the subjects participating in the acceptance test was 79. The lightness (L), redness (a), and yellowness (b) values of the agar gel with erythritol mostly decreased, indicating a darker and pale red color. The L and b values of the carrageenan gel with sugar derivative sweeteners increased, indicating brighter and yellowish color. The agar and carrageenan gels with sorbitol showed higher gelling and melting temperature, indicating that gelation occurred easily and did not easily melt. The agar and carrageenan gels with xylitol showed a low-melting temperature, indicating low stability with temperature change. The break-down rate of the agar and carrageenan gels with erythritol was low, whereas that of agar gel with sorbitol was relatively high despite its high melting temperature. Hardness, cohesiveness, gumminess, and chewiness of the gels with sugar derivative sweeteners decreased, and this tendency was most distinct with isomaltooligosaccharide in the agar gel and with sorbitol in the carrageenan gel. The rupture properties of the gel were the same as the hardness of the gel. Sensory acceptance of the agar gels with erythritol, sorbitol, isomaltooligosaccharide, and the carrageenan gel with erythritol was fairly high, whereas that of the agar gel with xylitol and the carrageenan gel with isomaltooligosaccharide and xylitol was low. The results show that sorbitol and erythritol are appropriate as sugar substitutes in grape jellies for the elderly about the acceptability and stability of the gels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.964-972
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• 1994

The 4.3-kb gene coding for L-lactate dehydrogenase of Bacillus stearothermophilus has been subcloned and expressed in E. coli cells. The enzyme was purified 200-fold with 25% yield by heat treatment , DEAE-Sephadex, and NAD++ -Sepharose CL-4B affinity chromatography followed by gel filtration through Sephadex G-200 . The molecular weight of the purfied enzyme was estimated to be about 35, 000 and 140, 000 on SDS-polyacrylamide gel electrophoresis and gel filtration, respectively. indicating that the enzyme is composed of four identical subunits. THe enzyme for pyruvate reduction and lactate oxdiation was stable at 60 and 75$^{\circ}C$ for 30 min, and the optimal temperatures for both reactions were 60 and 7$0^{\circ}C$, respectively. The enzyme had an optimal pH at 5.5 and 8.5 in pyruvate reduction and lactate oxidation, respectively. The pH stability of enzyme of pyruvate reduction was table between pH 5 and 7. more than 90% of enzyme activity was lost at 1mM FeSO4 and p-chloromercuribonzoate. The maximal activation of the enzyme was obtained with 0.8mM fructose 1, 6-bisphosphate.