• Korean Journal of Food Science and Technology
• /
• v.37 no.5
• /
• pp.812-815
• /
• 2005

Effects of poly-${\gamma}$-glutamate (PGA) on antioxidative characteristics of amino-carbonyl reaction products of glucose were investigated. Rapid browning reaction was observed under heat and alkaline condition (pH 8.2). Browning products were separated by Sephadex G-50, and brown color intensity and electron-donating ability of DPPH (2,2-diphenyl-1-picrylhydrazyl) of each fraction were measured. Fraction-7 (F-7) and -20 (F-20) showed high DPPH scavenging values. UV-VIS absorption spectrum of F-20 was similar to melanoidin peak, and F-7 showed maximum absorption peak at 270 nm. Molecular weight of F-7 was over 35 kDa as determined by SDS-PAGE. Although F-20 could not be measured on SDS-PAGE, its size was smaller than F-7.

• Journal of Nutrition and Health
• /
• v.21 no.4
• /
• pp.197-212
• /
• 1988

To study the effect of preventing the browning reaction between casein and glucose by protecting the reactants using corn starch with coating material, rats were fed for 30 days nonbrowning diet, nonprotected browning diet, browning diet protected only casein, browning diet protected both casein and glucose and browning diet supplement sucrose simultaneously with protecting both casein and glucose. The amounts of fructosyl-lysine excreted through urine were greater than those through feces regardless of diets and the both side of the excreted amounts of fructosly-lysine through urine or feces were greater for rats fed browning diets regardless protecting compared to rats fed the nonbrowning diet. Through urine, the excreted amounts of fructosyl-lysine were decreased for rats fed the browning diet supplemented sucrose simultaneously with protecting both casein and glucose than those for rats fed the nonprotected browning diet and through feces, were decreased for rats fed protected browning diets regardless of protecting method than the nonprotected browning diet. The excreted amounts of all individual essential free amino acids through feces were increased for rats fed browning diets irrespective of protecting compared to the nonbrowning diet, but through urine, were increased or similar level for rate fed the nonbrowning diet compared to browning diets except histidine. The excreted amount of free lysine through feces were decreased for rats fed protected browning diets than nonprotected browning diet. Fructosyl-lysine contents of serum, liver and small intestinal digesta were increased for rats fed browning diets regardless of protecting by starch compared to nonbrowning diet but, of serum and small intestinal digesta were decreased for rats fed protected browning diets than the nonprotected browning diet.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.2
• /
• pp.143-152
• /
• 1989

Some sugars and proteins were mixed with yellow corvenia lipids, soybean lipids or see yolk lipids to study the influence of the sugars or proteins on lipid oxidation and browning in dry and wet system during kept at $40^{\circ}C$. In the yellow corvenia lipids mixed with various food components, peroxide value(POV), carbonyl value(COV) and brown pigments were much higher than the case that soybean lipids or egg folk lipids were mixed. In terms of the food components, they appealed high in glucose, sucrose and starch but low in albumin and casein. When the soybean lipids were mixed, POV appeared low in all these maxture. COV and brown pigments appeared high in glucose, sucrose and starch but low in albumin and casein. In the case of egg york lipids, POV appeared lower than that of soybean lipids but COV and brown pigments were similar. In the starch mixture of three lipids in wet system, POV and COV in yellow corvenia lipids appealed lower, but appeared higher in soybean lipids and egg yolk lipids than those in dry system. Brown pigments appeared similarly with the case in dry system. And the all mixtures of casein in wet system, POV and COV appealed lower thanthose of the dry system, but brown pigments appeared high.

• Korean Journal of Food Science and Technology
• /
• v.32 no.5
• /
• pp.979-984
• /
• 2000

To improve the quality of dehydrated onion, antibrowning agents were screened. Effects of antibrowning agents on the degree of browning and the quality characteristics in dried onions were investigated. Sliced onions were dehydrated in an air drier at $70^{\circ}C$ within 3 percent moisture. Among various antibrowning agents, cyclodextrin and corn starch treatments were selected. Dipping in 4%(w/v) corn starch suspension proved more effective in preventing browning than other treatments. The change of color and the degree of browning showed a correlation. Dried onions treated with antibrowning agents prevented browning at around $24{\sim}32%$ compared to control. The contents of reducing sugar and vitamin C in treated onions had minimally changes.

• Food Science and Preservation
• /
• v.10 no.1
• /
• pp.11-15
• /
• 2003

Various quality characteristics of minimally processed mushroom were measured to select appropriate browning inhibitor. The treatment of extracts from Asparagi radix, cassia and kiwi on mushrooms have a high effectiveness like ascorbic acid or cysteine, known as a good chemical antibrowning agent. As a results of physical quality characteristics of minimally processed mushroom during storage, 1% cysteine and Asparagi radix were highly effective on degree of browning. Total phenol content and polyphenol oxidase activity showed slight differences among the mushroom treated with each browning inhibitors, but it has gradually increased during storage. Thus, these results suggest browning inhibitors from natural materials can be alternatives to prevent browning on mushrooms instead of chemical browning inhibitors including ascorbic acid or cysteine, has been widely used for antibrowning agent.

• Korean Journal of Food Science and Technology
• /
• v.19 no.5
• /
• pp.446-450
• /
• 1987

To re-evaluate the browning reactions of fermented soybean products, soy sauce mash with added glucose and/or tyrosine was fermented for 152 days in the presence or absence of oxygen. Glucose negatively affected brown pigmentation either singly or with tyrosine. Tyrosine-added soy sauce mash initially browned at the same rate as the control mash until 127th day and then the former continued to brown at the same steady rate while the control mash stopped further browning. Aerobically incubated mash browned much more than anaerobically incubated one when the browning was compared on the 152nd day of fermentation. More than half of the mash browning was found to be due to the oxygen-related browning during the limited 152 days of fermentation time. Both oxygen-related and oxygen-unrelated browning reactions were found to contribute to the browning of soy sauce mash. Oxygen-related browning, however, was found to be more important than the Maillard browning reaction.

• Korean Journal of Food Science and Technology
• /
• v.38 no.4
• /
• pp.554-561
• /
• 2006

The objective of this study was to investigate the effects of browning inhibitors during fermentation and storage of rice-grape wine. Bentonite, polyvinylopolypyrrolidone (PVPP), and potassium metabisulfite were added to rice-grape wine during fermentation and storage in order to find an effective method of inhibiting browning. Total phenolics content, pH, amino acidity, hydroxymethylfurfural content, and absorbance at 420 nm were measured during storage to assess the effects of the different browning substrates. Potassium metabisulfite was the most effective browning inhibitior. Sensory evaluation also showed that rice-grape wine treated with potassium metabisulfite was highly Preferable in terms of color, taste, flavor, and overall quality.

• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.1
• /
• pp.70-73
• /
• 2004

The browning rate of potato juice alone and potato juice with added carrot juice or water(1:1 by volume) were studied. As the amount of carrot juice added was increased, the browning rate proportionally decreased: from 1.86 of potato juice alone to 0.36 for the potato juice and carrot juice mixture(l:1). This inhibitory effect of carrot juice on browning led us to assume that $\beta$-carotene, the major constituent of carrot carotenoids, may be involved in impeding the browning reaction of potato juice. Therefore, model system of enzymatic browning, consisting of chi orogenic acid/tyrosine and $\beta$-carotene/carrot carotenoids, were studied. The results shows the browning rates of chlorogenic acid alone and chlorogenic acid with added $\beta$-carotene. The initial browning rate of chlorogenic acid was faster($\delta$L= 1.1/min.)than that of chlorogenic acid with added $\beta$-carotene($\delta$L=0.6/min.).

• Korean Journal of Food Science and Technology
• /
• v.25 no.3
• /
• pp.214-219
• /
• 1993

Properties of the antioxidative fraction isolated from browning reaction product (BRP) that were obtained from 2 M L-ascorbic acid (AsA) solution (adjusted to pH 7.0) by heating for 25 hrs at $85^{\circ}C$ were investigated. Both of dialyzable and nondialyzable fraction isolated from BRP showed antioxidative effect. Dialyzable fraction has stronger antioxidative activity than nondialyzable. Dialyzable fraction was divided into the three fractions (A, B, C) by gel filtration. Among these fractions, the fraction (A) that had the highest reducing power and lowest browning drgree had lowest antioxidative activity. The fraction (C) that had lowest reducing power and highest browning degree showed strongest antioxidative effect. In the UV-visible spectrum of these fractions, the maximum absorption wavelengths of fraction A and B were 266.1 and 257.4nm, respectively, and fraction C showed a weaker absorption peak at 274.8nm. Infrared (IR) spectrum results showed that all fractions (A, B, C) had both hydroxy and carboxylic groups, and fraction B and C had carboxylic ester group.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2003.04a
• /
• pp.142.1-142
• /
• 2003

저장 중 단감은 과피 및 과육의 변색 발생으로 인한 품질저하가 심각하게 발생하고 있는데, 아직까지 이를 방지하기 위한 원인 규명은 매우 미흡한 실정이다. 이에 본 연구에서는 단감의 재배지, 수확시기, 크기, 예조기간, 저장온도, 저장기간, 포장재의 두께 등을 달리하여 저장하면서 처리조건에 따른 단감 과육의 갈변 발생 관련성을 조사하였다. 단감의 변색발생 증상은 저장 1개월 이후부터 일부 나타나기 시작하여 저장기간이 경과할수록 심하였다. 단감의 갈변 발생률 및 갈변 정도를 실험 처리구별로 살펴보면 과수원, 수확시기, 예조기간, 저장온도, 포장재의 두께, 포장 내 가스조성에 따라 차이를 보였는데 단감의 수확시기가 늦을수록, 수확후 예조기간이 짧을수록, 저장을 위해 사용한 포장필름의 두께가 얇을수록 갈변발생정도가 심하였다. 또한 단감의 과수원에 따라서도 갈변의 발생률이 차이를 보여 동일지역이더라도 재배조건에 의하여서도 영향을 받는 것으로 나타났다. 이와 같은 결과를 종합하여 보면 단감 과육의 갈변발생은 수확 전 및 수확 후 인자들의 단독적인 영향이기보다는 복합적인 영향에 의한 것으로 추정되었다.