• 한국식품영양학회지
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• 제24권1호
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• pp.71-78
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• 2011

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and for different times(0, 10, and 20 min at $90^{\circ}C$) for blanching over a 6 month period. Analyses were conducted for moisture content, total sugar content, browning index, polyphenol compounds, PPO activity, and SEM. Moisture content and PPO activity were increased by storage time. The increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. The Browning index was increased by storage time, and increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. Scanning electronic microscopy(SEM) studies were performed on peeled chestnuts. Results showed that the wrinkle structure of the cell wall was enhanced by storage time, and the level of enhancement was higher at $-10^{\circ}C$ than at $-20^{\circ}C$.

• 한국식품과학회지
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• 제48권1호
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• pp.15-19
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• 2016

Drying process was applied to increase the antioxidant activity of onion powder: freeze-drying or air-drying at 50, 70, and $90^{\circ}C$ and onion extracts were obtained from each powder using water or aqueous ethanol (50%) at $25^{\circ}C$ and $60^{\circ}C$. In the color analysis, the freeze-dried powders showed higher $L^*$ and lower $a^*$ and $b^*$ values than did the air-dried ones. The browning index of powders air-dried at $90^{\circ}C$ was significantly higher than that of freeze-dried powders or those air-dried at temperatures below $90^{\circ}C$. Phenolic content in the extracts was 4.02-23.12 mg gallic acid equivalent/g sample, and was the highest in the extract from the sample air-dried at $90^{\circ}C$, regardless of the extraction condition. The highest antioxidant activity, measured by 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid and 1,1-diphenyl-2-picrylhydrazyl methods, was found in the powder air-dried at $90^{\circ}C$, which induced browning. These findings indicate that antioxidant activity depends more on browning during drying than on extraction conditions.

• 한국약용작물학회지
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• 제6권1호
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• pp.33-37
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• 1998

마의 껍질을 제거하거나 상처가 생겼을 때 발생하는 갈변현상을 억제할 수 있는 방법을 개발코자 실험을 수행한 결과는 다음과 같다. 1. 마는 박피후 시간이 경과할수록 갈변지수가 높아지는 경향를 보여 박피 후 15시간에 갈변지수가 장마는 38까지 증가한 반면 단마는 13이 었으며 이로서 장마가 단마보다 갈변이 빠르게 진행됨을 알 수 있었다. 2. 장마의 경우 NaCl 2M 처리시 갈변억제율이 48시간에 48%로 가장 높았고 특히 $80^{\circ}C$ 온탕처리의 경우 24시간까지 높은 억제율을 보였으나 이후 급격히 감소하는 경향을 보였다. 3. NaCl 1M 처리시 단마의 갈변은 43% 정도 억제 되었으나 NaCl 0.5M과 $70^{\circ}C$ 온탕처리는 비슷한 억제현상을 보였다. 그러나 $60^{\circ}C$ 온탕처리는 무처리보다 더 높은 갈변지수를 나타내었다.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1135-1139
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• 1997

Major factors inhibiting nonenzymatic browning in stored ginger paste were investigated using aqueous model systems with temperature, water activity, pH and sulfur compounds. Browning index and total gingerols were measured during storage. The rate of nonenzymatic browning reactions showed a strong depencence on temperature and pH and a negligible influence on water activity. It was also reduced by the addition of 0.04% N-actyl-L-cysteine(NAcCys), effectively. Activation energies for aqueous ginger model systems with and without 0.04% NAcCys were 29.0 and 25.8kcal/mole, respectively.

• Food Science and Biotechnology
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• 제18권3호
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• pp.636-640
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• 2009

The effect of post-cut vanillin treatment at high concentrations on changes of quality and microorganism in fresh-cut apples was studied. Apples (Malus domestica Borkh. cv. Fuji) were sliced, treated by dipping in different vanillin solution, 0, 40, 80, and 120 mM, packed in polyethylene bag, and then stored for up to 3 weeks at $4^{\circ}C$. Changes in total aerobic bacteria, yeast and molds, browning, soluble solids, and titratable acidity during storage were investigated. Growth of total aerobic bacteria throughout storage was strongly inhibited by vanillin regardless of treatment concentrations. Growth of yeast and molds was inhibited by vanillin of all concentrations until 2 weeks of storage. Levels of browning index, soluble solids, and titratable acidity were not significant difference among the treatment conditions until 2 weeks of storage. However, when stored for 3 weeks, browning index increased more at 80 or 120 mM vanillin, while soluble solids and titratable acidity more be decreased by 120 mM vanillin as compared with other treatment conditions. These results show that the usage of vanillin in processing of fresh-cut apples had a limitation for maintaining quality.

• Preventive Nutrition and Food Science
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• 제21권2호
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• pp.160-164
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• 2016

Two onions (Sulfur-1 and Sulfur-4) cultivated with different sulfur applications were thermally processed to elucidate the effects of heat treatment on browning index and antioxidant activity. Sulfur-4 onion had higher sulfur content compared with the Sulfur-1 onion. After thermal processing, browning intensity was different between the two onions juices, with lower values observed for Sulfur-4 onion juice. This suggests that sulfur inhibits the Maillard browning reaction. The total reducing capacity of the juices increased at higher thermal processing temperatures; however, it was also lower in the Sulfur-4 onion juice. This suggests that the heat treatment of onions enhanced their antioxidant activity, but the effect was offset in the Sulfur-4 onion juice presumably due to higher sulfur content. This study indicates that sulfur, a core element for the functionality of onions, can decrease the antioxidant activity of thermally processed onions because of its potential as a Maillard reaction inhibitor.

• KSBB Journal
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• 제23권3호
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• pp.271-275
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• 2008

오미자를 이용한 고기능성 음료개발을 위하여 이번 연구에서는 추출조건별로 오미자의 기능성분 함량 및 anthocyanin 색소에 대한 최적 추출조건을 설정하였다. 분쇄하지 않은 오미자를 이용해서 추출한 경우, Bl값은 차이가 없었으나, schizandrin은 20% 수준에 그쳐 최종적으로 분쇄한 오미자를 시료로 설정하였다. 분쇄한 오미자는 $40^{\circ}C$, 75% ethanol로 추출했을 때 schizandrin 함량이 가장 높았으며, Bl 값은 온도와 ethanol 함량이 높아 질수록 감소하였다. 높은 기능성과 제품의 관능성을 고려할 때 schizandrin 함량과 Bl값을 최적으로 만족하는 조건은 분쇄 오미자를 $46^{\circ}C$에서 24% ethanol을 사용하여 3시간 추출했을 경우 높은 값을 얻을 수 있었다.

• 한국식품과학회지
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• 제15권3호
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• pp.287-294
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• 1983

3가지 다른 조건하에서 제조된 압출보리와 생보리를 0.31 및 0.71의 수분활성과 $25^{\circ}C$ 및 $40^{\circ}C$의 온도에서 각각 4개월 저장하면서 색도, 갈색화지수, 가용성 단백질, 환원당 및 유효성 리진의 변화에 대한 수분활성과 온도의 영향에 대하여 연구하였다. 저장기간의 경과와 함께 수분활성과 온도가 증가함에 따라 모든 시료에서 백색도의 손실이 증가하였다. 생보리는 압출보리보다 저장중 갈색화 지수의 증가가 심하였고, 설탕을 첨가하여 제조한 압출보리는 다른 압출보리보다 저장중 갈색화가 적었다. 수분활성과 온도가 증가함에 따라 모든 시료중의 환원당, 가용성 단백질 및 유효성 리진의 함량이 감소하였으며, 이와같은 결과는 저장중 Maillard반응에 의한 것임을 알았다.

• 한국식품저장유통학회지
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• 제19권1호
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• pp.31-36
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• 2012

신선절단 우엉의 제조에 있어 가공 온도와 갈변 억제제의 영향을 구명하기 위하여, $4^{\circ}C$와 $25^{\circ}C$에서 제조하거나, 각종 갈변 억제제(3% citric acid, 3% sodium chloride, 0.3% cystein, 3% sodium acetate 용액)에 침지 처리한 신선절단 제품의 품질 및 갈변 특성을 조사하였다. 가공온도 $4^{\circ}C$제품이 $25^{\circ}C$ 제품보다 호흡량과 갈변도는 낮았으며 가용성 고형분 함량은 높았다. 반면에 제품의 중량 감소율과 과육경도는 가공온도의 영향을 거의 보이지 않았다. 갈변 억제제의 종류에 따라 제품의 갈변도는 다르게 나타났으며 그 중 0.3% cystein 처리가 갈변을 가장 지연시키는 효과를 보였다. 제품의 페놀성 물질 함량은 갈변 억제제 처리 유무에 따른 큰 차이를 보이지 않았고, PPO 활성은 갈변 억제제 처리구보다 무처리구에서 비교적 높은 수준을 보였다. 이로써 가공 온도가 신선절단 우엉 제품의 갈변을 포함한 품질 특성에 영향을 미치는 것이 확인되었고, 고품질 제품을 위해서는 저온 가공에 적절한 갈변 억제제 처리가 병행되어야 할 것으로 여겨진다.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.306-312
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• 2008

This study investigated the influence of pH on the color development of melanoidins formed from amino acid enantiomer model systems. For this, the color development was evaluated by measuring browning at 420 nm and color measurements by spectrophotometry and colorimetry. The browning and browning index showed no difference according to the type of amino acid enantiomers, while that formed from the D-Asn system was the only difference according to pH level. The tristimulus value of melanoidins formed from all model systems was located on a dominant wavelength of 475 nm, the blue zone of the diagram. In addition, the $L^*$, $a^*$, $b^*$, $C^*_{ab}$ values, and ${\Delta}E^*$ index on the basis of the type of amino acid enantiomers, the differences were markedly found at pH 4.0. At pH 7.0, significantly differences were found in the $L^*$, $a^*$, $b^*$ values, and ${\Delta}E^*$ index and not in the case of the lysine enantiomers. In addition, at pH 10.0, the differences were found in the $a^*$ and $b^*$ values from the lysine enantiomers and $C^*_{ab}$ value from the asparagine enantiomers. Therefore, the color development of melanoidins was influenced by the type of amino acid enantiomers and pH levels. Especially, it is thought that the $a^*$ and $b^*$ values can be used to explain the differences among the amino acid enantiomers in the color development of melanoidins.