• The Korean Journal of Food And Nutrition
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• v.24 no.1
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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 $-20^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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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.

• Korean Journal of Medicinal Crop Science
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• v.6 no.1
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• pp.33-37
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• 1998

Browning index rised rapidly within 15 hrs to 83% of total browning in Jang - ma (Dioscorea batatas Decne) tissues at $40^{\circ}C$ while 37% in Dan - ma. Therefore, the degree of browning process of Jang - ma was faster than that of Dan - ma. Browning in Jang - ma was inhibited by treatments of NaCl which showed 48 and 39% inhibition, respectively, after 48 hrs of incubation. Also the treatment of $80^{\circ}C$ heating showed excellent inhibition within 24 hrs. In the case of Dan - ma, browning process was inhibited by treatments of 1 and 0.5M NaCl and $70^{\circ}C$ heating, which showed 43, 26 and 23% inhibition, respectively, after 48 hrs of incubation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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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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• v.18 no.3
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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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• v.21 no.2
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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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• v.23 no.3
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• pp.271-275
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• 2008

Omija (Schizandra chinensis Baillon) has five lignans such as schizandrin, gomisin A, gomisin N, gomisin C and schizandrin C. Its major constituent, schizandrin, has a deterrent effect on nephrotoxicity of cisplatin, blood sugar and an ulcer of the stomach. In this study, we have investigated optimized extraction condition to make high functional beverage by quantifying schizandrin and measuring of browning index. Browning index was used as an index of color deterioration of anthocyanin. Browning index was decreased according to increment in extraction temperature and ethanol concentration. The optimum extraction time, extraction temperature and alcohol concentration levels were 3 hrs, $46^{\circ}C$ and 24% alcohol for high schizandrin concentration and desired browing index.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.287-294
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• 1983

Change of color, browning index, soluble protein, reducing sugar content, and available lysine were monitored for raw and extruded barely powders during four months of ambient and accelerated storage temperatures with $A_w$ of 0.31 and 0.71, respectively. Loss of whiteness and soluble browning pigments increased with increased $A_w$ and temperature. The raw sample had an increased rate of browning intensity than the extruded samples. Among the extruded samples, the added sucrose sample had the lowest rate of browning during storage. Loss of reducing sugar content in all samples increased with increased $A_w$ and temperature. The loss of soluble protein and of the available lysine also increased with increased $A_w$ and temperature. The loss of reducing sugar and of the available lysine was at least partly due to the Maillard browning reaction. These results have important implications in teh processing and storage of raw and extruded burleys.

• Food Science and Preservation
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• v.19 no.1
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• pp.31-36
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• 2012

Fresh-cut burdock roots were processed at 4 and $25^{\circ}C$, respectively. The fresh-cut burdock roots were treated with different browning inhibitors (3% citric acid, 3% sodium chloride, 0.3% cystein, and 3% sodium acetate solutions), and the changes in their quality and browning characteristics were investigated. The respiration rate and browning index of the cut roots prepared at $4^{\circ}C$ were lower than those of the cut roots prepared at $25^{\circ}C$. The soluble solid content was higher in the cut roots prepared at $4^{\circ}C$ than in those prepared at $25^{\circ}C$. The weight loss and flesh firmness were not affected by the processing temperatures. Among the browning inhibitors, 0.3% cystein showed the best browning-retarding effect. There was no difference in phenolic compound content between the browning-inhibitor-treated roots and the nontreated roots, but the PPO activity was higher in the latter than in the former. Therefore, the processing temperatures of fresh-cut burdock roots affected their quality and browning development, and the combination of a low processing temperature and the use of the proper browning inhibitor should be applied for the higher quality of the produce.

• Preventive Nutrition and Food Science
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• v.13 no.4
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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.