• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.152-157
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• 2000

In order to select the optimum drying method for the production of cinnamon extract, water extract and 70% ethanol extract of cinnamon were prepared. And then several drying method of oven drying, vacuum evaporation, spray drying and freeze drying were performed. Content of cinnamic acid, cinnamic aldehyde, eugenol, tannin and free sugar, and antioxidant activity, degree of browning, pH, color value, turbity and solubility were compared. In water extract, contents of cinnamic acid, cinnamic aldehyde, eugenol were 29.45mg/100g, 94.86mg/100g, 120.75mg/100g and decreased to 4.76%∼44.21%, 5.30%∼48.05%, 3.66%∼21.83% by oven dyring, vaccum drying, spray drying respectively, but freeze drying showed a little decrease of those components. In 70% ethanol extract, effectual components decreased to 76.05%∼88.38% and 26.86%∼78.76% by freeze drying and vacuum evaporation respectively. Antioxidant activity decreased by drying and decreasing rate in 70% ethanol extract was lower than water extract. Degree of browning increased as the drying temperature increased. Tannin and free sugars were little affected by drying temperature. Solubility decreased in oven drying and 70% ethanol extract. Overall data suggested that optimum drying methods of cinnamon extract were freeze drying in case of water extract and freeze drying and vaccum drying in case of 70% ethanol extract.

• Food Science and Preservation
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• v.20 no.6
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• pp.760-765
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• 2013

The image analysis as a tool for evaluation of browning degree on fresh-cut lotus root was studied. The fresh-cut lotus root treated as 4 groups (Cont-without any treatment, DB-blanching at $50^{\circ}C$ for 5 min in distilled water, AB-blanching at $45^{\circ}C$ for 5 min in 1% ascorbic acid, CB-blanching at $45^{\circ}C$ for 5 min in 1% citric acid). The samples treated with each methods were packaged with 0.04 mm polyethylene bag ($25cm{\times}30cm$) and stored at $4^{\circ}C$ for 9 days. On the RGB color space, the AB and CB group showed high R, G, B value. On the HSV and CIE $L^*a^*b^*$ color space, the AB and CB group showed low browning area, $a^*$, $b^*$ value and high $L^*$ value. Polyphenol oxidase activity was low in the AB and CB groups in all storage period. This result means that the AB and CB groups were inhibited the development of tissue browning. The result of sensory evaluation also supported this opinion. And the correlation coefficient between sensory evaluation with all color values was over 0.84. Especially, the $L^*$ value showed the highest correlation coefficient (0.93). In conclusion, the image analysis is suitable for analysis of browning degree on fresh-cut lotus root by analyzing diverse color value.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.384-388
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• 1996

This research was conducted to investigate the effective methods for browning inhibition on yam (Dioscorea aimadeimo) during dehydration by physical and chemical pretreatments. Moisture, crude protein, crude fiber and N-free extract contents of yam were 81.17%, 1.43%, 0.29% and 15.81%, respectively. Yams were sliced to 0.5 cm thickness and placed to single and poly layer in plastic tray, and then changes of their weights were measured during air dehydration at $50^{\circ}C,\;65^{\circ}C,\;and\;80^{\circ}C$. The dehydration time reaching to optimum moisture level for the pulverization of the yam slices were 10, 6, 3 hours(single layered) and 12, 7, 5 hours(multi layered) at the respective temperature. To inhibit browning at $80^{\circ}C$ air dehydration, water and steam blanching, microwave treatment effects were investigated on yam slices for 30 sec. and 60 sec. Steam blanching for 30 sec. was comparatively effective to inhibit browning of yam slices. Yam slices were immersed in single and combined browning inhibitor solutions and evaluated for browing degree during dehydration by the values of Hunter L, a, b and ${\Delta}E$. The most effective pretreatment to inhibit browning of yam slices was immersion In the solution containing 500 ppm of citric acid and 1000 ppm of cysteine for 1 min.

• Journal of the Korean Society of Food Culture
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• v.10 no.2
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• pp.97-100
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• 1995

Three potato cultivars were prepared as slices and stored for 4 weeks at $5^{\circ}C$. Changes in Vitamin C content and other quality factors, such as color, pH, soluble solid and protein content were determined. Vitamin C content and L value decreased in three potato cultivars. Initial Vitamin C contents of three potato cultivars varied from 49.27 mg% in Sumi to 56.40 mg% in Namjak. Changes in L value showed that the tendency of browning in Daejima was slower than Sumi and Namjak. Changes in pH were small. Soluble solids and protein content increased and varied by cultivar. From the correlation analysis, correlation between browning degree and Vitamin C content was low in three potato cultivars.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.12-18
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• 2001

This study was conducted to investigate the effect of tobacco curing on far infrared light on the quality of flue-cured tobacco leaves. Physicochemical characteristics such as alkaloid, total sugar, total nitrogen, starch, total phenolic compounds, browning degrees, and color differences, in cured tobacco leaves were compared between hot air and far infrared curing methods. There was no significant difference in sugar/nicotine ratio and nitrogen number between the curing methods, while the contents of ether extract and filling capacity were increase by far infrared curing. Therefore, it was expected that far infrared curing might be effective for high aroma and physical properties of the cured tobacco leaves.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.801-807
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• 1988

Antithiamine activity of raw and processed brackens (Pteridium aquilinum) was evaluated by means of the thiochrome fluorescence and Lactobacillus viridescens bioassay methods and inter-related with the phenolic content and degree of browning. As blanching time of bracken elapsed, its antithiamine activity was enhanced whereas the phenolic content and brewing declined. Increased salt concnetrations in boiling water also raised the antithiamine activity, phenolic content and browning of raw bracken. When dried bracken was treated with sodium bicarbonate solution or soaked in running water, its antithiamine activity greatly decreased along with the increased phenolic content and browning. Heat cooking of bracken brought about a slight decrease in the antithiamine activity, phenolic content and browning. It was concluded that antithiamine activity existing in raw bracken Is reduced by various treatments, particularly by soaking in running water and that phenolics in bracken may play an important role in thiamine decomposition.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1289-1294
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• 1999

To identify the effect of packaging film on browning reaction of dried squid, 3 kinds of packaging film$(NYLON\;12\;{\mu}m/LDPE\;80\;{\mu}m)$ including transparency, white, black film were tested about browning degree of dried squid during storage at ambient temperature for 50 days. During storage period, water content and water activity were maintained almost constant, and microbial count was not changed. When color index was measured by color difference meter, L value and ${\Delta}E$ value were the highest in the dried squid packaged with transparency film. ${\Delta}E$ value was rapidly increased in early packaging period(within 10 day). TBA value was showed same tendency with ${\Delta}E$ value in early storage period. So, the browning was supposed to originated from lipid oxidation by UV light transmitted through packaging film in the early storage period.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.382-386
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• 1997

In the present study, an attempt was made to investigate the effects of steeping treatment on browning of onion hydrolysate. After steeping treatment with solvents, phenols content of methanol and ethanol were showed 25.1mg/ml and 24.9mg/ml. And absorbance of methanol and ethanol was showed 0.26 and 0.22. L and b value of treatment with methanol and ethanol were lower than other solvents. Browning reaction of onion hydrolysate was decreased with increasing concentration of ethanol. Treatment of above 80% ethanol was effective to remove phenols and was showed a low color intensity. Treatment with 80% ethanol was more effective than addition of cystein to remove phenols and to decrease browing degree.

• Food Science and Preservation
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• v.22 no.1
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• pp.154-157
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• 2015

To maintain the freshness and to prevent browning of cut Kimchi cabbages, the effect of the cutting process using a ceramic knife under $N_2$ blowing on the quality of the cut Kimchi cabbages was investigated. Kimchi cabbages cut with a ceramic knife under $N_2$ gas blowing conditions (NC) were stored at $5^{\circ}C$ for 7 days, and their weight reduction ratio and the browning degree and appearance were compared with those of the control treatment samples (OS; cut with a stainless steel knife under normal air, OC; cut with a ceramic knife under normal air). The weight reduction ratios were 0.07~0.13%, and the NC treatment showed the lowest reduction ratio among all the treatments (p<0.05). The Hunter L values increased, but the a and b values decreased after 5-day storage in all the treatments. The NC treatment had higher L values but lower a and b values than the OS and OC treatments. The browning degrees by Hunter color value, PPO activity, and appearances were the least in the NC treatment (p<0.05). The cutting process with a ceramic knife under $N_2$ blowing could be applied to the cutting of vegetable products and for minimal fruit processing.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.622-626
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• 1991

Antioxygenic effects of browning reaction product(BRP) obtained from 2M L-ascorbic acid(AsA) solution by heating at $85^{\circ}C$ were investigated. BRP obtained from AsA solution(pH 2.30) without pH adjusting showed slightly antioxygenic effect. As heating time increased, powers of antioxygenic activity of BRP did not increase. Retained AsA after heating did not effect antioxygenic activity of AsA solution. After adjusting pH of AsA solution to 2.3, 4.0, 7.0, 9.0 and 11.5 respectively, BRP were obtained from these AsA solution by heating at $85^{\circ}C$ for 15 hrs. Among these BRPs, BRPs of pH 2.3 and 4.0 showed no antioxygenic effect, lower browning degree and higher retained AsA, but had stronger reducing power. While those of pH 7.0, 9.0 and 11.5 had stronger antioxygenic activity, higher browing degree and lower retained AsA, but showed weaker reducing power. After adjusting pH of AsA solution to 7.0, antioxygenic activities of BRP which was obtained from this AsA solution by heating respectively at $85^{\circ}C$ for 0, 3, 5, 10, 15 and 25 hrs increased in proportion to heating time.