• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.253-258
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• 1996

Stabilities of sweets potato f-amylase on various reagents were studied. The enzyme was stabilized by bovine serum albumin, Triton X-100 and 2-mercaptoethanol of 0.04%. Among them, bovine serum albumin was the most effective. And enzyme stability was increased by using the deairated solution. The enzyme activity was remained 0% in the absence of glycerol, 25% in the presence of 20% glycerol and 50% in the presence of 40% glycerol at 37$^{\circ}C$, for 15 hours in pH 11. SDS inhibited the enzyme, and 2-mercaptoethanol and dithiothreitol stabilized it.

• Journal of Nutrition and Health
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• v.18 no.1
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• pp.55-62
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• 1985

The storage stability of the developed Formula of infant foods was investigated. The results are summarized as follows : When formula A and B were stored at room temperature and refrigeration temperature, there was no remarkable changes in consistency. In frozen state, formula A showed more stability in consistency than formula B and formula A could be stored for 6 months without problems due to retrogradation of starch. The heat treatment of both A and B resulted in the increase of a-value, while L-and b-value showed no such change. But from the 4th month at room temperature, and 5th to 6th month at refrigeration appeared an increase in a -value, hence the browning reaction, while frozen samples did not show noticeable changes in surface color. The heat treatment also caused an increase in POV on both formula. The extent of changes in POV during storage varied with storage temperatures and samples.

• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.287-294
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• 2002

As a series of studies on improving quality of seasoned-dried Pacific saury, storage stability of seasoned-dried saury treated with liquid smoke (T2 product) was examined during storage at ambient temperature $(19\pm5^{\circ}C)$, comparing with control (C, seasoning only) and T1 (treatment of $0.05\%$ Rosemary as a antioxidant). The histamine contents (15.33-32.21mg/100g) of 3 seasoned-dried products were much lower than tolerance limit of intake during 80 days of storage. The water activity of 3 seasoned-dried products was in range of 0.692­0.735. The pH of T2 showed relatively lower than the others during storage. The POV of T2 was slightly higher until 30 days, but was lower after 45 days compared with Tl. The TBA value and viable cell count of T2 were the lowest among the samples during storage. The color values of 3 seasoned-dried products were not significantly different during storage. The sensory scores of T2 was the highest than those of T1 and C during storage. Therefore, liquid smoking method was a useful technique to extend shelf-life and retain good sensory quality of seasoned-dried Pacific saury.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.384-388
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• 1995

High content of polyunsaturated fatty acid in fish oil makes it very susceptible to oxidation, which prevent fish oil from successful application to food processing or functional foods. To resolve this problem, oxidation stability model of fish oil was developed using the following differential equation : $dp/dt=k{\cdot}p(t){\cdot}[P_{max}\;-\;p(t)]$. This differential equation can be intergrated using analytical techniques to give : $p(t)=P_{max}/[1\;+\;[(P_{max}/P_{(0)})\;-\;-1]{\cdot}EXP(-K_p{\cdot}t)]$. At 50, 60, 70 and $80^{\circ}C,\;K_p$ were 0.00535, 0.01345, 0.02516 and 0.04675, respectively. The proposed model was well agreed with the measured data except for some minor deviations. In addition, $K_p$ was expressed as a function of temperature : $K_p=(1/P_{max})EXP\;[1\;-\;(8148/T)+20.1]$. Where T is absolute temperature($^{o}K$).

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.1-6
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• 2004

Fresh ground beef was mixed with ascorbic acid, basil essential oil, majoram essential oil, or each essential oil combined with ascorbic acid and stored at 1 $\pm$ 1$^{\circ}C$ for 7 days. Color, lipid oxidation (TBARS formation), aerobic bacterial counts and pH were determined. Basil and majoram essential oils were effective in inhibiting color deterioration, lipid oxidation and bacterial growth. The combined addition of basil and ascorbic acid showed the highest protection against color fading, followed by majoram + ascorbic acid, and ascorbic acid alone. Basil and majoram essential oils were most effective in delaying TBARS formation (p < ().01). Ascorbic acid did not exert an antioxidative effect and even exhibited a pro-oxidant effect. The pH values of all samples increased slightly, but no significant differences were observed, either among treatments or throughout the storage time (p > 0.05).

• Animal Bioscience
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• v.34 no.4
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• pp.701-713
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• 2021

Objective: The present work was undertaken to evaluate the effects of storage time, choline chloride, and high concentrations of Cu and Zn on the kinetic behavior of vitamin degradation during storage in two vitamin premixes and four vitamin-trace mineral (VTM) premixes. Methods: Two vitamin premixes (with or without 160,000 mg/kg of choline) were stored at 25℃ and 60% humidity. Besides, four VTM premixes were used to evaluate the effects of choline (0 vs 40,000 mg/kg) and trace minerals (low CuSO4+ZnO vs high CuSO4+ZnO) on vitamin stability in VTM premixes stored in room, and the VTM premixes were stored in room temperature at 22℃. Subsamples from each vitamin and VTM premix were collected at 0, 1, 2, 3, 6, and 12 months. The retention of vitamin A (VA), vitamin D3 (VD3), vitamin E (VE), vitamin K3 (VK3), vitamin B1 (VB1), vitamin B2 (VB2), vitamin B3 (VB3), vitamin B5 (VB5), and vitamin B6 (VB6) in vitamin premixes and VTM premixes during storage was determined. The stability of vitamins in vitamin premixes and VTM premixes was determined and reported as the residual vitamin activity (% of initial) at each sampling point. Results: The effect of choline on VK3 retention was significant in vitamin premixes (p<0.05). The negative effect of storage time was significant for the retentions of VD3, VK3, VB1, VB2, VB5, and VB6 in vitamin premix (p<0.05). For VTM premixes, negative effect of storage time was significant (p<0.05) for the losses of vitamin in VTM premixes. Choline and high concentrations of Cu and Zn significantly increased VA, VK3, VB1, and VB2 loss during storage (p<0.05). The supplementation of high concentrations of Cu and Zn significantly decreased the concentrations of VD3 and VB6 (p<0.05) in VTM premixes at extended storage time. Conclusion: The maximum vitamin stability was detected in vitamin and VTM premixes containing no choline or excess Cu and Zn. The results indicated that extended storage time increased degradation of vitamin in vitamin or VTM premixes. These results may provide useful information for vitamin and VTM premixes to improve the knowledge of vitamin in terms of its stability.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.92-98
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• 2008

In this study, salad dressing was prepared with added soypaste and its quality characteristics were evaluated. In terms of nutrient composition, the soypaste dressing contained higher levels of protein, minerals, and vitamins, and fewer calories, as compared to commercial mayonnaise. In addition, sensory evaluations revealed that the soypaste dressing received higher scores for flavor, taste, viscosity, and over-all preference than the commercial mayonnaise. The viscosity and emulsion stability of the freshly made soypaste salad dressing were 2,400 cP and 80%, respectively. And during 8 weeks of storage at $5^{\circ}C$, the viscosity and emulsion stability values remained similar to those of freshly made dressing. With prolonged storage time, the Hunter's color b-value slightly increased, whereas the L- and a-values slightly decreased. In terms of antioxidant activity, DPPH radical scavenging activity and lipid peroxidation inhibition were 2- to 3-fold higher in the soypaste salad dressing as compared to the commercial mayonnaise. And the soypaste dressing's antioxidant activity increased according to the storage temperature and time. Total microbial numbers increased to 6.2 log CFU/mL in the soypaste dressing, but E. coli was not detected. Overall, the results suggest that soypaste salad dressing could be introduced as a commercial product.

• Journal of Nutrition and Health
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• v.29 no.10
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• pp.1080-1086
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• 1996

The purpose of this study was to determine the effects of taurine supplementation on the hepatic lipid peroxidation, activiteis of defense enzymes and membrane stability during rat hepatocarcinogenesis. Hepatocarcinogenesis was induced by Solt & Farber modification. Lipid peroxide contents of carcinogen treated group which was not supplemented with taurine were lower than those of control group. This might be that peroxide is decreased because of the activation of detoxifing enzyme. Glutathione S-transferase(GST) activites of carcinogen treated groups were significantly (p<0.05) increased compared to those of control groups. The GST activities of group supplemented with taurine before treatment of carcinogen and during the all period of experiment were only less increased. In carcinogen treated groups, glutathione peroxidase(GPx) activites of groups supplemented with taurine were higher than those of non supplemented group. By carcinogen treatemtn, glucose 6-phosphatase(G6Pase) activites, index of membrane stability were decreased, but in carcinogen treated groups supplemented with taurine, they were less decreased. These results suggest that taurine supplementation seems to inhibit lipid peroxidation, to change the activities of defense enzymes and to prevent to membrane disintegration during chemically induced hepatocarcinogenesis.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.241-245
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• 1997

In order to make natural food color from Gardenia, we investigated optimal conditions of color extraction, and thermal stability and light stability of color extracted compared with Yellow-4. In case of ethanol extraction, optimal conditions for color extraction were substrate 10%, 4$0^{\circ}C$, pH 7.0 and 42rs, respectively. In case of water extraction, optimal conditions for color extraction were substrate 10%, 7$0^{\circ}C$, pH 7.0 and 48hrs, respectively. Extraction yield in the optimal conditions was 75% in ethanol and 63% in water. The thermal stability and light stability of Yellow-4 were both upper 98%, but those of Gardenia yellow color were 62 and 90%, respectively.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.187-192
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• 2007

The objectives of this study were to examine changes in the color and antioxidant compounds of paprika powder under various conditions, as well as to establish the suitable conditions for drying and storage. Paprika was dried using the following methods: freeze-drying, vacuum drying, far infrared-ray drying, and hot-air drying. Measurements of the moisture content, color pigments, and antioxidant compounds (total carotenoids, capsanthin, ascorbic acid, and total polyphenols) were completed during 120 days of storage at 4 and $30^{\circ}C$. We found that drying methods, storage temperatures, and packaging materials affected the American Spice Trade Association (ASTA) and Hunter color values, as well as the antioxidant content of paprika powder. There was a high correlation (r=0.87, p<0.01) between the ASTA color and the $a^*/b^*$ value. The loss of red color was closely related to the reduction of moisture content (r=0.81, p<0.01) during storage. Drying paprika with a low temperature in the absence of air resulted in better retention of the carotenoids and ascorbic acid. Also, as the retention of the carotenoids and ascorbic acid increased, the stability of the red pigment increased. Freeze-drying was found to be the most suitable drying method for the stability of the antioxidant compounds and red pigment.