• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.683-688
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• 2007

Total polyphenolic compounds, DPPH radical scavenging activity, superoxide dismutase (SOD), vitamin A, C, E, flavonoid and anthocyanin of Rubus coreanus Miquel during maturation were investigated to expand the utilization of Rubus coreanus Miquel as functional food material. Physiological activities of unripened, middle-ripened and ripened fruit of Rubus coreanus Miquel were examined. The ripened fruit included higher contents of total polyphenolic compound compared with those of the other sample groups, unripened and middle-ripened fruit. SOD of unripened, middle-ripened and ripened fruit were 59.15, 80.05 and 95.03%, respectively. Scavenging concentration ($SC_{50}$) of unripened and middle-ripened fruit for 0.4 mM DPPH (1,1-diphenyl 2-picryl hydrazyl) was 2.3 mg/mL by weight, but only 1.6 mg/mL for ripened fruit. The vitamin A content of the Rubus coreanus Miquel was found to be lower as the fruit ripened; however, vitamin E showed the reverse pattern. In addition Rubus coreanus Miquel is a fruit which has a high vitamin C content regardless of maturity. The flavonoid contents of Rubus coreanus Miquel were in order of ripened fruit ($49{\mu}m/mg$)>middle-ripened fruit ($16.4{\mu}m/mg)$>unripened fruit ($15.4{\mu}m/mg$). Also, the contents of anthocyanin in ripened fruit were $394.50{\mu}m/mg$, which were higher than those of middle-ripened ($12.43{\mu}m/mg)$ and unripened fruit ($7.89{\mu}m/mg$).

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.225-231
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• 2005

This study was carried out to observe the stability of riboflavin in dietary supplements. Dietary supplements were in the type of tablet, powder, capsule and liquid. Various factors on the stability of riboflavin such as effect of light, storage temperature and time were examined using HPLC method. Samples were exposed to various temperatures (-9, 4, $30^{\circ}C$) and light at room temperature far 9 months. As well as storage period became longer, reduction rate constant of riboflavin increased. Riboflavin reduction rate constants were higher during storage with light than without light. And there was a significant difference of reduction rate constants in types of dietary supplement. In other words, riboflavin in tablet types was significantly more stable than the others, and liquid type was the most unstable. Therefore, type, light, and packing container of dietary supplements containing riboflavin would be considered in order to establish their appropriate shelf lives. In consideration with riboflavin decrease in dietary supplements, riboflavin would be appropriate for the nutritional labelling guide when predicting them at the end of shelf lives.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.442-447
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• 2009

Extracts from various parts of oriental melon were obtained and antioxidant property and antioxidant constituents including total phenol, total flavonoid, total vitamin C were examined. Free radical scavenging activity was measured by DPPH and ABTS method. Peel part of oriental melon showed the most potent scavenging activities against DPPH and ABTS radicals. The contents of total phenol, total flavonoid in peel were higher than other parts except vitamin C. The amount of vitamin C was the highest in placenta. The relationship between antioxidant activities and antioxidant constituents was determined and showed higher correlation coefficients between antioxidant activities and content of total phenol than other constituents. The above results suggest that phenolic compounds affect antioxidant activity of oriental melon and oriental melon has a good promise as functional food for enhancing health.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.540-544
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• 2012

The aim of this study was to evaluate the antioxidant activity, total phenolics, flavonoids, and vitamin C contents in peels of 11 commercial fruits commonly consumed in the Republic of Korea. The antioxidant activities were evaluated by ABTS, DPPH radical scavenging methods and reducing power. The peels of plum (Prunus spp.) and golden kiwifruit (Actinidia chinensis) exhibited the highest values of antioxidant activity and total phenolics, while the highest level of ascorbic acid was recorded in the peel of citrus fruit (p<0.05). There were positive correlations between the antioxidant activity assessed by both reducing power and ABTS methods and total polyphenol content ($R^2$=0.6356), suggesting that phenolic compounds are the major contributors to these activities. The results indicate that plum and golden kiwifruit peels can be used as natural antioxidant ingredients and in production of functional foods in the Korean diet.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.114-120
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• 2022

In this study, a comparative dissolution experiment was conducted between an immediate-release and a controlled-release vitamin C tablet applied with a technology to control the dissolution of vitamin C to maintain the vitamin C level in the human body. In order to confirm the dissolution rate (%) of vitamin C tablets, HPLC determination was conducted based on the dissolution test methods in the 'Korean Pharmacopoeia (No. 2020-88),' 'Guidelines on Specifications of Dissolution Tests for Oral dosage Forms,' and 'Standard and Specifications for Health Functional Foods (No. 2020-63)' from Ministry of Food and Drug Safety (MFDS). In addition, the dissolution pattern between the immediate-release tablet and the controlled-release tablet was comparatively analyzed. The analysis result confirmed that the immediate-release vitamin C tablet was 100% dissolved after 45 minutes, while the controlled-release vitamin C tablet was 100% dissolved after 480 minutes (8 hours). Furthermore, the dissolution rate (%) at 60 minutes was slower than that of the immediate-release vitamin C tablet. Based on these results, this study confirmed that the dissolution rate (%) test and development of controlled-release tablets containing vitamin C as the main component a re possible.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.955-961
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• 2014

This study was carried out to investigate the amounts of vitamin C in 22 sweet potato cultivars cultivated in Korea as well as evaluate the effects of cooking methods on vitamin C contents. Methods for determining vitamin C was validated by determining linearity, specificity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy using HPLC. Results showed high linearity in the calibration curve with a coefficient of correlation ($R^2$) of 0.9999. The LOD and LOQ values for ascorbic acid (AA) were 0.03 and $0.10{\mu}g/mL$, respectively. The relative standard deviations (RSDs) for intra- and inter-day precision of AA were less than 5%. The recovery rates of AA and dehydroascorbic acid (DHA) were in the range from 98.21~98.64 and 98.28~100.68%, respectively. Depending on cultivar, contents of AA, DHA, and total ascorbic acid (TA) in sweet potatoes varied in the range from 37.76 (Sinyulmi)~89.25 (Juhwangmin), 23.37 (Sinjami)~63.94 (Sinyulmi), and 68.52 (Sinjami)~115.95 (Juhwangmin) mg/100 g, respectively, and their average levels were $56.98{\pm}12.53$, $36.46{\pm}9.03$, and $93.44{\pm}12.00mg/100g$, respectively. The average TA levels were also dependent on flesh color, whish was significantly higher in general sweet potato and orange sweet potato than in purple sweet potato. Steaming, baking, and frying processes significantly reduced AA (10.61~58.41%), DHA (2.57~52.81%), and TA (14.54~49.92%) contents in sweet potatoes. The highest reduction of AA, DHA, and TA contents was observed after baking, followed by steaming and frying. We expect that the basic information provided by this study will be useful to plant breeders and food scientists.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.420-425
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• 2007

This study was conducted to find out the effect of vitamin C treatments on the storability of several baby vegetables; endive, green romaine lettuce, pak-choi, red romaine, lollo rosa, and ssamchoo. The vitamin C was treated by the foliar spray which was carried out 3 times before harvest or dipping in vitamin C solution for 5 minutes after harvest. The vitamin C contents of 6 different baby vegetables were higher in vitamin C treatments than control, whereas the difference of vitamin C content between treatments was disappeared after storage. The fresh weight of ssamchoo and lollo rosa lettuce treated by vitamin C was maintained higher than that of control. There was not significant difference in visual quality among treatments, though some of baby vegetables treated by washing with vitamin C showed better visual quality than the others. The contents of carbon dioxide, oxygen and ethylene in MAP with baby vegetables did not show any difference among treatments. As the result, high concentrated vitamin C treatment, such as the foliar spray and washing (dipping) had a role of increasing functionality, but the enhanced functionality, high vitamin C, did not affect storability in baby vegetables.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.899-906
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• 1996

The physicochemical and microbiological studies were conducted to examine the effect of pineneedle(Pinu densinora Seib. et Zucc) sap on the Kimchi fermentation. Kimchi with the addition of various levels(0, 0.5, 1.0, or 1.5%) of pine needle sap was fermented either at $4^{\circ}C$ for 15 days after placing at room temperature for 24 hours(Group A) or at $15^{\circ}C$ for 15 days(Group B). pH reached the optimal value of Kimchi fermentation(pH 4.2) on day 3 and day 4~7 in 0% treatment and pine needle sap treatments, respectively, which indicated that shelf-life of Kimchi was extended by 1~4 days by the addition of pine needle sap. Total acidity was decreased by the addition of pine needle sap. More rapid decrease in pH and increase in total acidity were observed in Group B than in Group A. Reducing sugar content was reduced to approximately 80% by day 4~5 in all treatments. Total vitamin C content was reached peak on day 1 of fermentation and then decreased in all treatments. Reducing sugar and total vitamin C contents were slightly increased by the addition of pine needle sap due to the components present in pine needle sap. Total viable cell number rapidly increased to reach Peak on day 3 and then slowly decreased during the fermentation. However, total viable cell number as well as reducing sugar and total vitamin C contents did not differ between Group A and Group B. In Group A, Lactobacillus cell number in 0% treatment continued to increase to reach peak on day 9, while the numbers in pine needle sap treatments reached Peak on day 5~9 and then gradually decreased throughout the fermentation. Unlike in Group A, Lactobaillus cell numbers in pine needle sap treatments in Group B continued to increase to reach Peak on day 7. As pine needle sap levels increased, total viable cell number and Lactobacillus cell number decreased regardless of fermentation temperatures. The results of this study indicate that pine needle sap causes to delay the Kimchi fermentation by slowing down pH drop and inhibiting the Lactobacillus cell growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1150-1154
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• 2002

This study was carried out to evaluate the nutritional value of soybean sprouts cultured in water with germanium. In the germanium treated soybean sprouts (GSP), the contents of moisture and ash were higher than those of control group (germanium non-treated soybean sprouts), with 88.7~90.2% and 16~24%, respectively. The contents of dietary fiber, vitamin C and total phenol of GSP were also higher than those of control group especially with more than 20~40% in total phenol being contained. Minerals of soybean sprouts were considerably increased during S-day cultivation. Of minerals, the contents of calcium and iron in GSP were higher than in the control. In particular there was no germanium in control group, but on the other hand, GSP had germanium of 159 ppm. Therefore, it may be suggested that, soybean sprout with germanium is better than soybean sprout without germanium in terms of nutrition.

• Food Science of Animal Resources
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• v.22 no.2
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• pp.172-178
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• 2002

Vitamins are bio-active materials and essential elements in our body but some of them are very low in milt Various vitamin-fortified milks are developed by the help of milk processing technology. However, heat treatments can affect vitamins contents in milk. Total loss of vitamins during the UBT(ultra high temperature) treatment was investigated. UHT treatment caused 60∼70% loss for vitamin C, and 30∼40% loss for vit. D3 and vit. E which are well-known as heat stable materials. On the contrary, degradation of water-soluble vitamins is relatively very low in the capsule-coated state. The capsule could reduce the loss of vitamins by protecting vitamins from the degradation factors such as heat, oxygen, lights etc. The fortification method using capsule can be thought as a new way to reduce the loss of vitamins during milk processing. Further study about heat treatment time and temperature, and capsule coating and materials will be required to minimize the loss of vitamins in milt.