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The purpose of this study is to investigate the total polyphenol and antioxidant activities of radish buds (Raphanus sativus L.) based on sprouting periods and extraction solvents in order to present basic data that are needed for using the radish buds as functional food material. The antioxidant activities were assessed by using various antioxidant models (DPPH, TBARS, Rancimat method, POV). The total polyphenol contents according to the extraction solvents were 84.11 and 296.51 mg/g, and the ethanol extract on day 4 of showed the highest value as 296.51 mg/g. As for DPPH radical-scavenging activity, on the day 4 of sprouting, water extracts indicated the highest scavenging activity by 86.67%, and the acetone extracts indicated a rather low scavenging activity as 77.23%. As for TBARS measurement of the radish bud extracts on day 4 of sprouting the extract of 70% ethanol was highest (71.48%). On day 8 of sprouting the TBARS value was increased and the methanol extract was highest (78.99%). As for the oxidative induction period on day 4 of sprouting in Rancimat measurement, the methanol extract was highest (6.07 hours) on day 4 and the antioxidant index was 1.16. On day 12 of sprouting, the general oxidative induction period tended to be reduced to 5.25 to 5.91 hours. In the peroxide value measurement on day 4 of sprouting and beginning of the storage, the extracts showed no difference between 3.02 meq/kg oil and 4.12 meq/kg oil, and on the day 60 of storage, the water extract (43.83 meq/kg oil) and the methanol extract (45.42 meq/kg oil) were lowest with higher antioxidant effect. In conclusion, the radish bud extract with higher total polyphenol contents and antioxidant activities may serve as functional material for food additives, such as natural antioxidants and food preserving agents.

The purpose of this study was to investigate the effect of Gastrodia elata Blume concentrate on quality characteristics of Gastrodia elata Blume jelly. The Gastrodia elata Blume jelly samples were divided into five groups by adding different Gastrodia elata Blume concentrates.The five groups were divided into GBJ-0, GBJ-5, GBJ-10, GBJ-15, and GBJ-20 (Gastrodia elata Blume jelly with 0, 5, 10, 15, and 20% Gastrodia elata Blume concentrate). The highest contents of crude protein and crude ash, and the brix in the GBJ-20 sample were 0.34 and 0.59%, and 22.28°Brix, respectively. The crude fiber and pH change (4.65-4.76) were not significantly observed in any of the GBJ samples.Turbidity, degree of brownness, and total phenolics increased with an increasing the amount of extract. A significant difference was observed between samples with and without the extracts in terms of hardness, springiness, gumminess, and chewiness, as well as K, Mg, Cu, Mn, and Zn contents. Hardness, gumminess, and chewiness increased in all GBJ samples with an increase the amount of extract added, whereas adhesiveness decreased. The highest tartaric acid content in the GBJ-0 sample and malic acid in the GBJ-20 jelly sample were 15.58 mg/100 g and 137.45 mg/100 g, respectively. The levels of Ca, K, and Mg increased with an increase in the amount of added extract. The highest score for overall acceptance (4.13) was in the GBJ-10 sample with 10% Gastrodia elata Blume concentrate.

Vacuum drying was conducted for a steamed pumpkin-sweet potato slab to improve its quality, convenience and preference as snack. Steamed sweet potato was dried from 30 to 60 o C for 12 hr, after which moisture contents, colors, and taste were evaluated. The lowest moisture content was 0.22% upon vacuum drying at 60 o C for 12 hr. Lightness decreased while other color values (a, b and ΔE) increased with increasing drying temperature and drying time. Reducing sugar and soluble solid contents ranged from 98.7～268.11 mg/g and 19～72 o Brix, respectively. Sensory score of the sample was the highest when dried at 50 o C for 6 hr. The optimum drying conditions were predicted to be 48.5～62 o C and 5.1～7.1 hr by response surface methodology.

The objective of this study was to establish 'use by' dates for a marinated chicken thigh meal-kit by identifying the most suitable quality indicators using chemical, microbiological, and sensory evaluations. Marinated chicken thigh aged for 24 h in marinade sauce was vacuum packed and stored at 5°C, 0°C, or −20°C for up to 90 days. An investigation of changes in quality characteristics showed volatile basic nitrogen (VBN) following the zero-order reaction best correlated with quality factors (R 2 =0.9894). The VBN limit, as calculated by substituting the sensual limit criterion (5.00), obtained by regression analysis between VBN and overall acceptance by sensory evaluation, was 17.50 mg/100 g. Furthermore, based on the reaction rate constants at the three storage temperatures, storage periods at 5°C, 0°C, or −20°C were 4.23, 17.07, and 228.79 days, respectively. The storage period at −5°C, the preferred storage temperature in large food stores, was calculated using the Q10-value at 25.14 days. The 'use by' dates of the marinated chicken thigh meal-kit based on storage at 5°C, 0°C,