This study was done in order to investigate the bioconversion of ginsenoside, as well as the quality characteristics of fermented ginseng, by using lactic acid bacteria. Quality characteristics such as the thin layer chromatography(TLC) pattern, ginsenosides, total phenolic content, electron donating ability, and total sugar of fermenting ginseng and red ginseng were analyzed. The ginsenoside Rg2r, Rh2s and Rh2r of the fermented ginseng and red ginseng for 65 hours at a temperature of 37℃ were not detected. The ginsenoside Rg1 and Re contents have decreased, while the Rh1, Rg2s, Rd, Rg3r, and Rg3s have increased due to fermentation. The ginsenoside Rg3 of the fermented red ginseng has increased and the contents were 114.83∼131.68 μg/mL (control 104.56 μg/mL). The total phenolic content and electron donating ability of the red ginseng have totally decreased after 7 days of fermentation. The total phenolic contents of the fermented ginseng and red ginseng with different lactic acid bacteria did not show any tendency as different strains. The electron donating ability of the fermented ginseng has increased; however, the electron donating ability of the red ginseng has decreased. The total sugars of the fermented ginseng and red ginseng with different lactic acid bacteria have also decreased.

The physicochemical quality characteristics of the domestic and imported commercial dried persimmons were investigated. The moisture content of dried persimmon was approximately 22.78~61.64%, while the moisture contents of the Chinese dried persimmon were 22.78 and 28.20%, respectively, and were lower than the domestic dried persimmon The sulfur dioxide content of the 9 kinds of commercial dried persimmon was lower than 10 mg/kg, but not detected.

This study was conducted to investigate the change in quality attributes of fresh-cut potatoes with heat and browning inhibitor treatment (CW: dip in the cold water for 30 sec at 4℃, HW: dip in the water for 60 sec at 55℃, AA: dip in the 0.1% solution of ascorbic acid for 60 sec at 4℃, HA: dip in the 0.1% solution of ascorbic acid for 60 sec at 55℃) during storage at 5℃. During storage, fresh-cut potatoes treated with HA showed the lowest value in surface color. PPO and PAL activities of fresh-cut potatoes treated with HA were gradually increased during storage. Hardness, weight loss, soluble solids content and moisture content had no significant difference between the treatments. In sensory acceptance, fresh-cut potatoes treated for HA marked the best quality. Conclusively, heat and browning inhibitor treatment showed the positive effect on browning inhibition while maintaining the quality of fresh-cut potatoes.

No abstract

This study was conducted to determine the acetic-acid fermentation properties of apple juice (initial alcohol content, apple juice concentration, acetic-acid content, and inoculum size) in flask scale. At the acetic-acid fermentation of apple juice with 3, 5, 7, and 9% initial alcohol content, the maximum acidity after 10-day fermentation was 5.88% when the initial alcohol content was 5%. The acetic-acid fermentation did not proceed normally when the initial alcohol content was 9%. When the initial Brix was 1°, the acidity gradually increased, and the acidity after 12-day acetic-acid fermentation was 4.48%. Above 4% acidity was attained faster when the apple juice concentration was 5 and 10 ˚Brix than when it was 1 and 14 ˚Brix. When the initial acidity was 1% or above (0.3, 0.5, 1.0, and 2.0%), the acetic-acid fermentation proceeded normally. The acetic-acid fermentation also proceeded normally when the inoculum sizes were 10 and 15%, and the acidity after eight-day acetic-acid fermentation was 5.60 and 6.05%, respectively. Therefore, the following were considered the optimal acetic-acid fermentation conditions for apple cider vinegar: 5% initial alcohol content, 5 ˚Brix or above apple juice concentration, 1.0% or above initial acidity, and 10% or above inoculum size. Apple cider vinegar with above 5% acidity can be produced within 48 h under the following acetic-acid fermentation conditions: 7% initial alcohol content, about 1% initial acidity, and 10% inoculum volume at 30℃, 30 rpm, and 1.0 vvm, using 14 ˚Brix apple juice in a mini-jar fermentor as a pre-step for industrial-scale adaptation.