Kee-Jai Park

Effect of salinity stress on phenolic compounds and carotenoids in buckwheat (Fagopyrum esculentum M.) sprout

The effect of salinity stress on the nutritional quality of buckwheat sprouts cultivated for 1, 3, 5, and 7d was investigated by analysis of the antioxidant activity and levels of phenolic compounds and carotenoids. Treatment with various concentrations of NaCl (10, 50, 100, and 200mM) resulted in an increase in the amount of phenolic compounds and carotenoids in the sprouts compared with the control (0mM). The phenolic contents of sprouts treated with 10, 50, and 100mM after 7d of cultivation were 57%, 121%, and 153%, respectively, higher than that of the control (0mM NaCl). Moreover, the accumulation of phenolic compounds was primarily caused by an increase in the levels of 4 compounds: isoorientin, orientin, rutin, and vitexin. The carotenoid content of sprouts treated with 50 and 100mM NaCl was twice higher than that of the control. In addition, the antioxidant activity of ethanol extracts of the sprouts was increased by NaCl treatment. Although the growth rate of sprouts decreased with >50mM NaCl, these results suggest that treatment of an appropriate concentration of NaCl improves the nutritional quality of sprouts, including the level of phenolic compounds, carotenoids, and antioxidant activity.

Quality Characteristics of Kimchi Fermented with Abalone or Sea Tangle Extracts

This study evaluated the quality characteristics of fermented abalone-kimchi or sea tangle-kimchi during 28 days of storage at . Abalone and sea tangle were added as extracts compared to a control. We analyzed lactic acid bacteria, pH, acidity, salinity, reducing sugars, free sugars, organic acids, free amino acids, and sensory characteristics. The lactic acid bacteria levels were 4.4~5.3 log CFU/g on day 0, 6.8~7.1 log CFU/g after 7 days, and continued to rise during the fermentation period. The salinity increased slightly over time. As fermentation progressed, pH and reducing sugars, free sugars, and organic acid contents decreased. Free sugars, in particular, dramatically decreased about 70% compared to the initial day. The total free amino acid content was higher in abalone-kimchi. In terms of free amino acid contents, taurine was high in abalone-kimchi, while glutamic acid and aspartic acid content was high in sea tangle-kimchi. The sensory evaluation results show that abalone-kimchi and sea tangle-kimchi had higher scores for their savory taste and overall acceptance compared to the control.

Pulsed Electric Fields Effects on Drying of White Ginseng and Extraction of Soluble Components

This study was designed to investigate the effect of pulsed electric fields on the drying of ginseng and extraction of dried ginseng to reduce energy-consumption. Fresh ginseng was treated in a PEF system of 1 and 2 kV/cm electric field strength, 25 and 200 Hz of frequency, 30 μs of pulse width and pulse number of 175. The samples were subsequently dried for 26 h at 55±1℃, and the characteristic of hot-water extraction on dried ginseng was investigated. The ginseng pretreated with an intensity of 2 kV/cm (200 Hz, n=175) resulted in a reduction of approximately 38% for drying time. The influence of PEF treatment on the water extraction of dried ginseng at 95±1℃ was also investigated. The application of an electric field intensity of 2 kV/cm (25 and 200 Hz, n=175) increased soluble solid content, significantly reducing sugar content and free sugar content of the extract compared to non-PEF-treated samples.This study was designed to investigate the effect of pulsed electric fields on the drying of ginseng and extraction of dried ginseng to reduce energy-consumption. Fresh ginseng was treated in a PEF system of 1 and 2 kV/cm electric field strength, 25 and 200 Hz of frequency, of pulse width and pulse number of 175. The samples were subsequently dried for 26 h at , and the characteristic of hot-water extraction on dried ginseng was investigated. The ginseng pretreated with an intensity of 2 kV/cm (200 Hz, n

Removal Effects of Microorganism and Pesticide Residues on Chinese Cabbages by Electrolyzed Water Washing

This study investigated the washing efficiency of electrolyzed water for the removal of microorganisms and pesticide residues from Chinese cabbage. Initial total bacteria and coliform counts were 6.64 and 3.56 log cfu/g respectively. After washing, total bacteria count of tap water (TW) were 5.97 log cfu/g and low alkaline electrolyzed water (LAlEW) and strong acidic electrolyzed water (SAcEW) were 1.63-4.67 log cfu/g. Especially SAcEW-100 was found to the most effective method of washing the cabbages. After washing, the coliform count was dramatically reduced. The removal rate of pesticide residues by NaClO treatment (36.93-50.13%) was greater than that of TW treatment (32.28-38.46%). The removal rate of LAlEW-100 and SAcEW-100 was 63.79 and 78.30% respectively, and was higher than those of TW and NaClO treatments. The vitamin C content of the Chinese cabbages after all treatments did not differ significantly. Consequentially, the electrolyzed water was found to be effective to remove bacteria and pesticide residues from Chinese cabbage without affecting quality.