The purpose of this study was to prevent excessive softening of seasoned spinach by heating and freezing through the pre-heating treatment in calcium chloride solution. The pre-heating temperature was set at 60℃, which supports the highest activity of pectinesterase around 60℃. Pre-heating spinach in calcium solution does not affect the chromaticity characteristics of spinach leaves and significantly improves its texture compared to conventional blanching only and pre-heating in water. The improvement of the firmness is related to the formation of strongly cross-linkages between carboxyl groups and Ca2+ by the action of the pectinesterase in spinach. For reheated spinach, the firmness of calcium chloride treated stems were 37.80~44.44 kg, and the control was 28.73 kg. The firmness of calcium chloride treated leaves was 19.73~40.79 kg, and the control was 9.63 kg. Additionally, the total aerobic bacteria in the fresh samples were 3.25~3.99 log CFU/g and 1.97~2.72 log CFU/g in the reheated samples. And the total coliform was not detected in the reheated samples. Considering the color, texture, microbial characteristics and taste quality, the optimum pre-treatment conditions to prevent excessive softening of spinach were 3% calcium chloride solution and 15minutes of treatment.

식품의 향기성분은 다른 주성분에 비해 미량으로 존재하지만, 풍미를 반영하는 중요한 지표로 색, 조직감과 더불어 식품의 품질을 평가하는 중요한 요소이다. 본 연구에는 SPME 추출방법을 이용하여 산고 품종 배주스의 휘발성 향기성분을 추출하여 GC-MS로 향기성분을 확인 및 동정하였다. 총 22종에 향기 화합물이 분리동정되었고, ester류 7종, aldehyde류 9종, ketone류 2종, alcohol류 1종, acid류 1종, furan류 1종 그리고 함황화합물 1종으로 구성되었다. 이 중에서 ethyl acetate, hexanal, ethyl hexanoate, ethyl 3-(methylthio)-2-propenoate, ethyl octanoate and 2-hexenal이 배주스의 주요 향기성분으로 간주되었다. 특히, ethyl acetate의 함량이 13.36~19.60 μg/kg으로 가장 높은 것으로 검출되어 전체 향기성분의 절반 이상을 차지하였다. 또한, 향기성분의 변화를 억제 및 추출능력 향상을 위해 분석용 시료에서 포화 염화칼슘 용액을 첨가하여 그 효과를 검증하였고, 착즙직후 바로 염용액으로 처리한 배주스에서 aldehyde류, acid류, furans류 및 s-compounds류은 유의적인 많은 것을 확인하였다. 본 연구결과는 배 원물의 품질저하 혹은 가공으로 발생한 향기 변화를 보완하는데 기초자료로 활용이 가능하며, 배주스를 활용한 가공식품의 향 품질을 향상시켜 고부가가치 가공식품을 개발하여 배의 소비 촉진에 기여할 수 있는 것으로 기대된다.

This study was conducted to develop easily chewable Korean rice cake (Garaedduk) for the elderly while maintaining its original form and flavor. We developed two types of easy-to-chew Garaedduk products by adding starch-degrading enzyme or trehalose, respectively. Characteristics of Garaedduk products were investigated and comparative analysis was carried out between control and experimental groups. The water content of control and enzyme-added Garaedduk was 43.55% and 44.11%, respectively, which was significantly higher than trehalose-added Garaedduk (40.30%) as free water content was reduced by the formation of hydrogen bonds between trehalose and water molecules. Due to the browning of reducing sugar produced by the decomposition of rice starch, Hunter b-value of enzyme-added Garaedduk was significantly higher compared to others. Hardness, adhesiveness, gumminess, and chewiness of experimental groups were lower than the control group. Consumer test scores showed significant differences with respect to overall liking, chewiness, and swallowing between control and experimental groups. Elderly preferred experimental Garaedduks over control and the experimental groups were evaluated to be softer, easily chewable, and swallowable.

The objective of this study was to develop anti-browning agents for commercial ready-to-eat pear products, which are preferred not only to maintain the flavor, color and texture of pears, but also to increase consumers’ preference. The sliced ‘Shin-go (Niitaka)’ pears were immersed in 5% and 10% oxidized starch, 1% citric acid, and 5% and 10% oxidized starch with addition of 0.1% sucralose for 3 minutes, and then they were packaged in vacuum sealed bags at 1℃ for 9 days. In order to evaluate the quality of packaged sliced pears, the quality index was determined in terms of color, firmness, soluble solids, and sensory quality. With the passage of storage time, no specific variation in firmness and soluble solids was observed. However, the ΔE value of the sliced pears treated with 5% oxidized starch solution was significantly lower than that of the other pears. Also, the Hunter L and b values of the sliced pears treated with 5% oxidized starch solution remained nearly constant from the beginning of storage. This observation shows that 5% oxidized starch solution was effective in reducing surface browning of sliced pears. Moreover, sliced pears treated with oxidized starch solution with addition of 0.1% sucralose were given an overall liking score which was slightly higher than that given to the other pears because of the sweetness of sucralose. In conclusion, 5% oxidized starch solution with addition of 0.1% sucralose was effective in reducing browning of sliced pears and in improving the taste of sliced pears.

In Western countries, kimchi, the Korean traditional fermented cabbage, is considered to be a healthy. However, it is one of the main sources of the high sodium content of the Korean diet. In order to decrease the sodium content, we manufactured a low-sodium kimchi (LK, salinity 1.0%) and 4 additional low-sodium kimchi starters in which each of 4 lactic acid bacteria (Lb. sakei 1, Lb. sakei 2, Lb. palntarum and W. koreensis) were added. The LKL1 to LKL4 samples were prepared by adding 4 single LAB starters, each with an inoculum size of 106 CFU/g, when the cabbage was mixed with kimchi sauce. The kimchi starters were fermented at 10℃ until reaching 0.5% acidity, and then stored at －1.5℃ until reaching 0.75% acidity. The pH and acidity of the starter kimchi changed more rapidly in the early phase of fermentation (up to 0.75% acidity) than control low-sodium kimchi. After the acidity of the kimchi starters reached 0.75% it remained constant. As the fermentation progressed, the total aerobic and lactic acid bacteria concentrations in the kimchi starter with added Lb. sakei 1 were the same as in the control low-sodium kimchi. The low-sodium kimchi fermentation of the kimchi starter with added Lb. palntarum progressed differently due to a difference in acid resistance. The kimchi starter with added Lb. sakei 2 had an overall liking score that was slightly higher than that of the control low-sodium kimchi due to a lower off-flavor