본 연구에서는 M16 A계통 '부지화'를 강세대목인 대목 '스윙글 시트루멜로' 또는 보통대목인 '탱자'에 접목하여 무가온 하우스에서 재배한 잎과 과실 사양의 수분상태 변화 및 과실 성숙기의 과실 가용성 고형물과 산 함량변화를 조사했다. 강세대목인 '스윙글 시트 루멜로'와 보통대목인 '탱자'에 접목한 M16 A계통 '부지화'의 대목에 따라 과실의 품질은 영향을 받는 것으로 나타났는데, '스윙글 시트루멜로' 대목은 '탱자' 대목보다 과실 가용성 고형물과 산함량이 낮았다. 동트기 직전에 측정된 과실사양의 수분포텐셜 및 팽압은 '스윙글 시트루멜로' 대목이 '탱자' 대목보다 조금 높은 경향을 보였으나, 삼투 포텐셜의 값은 '탱자' 대목이 '스윙글 시트루멜로' 대목보다 낮았다. 과실사양과 같은 시간대에 측정된 엽수분포텐셜 값의 변화도 과실 사양의 삼투포텐셜 변화와 유사한 경향을 보여주었다. 이상의 결과로 보아, M16 A계통 '부지화'에 있어 두개의 대목에 따라 잎의 수분 상태와 과실사양의 삼투포텐셜 차이가 있었으며, 이러한 차이로 인하여 과실 가용성 고형물과 산 함량에 차이가 나타나는 것으로 판단되며, 대목에 따른 수분 상태와 과실 품질의 차이는 대목의 뿌리분포가 영향을 미쳤기 때문인 것으로 사료된다.

This study was carried out to determine the quality characteristics of Jeju mandarin orange jellies containing sugar (control) and sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol) to be consumed by the elderly. The gelling agents were carrageenan and gellan gum at the concentration of 0.27%, respectively. The average age of the subjects for the acceptance test was 78. The lightness (L), redness (a), and yellowness (b) values of the carrageenan gel were higher than those of the gellan gum gel using the same sugars. The L, a, and b values of the carrageenan gel made with sugar derivative sweeteners were higher than those of the respective gel made with sugar. Whereas there were almost no differences between the color values of the gellan gum gels made with sugar and sugar derivative sweeteners, respectively. The gelling and melting temperatures of the carrageenan gel with erythritol were highest and those of the respective gel with xylitol were lowest among the sugar derivative sweeteners. The gelling and melting temperatures of the gellan gum gels with erythritol and isomaltooligosaccharide, respectively, were lower, and those of the respective gel made with xylitol were higher compared to that with sugar. There was no break down in the gellan gum gel. The break down rate of the carrageenan gel made with isomaltooligosaccharide was highest and that of the respective gel with xylitol was lowest among the sugar derivative sweeteners. The hardness, adhesiveness, springiness, and chewiness of the gellan gum gel were greater compared to the carrageenan gel. The adhesiveness levels of the carrageenan gels made with sugar derivative sweeteners were lower, and their springiness was higher than the respective gel with sugar. All the TPA characteristics of the gellan gum gels made with erythritol and xylitol, respectively, were higher than the respective gel with sugar. The rupture properties of the gels were the same as their TPA characteristics. The sensory acceptance of the carrageenan and gellan gum gels made with sugar were highest among all the sweeteners. There were no significant differences in the sensory acceptance scores of the carrageenan gels made with xylitol, erythritol, and sugar, respectively, and there were also no significant differences in the sensory acceptance scores of the gellan gum gels made with xylitol, sorbitol, and sugar, respectively. Xylitol was preferred in both the carrageenan and gellan gum gels. Thus, xylitol appears to be an appropriate alternative sweetener to sugar in Jeju mandarin orange jelly for consumption by the elderly, with regard to the acceptability and stability of the gel.

국내산 과일 주스 4종을 준비하고 식중독 유발균인 Listeria monocytogenes와 Salmonella Typhimurium를 접종하여 14일 동안 4℃에서 보관하며 항균 효과를 살펴본 결과 다음과 같은 결론을 얻었다. L. monocytogenes 에서는 매실 주스가 가장 뛰어난 효과를 나타내어 보존 14일만에 생존하고 있는 균을 전혀 측정할 수 없었으며, 그 다음으로 키위가 3.0 log만큼 억제를 보이는 항균 효과를 나타내었다. 감귤의 경우 1.0 log만큼 억제하는데 그쳤다. 매실주스 10%를 다른 주스에 혼합하였을 때 L. monocytogenes는 키위 즙에서 더욱 향상된 항균 효과를 나타내어 14일 후 생존 균을 측정할 수 없었고, 감귤주스에서도 1.5 log 만큼의 향상된 항균 효과를 나타내었다. S. Typhimurium은 전반적으로 L. monocytogenes 보다 더 쉽게 억제되는 경향을 보였다. 키위 즙과 매실 주스에서 접종한 모든 균이 보존 14일 후 생존하지 않는 것으로 관찰되었으며, 감귤의 경우에는 1.4 log 만큼밖에 억제하지 못했다. 10%의 매실과 혼합된 주스에 S. Typhimurium을 접종한 결과 키위 즙에서는 접종한 전 균이, 감귤주스에서는 3.2 log 만큼의 증가된 억제효과를 나타내었다. 이상과 같은 결과로 볼 때, 매실은 식중독 유발균에 대한 강한 항균 활성을 가지고 있으며 다른 과실주스에서의 식중독을 예방하기 위한 식품 보존 첨가제로서 사용이 가능할 것으로 기대된다.

This study was carried out to determine the quality characteristics of Jeju mandarin orange jelly with various gelling agent such as agar, k-carrageenan and gellan gum for the aged. The concentration of agar was 0.4-0.6% and that of k-carrageenan and gellan gum was 0.2-0.4%. The color value, gelling temperature, melting temperature, break down rate, textural properties and sensory acceptance test of Jeju mandarin orange jelly with various gelling agent were measured. Average age of the subjects for acceptance test was 78.23. Redness and yellowness of Jeju mandarin orange jelly with agar was lower than that with k-carrageenan. The gelling and melting temperature of Jeju mandarin orange jelly with agar was lowest among the jellies. Break down rate of Jeju mandarin orange jelly with agar was highest among the jellies. Above results showed that the stability of Jeju mandarin orange jelly with agar was inferior than that with k-carrageenan and gellan gum. Hardness, adhesiveness and springiness of Jeju mandarin orange jelly with agar was lowest among the jellies and sensory acceptance of Jeju mandarin orange jelly with gellan gum was highest among them. Thus, gellan gum was appropriate gelling agent for the Jeju mandarin orange jelly with regard to the acceptability and the depression of sour taste in Jeju mandarin orange jelly could improve the acceptability for the aged.