냉동조건이 건시의 저장 중 품질특성에 미치는 영향

Abstract

To evaluate the effect of freezing temperature on quality characteristics of dried persimmons, dried persimmons were frozen at -50°C (quick frozen, QF) and -20°C (slow frozen, SF) for 24 hr. Frozen persimmons were then stored at -20, -10, 0 and 10°C for 80 days. Total free sugar content of SF persimmons was higher than those of QF in the +10°C and -20°C stored samples. Except for samples stored at 10°C, the CIE L* values for QF persimmons were higher than those for SF persimmons. For samples stored at 10°C and 0°C, the CIE a* and b* values of SF samples were higher than those for QF samples. The texture of frozen dried persimmons was investigated to determine springiness, chewiness and hardness. Chewiness and hardness of samples held at 0°C were higher in SF than in QF persimmons. However, when stored at -10°C, chewiness and hardness were higher in QF than in SF samples. Springiness results were similar among the QF and SF persimmons held at different storage temperatures. For all storage temperatures, QF persimmons had a high soluble tannin content. All of the sample, the average soluble tannin contents of QF is 236.09 mg%. On the other hands, those of SF is 226.87 mg%. The results indicate that freezing rate and holding temperatures have significant effects on dried persimmon texture, soluble tannin level, and free sugar content. Further studies that include sensory evaluations are needed to determine the optimum freezing rate and holding temperature for dried persimmons.