Effect of Temperature and Stirring speed on the Processing of Plum Concentrated Extract.

온도 및 교반속도가 매실엑기스 가공에 미치는 영향

Plum highlighted as a health food is needed to diversify the processed products because labor storage is big problem since the fruit was producted massively in June. The Plum was extracted by the pressing type extractor after washing, drying and removing the seed by seed separator. The crude extract was concentrated with stainless steel vessel at different temperature and stirring speed. This study was obtained as follows. The sugar content of fresh plum concentrated extract was 55.3~58.3$^{\circ}$Brix, and of the freezing plum concentrated extract was 75.5~70.3$^{\circ}$Brix. In color difference, the freezing plum concentrated extract was more deep black than fresh plum. In change patten of pH, it was decreased as concentration was proceed. The final pH was 2.3~2.2 in fresh plum, and 1.8~2.2 in freezing plum. The total acid content of fresh plum concentrated extract and the freezing plum was 45.4~47.8, 60.3~60.9%, respectively. The content of evaporation at 85$\pm$5$^{\circ}C$ was constant irrespective of stirring speed. The yield of extraction of fresh plum was higher than freezing plum. According to this results, the use of stainless vessel, 50rpm, which gave a highly qualified plum concentrated extract.