Effect of Calcium-Added Cellulose Coatings on the Firmness of Plums

칼슘을 첨가한 셀롤로우스 코팅이 자두의 경도에 미치는 효과

  • Song, Tae-Hee (Department of Food and Nutrition, Sookmyung Women's University) ;
  • Kim, Chul-Jai (Department of Food and Nutrition, Sookmyung Women's University)
  • 송태희 (숙명여자대학교 식품영양학과) ;
  • 김철재 (숙명여자대학교 식품영양학과)
  • Published : 1999.02.28

Abstract

Plums (Prunus salicina L.) were coated with calcium-treated methylcellulose (CaMC) and hydroxypropylmethylcellulose-15 (CaHPMC-15). Respiration rate, weight loss, pH and titratable acidity, texture, and sensory characteristics were compared during 8-day storage period at $30^{\circ}C$. Weight loss and respiration rate of plums coated with CaMC and CaHPMC-15 were lower than those of control plums during storage while pH increased and titratable acidity slowly deceased during storage. Mechanical firmness was significantly deceased during storage, in which CaMC and CaHPMC-15-coated plums were harder than the control. Amount of soluble pectin, and pectin esterase and polygalacturonase activities as the markers of softening commonly increased with storage, but both CaMC and CaHPMC-15-coated plums were not found those increases. Sensory evaluation showed that the flesh softening of plums decreased during storage, and that in the coated plums exhibited the harder flesh. In conclusion, introduction of CaMC and CaHPMC-15 coatings on plums decreased respiration rate and contributed to delay of flesh softening, and the significant difference in postharvest storage quality of the both plums were not found between CaMC and CaHPMC-15 coatings.

Keywords

plum;cellulose;coating;calcium;firmness