Changes of total polyphenolics and vitamin C in acerola during storage and spray drying process

Abstract

Acerola fruit is known to have a high vitamin C concentration. Polyphenolics are also natural oxidants occurring in plants. Understanding changes of these components during storage conditions and processing steps become important. Results of this research showed that there was significant difference in vitamin C and total polyphenolic concentration and three popular varieties of acerola fruits from Tien Giang province. Concentrations of both vitamin C and polyphenolics reduced rapidly during storage at room temperature. After three days, vitamin C reduced about 40% whereas total polyphenolics reduced about 70%. The losses at refrigerated temperature after 3 days were less than 15% and less than 30%, for vitamin C and total polyphenolics, respectively. Frozen storage of the fruit maintained quite well vitamin C and polyphenolics. Acerola pomace juice was concentrated before spray drying and, at the same vacuum pressure, temperatures influenced significantly the retention of vitamin C and total polyphenolics. Optimization of spray drying conditioners including inlet hot air temperatures and added ratio of maltodextrin (drying carrier) was also carried out to obtain high recovery of dry matter, total polyphenolics and vitamin C.