Effect of Freeze-Drying Pressure and OperatingTime on Mass Balance and Characteristics of Freeze-Dried Mango Slices

Abstract

Mango (Mangifera indica L.) is one of the local foods in Indonesia, which has high water and sugar content and is vulnerable to heat conditions. This study aims to determine the effect of freeze-drying time (t) and pressure (P) on mass balance and characteristics of dried mango slices produced through treatments based on time 13 h and 17 h and pressure 25 Pa, 30 Pa, and 35 Pa, with temperature constant -50 oC. Freeze-dried mango was calculated for mass balance and analyzed for water content, color, and hedonic test. The mass balance yield was around 82.47 % of the product wasted during the drying process, and the product yield was approximately 17.53 %. The water content value in the mango from all treatments was 6.17 % to 7.13 %, which was < 31 % as desired by the Indonesian National Standard (SNI—Standar Nasional Indonesia) for dried fruit products. The results showed that the colors changed in Treatment 2 (17 h and a pressure of 35 Pa). The hedonic test showed that Treatment 1 (13 h and a pressure of 35 Pa) was the best, but Treatment 2 (17 h and a pressure of 25 Pa and 30 Pa) yielded the best texture.