Production of Instant Fruit and Vegetable Juice by Spray Dryer and Microwave—Vacuum Dryer

Abstract

The objective of this research is to study the production of instant fruit and vegetable juice using spray dryer and microwave—vacuum dryer. The research was divided into 2 steps; optimizing the drying conditions and improving the solubility of instant fruit and vegetable juice. The mixed juice 01 orange juice : carrot juice : lime juice of 49 : 34 :17 by volume with the total soluble solid of 16^OBrix was used as a raw material. The fruit and vegetable juice was dried by spray dryer with the inlet temperature of hot air of 100, 110 and 120C and maltodextrin concentration of 13, 16 and 19%. The experimental results showed that drying with the inlet temperature of hot air of 110^OC with maltodextrin concentration of 16% gave the product with good sensory, physical. and chemical properties. Fruit and vegetable juice was also dried by microwave—vacuum dryer with the pressure of 160 torr and electrical power of 210 watt. The results showed that juice with  maltodextrin concentration of 16% gave the product with good sensory, physical, and chemical properties. Moreover, it was found that drying conditions significantly affected the bulk density, moisture content, vitamin C content and color of instant fruit and vegetable juice at 95% confidence level. Spray drying foam technique using 1% soy protein isolated can improve solubility and dispersibility of the spray dried product, while agglomeration technique with 95% ethyl alcohol improve solubility and dispersibility of both spray dried and microwave—vacuum dried products.

Keywords : Spray Dryer / Microwave—Vacuum Dryer / Spray Drying Foam / Agglomeration / Instant Fruit and Vegetable Juice