Preparation and Characteristics of Mixed Fruit and Vegetable Juices

혼합과채(果菜)쥬스의 제조와 제조방법에 따른 품질특성

  • Kim, Su-Yeun (Department of Food and Microbial Technology, Seoul Women's University) ;
  • Choi, Eon-Ho (Department of Food and Microbial Technology, Seoul Women's University)
  • 김수연 (서울여자대학교 식품 미생물공학과) ;
  • 최언호 (서울여자대학교 식품 미생물공학과)
  • Published : 1998.02.01

Abstract

An experiment to make mixed juices carrying the freshness and other specific characteristics of vegetables and fruits which are useful for the prevention and treatment of various diseases was attempted on the emphases of pretreatment methods, combination of fruits and vegetables, and elimination of microorganisms. Blanch in boiling water prior to extraction for green vegetables, addition of ascorbic acid during extraction for tomatoes and apples, or addition of ascorbic acid after blanch in 3% acetic acid for carrots was effective to keep colors and suspended solids in liquid extract. On the basis of sensory evaluation the extracts from tomatoes, apples. carrots. mallows, watercreses+pine needles, Angelica keiskei Koiz, jujubes and lemons were selected and mixed at the ratio of 3 : 3 : 3 : 1/2 : 1/2 : 1/2 : 1/2 : 1/5. The mixed extracts were pasteurized for 15sec at $96^{\circ}C$ or filtered through a ultramembrane filter. While the centrifuge precipitation and retentates on the membrane filter were autoclaved and combined with ultrafiltrates. The mixed juices showed $pH\;4.07{\sim}4.10$ titratable acidity $66.35{\sim}84.08$, soluble solid $7{\sim}9^0Brix$, reducing sugar $5.42{\sim}6.97%$, glucose $1.96{\sim}2.30%$, fructose $3.46{\sim}4.14%$ and high content of K, Mg and Ca. Ultrafiltration showed better quality scores in color, juice. Peroxidase and microorganisms were inactivated by thermal treatment and ultrafiltration.

Keywords

juice;fruits and vegetables;ultrafiltration;thermal treatment;extraction