Authors : Eun Ju Seog , Kyoung Suck Sohn and Jun Ho Lee
Abstract: Clarified apple, carrot and orange juices were prepared using ultrafiltration and their single and blend juices were further concentrated using ultrafiltration, freeze-drying and rotary evaporation. Effect of concentration methods on the color of concentrated single and blend juices was investigated. The color properties of concentrated single and blend juices showed that heat concentrated samples using rotary evaporator had significantly lower L*-values than those of the other concentration methods regardless of juice type (i.e., apple, orange or carrot) and blending (p<0.05). The a*-values of heat concentrate juices were lower and b* values were higher than those prepared by UF and vacuum freezing in general. Concentrated carrot or carrot rich juices showed equal or relatively higher L*-values, while concentrated apple or apple rich juices showed equal or lower L*-values than those of the other single and blend juices regardless of concentration methods. Concentrated carrot or carrot rich juices showed relatively lower b*-values in general, while concentrated apple or apple rich juices showed higher b*-values than those of the other single and blend juices in UF and vacuum-freeze concentration.
Eun Ju Seog , Kyoung Suck Sohn and Jun Ho Lee , 2006. Color Characteristics of Concentrated Single and Blend Juices as Influenced by Concentration Methods. Journal of Food Technology, 4: 143-146.