Comparison of Juice Extraction Methods from Fresh and Frozen Mayhaw (Crataegus opacaHook.) Fruit

Abstract

ABSTRACT The highest juice yields were obtained from a combined interaction of temperature, maceration, application of pectolytic enzyme, and previously frozen fruit. Freezing mayhaw fruit prior to juice extraction increased juice yield regardless of the method used in extraction. The average juice yield obtained from previously frozen fruit was 157% higher than when using fresh fruit. Maceration of fruit plus the application of heat to the fruit pulp prior to juice expression had a significant influence in juice extraction efficacy for both fresh and frozen fruit. When heat was applied to fruit pulp prior to expression, juice yields increased from 31.4% for cold press extraction and 63.5% for hot press extraction. Application of a pectolytic enzyme to preheated fruit pulp increased total soluble solids (TSS) in extracted juice by 15% when utilizing frozen fruit compared to hot-press extraction without enzymes yield of 6.6%. There was no significant difference in TSS recovered by either fresh or frozen cold press methods without enzymes. All steam extraction methods utilizing fresh fruit had a lower percent recovery of total acid (TA) than when a pectolytic enzyme was added to fresh fruit before extraction. There were no significant differences in juice pH regardless of whether fresh or frozen fruit were used. Recovery of both TSS and fructose was significantly increased when pectolytic enzyme was added to fresh fruit. The lowest recovery of fructose was from steam extraction for both fresh and frozen.