Microbiological and Sensory Profile of Soymilk Based Juice Treated with Liquid Extract of A. Danielli

摘要

The microbiological and sensory profile soymilk-based juice treated with aqueous extract of Aframomum danielli (1%-3%-w/v) and stored at 272C for twenty four weeks were examined. Synthetic additives/preservatives, which have been in use over the years, are more expensive and mostly imported with hard earned scarce foreign exchange. Adequate research work into the production and utilization of indigenous food additives on a large scale has not been undertaken in developing countries. This work was therefore planned to ascertain the usefulness of extracts of A. danielli, a local spice, in stabilizing the microbiological quality of soymilk-based juice. Standard methods were used for the production of juice samples from pineapple, orange, carrot and milk from soybeans. They were blended together in equal proportion and thereafter treated with A. danielli extract (1.0% to 3.0%) and stored at 27+2C for twenty four weeks. Infrared spectrophotometer was used to identify functional groups in Aframomum danielli and hence the active components responsible for the stability of the juice. Standard AOAC method was used for microbiological analysis of treated and untreated samples. Consumer evaluation of juice samples was done using analysis of variance (ANOVA). Some of the active components of the spice identified are 4-amino-acetophenone, N,N-dimethyl-2-chloroacetoacetamide, 3-beta-acetoxy-5-etienic acid, 6,10-dimethylundeca-5,9,-diene2-one, Phenyl-3-buten and 4-Phenyl butanone. There were significant differences in the microbial counts of the treated and untreated samples. Treated samples experienced little or no growth over the period of storage. The results validate previous reports that A. danielli extract has great preservative potentials. There were significant differences (P < 0.5) for colour and overall acceptability of the samples. When A. danielli extract was added to soymilk-based fruit juice, the microbiological and sensory qualities were found to be better preserved than that of the untreated samples.