Effect of chemical additives on the shelf life of tomato juice.

摘要

Effects of chemical additives were investigated on the shelf life of tomato juice. Shelf life of tomato juice containing 3 different chemical additives (potassium meta-bisulphate (KMS), sodium benzoate and sorbic acid) was studied over a 60 day storage period at room temp. Chemical analysis and sensory tests were carried out at intervals of 15 days. Negligible changes in chemical constituents, apart from vitamin C, were observed in the prepared juices throughout the 60 day storage period. Colour gradually faded and off-flavour developed at the end of the storage time. Additives and storage period had significant effects on percentage acidity. Spoilage occurred after 60, 45 and 30 days in tomato juice containing sodium benzoate, KMS and sorbic acid, respectively. Total counts of viable bacteria were highest and lowest in tomato juice containing KMS and sodium benzoate, respectively. There were no significant differences among juices containing the 3 chemical additives in respect to colour and acceptability. Overall, results suggest that sodium benzoate is more effective than KMS or sorbic acid for the preservation of tomato juice.