Effect of chemical preservatives on the shelf life of tomato juice

Abstract This research conducted with the fully fresh, ripe and sound tomato (Lycopersicon esculentum Mill.) was collected then washed, peeled, seeds removed and transferred to the juice extractor. Sugar, preservatives were added to the extracted filtrated juice. Then the juice was heated, cooled and bottled for preservation. Tomato juice was prepared with three different treatments. Among the three treatments T1, T2 and T3 sample were prepared with no preservative, Na-benzoate preservative and potassium meta-bisulphite (KMS) preservative respectively. The organoleptic observation of this tomato juice was studied for 60 days storage period. Chemical analysis and sensory tests were carried out during the 30 days at an interval of 15 days to assess the effect of chemical additives on the shelf life of tomato juice. Negligible Change in chemical constituents except vitamin C was observed in the prepared juice throughout the 30 days storage period. Color was gradually faded and slightly off flavor develops at the end of the storage periods. The treatment T2 secured highest score for color, flavor, taste and overall acceptability and ranked as “Like very much” by a taste testing panel. Tomato juice prepared with no preservative (T1) spoiled after 45 days storage and juice prepared with KMS preservative (T3) spoiled after 60 days storage. Total number of viable bacteria was highest in tomato juice treated with no preservative (T1) and KMS preservative (T3). Tomato juice with Na-benzoate preservative (T2) contained least viable bacteria which was better than T1 and T3 sample. Considering all the parameters, Na-benzoate tends to be better additives than potassium meta-bisulphite (KMS) for preservation of tomato juice.