EFFECT OF METHOD OF PRESERVATION OF PULP ON THE QUALITY OF CARBONATED AND NONCARBONATED BEVERAGES PREPARED FROM PEACH FRUIT

ABSTRACT

Peach pulp preserved by different methods, i.e., processing at 100C for 30 min, potassium metabisulphite (KMS; 2,000 ppm), sodium benzoate (750 ppm) and mixture of KMS and sodium benzoate (1,000 and 375 ppm) had no significant effect on total soluble solids (TSS), acidity, TSS : acid ratio, pH of carbonated as well as noncarbonated beverages. Carbonated beverages prepared from pulp with 750 ppm of sodium benzoate retained significantly (P ≤ 0.05) higher carbon dioxide (CO₂) content and CO₂ gas : volume during storage. Color of the beverages prepared from peach pulp containing KMS was better but the beverages prepared from peach pulp preserved by processing and addition of sodium benzoate were organoleptically more acceptable. Both carbonated and noncarbonated drinks remained organoleptically acceptable throughout storage. Suspension of carbonated beverages was significantly (P ≤ 0.05) higher during storage as compared with noncarbonated beverages.

PRACTICAL APPLICATIONS

Peaches are valued as a table fruit for a short period of time from end of April to end of May. The acceptability and utilization of this fruit can be increased by processing it into delicious carbonated and noncarbonated beverages. This will provide nutritious drink to the consumers and also help in increasing the fruit cultivation resulting in good returns to the growers. This study will also help to give a fillip to the establishment of a peach beverage industry world wide.     

Estimation of sugars in milk by HPLC and its application in detection of adulteration of milk with soymilk

A high-performance liquid chromatography method is described for the detection of adulteration of milk with soymilk, based on separation of sugars on NH₂ column and their detection by refractive index detector. Sugars were extracted with 20% acetonitrile in the presence of Carrez solutions and quantified. Recovery of added raffinose to soymilk was 96.3%. Owing to relative high concentration of lactose in milk or adulterated milk, lactose peak was very broad and spread to retention time corresponding to sucrose and raffinose. However, stachyose peak remained well separated. Presence of stachyose peak in milk can be used for the detection of adulteration of milk with soymilk and the method can detect upto 5% soymilk in milk.