Studies on Stability of Strawberry Drink Stored at Different Temperatures M. ANJUM MURTAZA†, NUZHAT HUMA, JUNAID JAVAID, M. ASIM SHABBIR, G. MUEEN UD DIN AND SHAHID MAHMOOD Institute of Food Science and Technology, University of Agriculture, Faisalabad–38040, Pakistan †Corresponding author’s E-mail: email@example.com, firstname.lastname@example.org
Strawberry drink was stored at room temperature (250C), refrigeration temperature (4-60C) and high temperature (40-450C). The treatments were analyzed for physico-chemical and sensory quality fortnightly for three months. Significant results were obtained for acidity, 0Brix, Reducing sugars and ascorbic acid with regards to the treatments as well as storage. The pH was non significantly affected by treatments; however, storage had significant effect on it. The acidity, 0Brix and reducing sugars increased while pH and ascorbic acid decreased during storage. The acidity and pH changed gradually in all treatments while 0 Brix, reducing sugars and ascorbic acid changed differently and maximum variations were observed in the treatment stored at 40-450C. The storage temperatures and period also significantly affected all the sensory characteristics. On organoleptic evaluation, the treatment stored at refrigeration temperature remained most acceptable and no significant change occurred in it during the storage period. It was found that strawberry drink can successfully be stored at refrigeration temperature on commercial scale manufacturing due to significant stability in colour, flavour and taste. Key Words: Strawberry; Fruit drink; Storage Temperature; Stability
The extreme hot summer weather of Pakistan is mainly responsible for the demand of fruit drinks. There has been a spectacular growth in the consumption of fruit drinks. Fruit juices are now a regular part of the diet of many people. The huge amount of beverages is imported on the expense of foreign exchange which can be saved through production of local drinks. Strawberry belonging to family Rosaceae is the most widely grown berry of the world. It is a small, juicy, nutritious, flavourful and sweet in taste fruit. It is an excellent source of Vit. C. and thought to have tonic, depurative, diuretic, remineralizing and astringent properties (Johnson & Peterson, 1974). Strawberry production in world was 2438 million tons in 1989-91 and 2987 million tons in 1999 and also in Asia was 402 million tons in 1989 and 497 million tons in 1999 (Anonymous, 1999). Edible portion of strawberry contains about 89.9 g water, 0.7 g protein, 0.5 g fat, 8.4 g carbohydrates, 1.3 g fiber, 0.5 g ash, 21 mg calcium, 21 mg phosphorus, 1.0 mg iron, 1.0 mg sodium, 164 mg potassium, 60 I.U. vitamin A, 0.03 mg thiamin, 0.07 mg riboflavin, 0.6 mg niacin, 59 mg ascorbic acid per 100 g (Considine, 1982). Strawberry is widely used as fresh fruit and being a short season and highly perishable fruit can be preserved in the form of pulp. It is mainly used as preserved fruit in juices, dairy and bakery goods etc. Fruit juices are preserved by several methods such as freezing, irradiation, heat processing and use of chemical
preservatives. The last two methods, being most suitable and economical, are employed for preparation and preservation of ready to serve drink but no work has so far been done to follow the changes like colour and flavour losses during storage. Keeping all these factors in view, the present study was conducted to use strawberry pulp for preparation of ready to serve drink with the objective to determine the quality and storage stability of the drink, under different temperatures.
MATERIALS AND METHODS
The strawberries were bought from local market and after thorough washing, treated in steam jacketed vessels at 800C for one minute. The pulp was extracted by means of a fine pulper and cooled at room temperature. Drink...