Formulation and development of palmyrah(borassus flabellifer l) fruit pulp based milk drink

Abstract

Palmyrah (Borrasus flabellifer L) fruit is a nutritious and functionally beneficial fruit with unique organoleptic properties. Wastage of this seasonal fruit is prominent in Sri Lanka during peak season due to less industrial utilization. The availability of ready to serve drinks using fruits like Palmyrah gives a good option to consumers who prefer nutritional and healthy drinks. This study was conducted to give value addition to Palmyrah fruit pulp in the form of fruit pulp based milk drink to promote its utilization. Acid application and heat treatment were done to fruit pulp prior to incorporation in order to reduce and mask its bitterness. Pulp was extracted manually from well ripen fruits and treated with 0.2% of citric acid which was found to be the optimal percentage for this product, considering the pH change of pulp and heat- treated at 85oC for 30 minutes to achieve bitterness reduction. The formulation of pulp based milk drink included twelve treatments with three levels (12%,15%,18%) of fruit pulp, two types of stabilizers [Pectin and Carboxy Methyl Cellulose(CMC)], and two types of sweeteners (Cane sugar, Palmyrah sugar). Each sample was heated at 85oC for 20 minutes. The best formulation was selected through sensory evaluation by performing 9- point hedonic scale test using 20 semi-trained panelists and the results were statistically analyzed. The most preferred sample among the twelve treatments contained 15% of fruit pulp, 6% of Palmyrah sugar and 0.2% of CMC stabilizer. Homogenization was done at 10, 000 rpm for 7 minutes for the developed formula to prevent sedimentation and layer separation. The proximate analysis revealed that developed formula is nutritionally superior than commercial sample. The finalized product contained 4.4% of protein, 3.2% of fat, 0.78% of ash, 10.11% of total sugar, 0.29g/100ml of vitamin C and 15.98 GAE mg/L of total phenolic content. The developed product did not show any microbial growth in the analysis of total plate count throughout 4 weeks of storage in the refrigerator.