Effect of different preservation techniques on chemical, microbial and functional properties of Palmyrah dried seed shoot flour

Abstract

Palmyrah (Borassus flabellifer) seed shoot flour has many nutritional values and it contains a high amount of starch. It is widely utilized in the preparation of starch based food products. Since these are seasonal products, most of them are spoiled and wasted due to microbial and insect damage. The aim of this research was to increase the shelf life by using suitable preservation methods. Vacuum packaging, roasting (180 0 C, 10 min), fumigation using phosphine gas (1 gm -3 , 4 days) and addition of preservative (Sodium Metabisulphite, 200ppm) were the treatments done to increase the shelf life of dried seed shoot flour. Microbial stability was compared through variations in Total Plate Count and Yeasts and Molds count for control and all treated seed shoot flour for one year. Chemical (Moisture, Ash and Starch) and functional properties (Water absorption capacity, Bulk density, Foaming capacity, Foam stability and Swelling power) were tested to assess the effect of different treatments. Among the treatments, vacuum packaging contains the less Total Plate Count (6.83±0.01 log CFU/g) and Yeasts and Molds count (3.0±0.1 log CFU/g) after the storage period of one year compared to other treatments. Bulk density was affected by all the treatments applied and compared with control. Fumigation had a significant effect on moisture content (10.76±0.45 %) and Roasting affected the water absorption capacity (219.21 ± 0.42 %) and swelling power (3.82 ± 0.02) of flour positively and forming capacity (54.12 ± 0.04 %) negatively. Based on the results observed vacuum packaging was identified as the best method for preservation of Palmyrah dried seed shoot flour.