Changes in physico-chemical properties of wild date palm (Phoenix sylvestris) sap over its peak production period

Phoenix sylvestris Roxb. sap plays an important role in the diet of inhabitants of tribal area of West Bengal. In the present study the sap of 15 to 20 years old trees was collected separately during December to February, 2012-13 and 2013-14 from Haringhata block in Nadia district of West Bengal (India). The results indicated that the specific gravity of the sap changed little from 1.041 to 1.052 during December to February while the total soluble solids (TSS) were found maximum during February (14.33%). Chemical composition analysis revealed that a sap with highest pH (6.75) and lowest acidity (0.04%) was found during January while the sugar/acid ratio decreased from 325.47 during January to 42.93 during February. The sap of wild date palm had the maximum ascorbic acid content (18.75 mg/100 ml) during December while it decreased to 14.58 mg/100 ml during January and 13.75 mg/100 ml during February. Alcohol content was highest during February, whereas it decreased gradually during January and December. The sap also contained ample amount of phenol ranging from 67.90 mg/100 ml to 81.47 mg/100 ml. Total sugar content was greater during February (12.50%) than during January (11.72%) and December (11.37%). The overall results revealed that the wild date palm sap is a good nutrient supplement and is opulent in TSS, vitamin C and carbohydrate. So the sap can be used as a good alternative source of health drink and to alleviate malnutrition of poor tribal population of West Bengal (India)