Production of Sugar-Beating Sap from Nipa Palm in Pak Phanang Basin, Southern Thailand

Abstract

In the Pak Phanang Basin of southern Thailand, the Nipa palm (Nypa fruticans wurmb.) grows naturally in an area of approximately 3,200 ha. Economically, coastal villagers in the basin earn their income from the palm in several ways, most importantly in Nipa sugar production. The production of 1,030 kg/ha of sugar per month with 8 tappable months per year is standard for this area. Nipa sap is the source of sugar, its content was reported to be 14 to 17 percent sucrose. Sap is generally collected from the mature fruit stalk (infructescence) after the almost full-grown fruiting head of the plant has been cut. Sap flow, however, depends on preparationof the stalk. To stimulate the flow, the stalk is beaten 40-50 times daily for 3 days and then this is stopped for 10 days. The beating cycles are then repeated consecutively for a second and a third time. Tapping begins by removing a thin end slice of the fruit stalk about 1-2 mm thick. The freshly cut stalk end is inserted into a hole in a bamboo container to collect the sap. A skilled tapper is able to tap as many as 100 stalks per day. It is estimated that a normal tapped stalk can produce about 0.7 l of sap daily. Research on sap flow stimulation has shown a relation between varying levels of beating the stalk and rates of sap flow. The conversion rate of sap to sugar by boiling and evaporation is on average, 100 l sap: 21 kg sugar.