Innovative technologies for sago starch production and utilisation in Papua New Guinea

Papua New Guinea holds about 40 percent of the wild sago palm stands with more than 20 cultivars. Some of the local (Sepik) names for these cultivars are listed. Sago palms are not being properly managed to identify the highyielding ones. The steps needed to improve the agronomic properties of the palms were discussed. Sago starch is the main product of the palm and in the absence of any measureable parameter, the palms to be processed are chosen by experience and in most cases, the starch yield is low. Starch extraction is mainly done using traditional procedures. Debarking is done by bush knives and the pith is pulverised using either an adze-like steel tipped tool or a nail-studded wooden board (rasp). The particle size distribution of the ground pith is varied and about 40 percent is below 2 mm. A rotary rasper yielded more than 90 percent of particles below 2 mm but a diesel-or electric-powered motor is required to shorten the operational time. The starch is washed off the pith manually and the contact time and water:pith ratio are normally judged arbitrarily. To increase the starch yield, washing ought to be done more than once and for a good starch quality, potable water is required. Tested procedures and recommendations for a good starch yield were itemised. In Papua New Guinea, traditionally-processed sago starch is mainly used for human foods and 14 of such foods were described using flowcharts. With these foods, the starch is either dry or wet-heated and simple technologies are usually employed. In view of the low protein content of sago starch, certain protein-rich ingredients such as fish and peanuts have found wide use. Critical areas in the traditional procedures were identified for improvement to extend the keeping quality of the starch and resulting products. Sago starch can find uses in the local food industry but for its present quality and because of the local industry relatively low level of operation. The bakery, cannery and snack food sectors were identified as potential users. Extrusion cooking technology offers a route. A simple procedure for the manufacture of a sweetener from sago starch using germinated maize needs to be explored for increased utilisation of sago starch in Papua New Guinea.