EFFECT OF COMBINATION MICROWAVE AND OVEN DRYING ON THE CHEMICAL PROPERTIES OF DIFFERENT RIPENESS CRUDE PALM OIL

Abstract

Small crude palm oil mill in Thailand produced the low quality of crude palm oil by using oven
drying to dry palm fruits for 14-16 hours. So, the aim of this research is to replace oven drying by using the
combined microwave and oven drying to dry palm fruits at different ripeness for 3-4 hours. The effects of
combined methods on the chemical properties of crude palm oil are evaluated and compared the properties
with premium crude palm oil. The experiments of study followed this detail. The raw materials were 18, 20,
22 and 24% of oil content consisted in oil palm bunches. In experiment, 1 kg of each sample was heated at 850
watt for 10 minutes in microwave followed with oven drying for 3 hours. Heated palm fruits were further
separated the mesocarp from kernel seed. The mesocarp was further pressed by screw press to obtain crude
palm oil. The oil was analyzed its chemical properties in term of free fatty acid (FFA), deterioration of
bleachability (DOBI), carotene content, vitamin E content, iodine value (IV) and peroxide value (PV). The
results showed that all of oil palm fruits ripeness can produce a premium crude palm oil with low free fatty
acid content and high DOBI value.