Observation on the soaking water and particle size changes during ‘cool powder’ (bedak sejuk) production

Cool powder is a traditional cosmetic product used by locals. the flooding of various cosmetic in the market this domestically produced pastilles has lost its lustre. the production of cool powder,fondly known is bahasa malaysia as bedak sejuk is still using a traditional method which passes from generation to generation. to start the process,the rice grains were soaked in water for at least for two weeks or until the rice gains fully dissolved. the aim of the present study is to observe the changes on the condition of soaking water and particle sizes of the paste produced. local rice grains (indica type) were soaked in the water using a container with lid for 3 months. the soaking process was a semi-batch process whereby in 14 days interval,the soaking water was replaced during this process,it is observed that there is a layer occurred on the top of the container and unpleasant smells detected suggesting natural degradation of the rice via fermentation has happened. the ph values and titratable acidity values which expressed as lactic acid were inversely proportional to each other. the final ph value of fermented supernatant was at ph 3.33 while the titratable acidity value was at 1.13 mg/ml (lactic acid). towards the end of soaking process,it is observed that the particle size of the rice grains decreased but there is slightly increment of weight fraction for rice particles size less than 150 microns. based on these observations,it can be concluded that natural fermentation that occurred has a significant effect on the grains. © school of engineering,taylor’s university.