Effect of moisture content of paddy (Phka Rumduol) on the quality of white rice (Oryza sativa L.)

This study evaluated the impact of paddy moisture content on the quality parameters of white rice produced from Cambodia's premium fragrant variety, Phka Rumduol (Oryza sativa L.). A completely randomized design (CRD) was employed to evaluate the effect of moisture content on rice quality. Paddy samples were adjusted to four target moisture levels (10%, 12%, 14%, and 16%) and subsequently milled under controlled conditions. The CRD ensured unbiased allocation of samples across all treatments, minimizing experimental error during both moisture conditioning and milling processes. The results showed that moisture content had a significant effect (p < 0.05) on all measured quality parameters. Paddy at 14% moisture content produced the best results, with a head rice yield of 63.46 ± 3.00%, and a broken rice percentage of only 4.86 ± 0.65%. Grain appearance was also well preserved, with rice bran yield of 10.67 ± 0.42%, rice husk yield of 18.52 ± 2.72%, and yellow kernels averaging just 0.79 ± 0.02%. In contrast, moisture levels below 12% increased kernel brittleness, leading to breakage rates as high as 26.28 ± 0.92%, while levels above 16% caused grain deformation and discoloration. These findings highlight the importance of maintaining paddy moisture at 14% prior to milling to optimize recovery and preserve the high quality of Phka Rumduol rice. The study provides practical guidance for Cambodian rice processors aiming to improve product quality and strengthen competitiveness in international markets.