Investigation of rice quality milling in abrasive and blade whiteners in terms of breakage percentage and degree of milling

Reduction of rice losses is very important. In this study, appropriate moisture contents for milling of three common rice cultivars were determined in abrasive and blade whiteners. To this end, a factorial test based on a randomized complete block design with three replications was carried out in two milling systems: abrasive and blade whiteners, on three paddy cultivars: Sorkheh, Sazandegi, and Tarom and at four moisture contents: 8, 10, 12 and 14% (on wet basis). The paddy cultivars were dried and converted into white rice in abrasive and blade systems. In each treatment, the rice-breakage percentage, the DOM, the working capacity and the power consumption of each system were measured. The results showed that cultivar Sorkheh had the lowest rice-breakage rate. In addition, the mean breakage rate and DOM were significantly lower in the abrasive whitener than in the blade whitener. Based on results, most appropriate milling moisture contents for the cultivars Sorkheh, Sazandegi, and Tarom were 10, 12, and 10%, respectively, in the abrasive system, and 10, 12, and 12%, respectively, in the blade system. The working capacity and power consumption in the abrasive system were 1.7 and 3.43 times as much as those in the blade system, respectively.