Development of a Gasoline Food-Grade Magnetic Hammer Mill and Estimation of Milling and Energy Consumption Pattern of Some Selected Food Materials

This study was aimed to develop a laboratory-scale gasoline food-grade magnetic hammer mill and to estimate the milling efficiency, milling yield, milling time, energy consumption and energy intensity of some selected food materials (soybean, rice and cassava flakes). The hopper, shaft, sieve and hammers of the gasoline food-grade magnetic hammer mill are made of stainless steel and the structural base is made of mild steel. The cost of developing the gasoline food-grade magnetic hammer mill was ₦ 149,000. Cassava flakes were observed to have the highest milling yield (940 g), lowest energy consumption (0.94 MJ), energy intensity (0.94 MJ/kg) and the highest milling efficiency (94 %) while soybean was observed to have the longest milling time (5.86 mins). The developed gasoline food-grade magnetic hammer mill could be adopted for milling different food materials but its performance varies based on the food material

Evaluation of rice milling quality and energy requirement via a developed vibratory rice grader

In the modern way of processing rice, rice is usually parboiled before milling operation and grading is one of the milling operations required to classify rice into different grades of importance viz. the head and broken rice.  In this study, a vibratory rice grader was developed. The effect of processing conditions on the milling quality (milling recovery, head milled rice and broken rice), grading time, energy requirement and energy intensity were evaluated. The soaking time (4 – 6 h), steaming time (30 – 40 mins) and rice variety (FARO 15, FARO 60 and FARO 62) were interacted using Taguchi experimental design (L933). Standard equations were used to evaluate the effect of processing conditions on the milling quality, energy requirement and energy intensity of the rice grader. Milling recovery ranged from 53% to 70%, head milled rice (41% - 67%), broken milled rice (3% - 12%), grading time (4.4 – 5.8 mins), energy requirement (2.632 MJ to 2.649 MJ) and energy intensity (1.20 – 1.58 MJ/kg). An increase in soaking time and steaming time increased the grading time, milling recovery, head milled rice, energy requirement and energy intensity but reduced the broken milled rice.  The estimated cost of the developed vibratory rice grader was $152. This study provides valuable information on a simple way of designing and developing a rice grader that could be adopted for grading rice into whole rice or head rice and broken rice