Effects of feeding outer bran fraction of rice on lipid accumulation and fecal excretion in rats.

Outer bran fraction of rice (OBFR) contains higher concentrations of crude fiber, γ-oryzanol, and phytic acid compared to whole rice bran (WRB). In this study, we examined the effects of feeding OBFR on lipid accumulation and fecal excretion in rats. Twenty-one male rats at seven-week-old were divided into a control group and two treatment groups. The control group was fed a control diet, and the treatment groups were fed OBFR- or WRB-containing diet for 21 days. There was no significant difference in growth performance. Feeding OBFR diet increased fecal number and weight accompanied by increased fecal lipid content, while it did not affect mRNA expressions encoding lipid metabolism-related protein in liver. In addition, feeding OBFR-diet decreased the abdominal fat tissue weight and improved plasma lipid profiles, while WRB-containing diet did not affect them. These results suggested that feeding OBFR-diet might prevent lipid accumulation via enhancing fecal lipid excretion in rats.

Life cycle assessment of animal feeds prepared from liquid food residues: a case study of rice-washing water.

Life cycle assessment (LCA) was used to compare the greenhouse gas (GHG) emissions and energy consumption of three methods used to produce animal feed from concentrated rice-washing water (CRW) and disposing of the rice-washing water through wastewater treatment. Four scenarios were compared using LCA: (i) producing concentrated liquid feed by centrifugation (CC) of CRW with wastewater treatment and discharge of the supernatant, (ii) producing concentrated liquid feed by heating evaporation (HC) of CRW, (iii) producing dehydrated feed by dehydration (DH) of CRW, and (iv) wastewater treatment and discharge of nonconcentrated rice-washing water (WT). The functional unit (FU) was defined as 1 metric ton of rice washed for cooking or processing. Our results suggested that the energy consumptions of CC, HC, DH, and WT were 108, 322, 739, and 242 MJ per FU, respectively, and the amounts of GHG emissions from CC, HC, DH, and WT were 6.4, 15.8, 45.5, and 22.5 kg of CO equivalents per FU, respectively. When the produced feed prepared from CRW was assumed to be transported 200 km to farms, CC and HC still emitted smaller GHGs than the other scenarios, and CC consumed the smallest amount of energy among the scenarios. The present study indicates that liquid feed production from CRW by centrifugation has a remarkably reduced environmental impact compared with the wastewater treatment and discharge of rice-washing water.