Influence of palm olein on protein utilisation in the growing rat

In view of our preliminary findings that refined palm oil (RPOL) enhanced protein utilisation, and because of the growing importance of palm oil in human diets, two separate studies were conducted. The first study aimed to investigate the effect of the palm oil source and fraction on protein utilisation, as determined by net protein utilization (NPU) in growing rats. The second study aimed to investigate the influence of the dietary concentration of one particular palm oil fraction, refined palm olein (RPO) on net protein utilisation. The fat source of each of the semi-purified diets was as follows: crude palm oil (CPO), refined palm kernel oil (RKO), refined palm olein (RPO), refined palm stearin (RPS), and refined palm oil (RPOL). A sixth control group was offered an identical diet but with olive oil (OO, control) as the fat source. Both the oil source (P < 0.01) and the oil level (P < 0.05) influenced NPU in rats. NPU values were generally higher for rats given the RPO-containing diets, particularly at the 20% dietary level (P < 0.01) compared to the diets containing ground nut oil (GNO). The results of these two experiments indicate that RPO influences protein metabolism specifically at a concentration of at least 20% in the diet. This may suggest that RPO is superior to GNO as a source of fat for the rehabilitation of malnourished children. Human trials notably during the rehabilitation of malnourished children may therefore be the next step in this line of research.