Pentosans in Prepress-Solvent and Solvent Processed Rapeseed Meal

In studies of factors which cause rapeseed meal to have a lower metabolizable energy value than soybean meal Lodhi et al. (1969) reported that the “available carbohydrate” in rapeseed meal, whether measured chemically or by chick bioassay was less than in soybean meal. During the course of further studies in our laboratories the pentosan content of fifteen samples of rapeseed meal was determined by the A.O.A.C. (1965) method. The results, presented in Table 1, show that eight samples of prepress-solvent meal had an average pentosan content of 8.4% and seven samples of solvent meal had an average pentosan content of 8.3% with an overall average for all meals analyzed of 8.3%. Bolton (1957) reported that the pentosan content of soybean meal was 5.6%. Since the digestibility of pentosans by young chick is negligible (Bolton, 1955), the higher content of this fraction in rapeseed than in soybean meal would appear to…