Nutrient composition of different varieties of full-fat canola seed and nitrogen-corrected true metabolizable energy of full-fat canola seed with or without enzyme addition and thermal processing

Abstract

SUMMARY Samples of 3 varieties of full-fat canola seed (FFCS), Okapi, Opera, and SLM046, were obtained from a local oilseed company, and chemical composition and mineral content of the 3 varieties were determined. Crude protein content of the canola seed ranged from 19.5 to 21.4%, with an average of 20.36 ± 0.85%. Ether extract of the canola seed ranged from 47.3 to 50.4%, with an average of 48.77 ± 0.92%. Composition of the main fatty acids in the oil was determined by gas chromatography. The saturated fatty acid content of Okapi and SLM046 (including palmitic and stearic acids) was very low compared with the unsaturated fatty acid content, and oleic acid (C18:1n-9 cis) constituted the highest proportion of fatty acids (52.56%) in SLM046 (with an average content of 35.84%). Canola seed is rich in C18:3n-3 fatty acids, and the oil of canola seed is an excellent source of α-linolenic acid (8 to 12%). The calcium content of Okapi, Opera, and SLM046 was 1.05, 0.97, and 0.7%, respectively. The average Mg content of canola seed was 0.14 ± 0.007%. Iron content ranged from 45.2 to 51.7 mg/kg in the 3 varieties of FFCS. Zinc content of Okapi, Opera, and SLM046 was 11.1, 17.6, and 13.7 mg/ kg, respectively. Mean content of Mn was 35.57 ± 0.57 mg/kg, and that of Cu was 11.97 ± 0.42 mg/kg in the FFCS samples. The effects of variety, enzyme addition, and thermal processing on the ME of ground FFCS were investigated in a TMEn assay with adult roosters. Ground FFCS samples were heated at 120°C for approximately 3 h in an electric oven. A currently available commercial multienzyme was added to the 3 raw varieties of FFCS at an inclusion level of 0.5%. The average TMEn content of ground FFCS was 5,495 kcal/kg, and a significant difference was found between the 3 varieties of canola seed (P < 0.05). The TMEn content of ground FFCS was not affected by thermal processing or multienzyme supplementation.