Enzymatic modification of canola meal (CM) is a potential method to enhance its nutritional value as it can depolymerize nonstarch polysaccharides (NSP) and mitigate its potential antinutritive properties. Based on the previous studies, pectinase A (PA), pectinase B (PB), xylanase B (XB), and invertase (Inv) were used for the enzymatic modifications. The highest NSP depolymerization ratio was obtained when 4 g/kg of each PA, PB, and XB, and 0.2 g/kg of Inv were used during 48 h incubation at 40 °C. In the current study, changes in pH, simple sugars, sucrose, oligosaccharides, and NSP contents during the enzymatic modification (CM+E) of CM were measured and compared to Control (CM) without enzymes addition or with the addition of bacteriostat sodium azide (CM+E+NaN3). The results showed that spontaneous fermentation occurred during incubation. After incubation, the pH of the slurry decreased, lactic acid was produced, phytate disappeared, and the concentration of simple sugars decreased substantially. The NSP of the slurry was progressively depolymerized by the enzyme blend. The chemical composition and nutritive value of enzymatically-modified CM (ECM) were evaluated. Ross 308 broilers were randomly assigned to 18 cages of six birds each for the standardized ileal amino acid digestibility (SIAAD) and nitrogen-corrected apparent metabolizable energy (AMEn) assay. A corn/soybean meal-based basal diet formulated to meet Ross 308 breeder recommendations and two test diets contained 70% of the basal diet and 30% of CM or ECM, respectively, were fed to Ross 308 from 13 to 17 d of age. No difference was observed between SIAAD of CM and ECM. The AMEn value of ECM was 2118.0 kcal/kg on a dry matter basis which was 30.9% greater (P < 0.05) than the CM.
Keywords: carbohydrase; enzymatically-modified canola meal; lactic acid; nitrogen-corrected apparent metabolizable energy; nonstarch polysaccharides; standardized ileal amino acid digestibility.
Canola meal (CM) is a coproduct of canola oil production which is a valuable protein source for animal nutrition. Its nutritive value can be further enhanced through enzymatic treatment. This process also triggers the fermentation, which results in a decrease in slurry pH, production of lactic acid, disappearance of phytate, and reduction in simple sugars concentration. Moreover, the enzyme blend progressively depolymerized the nonstarch polysaccharides (NSP) of the slurry. No difference was observed between standardized ileal amino acid digestibility of CM and enzymatically-modified CM. The enzymatic modification improved the nitrogen-corrected apparent metabolizable energy of CM for broiler chickens by 30.9%.
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