Effects of Steam Flaking on Starch Characteristics,Nutrient Contents,Cornell Net Carbohydrate and Protein System Components,in Vitro Gas Production Parameters and Molecular Structure of Corn
This experiment was conducted to investigate the effects of steam flaking on the nutritional character-istics,in vitro rumen fermentation and molecular structure of corn.A completely randomized design was adopt-ed,divided into two treatments,which were untreated corn(UC)and steam-flaked corn(SFC),each treat-ment contained 3 replicates.The starch characteristics,nutrient content,Cornell net carbohydrate and protein system(CNCPS)components,in vitro gas production parameters and molecular structure of untreated corn and steam-flaked corn were measured,and the correlation of corn molecular structure with CNCPS components and in vitro gas production parameters were analyzed.The results showed as follows:1)the starch content,starch gelatinization degree,amylose content and total carbohydrate,intermediately degraded carbohydrates(CB1),intermediately degraded protein(PB2),slowly degraded protein(PB3),undegradable protein(PC)contents of steam-flaked corn were significantly higher than those of untreated corn(P＜0.05),and the starch relative crystallinity and ether extract(EE),neutral detergent fiber(NDF),acid detergent fiber(ADF),crude protein(CP),rapidly degraded carbohydrates(CA),slowly degraded carbohydrates(CB2),non-pro-tein nitrogen(PA),rapidly degraded protein(PB1)contents were significantly lower than those of untreated corn(P＜0.05).2)The 1 to 4 h gas production of steam-flaked corn was significantly higher than that of un-treated corn(P＜0.05),and the slow gas production(b)and potential gas production(a+b)were significant-ly lower than those of untreated corn(P＜0.05).3)The total carbohydrate area and carbohydrate 3rd peak height and area of steam-flaked corn were significantly higher than those of untreated corn(P＜0.05),and the amide Ⅰ,amide Ⅱ area and height and α-helix,β-sheet were significantly lower than those of untreated corn(P＜0.05).4)The amide Ⅰ,amide Ⅱ area and height and α-helix,β-sheet of protein molecular structure in corn were significant positively correlated with the CA,PA and PB1 contents(P＜0.05),and significant nega-tively correlated with the CB1,PB2 and PC contents(P＜0.05).In conclusion,the steam-flaking beneficial for enhance the total carbohydrate area and carbohydrate 3rd peak height and area,and reduce the height and area of protein structures,thereby increase the carbohydrate content,promotes the early fermentation and nutri-ent utilization in rumen.The molecular structures of corn are correlated with CNCPS components and in vitro gas production parameters.[Chinese Journal of Animal Nutrition,2024,36(3):1964-1976]
steam flakingcornCNCPSin vitro gas productionmolecular structure
万方数据
维普
