饲料的粗脂肪水平和调质温度对颗粒饲料硬度的影响

本试验旨在探究粗脂肪水平和不同调质温度对颗粒饲料硬度的影响。在粗脂肪水平分别为3.37%、4.0%和4.65%时,调质温度为60℃、70℃和80℃时进行制粒为9种饲料,测定制粒后不同风干时间颗粒饲料的硬度、颗粒耐久性指数(PDI)等加工质量指标。结果表明:对于未经风干的颗粒饲料,当调质温度为60℃,当粗脂肪含量由3.37%提高到4.65%时,颗粒饲料硬度降低了30.6%(P0.05);而当粗脂肪含量为3.37%,调质温度从60℃升高到80℃,颗粒饲料硬度升高了138.5%(P0.05);与粉料相比,调质温度为60℃、70℃和80℃时颗粒饲料淀粉糊化度分别显著增加了67.9%、88.1%和130.5%(P0.05);随着颗粒饲料风干时间的延长,饲料水分降低,颗粒硬度却随之增加(P0.05);PDI与颗粒硬度呈显著的正相关(R~2=0.954,P0.05)。综上可知,颗粒饲料的粗脂肪含量、调质温度和水分含量均会影响颗粒饲料的硬度。在实际生产过程中,可通过提高调质温度,降低饲料中粗脂肪或水分含量,进而提高颗粒饲料的硬度。

Effect of Ether Extract and Conditioning Temperature on the Hardness of Pellet Feed

The object of the study was to investigate the effect of conditioning temperature and ether extract on pellet feed hardness. In this research, the conditioning temperature of 60℃,70℃, and 80℃ were set, and 3 diets with 3.37%, 4.00% and 4.65% ether extract were used to process 9 kinds of pellet feed, to analyze the moisture, hardness, pellet durability index(PDI) and gelatinization degree of starch. The results suggested that: The hardness of pellet feed without drying was reduced 30.6%when the ether extract content of feed was increased from3.37% to 4.65% at 60℃(P<0.05).The hardness of pellet feed with 3.37%of ether extract content was increased 138.5%when conditioning temperature was increased from 60℃ to 80℃(P<0.05). Comparing with powder, the starch gelatinization degree of pellet feed at the conditioning temperature of 60℃, 70℃ and 80℃were increased 67.9%, 88.1% and 130.5%, respectively(P<0.05). The moisture of pellet feed was decreased with the prolongation of air drying time and the particle hardness was increased(P <0.05); PDI had a significant positive correlation with the particle hardness(R~2=0.954, P<0.05). The ether extract content, the moisture and conditioning temperature were affected significantly on the hardness of pellet feed. The particle hardness of pellet feed was increased with the increasing of conditioning temperature and the decreasing of feed ether extract content or moisture in the practical production.