陈玉米粉碎粒度的研究

Study on grinding particle size of corn

为了探究玉米品种、储存时间和条件、粉碎机筛片直径对陈玉米粉碎粒度的影响,试验采集了国库储存不同年份的29个陈玉米样品、19个东北单一品种陈玉米样品,以及不同储存温度的玉米,通过孔径为3.60 mm和6.00 mm的筛片进行粉碎,采用筛分法测定粒度。结果表明:(1)不同储存时间的国库玉米粉碎粒度随储存时间的延长成波动变化,但无显著差异(P>0.05);(2)储存在相对温度低的玉米粉碎粒度高于储存在相对温度高的玉米;(3)粉碎粒度与玉米粗蛋白质、粗脂肪、总淀粉和粗纤维含量没有显著的相关性(P>0.05),但与玉米NDF、ADF含量呈现显著的负相关(P<0.05);(4)筛片孔径显著影响陈玉米粉碎粒度(P<0.01),相对于3.60 mm孔径的筛片,使用6.00 mm孔径筛片粉碎玉米能大幅度提高颗粒度大于2 000μm玉米颗粒的比例(几乎提高8倍),并降低颗粒度小于850μm玉米颗粒的比例。由此可知,长时间储存和高温储存导致玉米脆性增加、粉碎粒度变小,提高粉碎机筛片直径可以增加陈玉米的粉碎粒度。

This experiment was conducted to study the effect of corn varieties, storage time, storage con-ditions, the screen size of grinder on grinding particle size of corn. Twenty-nine stored corn sam- ples were collected from Chinese national barn, nineteen stored commercial corn samples were collected from northeast of China and corn sampies which were stored in different temperature condition were crushed and sieved through screens of two different pore size（3.60 mm and 6.00 ram）. After mixing the cracked corn, we calculated their particle size. The results showed that ① The corn particle size fluctuated with the increasing of storage time, however, there was no significant effect of storage time on grinding particle size of corn （P〉0.05）; ② The grinding particle size of corn which were stored in lower temperature was greater than the corn stored in higher temperature; ③ The corn grinding particle size has no relationship with the content of the crude protein, crude fat, total （P〈0.01）. Compared with 3.60 mm screen, 6.00 mm screen could greatly improve （almost 8 times high- er） the proportion of corn granule whose particle size were more than 2 000 μm（P〈0.01）, and decreased that one whose particle size were less than 850 μm. These results indicated that the long storage time and high temperature storage environment led to the increase of brittleness of corn and the decrease of corn particle size, and the grinding particle size of the corn could be increased by increasing the diameter of the mill screen.