Russell R W, Lolley J R
Department of Animal and Dairy Sciences, Auburn University, AL 36849.
J Dairy Sci. 1989 Sep;72(9):2427-30. doi: 10.3168/jds.S0022-0302(89)79377-2.
Experiments were conducted to determine the effectiveness of urea in deactivating tannin in high tannin milo. High tannin milo (Pioneer B 815, 3.4 +/- .3% tannin) was reconstituted with aqueous urea solutions to give combinations of 26, 30, and 34% moisture with 2, 3, and 4% urea (percentage of urea per dry weight of milo). All treatments were maintained at 25 degrees C and were effective in deactivating tannin with no differences among moisture or urea content. The average rate of tannin deactivation was 68 +/- 2% d-1. Temperature affected rate of tannin deactivation in milo reconstituted to 30% moisture and 3% urea when stored at 25 or 60 degrees C. Rate of tannin deactivation was 44 +/- 5 and 89 +/- 18% d-1 at 25 and 60 degrees C, respectively. Tannin in high tannin milo can be deactivated rapidly and completely by reconstitution with aqueous urea. These studies demonstrate that tannin is deactivated completely under conditions where urea is an effective preservative of high moisture milo.
开展实验以确定尿素对高单宁含量的高粱中丹宁酸的钝化效果。将高单宁含量的高粱（先锋B 815，单宁含量为3.4±0.3%）用尿素水溶液复配，得到水分含量分别为26%、30%和34%且尿素含量分别为2%、3%和4%（基于高粱干重的尿素百分比）的组合。所有处理均保持在25℃，在钝化丹宁酸方面均有效，水分或尿素含量之间无差异。丹宁酸钝化的平均速率为68±2% d⁻¹。当复配至水分含量为30%且尿素含量为3%的高粱在25℃或60℃储存时，温度影响丹宁酸的钝化速率。在25℃和60℃时，丹宁酸的钝化速率分别为44±5% d⁻¹和89±18% d⁻¹。通过用尿素水溶液复配，高单宁含量高粱中的丹宁酸可被迅速且完全地钝化。这些研究表明，在尿素是高水分含量高粱有效防腐剂的条件下，丹宁酸可被完全钝化。
