Axtell J D, Kirleis A W, Hassen M M, D'Croz Mason N, Mertz E T, Munck L
Proc Natl Acad Sci U S A. 1981 Mar;78(3):1333-5. doi: 10.1073/pnas.78.3.1333.
Published information indicates that rice, maize, and wheat proteins are much more digestible in children than sorghum proteins are (66-81% compared with 46%). However, this digestibility difference cannot be demonstrated with the weanling rat, which gave digestibility values of 80% for cooked and 85% for uncooked sorghum gruels. Therefore, a search was made for a laboratory system sensitive to the digestibility differences between sorghum and other cereals. We found that porcine pepsin in vitro shows these digestibility differences. Using pepsin, we have found that uncooked sorghum proteins have a high digestibility (78-100%), which drops to a range of 45-55% after cooking. Two fermented sheet-baked sorghum products (kisra and abrey) from Sudan gave pepsin digestibility values of 65-86%. In contrast, unfermented cooked gruels made in our laboratory from the same flours used for the kisra and abrey gave pepsin values of only 44-56%. Therefore, fermentation improves pepsin digestibility of sorghum. The digestibility values of other sorghum-based foods prepared in the semiarid tropics need surveying. Those with high pepsin digestibility values hopefully should be more digestible (in children) than are the cooked sorghum gruels studied to date by human nutritionists.
已发表的信息表明，大米、玉米和小麦蛋白在儿童体内的消化率比高粱蛋白高得多（分别为66 - 81%，而高粱蛋白为46%）。然而，这种消化率差异在断奶大鼠身上无法体现，断奶大鼠对煮熟高粱糊的消化率为80%，对未煮熟高粱糊的消化率为85%。因此，人们开始寻找一种对高粱和其他谷物消化率差异敏感的实验室系统。我们发现猪胃蛋白酶在体外能显示出这些消化率差异。使用胃蛋白酶，我们发现未煮熟的高粱蛋白具有较高的消化率（78 - 100%），但煮熟后消化率会降至45 - 55%。来自苏丹的两种发酵薄烤高粱制品（kisra和abrey）的胃蛋白酶消化率为65 - 86%。相比之下，我们实验室用制作kisra和abrey的相同面粉制作的未发酵熟糊的胃蛋白酶消化率仅为44 - 56%。因此，发酵可提高高粱的胃蛋白酶消化率。半干旱热带地区制备的其他高粱类食品的消化率值有待调查。那些胃蛋白酶消化率值高的食品有望比人类营养学家迄今研究的煮熟高粱糊（在儿童体内）更易消化。
