贮存方式对水稻秸秆蒸爆处理前后饲用价值影响研究

发布时间：2018-12-17 01:17

【摘要】：中国以仅占世界7%的耕地养活占世界22%的人口,保障粮食安全一直是我国首要的任务。近年来,随着人们生活水平的提高,人们对肉、蛋、奶等食品的需求不断增长,带来了我国对牧草资源更多的需求,每年需要进口大量的饲料粮与牧草,甚至出现了人畜争粮和人畜争地的现象,粮食安全问题尤为突出。同时,农作物秸秆是一种重要的生物质资源,全世界年产约40亿吨,中国每年产出约8.2亿吨,其中有将近2.15亿吨被随意丢弃或焚烧,造成资源浪费和环境污染。如能将农作物秸秆制作成较为优质的饲料替代牧草供家畜食用,转化为人们日常所需的食品,不仅能够节约资源,保护环境,还能缓解粮食安全问题。秸秆替代牧草作为饲料由于其木质素含量高且木质素对纤维素有很强的包裹作用,致使虽然其总能值接近于干草,但是其可吸收的营养价值只相当于干草的一半。已有的研究结果表明,通过对秸秆的蒸爆处理可以有效降解秸秆的纤维成分,显著破坏木质素对纤维素的包裹作用,使反当动物对秸秆的采食量和消化吸收率都有明显地提高。本文在深入查阅国内外相关文献和李彬等人首次将蒸爆技术用于处理水稻秸秆饲料的研究基础上,以提高水稻秸秆酶解后还原糖产量为目标,对已有的蒸爆处理工艺进行了优化,把蒸爆的恒压保压过程设计为保压蒸煮和爆破前升压两个阶段,并分别进行控制,采用响应曲面分析法研究了保压蒸煮压力、保压蒸煮时间和爆破前压力3个因素对水稻秸秆酶解后还原糖产量的影响;将水稻秸秆按照露天贮存、棚舍贮存、一般青贮、半干青贮及氨化贮存5种不同的方式贮存,然后对水稻秸秆的各种贮存方式随贮存时间变化对其蒸爆前饲用价值的影响进行了研究;将水稻秸秆按照露天贮存、棚舍贮存、一般青贮、半干青贮及氨化贮存5种不同的方式贮存,然后对水稻秸秆的各种贮存方式随贮存时间变化对其蒸爆后饲用价值的影响进行了研究。主要研究结果如下:(1)水稻秸秆蒸爆处理工艺优化试验。保压蒸煮压力、保压蒸煮时间、爆破前压力对水稻秸秆酶解后还原糖产量的影响均显著。随着保压蒸煮压力和爆破前压力的增加,水稻秸秆酶解后还原糖产量明显提高;随着保压蒸煮时间的增加,水稻秸秆酶解后还原糖产量提高。在保证蒸爆处理后秸秆饲料的感官特性前提下,在保压蒸煮压力为1.6MPa、保压蒸煮时间为140s、爆破前压力为2.2MPa时,水稻秸秆酶解后还原糖产量最高,为37.48%,是原蒸爆工艺条件下的1.87倍。改进与优化后的蒸爆处理工艺能明显提高水稻秸秆酶解后还原糖产量。(2)贮存方式随贮存时间变化对水稻秸秆蒸爆前饲用价值的影响试验。从蒸爆前饲用价值看,水稻秸秆最佳的贮存方式为氨化贮存,其次为一般青贮,再次为半干青贮,然后是棚舍贮存,最后是露天贮存;同时水稻秸秆饲用价值变化主要发生在贮存前期。(3)贮存方式随贮存时间变化对水稻秸秆蒸爆后饲用价值的影响试验。从蒸爆后饲用价值看,水稻秸秆经一般青贮或者氨化贮存后再经蒸爆处理秸秆形态不再完整,近乎粉末状,已不再适合作为反刍动物的饲料;水稻秸秆半干青贮后再进行蒸爆处理,在常规营养成分、还原糖产量以及适口性方面均好于棚舍贮存,棚舍贮存好于露天贮存;水稻秸秆半干青贮后有助于强化蒸爆提高酶解后还原糖产量的效果。
[Abstract]:China, with only 7% of the world's arable land, provides for 22% of the world's population, and that food security is the primary task of our country. In recent years, with the improvement of people's living standard, the demand for food such as meat, eggs, milk and the like is increasing, which brings more demand for forage resources in China, The issue of food security is particularly acute. At the same time, the crop straw is an important biomass resource. The annual output of the crop straw is about 4 billion tons, and the output of China is about 800 million tons per year, of which nearly 2. 15 billion tons have been discarded or burned at will, resulting in resource waste and environmental pollution. for example, the crop straw can be made into higher-quality feed instead of the herbage for the domestic animal to eat, and the food can be converted into the food for people to daily use, so that the resource can be saved, the environment is protected, and the food security problem can be relieved. The straw is used as a feed, because the lignin content is high and the lignin has a strong wrapping effect on the cellulose, so that the straw can be absorbed by only half of the hay, although the total value of the straw is close to the hay. The results of the research show that the straw's fiber component can be effectively degraded by the steam explosion treatment of the straw, and the wrapping effect of the lignin on the cellulose is obviously destroyed, so that the feed intake and the digestion absorption rate of the straw are obviously improved. In this paper, on the basis of deep reference to the domestic and foreign literature and Li Bin's research on the treatment of rice straw feed for the first time, to improve the yield of reducing sugar after the enzymolysis of rice straw, the existing steam explosion treatment technology has been optimized. The constant-pressure water-retaining process of steaming and explosion was designed to be the two stages of pressure-saving cooking and pre-blasting step-up, and the control was carried out. The effect of pressure, pressure, cooking time and three factors of pre-blasting pressure on the yield of reducing sugar after the enzymolysis of rice straw was studied by the response surface analysis method. The rice straw was stored in open-air storage, shed storage, general ensilage, semi-dry ensilage and ammoniation storage in five different ways, and then the effects of various storage methods of rice straw on the value of pre-steaming and pre-explosion of rice straw were studied. The rice straw was stored in open-air storage, shed storage, general ensilage, semi-dry ensilage and ammoniation storage in five different ways, and then the effects of various storage methods of rice straw on the value of storage time of rice straw were studied. The main results are as follows: (1) The optimization test of rice straw steaming and explosion treatment process. The effect of pressure, pressure, cooking time and pre-blasting pressure on the yield of reducing sugar after the enzymolysis of rice straw was significant. With the increase of the pressure of the pressure and the pre-burst pressure, the yield of reducing sugar after the enzymatic hydrolysis of the rice straw is obviously improved, and the yield of the reducing sugar is improved after the enzymolysis of the rice straw with the increase of the time of the pressure-saving cooking. Under the premise of ensuring the sensory characteristics of the straw feed after the steaming and explosion treatment, the yield of the reducing sugar after the enzymolysis of the rice straw is the highest at the pressure of 1. 6MPa, the pressure and the cooking time of 140s, the pre-blast pressure is 2.2MPa, and the yield of the reducing sugar after the enzymolysis of the rice straw is 37. 48%, which is 1.87 times of that of the original steam explosion process. the improved and optimized steam explosion treatment process can obviously improve the yield of reducing sugar after the enzymolysis of the rice straw. (2) The effect of storage method with storage time on the value of rice straw pre-burst feeding. The best storage mode of rice straw is ammoniation storage, and the second is the general ensilage, which is the semi-dry ensilage, and then is stored in the shed, and finally is stored in the open air; at the same time, the change of the value of the rice straw feed mainly occurs in the storage period. (3) The effect of storage method on the value of rice straw steaming and explosion after steaming and explosion. the rice straw is no longer suitable for being used as a feed for ruminants after the rice straw is stored in general ensiling or ammoniated storage, and the rice straw is no longer suitable for being used as a feed for ruminants; after the rice straw is semi-dry ensilage, the steaming and explosion treatment is carried out, and in the conventional nutritional components, the yield and the palatability of the reducing sugar are good in the storage of the shed, and the shed is stored in the open air; and after the semi-dry silage of the rice straw, the effect of improving the yield of the reducing sugar after the enzymatic hydrolysis is enhanced.
【学位授予单位】：南京农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S816

【参考文献】