Fractionation and exploitation of the component value of DDGS

DDGS成分价值的分离与开发

基本信息

批准号：
BB/J019445/1
负责人：
David Jonathan Leak
金额：
$ 45.43万
依托单位：
University of Bath
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2013
资助国家：
英国
起止时间：
2013 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FJ019445%2F1
关键词：
Fractionation exploitation component value DDGS

项目摘要

Some fermentation processes, eg brewing, use cereal starch as their source of carbohydrate. Typically, the residue of the cereal grain is not separated until the end of the fermentation process. In distilleries or in processes designed to produce alcohol for fuel, the liquid stream then goes through distillation which leaves a liquid residue ("thin stillage"). In large scale operations, the liquid and grain residues are dried to produce "distillers dried grain and solubles" (DDGS) which can be used as animal feed. In the UK, at least 2 large-scale wheat to alcohol plants will soon be operating. These will convert low-grade feed-wheat (of which the UK typically has a surplus) to alcohol for use as an automotive fuel, co-producing large quantities of DDGS, of a fairly consistent composition. The industrial members of IBTI have set a challenge of adding value to this DDGS, which this project addresses. Apart from the starch, cereal grain is composed mainly of protein, fibre and other non-starch carbohydrate and fats. The main animal feed value is contained in the protein, but the high fibre content means that DDGS is only useful for ruminant animals. In this project we intend to separate some of the protein, carbohydrate and fats and use them to produce higher value products, while still retaining the option to use the protein component as an animal feed, possibly for poultry. The latter is important as using DDGS as animal feed replaces imported soybean and thus, can reduce the greenhouse gas (GHG) emissions associated with soybean production and importation. Therefore, the challenge breaks down into 2 parts: 1) devising methods to remove the non-starch carbohydrate and fat from the DDGS without destroying the feed value, and 2) finding ways to gain added value from the extracted components. For the first part we have assembled a multidisciplinary team who are experts in addressing the engineering, biological and animal nutrition components of this project. From a process engineering perspective it would actually make sense to use the separated distiller's grain, before addition of the "solubles", as our starting material. This would be difficult to obtain, so we will recover the grain component from the DDGS. Removal of the fats could be done with an organic solvent, but this might leave undesirable residues in the animal feed. As an alternative we will investigate the use of super-critical carbon dioxide (SCCO2) extraction; a gentle, residue free method used for making decaffeinated coffee. The fibre and other carbohydrates will be removed mainly with enzymes, but we will need to find gentle physical pre-treatments (hot water or a short steam treatment) to facilitate enzyme access to the carbohydrates.In (2), we will focus on upgrading the carbohydrate and protein components. The carbohydrate could be used in a second fermentation process, if an organism was available that could convert the carbohydrates to useful products. To reduce the cost of this process we would need to find/create an organism that could use most of the carbohydrate polymers directly, rather than adding separate enzymes, so this part of the programme will focus on identifying suitable enzymes and the genes that encode them to put into established process organisms. Producing additional fuel or other chemicals by a secondary fermentation will not only improve the economics but also the GHG balance of the process. The proteins contained in wheat grain are rather specialised in their make-up, having a high frequency of certain amino acids. Availability in large volumes offers a unique opportunity to make specific chemicals, and the feasibility of exploiting this renewable chemicals approach will comprise a second strand of activity. If successful, this will also have a GHG benefit. Together with projected uses of the fatty fraction we will combine data from the whole exercise into an economic model for independent evaluation by potential users.

一些发酵过程，例如酿造，使用谷物淀粉作为碳水化合物的来源。通常，直到发酵过程结束才分离谷粒的残留物。在酿酒厂或设计用于生产燃料酒精的工艺中，液体流随后经过蒸馏，留下液体残留物（“稀釜馏物”）。在大规模生产中，液体和谷物残留物被干燥以生产“干酒糟和可溶物”(DDGS)，可用作动物饲料。在英国，至少有两家大型小麦制酒精工厂即将投入运营。这些将把低品位饲料小麦（英国通常有剩余）转化为酒精，用作汽车燃料，同时生产大量成分相当一致的 DDGS。 IBTI 的工业成员提出了一个挑战，即为 DDGS 增加价值，本项目正是解决这个问题。除淀粉外，谷物主要由蛋白质、纤维和其他非淀粉碳水化合物和脂肪组成。主要的动物饲料价值包含在蛋白质中，但高纤维含量意味着 DDGS 仅适用于反刍动物。在这个项目中，我们打算分离一些蛋白质、碳水化合物和脂肪，并用它们生产更高价值的产品，同时仍然保留使用蛋白质成分作为动物饲料（可能用于家禽）的选择。后者很重要，因为使用 DDGS 作为动物饲料替代进口大豆，因此可以减少与大豆生产和进口相关的温室气体 (GHG) 排放。因此，挑战分为两部分：1) 设计方法，在不破坏饲料价值的情况下从 DDGS 中去除非淀粉碳水化合物和脂肪，2) 找到从提取的成分中获得附加值的方法。对于第一部分，我们组建了一个多学科团队，他们是解决该项目的工程、生物和动物营养组成部分的专家。从工艺工程的角度来看，在添加“可溶物”之前使用分离的酒糟作为我们的起始材料实际上是有意义的。这很难获得，因此我们将从 DDGS 中回收谷物成分。可以使用有机溶剂去除脂肪，但这可能会在动物饲料中留下不良残留物。作为替代方案，我们将研究超临界二氧化碳 (SCCO2) 萃取的使用；用于制作脱咖啡因咖啡的温和、无残留的方法。纤维和其他碳水化合物主要通过酶去除，但我们需要找到温和的物理预处理（热水或短时间蒸汽处理）以促进酶接触碳水化合物。在（2）中，我们将重点关注升级碳水化合物和蛋白质成分。如果存在可以将碳水化合物转化为有用产品的生物体，则碳水化合物可以用于第二次发酵过程。为了降低这个过程的成本，我们需要找到/创造一种可以直接使用大部分碳水化合物聚合物的生物体，而不是添加单独的酶，因此该计划的这一部分将侧重于识别合适的酶和编码它们的基因放入已建立的过程有机体中。通过二次发酵生产额外的燃料或其他化学品不仅可以提高经济性，还可以提高该过程的温室气体平衡。小麦籽粒中所含的蛋白质的组成相当专业，某些氨基酸的含量很高。大量供应为制造特定化学品提供了独特的机会，而利用这种可再生化学品方法的可行性将构成第二部分活动。如果成功，这还将产生温室气体效益。连同脂肪分数的预计用途，我们将把整个练习的数据结合到一个经济模型中，供潜在用户进行独立评估。