Genetic improvement of wheat to reduce the potential for acrylamide formation during processing.

对小麦进行遗传改良，以减少加工过程中丙烯酰胺形成的可能性。

• 批准号: BB/I020942/1
• 负责人: Simon Griffiths
• 金额: $ 12.34万
• 依托单位: John Innes Centre
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FI020942%2F1
• 关键词: Genetic; improvement; wheat; reduce; potential

The formation of the chemical contaminant, acrylamide, during high-temperature cooking and processing of wheat, rye, potato and other mainly plant-derived raw materials was reported in 2002, and the presence of acrylamide in foods is now recognized as a difficult problem for the agricultural and food industries. Acrylamide causes cancer in laboratory animals and is therefore considered to be probably cancer-causing in humans. It also affects the nervous system and reproduction. Cereals, of which wheat is the most important, generate half of the acrylamide in the European diet, with biscuits, snacks and breakfast cereals being of particular concern. The FAO/WHO Expert Committee on Food Additives has recommended that dietary exposure to acrylamide should be reduced and the European Commission is expected to issue guidance values on acrylamide levels in food before the end of 2010. The current draft of the guidance values proposes levels that will not be consistently achievable for many products. The proposed guidance level for breakfast cereals, for example, is 400 parts per billion (ppb), while levels in some wheat-based breakfast cereals are over 1000 ppb. Furthermore, many Member States support these guidance values becoming regulatory limits. The food industry therefore requires both short-term solutions and a long-term programme of reduction in the acrylamide forming potential of wheat in order to comply with this regulatory situation as it evolves. Methods for reducing acrylamide formation during processing have proven to be difficult to apply to wheat products, either being ineffective or having an unacceptably adverse effect on product quality. The development of commercially viable wheat varieties that are low in acrylamide-forming potential but retain grain characteristics that are important for end product quality would help to address, at source, the problem of acrylamide formation in food manufacture, catering and home cooking, without the need for additives or potentially costly changes to processes. The high-temperature degradation of an amino acid, asparagine, in the presence of sugars (glucose, fructose and maltose) has been shown to be the major route for acrylamide formation and the limiting factor in wheat products is free asparagine. Wheat contains significantly higher levels of asparagine than most other grains. Furthermore, whole wheat grain and wheat bran, which have important health promoting properties, tend also to have higher asparagine levels than refined wheat flour. This project seeks to identify currently available varieties and genotypes of wheat that are low in asparagine and provide wheat breeders with the genetic tools to reduce the concentration of asparagine further. This application is being submitted through the BBSRC's stand-alone LINK scheme. The project will benefit from the involvement of a major European/GB wheat breeder and a consortium of wheat supply chain businesses, allowing for the identification and review of key targets by the industrial partners. The level of industry support is indicative of the importance of the acrylamide issue to wheat supply chain businesses and the potential impact of the project. A letter of support has also been provided by the Food Standards Agency. The project will use state-of-the-art techniques for analysing amino acid concentrations in wheat flour, exploit the genetic resources in wheat that have been developed at Rothamsted and the John Innes Centre, including mapping populations, wheat genetic modification (as a research tool) and high-throughput screening of mutant populations, and utilise the latest DNA sequencing techniques to study differences in gene expression between high and low asparagine genotypes. The impact of reductions in acrylamide-forming potential of grain on performance in industrial processes will be assessed by food industry partners.

2002年有报道称，小麦、黑麦、马铃薯和其他主要植物来源的原材料在高温蒸煮和加工过程中会形成化学污染物丙烯酰胺，食品中丙烯酰胺的存在现已被认为是农业和食品工业的一个难题。丙烯酰胺会导致实验动物癌症，因此被认为可能导致人类癌症。它还影响神经系统和生殖系统。谷物（其中以小麦最为重要）产生了欧洲饮食中一半的丙烯酰胺，其中饼干、零食和早餐谷物尤其令人担忧。粮农组织/世界卫生组织食品添加剂专家委员会建议应减少膳食中丙烯酰胺的摄入量，欧盟委员会预计将在 2010 年底前发布食品中丙烯酰胺含量的指导值。目前的指导值草案提出的水平对于许多产品来说无法始终达到。例如，建议的早餐谷物指导水平为十亿分之 400 (ppb)，而某些以小麦为主的早餐谷物中的水平超过 1000 ppb。此外，许多成员国支持这些指导值成为监管限制。因此，食品工业既需要短期解决方案，又需要制定减少小麦丙烯酰胺形成潜力的长期计划，以便适应不断发展的监管形势。事实证明，减少加工过程中丙烯酰胺形成的方法很难应用于小麦产品，要么无效，要么对产品质量产生不可接受的不利影响。开发商业上可行的小麦品种，其丙烯酰胺形成潜力较低，但保留对最终产品质量重要的谷物特性，将有助于从源头解决食品制造、餐饮和家庭烹饪中丙烯酰胺形成的问题，而无需添加剂或可能代价高昂的工艺改变。氨基酸天冬酰胺在糖（葡萄糖、果糖和麦芽糖）存在下的高温降解已被证明是丙烯酰胺形成的主要途径，而小麦产品中的限制因素是游离天冬酰胺。小麦的天冬酰胺含量明显高于大多数其他谷物。此外，具有重要健康促进特性的全麦谷物和麦麸也往往比精制小麦粉含有更高的天冬酰胺含量。该项目旨在确定目前可用的天冬酰胺含量低的小麦品种和基因型，并为小麦育种者提供进一步降低天冬酰胺浓度的遗传工具。该申请是通过 BBSRC 的独立 LINK 方案提交的。该项目将受益于欧洲/英国主要小麦育种商和小麦供应链企业联盟的参与，从而使工业合作伙伴能够确定和审查关键目标。行业支持水平表明丙烯酰胺问题对小麦供应链业务的重要性以及该项目的潜在影响。食品标准局还提供了一封支持信。该项目将使用最先进的技术分析小麦面粉中的氨基酸浓度，利用洛桑和约翰英尼斯中心开发的小麦遗传资源，包括绘制群体图谱、小麦基因改造（作为研究工具）和突变群体的高通量筛选，并利用最新的DNA测序技术来研究高天冬酰胺和低天冬酰胺之间基因表达的差异 基因型。食品行业合作伙伴将评估谷物中丙烯酰胺形成潜力的降低对工业流程性能的影响。