牛干巴热加工中丙烯酰胺形成的分子机理及其阻控研究

Acrylamide (AA) has a neurotoxicity, reproductive toxicity and potential carcinogenicity, which is widely found in heat-treated foods. we found the higher levels of acrylamide in heat-treated cured beef of the Hui nationality, which will harmful to human health. The formation molecular mechanism of acrylamide in the heat-treated process of cured beef is not clear. This project will apply metabolomics method, and use cured beef as the object. By using GC-MS, LC-TOF-MS/MS, NMR combined with correlation analysis and stable isotope tracing, the AA and precursors of the cured beef before and after thermal treatment will be analyzed. The qualitative and quantitative relationship between the AA and its precursors and the metabolic pathway of precursor transformation into AA will be elucidated. Then, The effects of precursors and processing conditions on AA and its key intermediates were studied by stoichiometry and kinetic model, which will elucidate the rules of AA generation and influencing factors in different reaction conditions were elucidated. The methods of inhibiting the formation of AA and the blocking of key sites were explored from the metabolic pathway using LC-TOF-MS/MS and kinetic model. This project will reveal the dynamic changes of precursor and the influencing factors, get the molecular mechanism of AA, explain the mechanism of AA resistance, and which will provide the theoretical basis and scientific foundation to control the AA formation in heat-treated cured beef, and also provide new scientific ideas for the AA traceability and control mechanism in other heat-treated foods.

丙烯酰胺（AA）具有神经毒性、生殖毒性和潜在致癌性，其广泛存在于热加工食品中。前期发现回族牛干巴热加工过程中产生较高的AA，存在安全隐患，但目前对其形成机理的研究仍是空白。本项目应用代谢组学，利用GC-MS、LC-TOF-MS/MS、NMR结合相关性检验初判、同位素示踪复判等方法追踪牛干巴热加工前后AA及其中间体，明确AA前体物质的质与量及生成顺序，阐明前体转化为AA的代谢途径。采用化学计量学及动力学模型，研究前体和加工条件对AA及其关键中间体的影响，阐明模拟体系中不同反应条件下AA生成的规律及其影响因素。利用LC-TOF-MS/MS结合动力学模型从代谢途径上探索抑制AA形成的方法和阻断关键位点。通过研究探明AA前体物质动态变化规律及影响因素，揭示AA形成分子机理，阐释AA阻控机制。为牛干巴热加工制品安全控制提供理论基础和科学依据，为其它食品中AA的溯源及阻控机制的诠释提供新的科研思路。

丙烯酰胺是食品热加工过程中的典型危害物，对人体有致畸、神经毒性和潜在致癌性。牛干巴是云南省特有的回族传统腌腊牛肉制品，高温油炸牛干巴热加工过程中易产生较高的丙烯酰胺，存在安全隐患，探明油炸牛干巴中丙烯酰胺前体物质动态变化规律及影响因素，揭示AA形成分子机理，阐释AA阻控机制。为有效抑制牛干巴热加工中丙烯酰胺的形成提供了科学依据，为研究其他热加工食品中有害物产生机理提供了新的视角和理论基础。本项目样品前处理（组分的提取、富集、净化、分离）基础上，建立了一种采用HPLC-Q-TOF-MS/MS测定油炸牛干巴食品中丙烯酰胺的方法，该方法的检出限为3.51μg /kg，回收率为89.8%-97.5%，相对标准偏差RSD为0.11%-0.59%，该法可用于油炸肉制品中丙烯酰胺含量的检测。其次，研究了不同煎炸油类型、煎炸温度、煎炸时间、煎炸油品质等对油炸牛干巴基本成分和丙烯酰胺的动态变化规律。通过统计分析确定了影响牛干巴油炸过程中形成的第一主成分为羰基价和油炸温度，第二主成分为油的使用频率、水分和还原糖，第三主成分为油炸时间、蛋白质和游离氨基酸的含量。系统地研究了牛干巴在油炸热处理过程中以丙烯醛、丙烯酸为标志性物质的丙烯酰胺生成途径，揭示了丙烯酰胺的分子形成机理。研究天冬酰胺和丙烯酸模拟反应体系在油炸过程中丙烯酰胺随油脂类型、油炸参数的变化规律，阐释了外部添加体系对丙烯酰胺的抑制和阻断规律，最后根据丙烯酰胺形成机理，通过原料预处理、热加工条件与丙烯酰胺形成之间的相关性，建立了阻断丙烯酰胺形成的有效方法。