利用微生物及其产生的酶控制食品中丙烯酰胺的形成

丙烯酰胺是高温加工食品中一种常见的对人体有潜在危害的化学物质,其主要通过美拉德反应生成,但美拉德反应对改善食品色泽、风味等起到重要作用,因此如何有效抑制食品中丙烯酰胺的形成成为国内外研究热点。利用微生物对原料进行预处理具有抑制食品中丙烯酰胺形成的作用。文章简要介绍了食品中的丙烯酰胺以及微生物抑制丙烯酰胺形成的主要途径,重点阐述了微生物预处理在食品加工过程中抑制丙烯酰胺形成的研究,旨在为今后食品中丙烯酰胺的减控研究提供参考。     

油炸食品中丙烯酰胺的形成及减少措施

食品在加工过程中,特别是富含天门冬氨酸和还原糖的物质在高温(120℃以上)加工过程中会产生丙烯酰胺.试验表明,丙烯酰胺对动物有致癌性、神经毒性、生殖发育毒性的作用,但还没有足够的证据表明,食品加工过程中产生的丙烯酰胺对人体有致癌性.然而丙烯酰胺作为食品加工过程中产生的不受欢迎的物质,仍应尽量减少摄入.丙烯酰胺主要存在于油炸、高温烘焙的食品中,减少油炸食品中丙烯酰胺含量的途径主要有:减少或消除形成丙烯酰胺的前体物质;抑制加工过程丙烯酰胺的生成;破坏或使食物中形成的丙烯酰胺重新反应;在食品消费前将形成的丙烯酰胺去除.同时,改变以油炸和高脂肪食品为主的饮食习惯,尽量减少或防止丙烯酰胺可能对人体造成的伤害.     

热加工食品中丙烯酰胺的形成机理和风险分析

阐述了食品中丙烯酰胺产生的机理.丙烯酰胺是一种具有神经毒性的小分子化合物,它主要由游离的天门冬酰胺在食品加工过程中通过美拉德反应形成.天门冬酰胺和碳水化合物是形成丙烯酰胺必需的物质基础,高温(高于120 ℃)则是丙烯酰胺形成的关键条件,加工方式、水活度、pH值等因素也影响其形成.目前食品中丙烯酰胺的分析主要采用气相色谱-质谱法(GC-MS)与液相色谱-串联质谱联用技术(LC-MS/MS).作者对丙烯酰胺的分析方法进行了研讨并对丙烯酰胺的毒理学和食用含有丙烯酰胺食品的风险进行了讨论.     

食品中丙烯酰胺形成途径的研究进展

丙烯酰胺是一种有神经毒性和潜在致癌性的物质,2002年首次发现在高温油炸后的富含碳水化合物食品中存在,引起了世界各国研究者的广泛关注.综述了食品高温加工过程中丙烯酰胺形成的主要途径,天冬酰胺与还原糖发生Maillard(美拉德)反应.Strecker途径和N-糖苷途径是丙烯酰胺形成的主要途径;丙烯酸途径由于受自由氨的限制,虽然在食品中常见但生成丙烯酰胺的量比较少.     

丙烯酰胺毒性及油炸食品丙烯酰胺抑制方法研究进展

丙烯酰胺是富含碳水化合物和氨基酸的食品在高温加热下发生美拉德反应产生的,其对人体有一种潜在致癌作用.综述了丙烯酰胺的一些毒性,以及抑制油炸食品中丙烯酰胺产生的一些方法.     

食品中抑制丙烯酰胺的研究进展

丙烯酰胺是食品热加工中产生的一种潜在致癌物质,并且具有神经毒性、生殖毒性和遗传毒性,对人体健康危害较大。近年来有关丙烯酰胺的致癌机理、生成机理、分析方法和控制策略等方面都获得诸多研究成果,而对于抑制机理之间的关系,报导较少。本文基于丙烯酰胺的主要形成途径即食品原料中的天冬酰胺和还原糖通过高温加热条件反应生成丙烯酰胺的这一反应为基础,结合最新的文献研究,对丙烯酰胺的抑制作用机理和特定原理下的抑制剂进行系统概述,为将来寻找丙烯酰胺抑制剂和其作用机理研究提供理论参考。     

食品中丙烯酰胺的形成与风险分析

煎、炸、烤等高温处理是最普遍的食品加工方法,自瑞典的Trnqvist教授等首次在一些油炸和烧烤的淀粉类食品中发现具有毒性的丙烯酰胺以来,引发各国研究者高度关注,目前对丙烯酰胺在食品中的形成和分布仍没有一个统一的结论.对食品中丙烯酰胺的分布、形成及风险分析进行了综述.     

食品污染物丙烯酰胺毒性及其作用机制研究进展

食品中的丙烯酰胺（ACR）主要由富含淀粉的食物在高温下经美拉德反应形成,也可在低温发酵过程中产生。 丙烯酰胺可经 过消化道、呼吸道、皮肤等多种途径吸收,具有神经毒性、致癌作用、生殖毒、消化系统毒性、免疫毒性等多系统毒性作用。该文就丙烯 酰胺毒性及作用机制进行综述,旨在探讨丙烯酰胺毒性和可能机制,为食品污染物丙烯酰胺的安全风险控制提供参考。     

高温加热食品丙烯酰胺问题的探讨

丙烯酰胺对人和动物是一种有效累积性神经毒物，近年来研究发现在高温加热食品中有丙烯酰胺产生，本文介绍了高温加热食品中丙烯酰胺的形成机理、影响其形成的各种因素以及测定其含量的各种方法，最后提出了降低丙烯酰胺的一些措施．     

食品中丙烯酰胺的控制措施研究进展

该文阐述了食品中丙烯酰胺的毒性与控制方法。在食品加工过程中可以通过控制温度、加热时间、添加相关抑制剂等方法对丙烯酰胺加以控制。食物在油炸、烘焙等高温条件下容易产生丙烯酰胺,主要产生途径是美拉德反应,因此,食用薯条、面包等油炸、焙烤食品会摄入丙烯酰胺。丙烯酰胺具有神经毒性、生殖毒性、基因毒性、致癌性等,需要选择合适的方法控制其产生。     

油炸马铃薯片中丙烯酰胺形成的影响因素的研究

丙烯酰胺是富含碳水化合物和氨基酸的食品经高温加热发生美拉德反应而产生的,但有关影响丙烯酰胺形成因素的研究却较少。探讨了油炸温度、原料中还原糖和氨基酸含量、鲜薯切片浸泡液的柠檬酸浓度、油炸前薯片的水分含量及抗氧化剂和油的使用时间对丙烯酰胺形成的影响。结果表明:原料中还原糖和氨基酸含量越高,产品中生成的丙烯酰胺就越多;油炸温度越高,产品中丙烯酰胺含量也相应越高;浸泡液柠檬酸浓度越大,产品中丙烯酰胺含量越低;而随着半成品中含水量的降低,产品中的丙烯酰胺含量也逐渐减少;在油中添加不同浓度的BHT和TBHQ以及采用使用时间不同的油,对加工出来的薯片之间丙烯酰胺含量没有显著的影响。     

Role of mercaptans on acrylamide elimination

The reaction between acrylamide and mercaptans (benzyl mercaptan and N-acetylcysteine) was studied in an attempt to clarify some of the reaction pathways by which amino acids affect the acrylamide content in foods. The obtained results showed that, in the absence of oxygen, mercaptans reacted very rapidly with acrylamide producing the corresponding addition product. The activation energy of this reaction was 28–30 kJ/mol. The produced adduct was stable and only trace amounts of acrylamide were formed by thermal heating of 3-(benzylthio)propanamide. In the presence of oxygen, the addition product was not observed but a higher amount of acrylamide disappeared, more likely as a consequence of radical reactions. These last reactions could be inhibited by antioxidants, which prevented acrylamide losses. All these results constitute a new proof of the complexity of the reactions involved in the formation and elimination of acrylamide in foods, which are also going to depend on the food composition and the presence of oxygen. Potential toxicities of the compounds formed between acrylamide and mercaptans still remain to be analysed.     

Unravelling the kinetics of the formation of acrylamide in the Maillard reaction of fructose and asparagine by multiresponse modelling

A kinetic model for the formation of acrylamide in a fructose–asparagine reaction system at initial pH 5.5 is proposed, based on an approach called multiresponse kinetic modelling. The formation of acetic acid and formic acid from the degradation of fructose and its isomer glucose was included in the proposed kinetic model. The kinetic model suggests that the effect of temperature on acrylamide formation with fructose is more due to the preceding steps with the formation of the Schiff base. The use of fructose and lower pH resulted in a higher yield of acrylamide (3%), suggesting that both can play an important role in acrylamide mitigation. Furthermore, these models have shown that, at high temperatures (120–200 °C), the Maillard reaction rapidly goes into the advanced stages, forming high amounts of organic acids and high molecular weight melanoidins. Overall, these mechanistic models provide more insight of the formation of acrylamide in a quantitative way.     

Strecker aldehydes and α-keto acids,produced by carbonyl–amine reactions,contribute to the formation of acrylamide

The formation and disappearance of acrylamide in binary and ternary mixtures of asparagine (or acrylamide), carbonyl compounds and amino acid derivatives was studied in an attempt to understand the different reactions produced in mixtures of carbonyl compounds and amino acids. The carbonyl compounds assayed included glucose, 2,4-decadienal, mercaptopyruvic acid, phenylpyruvic acid, and phenylacetaldehyde. The assayed amino acids were cysteine, N-acetylcysteine, and phenylalanine, in addition to asparagine. All assayed carbonyl compounds were able to convert asparagine into acrylamide to various extents, and some of them were more reactive than glucose. In addition, they inhibited the Michael additions responsible for acrylamide disappearance. On the other hand, the addition of amino acids mostly resulted in decreases of acrylamide, although acrylamide also increased in some mixtures. Amino acids decreased acrylamide yield because of both their competence with asparagine for carbonyl compounds and their reaction with the produced acrylamide. However, carbonyl–amine reactions formed new carbonyl compounds, which increased acrylamide content. Therefore, asparagine degradation in the presence of amino acids is likely to be a balance between the decrease of degradation produced by the original carbonyl compounds and the increase of degradation due to the carbonyl compounds formed.     

焙烤食品中生成丙烯酰胺的影响因素

人类可能致癌物丙烯酰胺在富含碳水化合物的热加工食品中含量较高。本文结合近年来的研究结果.综合分析了影响焙烤食品中丙烯酰胺形成的因素(前体物质、水分、酸碱环境、油脂氧化、阳离子、抗氧化剂和加工工艺)。并探索将糠氨酸和羟甲基糠醛作为预洲焙烤食品中丙烯酰胺含量的指示物。     

Effect of flour type on Maillard reaction and acrylamide formation during toasting of bread crisp model systems and mitigation strategies

Maillard reaction along with caramelisation are the main chemical reactions occurring in bakery products. They are referred to as non enzymatic browning. In this work, the effect of flour type (wheat, rye and whole-wheat flours) and process conditions were investigated by using a bread crisp model system made up of flour, water and yeast. The bread was toasted at different temperature for different times. In a second set of experiments several additives (glycine, 0.1% on flour; asparaginase, 2000 U kg⁻¹ of flour and an antioxidant extract from green tea) were added to the basic formulations in order to test their ability in reducing the formation of potentially harmful Maillard reaction compounds such as HMF and acrylamide. Browning development and water content along with antioxidant activity were also monitored.Rye model systems produced more HMF and acrylamide at all temperature tested, while wholewheat systems produced less HMF, but more acrylamide than wheat one. The addition of glycine was effective in reducing acrylamide formation, and it increased browning development, antioxidant activity and HMF formation. Asparaginase reduced acrylamide formation up to 88% and had no effect on browning development and antioxidant activity. The addition of exogenous antioxidant compounds from green tea did not produce clear effect on acrylamide formation, thus it was not useful as mitigation strategy in bakery products, likely because of the low fat content.     

不同氨基酸和糖对美拉德反应产物的影响

利用半胱氨酸、甘氨酸、谷氨酸3 种氨基酸和木糖、葡萄糖2 种还原糖作为反应底物,模拟美拉德反应制备香精,并对其香气成分和有害物质进行综合分析。结果表明：参与反应的氨基酸种类越多,所测得的挥发性物质种数也越多,反应产物的风味越丰富;甘氨酸参与的美拉德反应中丙烯酰胺的生成量较少,而谷氨酸的参与反应中丙烯酰胺的生成量较多;还原糖种类对丙烯酰胺的产生影响不大;谷氨酸参与的美拉德反应产物中,5-羟甲基糠醛（5-hydroxymethylfurfural,5-HMF）含量高,而半胱氨酸和甘氨酸参与的反应产物中,5-HMF的含量较低;木糖可减少产物中的5-HMF的含量。利用本实验条件制备香精,产物中的丙烯酰胺和5-HMF含量在安全范围内。     

Effect of Steam Baking on Acrylamide Formation and Browning Kinetics of Cookies

Abstract: Effects of baking method and temperature on surface browning and acrylamide concentration of cookies were investigated. Cookies were baked in natural and forced convection and steam‐assisted hybrid ovens at 165, 180, and 195 °C and at different times. For all oven types, the acrlyamide concentration and surface color of cookies increased with increasing baking temperature. Significant correlation was observed between acrylamide formation and browning index, BI, which was calculated from Hunter L, a, and b color values, and it showed that the BI may be considered as a reliable indicator of acrylamide concentration in cookies. Acrylamide formation and browning index in cookies were considered as the first‐order reaction kinetics and the reaction rate constants, k, were in the range of 0.023 to 0.077 (min^?1) and 0.019 to 0.063 (min^?1), respectively. The effect of baking temperature on surface color and acrylamide concentration followed the Arrhenius type of equation, with activation energies for acrylamide concentration as 6.87 to 27.84 kJ/mol; for BI value as 19.54 to 35.36 kJ/mol, for all oven types. Steam‐assisted baking resulted in lower acrylamide concentration at 165 °C baking temperature and lower surface color for all temperatures. Steam‐assisted baking is recommended as a healthy way of cooking providing the reduction of harmful compounds such as acrylamide for bakery goods, at a minimal level, while keeping the physical quality. Practical Application: The kinetics of acrylamide formation and browning of cookies will possibly allow definition of optimum baking temperatures and times at convectional and steam‐assisted baking ovens. The kinetic model can be used by developing baking programs that can automatically control especially a new home‐scale steam‐assisted hybrid oven producing healthy products, for the use of domestic consumers.     

Acrylamide in Baking Products: A Review Article

Acrylamide or 2-propenamide is a chemical compound, with chemical formula CH₂=CH–CO–NH₂, that can be produced at high levels in high-carbohydrate heat-treated foods. The risks of acrylamide to health and its toxic properties (neurotoxicity, genotoxicity, carcinogenicity and reproductive toxicity) were demonstrated by the Scientific Committee on Toxicity, Ecotoxicity and the Environment in 2001. Potato and bakery products account for around 50% and 20% of human exposure to acrylamide, respectively. Factors affecting acrylamide formation and degradation in foods are acrylamide precursors such as free amino acids (mainly asparagine), reducing sugars and processing conditions (i.e. baking time and temperature, moisture content and matrix of product). The aim of this review was to present some results from recent investigations of the effects of different factors affecting acrylamide formation in bakery products. Finally, recommendations are proposed as guidelines for baking manufacturers to reduce the level of acrylamide in their products.