美拉德反应产物生物活性及衍生危害物安全控制研究进展

美拉德反应(Maillard reaction,MR)是食品在加热过程中氨基化合物与羰基化合物之间的反应,该过程可导致食品褐变,风味物质、活性成分和衍生危害物的形成。美拉德反应产物(Maillard reaction products,MRPs)具有多种生物活性成分如类黑精、还原酮等。当反应控制不当时,可产生一些危害衍生物如丙烯酰胺、杂环胺类、晚期糖基化末端终产物(Advanced glycation end products,AGEs)等物质,可引起癌症及慢性疾病的发生(人体动脉粥样硬化、视网膜病变、神经衰退性疾病及糖尿病等)。因而本文综述了美拉德反应产物的生物活性,同时也探讨了常见的美拉德反应危害衍生物的生成机制及有效抑制方法,以期为探索合理利用美拉德反应、充分发挥其生物活性作用及减少不利影响的方法提供指导意义。     

Interaction of lipid in the maillard reaction between cysteine and ribose: The effect of a triglyceride and three phospholipids on the volatile products

The inclusion of phospholipid in the Maillard reaction between cysteine and ribose is known to modify the volatile aroma compounds produced. The contributions made to the headspace volatiles by 60 major products of this reaction have been compared for four different lipids and their effect on aroma quality noted. The results described demonstrate marked dissimilarities between the behaviour of the four lipids. The most noticeable distinction was between the effect of triglyceride and the three phospholipids, but there were also variations in the way that each of the three phospholipids participated in the Maillard reaction. As well as displaying marked differences in volatile products, reaction mixtures containing the four lipids possessed distinct aroma characteristics; the phospholipids containing phosphatidylethanolamine conferred the most meat-like odour. These differences appear to be caused by the dissimilar fatty acid compositions and polar moieties. Thus this study underlines the importance of lipid interaction in the Maillard reaction for the formation of flavour.     

Amino Acid Degradations Produced by Lipid Oxidation Products

Differently to amino acid degradations produced by carbohydrate-derived reactive carbonyls, amino acid degradations produced by lipid oxidation products are lesser known in spite of being lipid oxidation a major source of reactive carbonyls in food. This article analyzes the conversion of amino acids into Strecker aldehydes, α-keto acids, and amines produced by lipid-derived free radicals and carbonyl compounds, as well as the role of lipid oxidation products on the reactions suffered by these compounds: the formation of Strecker aldehydes and other aldehydes from α-keto acids; the formation of Strecker aldehydes and olefins from amines; the formation of shorter aldehydes from Strecker aldehydes; and the addition reactions suffered by the olefins produced from the amines. The relationships among all these reactions and the effect of reaction conditions on them are discussed. This knowledge should contribute to better control food processing in order to favor the formation of desirable beneficial compounds and to inhibit the production of compounds with deleterious properties.     

磷脂降解对食品风味影响的研究进展

磷脂是肉制品或水产品风味物质重要的前体物质,其降解产物对食品风味有着重要贡献.磷脂中的不饱和脂肪酸含量高,相比其他脂质更能促进食品的氧化降解,此外磷脂氧化降解与美拉德反应的相互作用也对食品的风味形成有重要影响.随着技术和研究方法的不断改进,磷脂组学的研究方法也得以快速发展.文章对磷脂的水解、氧化过程及其降解产物对食品风...     

NMR和GC-MS研究加热对奶油主要成分及香气化合物的影响

为深入了解加热过程中奶油主要成分和香气成分的变化机理，对加热前后奶油进行分析。利用核磁共振（nuclear magnetic resonance，NMR）技术分别对奶油中的极性组分和非极性组分进行定量分析，同时利用气相色谱-质谱（gas chromatography-mass spectrometry，GC-MS）联用技术对加热前后奶油中的关键香气化合物进行鉴定。NMR分析表明，奶油中的极性组分主要为乳糖以及少量的游离氨基酸、游离脂肪酸和有机酸，非极性组分主要为甘油三酯以及少量的双甘酯和单甘酯。经加热后，极性组分含量大量减少，主要为乳糖和游离氨基酸，而非极性组分含量减少相对较小；GC-MS分析表明，短链脂肪酸和醛类含量增加相对较少，甲基酮、内酯和美拉德反应产物含量增加显著，其中甲硫基丙醛、麦芽酚和呋喃酮仅在加热后奶油中检出。结果表明加热过程中美拉德反应产物的形成和脂质来源化合物的增加分别造成了奶油中极性组分和脂肪酸的减少。该研究结果为奶油风味及产品研究提供了思路。     

Coordinate contribution of lipid oxidation and Maillard reaction to the nonenzymatic food browning

Lipid oxidation and the Maillard reaction are probably the two most important reactions in Food Science. Both include a whole network of different reactions in which an extraordinary complex mixture of compounds are obtained in very different amounts and produce important changes in food flavor, color, texture, and nutritional value, with positive and negative consequences. This article analyzes the interactions between both reactions, with special emphasis in nonenzymatic browning development, by discussing the influence of lipid oxidation products in the Maillard pathway and vice versa, as well as the existence of common intermediates and polymerization mechanisms in both reactions. The existing data suggest that both reactions are so interrelated that they should be considered simultaneously to understand the products of the Maillard reaction in the presence of lipids and vice versa, and should be included in one general pathway that can be initiated by both lipids and carbohydrates.     

美拉德反应产物对肠道微生物影响的研究进展

美拉德(Maillard)反应是食品加工、贮藏及烹饪过程中普遍存在的重要反应。Maillard反应会导致蛋白质或氨基酸的胃肠消化性下降,进而增加其进入大肠被肠道微生物发酵利用的可能性。本文主要综述Maillard反应产物对肠道微生物生长及其发酵代谢产物形成等影响的研究进展,旨在为研究Maillard反应产物、肠道微生物与健康的关系提供参考。     

不同分子质量大豆蛋白和鸡肉酶解物的美拉德反应产物风味特征分析

为了研究不同分子质量的肽在美拉德反应后的风味特征,以大豆蛋白和鸡肉为原料酶解得到蛋白酶解物。对酶解物超滤分离得到小于1000Da、1000~5000Da和大于5000Da的不同分子质量肽组分,并对大豆蛋白和鸡肉酶解物完全酸水解得到复合氨基酸。在得到的肽段和氨基酸中添加一定量的木糖,构建美拉德反应模型。对美拉德反应产物感官特性进行评价,再采用气相色谱-质谱联用、高效液相色谱对挥发性和不挥发性化合物进行分析。结果表明:在2种不同蛋白来源的酶解物的美拉德反应产物中,共鉴定出挥发性化合物69种,其中吡嗪和呋喃硫醇等肉香味化合物的含量最高。统计分析表明:不同分子质量的肽和游离氨基酸的挥发性化合物存在明显差异。小于1000Da的肽在美拉德反应过程促进了吡嗪类化合物的生成,其中包括了吡嗪、5-甲基-2-乙基吡嗪、2,5-二甲基-3-乙基吡嗪、三甲基吡嗪、2-乙酰基吡咯等挥发性化合物。与肽相比,游离氨基酸有利于含硫化合物如呋喃硫醇类和噻吩类物质的生成。有29种挥发性化合物的相对气味活性值大于1。偏最小二乘回归研究了气味化合物与感官评价之间的相关性,发现小于1000Da的肽与基本的肉味和浓厚味密切相关,而大于5000Da的肽与苦味和焦煳味密切相关。在美拉德反应后,分子质量大于5000Da的肽数量显著减少；分子质量1000~5000Da的肽降解可以补充消耗的游离氨基酸；分子质量小于1000Da的肽容易发生交联和聚合现象而含量增加,其产物对风味的影响明显增强,能更好地体现基本的肉味、鲜味和浓厚味。希望研究可以为利用蛋白质酶解物生产美拉德反应产物的应用提供理论支撑和指导。     

Comparison of volatile Maillard reaction products from tagatose and other reducing sugars with amino acids

In this study, in order to investigate the effects of tagatose on the Maillard reaction, volatile Maillard reaction products (V-MRPs) produced from aqueous model systems containing various reducing sugars (glucose, galactose, fructose, and tagatose) and amino acids (glycine, valine, leucine, asparagine, and cysteine) were analyzed and then compared. Furans, furan derivatives, pyrazines, and some sulfur-containing heterocyclic compounds, such as thiazoles, thiophenes, and thiols, were mainly identified. The amounts of furans and furan derivatives were higher in the model systems of ketoses (fructose or tagatose) with amino acids than those of aldoses (glucose or galactose) with amino acids. In particular, 2-acetylfuran was detected 2-20 times more in the V-MRPs of tagatose as compared to those produced from the other reducing sugars. Also, 2-acetylpyrrole, one of nitrogen-containing heterocyclic compounds, was more abundant from the thermal reactions of tagatose-glycine and tagatose-valine compared to those of other reducing sugars-amino acids. More 2-acetylthiazole and thiophenes were found in tagatose-cysteine model system than in those of glucose with cysteine.     

Study on the flavor contribution of phospholipids and triglycerides to pork

For investigating the flavor contribution of phospholipids and triglycerides to pork, the longissimus muscle of Rongchang (RC) and PIC (bred by PIC Company of England) pig were selectively removed of intramuscular triglycerides or total intramuscular lipids. After cooking, the flavor of different samples was compared by sensory evaluation, gas chromatographymass spectrometry (GC-MS), and electronic nose. The results showed that removing triglycerides had little effect on the aroma of the cooked meat, but when total intramuscular lipids were removed a remarkable difference was observed. The control samples covaried strongly with some lipid-derived products, and the petroleum ether defatted samples also positively related to these compounds, but to a lesser extent, both of them negatively covaried with chloroform-methanol extracted samples which associated with some Maillard reaction products. Moreover the flavor difference between 2 breeds would decrease when triglycerides were removed, and reduce further when phospholipids and triglycerides were removed simultaneously. These results suggested that intramuscular lipids especially phospholipids contributed significantly to pork flavor, the flavor difference between 2 breeds resulted mainly from different intramuscular lipids content and composition.     

Free radical-scavenging activity of nonenzymatically-browned phospholipids produced in the reaction between phosphatidylethanolamine and ribose in hydrophobic media

The reaction of phosphatidylethanolamine (PE) and ribose (RI) in olive oil was studied in an attempt to both explore the possibilities of producing Maillard reaction in hydrophobic media and analyse the antioxidant properties of the formed compounds. When oil samples containing PE/RI mixtures were heated at a temperature higher than 90 °C, the oil rapidly developed browning, fluorescence, and free radical-scavenging activity, which was higher than the developed by the oil in the absence of added compounds or in the presence of only either PE or RI. These changes were a consequence of the formation of Maillard reaction products in the oil by reaction between PE and RI. Among them, the N-alkylpyrrole derivatives produced in this reaction could be determined by GC–MS after transpyrrolisation. Differently to Maillard products formed between carbohydrates and amino acids, the products of the reaction with aminophospholipids are more hydrophobic and, therefore, better candidates to be employed as lipophilic antioxidants in food products. Because of the different polarity of Maillard products between carbohydrates and either amino acids or aminophospholipids, Maillard reaction can be a useful procedure to obtain a wide range of antioxidants with different polarities to be employed in different food systems.     

茶叶加工中美拉德反应对品质形成与安全的影响分析

美拉德反应主要是氨基化合物和羰基化合物之间发生的非酶促反应,广泛存在于热加工食品中。茶叶是重要的农产食品,在加工过程中美拉德反应对其香气、色泽、滋味品质的形成都具有重要作用。同时,随着美拉德反应在食品加工中研究的深入,其产物的功能性与安全性越来越受人们的关注。基于此,本文重点从美拉德反应对茶叶香气、色泽、滋味形成及安全性等方面进行综述分析,为探索茶叶加工中合理利用美拉德反应,充分发挥其功能作用而减少其不利影响提供参考意义。     

Flavour formation in meat and meat products: a review

The characteristic flavour of cooked meat derives from thermally induced reactions occurring during heating, principally the Maillard reaction and the degradation of lipid. Both types of reaction involve complex reaction pathways leading to a wide range of products, which account for the large number of volatile compounds found in cooked meat. Heterocyclic compounds, especially those containing sulfur, are important flavour compounds produced in the Maillard reaction providing savoury, meaty, roast and boiled flavours. Lipid degradation provides compounds which give fatty aromas to cooked meat and compounds which determine some of the aroma differences between meats from different species. Compounds formed during the Maillard reaction may also react with other components of meat, adding to the complexity of the profile of aroma compounds. For example, aldehydes and other carbonyls formed during lipid oxidation have been shown to react readily with Maillard intermediates. Such interactions give rise to additional aroma compounds, but they also modify the overall profile of compounds contributing to meat flavour. In particular, such interactions may control the formation of sulfur compounds, and other Maillard-derived volatiles, at levels which give the optimum cooked meat flavour characteristics.     

油炸肉制品风味的研究进展

油炸风味的产生是油炸肉制品流行的一个重要原因。与其他传统的热加工方式相比,油炸处理的传热传质机制较为复杂,并且挥发性化合物种类丰富（如醛、醇、酮、碳氢化合物、呋喃、吡嗪等）,形成特有的油炸风味,对消费者有较强的吸引力。该研究通过综合文献研究,对脂肪氧化、美拉德反应以及两种反应产物之间的相互作用产生的油炸风味进行了论述,着重讨论了脂肪氧化和美拉德反应的形成途径和在油炸过程中挥发性化合物的形成,以及影响因素。除此之外,关注到油炸过程中形成的有害成分以及不良风味物质,例如杂环胺、多环芳烃等的形成及其控制措施。总体而言,充分了解油炸挥发物的化学来源,优化油炸风味以及开发不同的油炸方式来提高消费者对油炸肉制品的接受度以及提高食品质量和安全性具有重要意义。     

美拉德反应对金枪鱼红肉酶解液挥发性物质和游离氨基酸的影响

为了高值化利用金枪鱼红肉这一蛋白质资源,利用气相色谱-质谱联用(GC-MS)和高效液相色谱(HPLC),研究美拉德反应对金枪鱼红肉酶解液挥发性物质和游离氨基酸的影响。GC-MS结果表明,金枪鱼红肉酶解液中共检测出19种挥发性化合物,其中未加热的酶解液中有10种,而经过不同时间(30、60和90 min)加热的酶解液中,分别检测出12种、15种和15种,其中呋喃类物质的含量随反应时间延长显著增加。HPLC分析表明,随着加热时间的增加,酶解液中呈味氨基酸总量均上升,但是鲜味和甜味氨基酸的比例呈下降趋势,苦味氨基酸则呈上升趋势。表明,美拉德反应赋予酶解液更加丰富的风味的同时,却使其呈现更多的苦味。     

Impact of phloretin and phloridzin on the formation of Maillard reaction products in aqueous models composed of glucose and L-lysine or its derivatives

In the present study, the effects of phloretin and phloridzin on the formation of Maillard reaction products in a lysine-glucose model with different reactant ratios were systematically investigated. In terms of the formation of Maillard-type volatiles, phloretin and phloridzin treatmen could significantly reduce their generation, where the effects depend on the ratio of lysine to glucose used in the model systems. Phloretin and phloridzin could also affect the colour development of Maillard reactions; especially phloretin, which could significantly promote the formation of brown products in the system with the lowest ratio of lysine to glucose. Based on the carbon module labelling (CAMOLA) technique and HPLC-DAD-ESI/MS analysis, it was found that phloretin and phloridzin could actively participate in the Maillard reaction and directly react with different reactive carbonyl species. The effect of phloretin and phloridzin treatment in both N(α)-acetyllysine-glucose (AC-glu), and N-acetyl-gly-lys methyl ester acetate salt-glucose (AG-glu) model systems, which are close to the Maillard reactions occurring in real food, where the free amino groups of lysine residues were considered as the reactive site, were further investigated. Similar impacts on the formation of Maillard-type volatiles and brown products as in the lysine-glucose models were observed which can also be explained by the capability of phloretin and phloridzin to quench sugar fragments formed in these model reactions.     

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。     

鸡肉酶解物中不同氨基前体对肉香味形成的贡献

通过超滤分离鸡肉酶解物,制备分子质量小于1 ku、1~5 ku、大于5 ku的3个肽组分样品。采用盐酸水解鸡肉酶解物,制备氨基酸组分样品。以3个肽组分和氨基酸组分及葡萄糖为原料,设计加或不加氧化鸡脂两类共8个模型反应体系,研究鸡肉酶解物中不同氨基组分对肉香味形成的贡献。通过分析比较反应产物在波长420 nm处紫外-可见光吸收值和pH变化值,以及固相微萃取/气-质联机分析挥发性风味物质组成,发现对于加与不加氧化鸡脂的两类反应体系,均为随氨基组分的分子质量增大,420 nm处紫外-可见光吸收值降低,产生的挥发性化合物总量减少,这可能因分子质量大反应活性差导致。无论加或不加氧化鸡脂,均为氨基酸组分对含硫化合物贡献最大,小于1 ku和1~5 ku肽组分对吡嗪类化合物贡献最大。但氧化鸡脂中含有羰基类脂质氧化产物可对美拉德反应有影响,与不加氧化鸡脂相比,加入氧化鸡脂后420 nm处紫外-可见光吸收值稍增加,产生的风味化合物总量大幅度下降,并有带烷基链的化合物(如2-甲基-5-丙基-噻吩)含量增加及新杂环化合物2-丁基吡啶出现。     

氨基酸对浓香葵花籽油美拉德反应风味的贡献

通过研究比较脱脂葵花籽粕烘烤前后的氨基酸组成及风味变化,建立了以浸出一级葵花籽油为基质的氨基酸与葡萄糖美拉德反应风味模拟模型,比较分析了12种氨基酸与葡萄糖美拉德反应风味模拟模型体系中形成的挥发性化合物与浓香葵花籽油风味化合物的异同。结果表明:赖氨酸、精氨酸、组氨酸对浓香葵花籽油美拉德反应风味的贡献最大,是浓香葵花籽油美拉德反应风味形成的主要前体物质。赖氨酸、精氨酸、组氨酸3组模型体系中美拉德反应挥发性化合物与浓香葵花籽油风味化合物相同的共有12种,其中吡嗪类化合物8种、醛类化合物2种、醇类化合物1种、呋喃类化合物1种。     

Determination of volatile compounds formed in a glucose–selenomethionine model system by gas chromatography–atomic emission detector and gas chromatography–mass spectrometry

In order to gain a better understanding of the formation of organoselenium compounds in food system, the Maillard reaction of selenomethionine and glucose was studied in a model system. The effects of heating time and pH on the volatile compounds formed in a glucose–selenomethionine reaction were also investigated. Nine organoselenium compounds were identified. Pyrazines and dimethyldiselenide are major volatile compounds generated from the glucose–selenomethionine model system. A high pH level favours the formation of pyrazine and dimethyldiselenide. In unbuffered systems, a pH change of three or more pH units may occur, and this may significantly affect the formation of Maillard reaction products.