Application of liquid chromatography-nuclear magnetic resonance spectroscopy for the identification of ethyldimethylpyrazine, a food flavouring agent

The application of liquid chromatography-nuclear magnetic resonance spectroscopy (LC-NMR) for the direct identification of ethyldimethylpyrazine, a food flavouring agent, has been studied. The commercial product is a mixture of two regio-isomers, 2-ethyl-3,5-dimethylpyrazine (1) and 2-ethyl-3,6-dimethylpyrazine (2); however, the exact composition of the mixture is unknown. Structural characterization by LC-MS and GC-MS was not possible because both regio-isomers yield the same molecular related ion and ion fragmentation. To rapidly identify the two regio-isomers, the product was analyzed by LC-NMR with on-flow and fraction loop modes. From the results, the structure elucidations of the two regio-isomers could be carried out without the need to isolate the isomers by the usual procedures.     

基于菜肴呈味的构成元素论调味

味是中国菜肴的灵魂,而菜肴呈味构成元素有菜肴主料、调味原料相互作用、菜肴处于环境及人们食用特点等.调味是烹制菜肴三大核心技术之一,文章通过剖析制约菜肴呈味的元素,进一步提出菜肴合理调味的方法,利于菜肴味的形成.     

Seafood flavourings characterization as prepared from the enzymatic hydrolysis of Undaria pinnatifida sporophyll by-product

Protein by-products from Undaria pinnatifida (U. pinnatifida) sporophyll processing (i.e., after polysaccharide extraction) were hydrolysed using flavourzyme (enzyme activity = 7592 U/g). Optimal hydrolysis conditions were determined using response surface analysis (i.e., 7% flavourzyme for 18 h); a hydrolysate yield of 32.52 ± 0.46 g/100 g dry-solids was achieved with a degree of hydrolysis (DH) at 5.63 ± 0.27 g α-amino nitrogen/100 g total nitrogen. Five free amino acids (FAAs), alanine, glumatic acid, aspartic acid, proline, and glycine, were abundant in the best hydrolysate. Eighteen volatile flavour compounds were identified using gas chromatography/mass spectrometry, with hexanal, cedrol, nonanal, 2-heptenal, acetoin, and heptanal being the primary odorants. As indicated by the sensory panel, the hydrolysate from U. pinnatifida sporophyll by-products (HUPSB) exhibited an umami taste and a seaweed odour. It was concluded that the protein by-products of U. pinnatifida sporophyll processing could yield excellent seafood flavouring.     

食用香精香料的现状及发展趋势

从香精香料的来源、分类、应用、国内外香精香料的发展对比以及香精香料的分析方法等方面对香精香料的现状及发展趋势和香精香料行业标准作了系统地阐述。     

Review of the regulation and safety assessment of food substances in various countries and jurisdictions

This review compares the regulations, definitions and approval processes for substances intentionally added to or unintentionally present in human food in the following specific countries/jurisdictions: Argentina, Australia, Brazil, Canada, China, the European Union, Japan, Mexico, New Zealand, and the United States. This includes direct food additives, food ingredients, flavouring agents, food enzymes and/or processing aids, food contact materials, novel foods, and nanoscale materials for food applications. The regulatory authority of each target jurisdiction/country uses its own regulatory framework and although the definitions, regulations and approval processes may vary among all target countries, in general there are many similarities. In all cases, the main purpose of each authority is to establish a regulatory framework and maintain/enforce regulations to ensure that food consumed and sold within its respective countries is safe. There is a move towards harmonisation of food regulations, as illustrated by Australia and New Zealand and by Mercosur. The European Union has also established regulations, which are applicable for all member states, to establish a common authorisation procedure for direct food additives, flavourings and enzymes. Although the path for approval of different categories of food additives varies from jurisdiction to jurisdiction, there are many commonalities in terms of the data requirements and considerations for assessment of the safety of use of food additives, including the use of positive lists of approved substances, pre-market approval, and a separation between science and policy decisions. The principles applied are largely reflective of the early work by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) committees and JECFA assessments of the safety of food additives for human and animal foods.     

我国食用香精香料工业的发展现状及对策

我国是食用香精香料的生产大国,随着食品工业的快速发展,食用香精香料发挥了越来越重要的作用,但我国食用香精香料工业存在的生产设备、工艺落后等问题制约着它的进一步发展。因此,文章论述了国内外香精香料工业的发展现状,食用香精香料的分类和制备方法,分析了我国食用香精香料工业存在的问题并提出了相应的发展对策。     

黄水调味液在白酒调味中的应用

黄水调味液是黄水在高活性生物酶的作用下，经催化热裂后的馏出液。采用它对白酒进行调味，能改善酒质，赋予白酒自然感，同时可以降低生产成本，减少污染。     

扇贝裙边酶解中温度对氨基氮的影响和抑臭工艺的确定

酶解法由扇贝边制取海鲜调味料,关键在于获得高氨基酸含量的酶解液和抑制酶解过程中臭味的产生。本文报道了主要参数温度对酶解过程的影响和加糖抑臭工艺。按本文所述方法,加入1%～3%的糖,控制酶解温度波动范围<3℃,可消除或推迟臭味的产生,酶解液中氨基氮含量可达0.9%以上。     

热反应肉香风味调味料

介绍了肉香风味调味料的开发历程，论述了热反应肉香风味调味料的天然性、高科技性及其调味功能，最后介绍了热反应肉香风味调味料在方便面中的应用。     

茶饮料的风味调配

了解茶饮料的调配原理和调配技术是开发和生产品质优良、风味独特茶饮料的关键。而茶饮料的风味调配又是茶饮料加工的关键工序。主要介绍了茶饮料风味调配的原理、程序和方法，以期对茶饮料加工企业的生产有所帮助。