我国食用香料香精的基本状况与发展趋势

食用香料是食品添加剂中数量最多、使用面较广的一类添加剂。近几年我国食用香料香精发展较快,国标GB2760-1996中规定的允许使用的食用香料总共有1283种,本文对我国的食用香料香精的发展趋势进行了简单论述。     

Headspace Congeners of Blended Scotch Whiskies of Different Product Categories from SPME Analysis

Flavour congeners in headspaces of 40 blended Scotch whiskies, of 4 different product categories (Deluxe, standard, retailer and West Highland), were collected by solid phase micro extraction (SPME) over 10 ml diluted (23% abv) whisky. Fibres (100 μm diameter) were thermally desorbed for 5 min in a split/splitless injection port and congeners quantified by high resolution gas chromatography. Two bonded SPME phases (polydimethylsiloxane and polyacrylate) were evaluated: exposure time was varied between 5 and 30 min; with whisky at either nosing (25°C) or tasting (37°C) temperature. Optimal analysis was with polyacrylate fibres at 37°C for 15 min but extraction at 25°C generated data relevant to sensory (nosing) data. Principal component (PCA) and discriminant partial least square (DPLS) analyses of mean % peak areas for all 57 resolved HRGC components and congeners (38) common to all whiskies gave product spaces showing clear separation of Deluxe, retailer and West Highland blends, but dispersed standard blends. In DPLS2 product clustering was similar whether relative (%) or absolute peak area was used in analyses but congeners loadings differed. From product spaces it was possible to assess contributions of flavour congeners, mainly esters and alcohols, to headspaces of individual blends and product categories.     

淡爽型啤酒生产技术的研究

以麦芽、大米、酒花为原料 ,对不同比例的麦芽用量作了小试 ,认为用45 %较55%为佳 ;辅料大米以37%为好 ,糖化pH5.2～5.4,糊化pH6.0～6.3,煮沸90min ,第一次加酒花2kg,第二次加酒花9kg,第三次加酒花7kg,接种酵母7.0‰ ,发酵最高温度12℃ ,最高压力0.12MPa,发酵第6天开始测双乙酰 ,当双乙酰降至0.8×10-7时 ,保温48h ,再以0.3℃/h降至0℃ ,后酵7天以上。成品酒理化指标达GB4929—91优级标准。     

配醅串香工艺在浓香型白酒生产中的应用

根据甑桶蒸馏提香的充分条件,在生产中采取配醅串香工艺,将香醅,酒醅的蒸馏与发酵有机地组合起来,较好地解决了传统蒸馏方法中香味物质利用率低的问题,生产应用表明,配醅串香工艺能在稳定出酒率的基础上,提高优质品率13．1％,主体香味物质提高20％左右。     

白兰地的蒸馏理论

白兰地中的挥发性化合物有的来源于葡萄原料,有的在发酵过程中形成,通过蒸馏进入粗馏白兰地,形成白兰地特有的香味,在蒸馏过程中,低沸点成分不发生化学变化,含量基本保持不变,高沸点成分要发生化学变化,有些物质的含量有所增加或减少,有些物质将重新形成,显著增长的是醛（74％）和酯类（17．4％）,此外,蒸馏过程中还发生物质的分解,由于高温,中间氧化剂和溶解氧的存在,使酒精氧化成乙醛和乙酸,酯化作用的同时发生酯的分解,用铜,铁蒸馏釜蒸馏,挥发性成分形成多,用玻璃烧瓶蒸馏,挥发性成分形成少。     

Spanish Melon Landraces: Revealing Useful Diversity by Genomic,Morphological, and Metabolomic Analysis

Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation.     

黄油的研究进展

近年来国内黄油的贸易量、关注度和研究热度显著上升。黄油开发及创新面临着如何提升感官特性、健康品质和绿色发展水平等多重挑战。作者综述了黄油市场及国内外研究现状,分析了未来黄油研发的重点方向与解决方法,重点探讨了未来黄油的原料创新和技术创新方式,旨在为当前黄油生产和新型黄油开发提供参考。     

大豆食品豆腥味研究进展

大豆食品营养丰富,含有多种生理活性物质,但是大豆食品中往往具有不同程度的豆腥味,许多人难以接受,从而限制了大豆食品的发展和广泛食用。本文就大豆食品中豆腥味的来源以及豆腥味的消除方法进行了综述。     

不同超高压处理压力对哈密瓜汁香气的影响

采用固相微萃取方法对不同超高压处理的哈密瓜汁的香气进行富集 ,并经GC MS联机检索分析 ,发现超高压处理对哈密瓜汁中的酯类、醇类、醛类和酮类都有影响 ,其中超高压处理哈密瓜汁的酯类减少了 5种且峰面积减少了约 10 % ,而醛类和酮类增加。 5 0 0MPa/2 0min处理的哈密瓜汁与 40 0MPa/2 0min处理的哈密瓜汁相比 ,酯的种类和峰面积变化不大 ,酮的种类没有变化 ,但增加了 3种不饱和醛。 2种超高压条件处理的哈密瓜汁酯类的特征香气成分未变 ,但醇类和醛类的特征香气成分变化较大。感官评定表明 :超高压处理的哈密瓜汁的香气减弱 ,青鲜气增强 ,这与哈密瓜汁香气成分检测的结果相符合。