大豆磷脂产品质量控制——大豆磷脂的颜色和风味

综述了大豆磷脂颜色的来源 ,大豆磷脂褐色物质的生成。介绍了磷脂中产生各种气味的物质和油脂加工过程中混合油吸附过滤和脱色、水化脱胶工艺条件、脱胶剂对大豆磷脂颜色的影响。对磷脂制备工艺中常采用的过氧化苯甲酰、过氧化氢化学脱色法以及浓缩磷脂的白土脱色、浓缩磷脂活性炭吸附脱色作了介绍     

Performance of indigenous yeasts in the processing of Chinese strong‐flavoured liquor during spontaneous mixed solid‐state or submerged fermentation

To explore the in situ metabolic characteristics of yeasts involved in the spontaneous fermentation process of Chinese strong‐flavoured liquor, a comparison was conducted between solid‐state fermentation (SSF) and submerged fermentation (SmF) when supplemented with 24 indigenous yeast strains, with a focus on the production of ethanol and a broad range of volatile compounds responsible for the characteristics of Chinese strong‐flavoured liquor. Under the various experimental conditions, the 24 indigenous yeast strains showed different influences on the mixed fermentation system. The fluctuations caused by different yeast strains in the mixed system were less than those caused by the different fermentation modes relative to the formation of flavour compounds. SSF was found to be more suitable for the production of ethanol, methanol and ethyl lactate, whereas SmF was more suitable for the production of 10 higher alcohols, four esters and four acids. This study revealed the relationships amongst the indigenous yeasts, SSF, and the distinctive flavour profiles of Chinese strong‐flavoured liquor. This work provides evidence of the existence of internal stability in spontaneous SSF, thereby facilitating a better understanding of the fermentative mechanism in the SSF process for Chinese strong‐flavoured liquor production Copyright © 2015 The Institute of Brewing & Distilling     

Improvement of flavour compound synthesis in a mixed culture system at high temperature by solid‐state fermentation

In order to enhance the synthesis of flavour compounds in solid‐state fermentation (SSF) at a high temperature, Bacillus subtilis XJ‐013 and Saccharomyces cerevisiae Z‐06 were used as a mixed culture with Monascus HQ‐3. The culture temperature was enhanced from 37°C to 56°C by the synergetic effect, and the synthesis of esterase was enhanced from 85.43 U/g to 129.65 U/g in the mixed culture system (over 50% higher than that of the culture using a single strain). This resulted in the synthesis of favourable flavour compounds in the solid‐state fermentation. These results signified that a mixed culture of Monascus and S. cerevisiae was favourable for enzyme production. The mixed culture of Monascus and B. subtilis resulted in a high culture temperature that promoted flavour compound synthesis in the solid‐state fermentation system dramatically. These results present a model to explain the synergetic effects between the fungus and the Bacillus in the solid‐state fermentation. Copyright © 2015 The Institute of Brewing & Distilling     

Comparison of gas chromatographic volatile profiling methods for assessing the flavour quality of kenyan black teas

A comparison is made of the various ratios used to quantify black tea aroma such as: ratio of sum of gas chromatographic peak areas of compounds eluting before linalool (3,7-dimethyl-1,6-Octadien-3-ol) to those eluting after linalool (Wickremasinghe-Yamanishi ratio); gas chromatographic peak areas of compounds imparting sweet flowery aroma (Group II volatile flavour compounds) to those imparting green grassy aroma (Group I volatile flavour compounds), Owuor's flavour index; ratio of the sum of gas chromatographic peak area of the terpenoids to non-terpenoids, i.e. Mahanta ratio; and gas chromatographic peak area of linalool to E-2-hexena1, i.e. Yamanishi-Botheju ratio. The Wickremasinghe-Yamanishi ratio and Owuor's flavour index showed a significant relationship, the Mahanta ratio showed a significant but poor relationship, and the Yamanishi-Botheju ratio had no relationship with the tasters evaluation of Kenyan clonal CTC black teas. Similar results were obtained from orthodox black teas manufactured from different varieties.     

微囊化纯培养发酵剂发酵奶与藏灵菇奶的比较研究

利用从藏灵菇中分离出的优势菌,进行混合发酵,比较了这种纯培养菌种发酵的酸奶与藏灵菇发酵奶在感官、主要风味成分以及优势菌株数量的差异。HPLC检测结果表明,这2种发酵奶的乳酸产量分别为7.62 g/L和7.85 g/L,无显著差异;GC检测结果表明,微囊化纯培养发酵剂发酵奶中丁二酮的含量明显高于传统藏灵菇奶;GC-MS检测结果表明,2种发酵奶中挥发性风味成分有90%相同;感官评定表明微囊化纯培养发酵剂发酵奶的可接受程度显著高于藏灵菇奶。表明,微囊化纯培养发酵剂发酵奶既保持了藏灵菇奶原有的特征,又在风味上得到了进一步的提高,表明微囊化纯培养发酵剂可以替代藏灵菇进行这类发酵奶的规模化生产。     

Flavour index and aroma profiles of fresh and processed honeys

This paper discusses the importance of flavour profiling in detecting indicative parameters for quality control of fresh and heated honey. Flavour compounds of six unifloral honeys (Lavandula stoechas, Castanea sativa, Dorycnium pentaphyllum, Rosmarinus officinalis, Eucalyptus sp and Robinia pseudoacacia) were investigated. The aroma extracts were obtained by a two‐step procedure involving (i) preliminary steam distillation under reduced pressure to evaluate the methylpyrazines generated in heated honeys by spectrophotometry (flavour index) and (ii) Likens–Nickerson's simultaneous steam distillation and solvent extraction (SDE) method with added NaCl. A combined total of 64 compounds were detected by gas chromatography/mass spectrometry (GC/MS), 58 of which were identified. Some compounds appeared to be characteristic of the floral source, particularly in Spanish lavender (methylated aliphatic acids and aromatic esters), eucalyptus (2,3‐pentanedione, acetoin, 1‐hexyl alcohol, 2‐acetyl‐5‐methylfuran, furfuryl propionate, 2‐phenylacetaldehyde and nerolidol), chestnut (acetophenone and 2‐aminoacetophenone), rosemary and D pentaphyllum (aromatic acids and esters, 2‐phenylacetaldehyde, farnesol and thymol) honeys. Robinia honey samples were characterised by very low levels of aromatic compounds. Twenty‐six flavour compounds were statistically closely related to the floral origin of the honeys (P ≤ 0.05). The flavour index was evaluated progressively in heated honeys, whereas in fresh honeys it showed a minimal value. © 2003 Society of Chemical Industry     

白瓶啤酒生产的问题与解决措施

白瓶啤酒现在成为啤酒家族的新宠,但随之也出现了一些问题,本文着重解释了解决这些问题的各种工艺措施。     

Variations in the leaf standard,chemical composition and quality of black tea (Camellia sinensis) due to plucking intervals

Green leaf standard, chemical composition and quality of black tea (Camellia sinensis (L) O Kuntze) change with plucking intervals. Long plucking intervals lead to poor leaf standard with a lot of mature leaves and lower theaflavins, the sum of volatile flavour compounds imparting a sweet flowery aroma (group II volatile flavour compounds), caffeine contents and tasters' evaluations of black tea. The sum of volatile flavour compounds imparting inferior, grassy, green flavour (group I volatile flavour compounds) to tea, however, increases with long plucking intervals.     

瓶装黄酒杀菌条件与风味关系研究

对瓶装黄酒杀菌温度、时间等对酒质、风味的影响作了系统的研究和分析。实验表明：杀菌温度在60℃-65℃，随杀菌时间延长酒质得到改善；当杀菌温度超过70℃时，杀菌时间应控制在1h以内；当75℃时杀菌超过30min，黄酒风味有下降的趋势；80％以上，黄酒风味随杀菌时间延长而变劣。