Sensory and Nutritional Properties and Stability of Formulated Organic Food Flavour Enhancers

Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins and minerals in our two products justify their umami taste and can be used as highly nutritional food flavour enhancers to prevent cardiovascular diseases, especially in the elderly.

Effects of molybdenum on nutrition, quality, and flavour compounds of strawberry (Fragaria×ananassa Duch. Cv. Akihime) fruit

Molybdenum （Mo） is an essential trace element in plant nutrition and physiology. It affects photosynthesis and photosyn- thate accumulation, therefore also affecting fruit quality and nutritional content. This study assessed the effects of different sodium molybdate （Na2MoO4） concentrations on strawberry. Five different Mo concentrations were applied in this experi- ment, including 0, 67.5, 135, 168.75, 202.5 g ha-1, respectively. The mineral concentration, including nitrogen （N）, Mo, iron （Fe）, copper （Cu）, and selenium （Se） was assessed in strawberry fruit, as well as chlorophyll content, nutrition quality, taste and aroma. Results showed that net photosynthetic rate （Pn） and chlorophyll content for the strawberry plants increased with an increase in Mo concentration; and the contents of N, Mo, Fe, Cu, total soluble solids （TSS）, titratable acidity （TA）, sweetness, some sugars, organic acids, and some volatile compounds in the fruit all increased, as well. However, the Mo concentration did not significantly affect the concentrations of Se, sucrose, lactic acid, acetic acid, and some aroma compounds. Fruit sprayed with 135 g ha-1 Mo exhibited the highest TSS and sweetness values, as well as the highest N and Fe concentrations among all the treatments. P value and chlorophyll content, fructose, glucose, sorbitol and total sugar contents in fruit supplied with 135 g ha-1 Mo were also higher than that in other treatments. Fruit sprayed with a Mo concentration of 67.5 g ha-1 exhibited significantly higher ascorbic acid （AsA） values than that of control. Ninety-seven volatile compounds were identified in fruit extracted by head-space solid-phase microextraction （HS-SPME） coupled with gas chromatography-mass spectrometry （GC-MS）. Fruits sprayed with 135 g ha-1 Mo had the highest concentrations of six characteristic aroma compounds, including methyl butanoate, y-decalactone, ethyl butanoate, methyl hexanoate, y-do- decalactone, and ethyl caproate.

Flavour and Colour of Quarks in Spin Topological Space

An assumption that all the six flavour quarks are attributed to be the components of a same, a common isospin multiplets space named STS is proposed. Base on Pauli Exclusion Principle, every quark is assigned to different flavour marks in STS. Every flavour quark possesses its own colour spectral line array specially appointed. The collection of colour spectral line arrays of the six flavour quarks constructs together the CSDF, Colour Spectrum Diagram of Flavour, further baryons and mesons could be constructed from CSDF. STS, Spin Topological Space is a math frame with infinite dimensional matrix representation for spin angular momentum. Flavours is an isospin angular momentum coupling phenomena of the three-colour-quarks.

Flavour Behavior

A good flavour must taste realistic and natural as well as performing under tough conditions, says Mairi Coia. In conjunction with texture or mouthfeel, flavour is the most important aspect of food. It is the one thing can bring consumers back to a product again and again - or not, as the case may be. In short, taste is the number one attribute in food and that is why the global fiavour business is worth A5 billion every year as manufacturers strive to make food taste better and fresher for longer.……

Multiple Seasonal Modifications in Enzymatic Flavour Formation in Tea

Carotenoid cleavage enzymes isolated from Japanese Camellia sinensis leaves(cultivar Yabukita) were used for investigating the structural patterns of carotenoid cleavage enzymes.Fresh tea leaves were used for the isolation of active enzymes and purified to single band stage in SDS PAGE gels after isoelectric focusing.The specific activity of the carotenoid cleavage enzymes was tested and the active fractions selected for further analysis.The sugar content and the amount of phosphate present in the purified enzymes were elucidated by the following methods:Phosphates were detected by phosphatase assays,fluorescence marker kits and ammoniumheptamolybdate complex measurements after incineration of the samples.Sugars were detected in gels using PAS reagent(periodide acid /Schiff reagent) staining and by GC-MS after hydrolysation of the proteins with trifluoric acid.Phosphorylations as well as glycosylations of the samples could be detected in all cases,thus giving evidence for an increasing phosphorylation level of proteins in Camellia sinensis from spring(1.84 g/mg) to autumn(2.39 g/mg) as well as the presence of at least four different sugars(arabinose,xylose,galactose and ribose).These secondary modifications of the carotenoid cleavage enzymes and their dependency on the harvesting season may well correspond to the changes on the functional level which were detected between spring(Michaelis Constant(K m) =9.45 mol/l) and autumn(K m= 17.16 mol/l) harvests.

Heavy flavour physics and CP violation at LHCb:Aten-year review

Heavy flavour physics provides excellent opportunities to indirectly search for new physics at very high energy scales and to study hadron properties for deep understanding of the strong interaction.The LHCb experiment has been playing a leading role in the study of heavy flavour physics since the start of the LHC operations about ten years ago,and made a range of high-precision measurements and unexpected discoveries,which may have far-reaching implications on the field of particle physics.This review highlights a selection of the most influential physics results on CP violation,rare decays,and heavy flavour production and spectroscopy obtained by LHCb using the data collected during the first two operation periods of the LHC.The upgrade plan of LHCb and the physics prospects are also briefly discussed.

Effects of nitric oxide treatment on flavour compounds and antioxidant enzyme activities of button mushroom (Agaricus bisporus) during storage

Button mushroom(Agaricus bisporus)is sold well for its unique flavour and nutritional benefits.However,the mushroom flavour deteriorates quickly during storage because of its delicate structure and high moisture.In this study,the effects of nitric oxide(NO)application on flavour compounds and antioxidant enzyme activities of stored button mushrooms were investigated.The button mushrooms were immersed in the NO donor sodium nitroprusside(15μmol/L)for 3 min and then stored under the condition of 4℃,90%relative humidity for 12 days.Results showed that the treated mushrooms have reduced weight loss rate,uniform white colour,and higher firmness during storage.Compared to the control,the ketones,alcohols,esters,and aldehydes in the NO-treated button mushroom increased sharply at 3 days of storage and then showed a continuing decline trend,except ester compounds which reached the peak value at 6 days of storage.In addition,NO treatment increased the total phenolics and catalase activity and inhibited the polyphenol oxidase activity in the stored button mushroom.These results indicated that NO treatment is an alternative storage technology to enhance antioxidant capacity and maintain flavour and consumer acceptance of stored button mushroom.

Proton sea quark flavour asymmetry and Roper resonance

We study the proton and the Roper resonance together with the meson cloud model, by constructing a Hamiltonian matrix and solving the eigenvalue equation. The proton sea quark flavour asymmetry and some properties of the Roper resonance are thus reproduced in one scheme.

Measurement of (di)muons from heavy flavour decay in p-p collisions at 14 TeV with ALICE at the LHC

We present the performance of the ALICE muon spectrometer for measuring the charm and beauty inclusive p t differential production cross sections via single muons and unlike-sign dimuons in proton-proton collisions at√ s = 14 TeV.

Tasting Exotic Cultural Flavour in Lijiang

The New Millennium has brought a renewed focus onto China's abundance of world heritage sites. Up to now, 21 scenic spots in China have been included in the list of world heritage sites by the UNESCO and some others are in the process of application. Scattered over the country, these places are the gems of Chinese tourism resources. We have chosen two of them to offer to our readers. First is the unique charm of ancient Lijiang County in China's southwestern frontier province, Yunnan. Some time later, we wi...

加工方式对大豆油中挥发性物质的影响

为探究加工方式对大豆油风味物质的影响,采用电子鼻与顶空固相微萃取-气相色谱-质谱联用相结合的方法分析浸提、热榨和冷榨3种方式加工的大豆油挥发性物质的差异。结果表明:在3种大豆油样品中共检出86种挥发性物质,其中浸提油53种,热榨油54种,冷榨油45种,主要包括醛类、醇类、酮类、酸类、酯类、萜烯类、杂环类(呋喃和吡嗪)以及烃类等化合物。在3种大豆油中检出相同的挥发性物质有24种。主成分分析和层次聚类分析结果表明加工方式对大豆油风味的影响较大。采用气味活度值(OAV)判定3种大豆油样品的关键风味物质,浸提油中检出关键风味物质15种,以3-壬烯-2-酮等物质为主,使浸提油具有浆果风味。热榨油中检出关键风味物质16种,其中2,5-二甲基吡嗪等杂环类物质使热榨油具有独特的烘焙风味。冷榨油中检出12种关键风味物质,以(E,E)-2,4-庚二烯醛等醛类物质为主,使冷榨油具有天然油脂风味。偏最小二乘回归分析表明电子鼻与气相色谱-质谱联用的检测结果间存在较好相关性。

凝胶涂层包覆大孔树脂固定化脂肪酶的制备及在风味酯合成中的应用

风味酯是一种重要的香料化合物,在食品、化妆品和制药等行业具有重大的应用价值。酶法合成风味酯具有反应条件温和、选择性高以及污染少等优点,但在有机溶剂中,游离脂肪酶的活性会有极大的损失。为了提高脂肪酶的稳定性,该研究首先使用大孔树脂通过吸附作用固定化脂肪酶,然后对酶蛋白表面进行丙烯酰化修饰和聚合反应,在固定化脂肪酶的表面形成凝胶涂层的包覆。此种方式制备的固定化脂肪酶稳定性有了较大提高。利用该固定化酶分别通过酯化反应合成乙酸丁酯和转酯反应合成乙酸异戊酯,结果显示,以正庚烷为溶剂,乙酸和丁醇浓度均为0.1 mol/L,并添加1 g固定化酶,在45℃经过12 h的反应,乙酸丁酯的合成率达到93.05%,重复利用4次后仍然有70.83%的酯合成率;在3 mL乙酸乙烯酯溶液中加入0.8 mol/L异戊醇和0.5 g固定化酶,在45℃经过14 h的反应,乙酸异戊酯的合成率达到92.35%,重复利用4次后仍然有84.80%的酯合成率,研究建立了一种固定化脂肪酶的新方法,并为风味酯的制备奠定了基础。。

Co-inoculation of Debaryomyces hansenii and lactic acid bacteria: a strategy to improve the taste and odour profiles of dry sausages

The effects of the co-inoculation of Debaryomyces hansenii separately with 3 lactic acid bacteria(LAB),Lactobacillus sakei,Lactobacillus plantarum and Lactobacillus curvatus,on the taste and odour profi les of dry sausages were investigated.The co-inoculated sausages showed higher free amino acid and organic acid contents than the non-inoculated control and sausages inoculated with D.hansenii alone.Meanwhile,the sausages inoculated with D.hansenii+L.plantarum,D.hansenii+L.sakei and D.hansenii+L.curvatus had the highest contents of aldehydes,esters and alcohols,respectively.The results of electronic tongue,electronic nose and sensory evaluation demonstrated that compared with the sausage inoculated with D.hansenii,the sour taste and fl oral odour increased and the fatty odour decreased in the sausage inoculated with D.hansenii+L.sakei;this was more favourable for the development of a desirable fl avour in sausages.Moreover,the partial least squares regression analysis indicated that 10 taste and 33 odour compounds were mainly responsible for the differences in the flavour profiles among the sausages.Overall,these findings contributed to a more comprehensive understanding of the formation of sensory characteristics in dry sausages co-inoculated with yeast and LAB.

地方性知识如何参与乡村媒介行动:“土味”短视频传播的人类学考察

人类学有关地方性知识的论说,以“情境”“特定”“专属”等特征与前现代/传统社会的特定时空、地方和人群相联系。在传媒技术、话语生态快速迭代的当前社会语境下,众多“土味”短视频凭借低门槛、高弥散的媒介技术属性全面介入日常生活,也在中国城乡关系的重构过程中拓展了地方性知识嵌入媒介社会行动的新讨论空间。本研究凸显媒介空间地方性知识的实践面向,基于一个西北乡村媒介生活图景的民族志深描,从符号人类学视域出发考察乡村日常生活的符号化与媒介化的具身实践,观照“刷”短视频这一微观身体操演中隐含的知识平权、信息扁平和基层主体身份意识的建构和表达,从而在媒介符号“可见性”“可供性”与“可刷性”的复杂关联中看到,地方性知识不仅作为一种知识要素嵌入了“土味”乡村的媒介符号图景,也作为重要的行动路径折射出乡村民众从“地方”这一特定历史位置参与当下媒介世界的复杂经验和主体意义。

电子鼻结合气相色谱-离子迁移谱法鉴别不同干燥方式的膳食虾肉复合果蔬棒风味变化

目的 探究真空冷冻干燥及热风干燥处理膳食虾肉复合果蔬棒的风味变化。方法 采用电子鼻定性分析两种干燥方式下的复合果蔬棒的区别,并利结合气相色谱-离子迁移谱法(gaschromatography-ionmobility spectrometry, GC-IMS)定量分析两种干燥方式样品的区别。结果 通过电子鼻数据结果分析新鲜样品与两种干燥方式获得的样品存在明显区别,GC-IMS结果检测得到62种挥发性风味物质。其中在经过热风干燥的膳食虾肉复合果蔬棒中正丁醇、苯甲醇、3-呋喃甲醇等醇类物质的含量比冷冻干燥的含量高;酯类中的戊酸丁酯、庚酸甲酯等热风干燥较冷冻干燥含量多,而部分酮类化合物在干燥过后的含量有所降低。结论 经过冷冻干燥后的样品在保持原有样品的形态颜色等优于热风干燥,从电子鼻以及GC-IMS的结果获得热风干燥的愉快型风味物质含量增加,本研究结果可作为今后膳食虾肉复合果蔬棒以及类似相关的复合产品的深加工方式选择和开发提供理论依据。

直投式菌种和母液发酵白酸汤的品质比较

白酸汤作为贵州凯里特色调味品,深受人们喜欢,但存在产量低、品质不稳定等问题。以直投式菌粉(干酪乳杆菌、植物乳杆菌)和白酸汤母液作为复合发酵剂接种发酵白酸汤,以单一母液发酵白酸汤作为对比,研究白酸汤发酵过程中理化、微生物指标及感官品质的变化规律;利用液相色谱-质谱及全二维气相色谱-飞行时间质谱技术,对比分析2组白酸汤风味物质的差异。结果表明,发酵结束时,接种发酵组(Inoculated Fermentation-7d,IF-7)的总酸及乳酸菌总数均高于自然发酵组(Natural Fermentation-7d,NF-7),pH值及酵母菌总数则低于NF-7组;IF-7组的感官评分在色泽、风味、滋味和总分方面均高于NF-7组,流动性无显著性差异;在对非挥发性风味物质的研究中,IF-7组共有21种具有显著差异的代谢物高于NF-7组,6种代谢物低于NF-7组;在对挥发性风味物质的研究中,IF-7组和NF-7组分别检测出248种和246种成分,主要为醇(以丙醇、乙醇等为主)、酸(以乙酸、丙酸等为主)及酯类物质(以乙酸丙酯、丙酸丙酯、乙酸乙酯等为主),IF-7组酯类物质含量略低于NF-7组,其他方面差异较小。以上结果表明,以直投式菌粉和白酸汤母液作为发酵剂接种发酵白酸汤能明显缩短生产时间,提升产品品质及营养价值。

基于搅拌棒固相萃取-气相色谱-质谱/嗅辨同步分析法的污染河道水异味分析

采用搅拌棒固相萃取-气相色谱-质谱/嗅辨同步分析法分析上海市某污染河道水样,根据NIST谱库对色谱分离出的化合物进行定性,借助峰面积归一化法采用相对含量对这些化合物进行半定量分析,结合嗅辨结果(嗅辨时间、气味类型、气味强度)确定异味来源。结果表明,污染河道水样中化学需氧量较高,说明水样中有机污染物含量较高,但是水样中不含常见的挥发和半挥发性有机污染物,主要源于相对含量较高的醇类、醚类物质,但是这两类物质没有明显臭味。结合气相色谱-质谱结果以及嗅辨结果综合分析得出,水体恶臭是由相对含量低于1.00%的含硫化合物(硫醇、噻吩)、含氮化合物(吲哚、吡啶)、烃类化合物(烷烃、烯烃、芳香烃)以及含氧有机物(醇、酮、醚)等综合作用的结果。

GC-MS结合电子鼻、电子舌分析6种糖炒燕山板栗的风味成分

为了研究6种糖炒燕山板栗香气的构成特点及品种间滋味和气味上的差异。以6种糖炒板栗为原料,采用顶空固相微萃取-气相色谱-质谱联用(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)技术及气味活性值(Odor activity value,OAV)法分析6种糖炒板栗的挥发性风味成分和关键香气化合物,并结合电子鼻和电子舌对其挥发性气味成分和滋味进行分析。结果表明,通过GC-MS技术从6种糖炒板栗的挥发性成分中共检测出57种化合物,其中酯类19种,醇类12种,醛类5种,酮类5种,烯烃类4种,苯环类4种,胺类2种,其他类6种;其中23个OAV>1的成分被确定为糖炒板栗的关键香气成分。电子鼻评价结果显示6种糖炒板栗的主要挥发性气味成分为醇类、醛酮类、氮氧化合物、有机硫化物、无机硫化物以及甲基类几种。电子舌评价结果显示6种糖炒板栗在各项味觉指标上整体较为相似,其中丰富性和鲜味传感器对不同糖炒板栗的响应值最大,酸味和涩味最小,丰富性、鲜味、甜味、咸味、苦味、苦味回味6个指标为糖炒板栗的主要味觉指标。6种糖炒板栗的挥发性风味成分和含量都存在一定的差异,即不同品种糖炒板栗中的挥发性风味成分不同,且同种化合物在不同品种间的含量也有区别。通过主成分分析(Principal component analysis,PCA)、雷达色谱图分析、GC-MS技术结合电子鼻/电子舌可较好的区分不同品种糖炒板栗风味的差异,并确定其关键香气成分,为不同糖炒板栗的风味研究提供理论依据。

Pichia kudriavzevii生物强化对酱香型白酒酒醅微生物群落结构及挥发性风味组分的影响

乙酸苯乙酯具有玫瑰花香、蜂蜜香、苹果香等风味特征,是酱香型白酒的重要风味物质。高产乙酸苯乙酯酵母菌的筛选及发酵应用对于改善酱香型白酒风味,提高白酒品质具有重要意义。从酱香型白酒酿造过程的酒醅样品中筛选得到1株乙酸苯乙酯产量相对较高的菌株Pichia kudriavzevii X-8,将其应用于酱香型白酒模拟发酵实验。结果表明:A组(未添加菌株Pichia kudriavzevii X-8)和B组(添加菌株Pichia kudriavzevii X-8)酒醅样品中挥发性化合物分别有60、65种,其中B组的酯类、醇类、酸类及其他风味物质的种类及含量均高于A组。发酵30 d后,B组乙酸苯乙酯质量比(0.214μg/g)约为A组(0.121μg/g)的2倍。B组特有的优势属为Weissella和Pichia,2组酒醅样品中Lactobacillus和Pediococcus,Saccharomycopsis和Saccharomyces的菌落丰度也存在差异。加入Pichia kudriavzevii X-8后,对酒醅的理化指标影响不大,增强了水质量分数、酸度及风味物质与真菌属微生物的相关性,提高了乙酸苯乙酯及其他重要风味物质的含量。研究结果旨在为酱香型白酒品质提升和功能菌株在酱香型白酒中的实际应用提供理论参考。

加工对肉类蛋白质氧化及肉品品质影响的研究进展

肉类是人类日常饮食中的重要组成部分,其品质对于消费者的健康和口感体验至关重要。动物在被宰杀后的胴体向食用肉转变和肉品加工过程中,经历复杂的生化反应,其中蛋白质氧化对肉类品质的形成具有重要影响。本文主要针对蛋白质氧化对肉类品质的影响,结合蛋白质氧化产物的类型,加工方式、条件等影响因素,总结了目前加工条件下蛋白质氧化与肉品质变化的关系,旨在为控制肉品蛋白质的氧化提供理论依据,并为实际生产提供科学指导。