卷烟薄荷香型微胶囊颗粒的制备及其应用研究

选用HI-CAP、CAPSUL和CAPSUL TA三种OSA变性淀粉与蔗糖和麦芽糊精1:1:1的复配溶液为壁材,以薄荷香型烟用香精为芯材,采用喷雾干燥工艺制备薄荷香型烟用微胶囊;并采用顶空制粒工艺,制成颗粒应用到卷烟中。应用SEM扫描电镜和热重分析对微胶囊产品进行了表征,并测试了微胶囊颗粒的包埋率、储存稳定性与释放特性。结果表明:利用OSA变性淀粉作为壁材所制备的微胶囊颗粒具有连续、致密的结构。其中,使用CAPSUL变性淀粉包埋的微胶囊颗粒包埋率更高,达到了95.26%,其对薄荷香精保留和延长时间的效果优于HI-CAP和CAPSUL TA变性淀粉,储存30 d后薄荷油保留率在92.76%,在保温温度为80 ℃条件下,薄荷醇释放率达到51%。应用到卷烟中可以提高薄荷香型特征烟用香精的释香时间,改善卷烟感官质量。     

薄荷香精微胶囊的内乳化凝胶法制备及性能研究

薄荷香精在食品生产中应用广泛,但是由于其易挥发性和对环境敏感的特性,致使留香时间不长,货架期较短。目前,喷雾干燥是最广泛使用的微胶囊制备方法,但是由于喷雾后的高温干燥处理会导致香精的部分损失,所以需要探索一种在常温下制备香精微胶囊的方法。本文以海藻酸钙为壁材,薄荷香精为芯材,采用内乳化凝聚法来制备薄荷香精微胶囊,在常温下可获得球形好、粒径分布均一的微胶囊。通过傅立叶红外光谱定性验证香精是否被海藻酸钠包埋。由单因素实验和正交实验对包埋率和粒径分布进行考察,得到制备的最佳工艺参数。最佳的工艺条件为:芯材与海藻酸钠质量比1:3,海藻酸钠质量分数为4%,Span-80添加量2%,冰醋酸与碳酸钙摩尔比3:1,碳酸钙与海藻酸钠质量比7:40,乳化时间15 min。此条件下薄荷香精微胶囊的包埋率为59.63±0.47%,平均粒径为290.70μm。用差示量热扫描仪(DSC)对其热稳定性能进行分析,发现微胶囊可以对香精起到部分缓释作用。     

阿拉伯胶对滤棒薄荷香精微胶囊缓释性能的影响

研究了阿拉伯胶对高压静电法制备滤棒薄荷香精微胶囊的影响.实验结果表明:阿拉伯胶的加入能够增强乳液抑制香精释放的效果;阿拉伯胶加入量不超过1.5%时,对香精包埋率保持在70%以上;正交实验得出,当海藻酸钠添加1.7%、吐温80添加2.0%、阿拉伯胶添加0.9%时,包埋率最高为75.6%;复合壁材香精微胶囊能更好地抑制香精的释放.     

茉莉香精微胶囊的制备和表征

通过界面聚合方法,在水包油体系中以聚氨酯为囊壁材料将香精包覆形成一种微胶囊,考察了乳化剂用量、搅拌速度对微胶囊的形成、粒径大小和分布及对微胶囊包埋率和缓释性能的影响,确定了制备缓释型香精微胶囊的最佳工艺条件,用红外光谱表征了香精及其微胶囊的包裹情况,并用紫外分光光度计测定了其缓释性能,将制得的香料微胶囊在毛巾和棉布上进行芳香整理。     

相分离-凝聚法制备薄荷醇微胶囊试验

由于薄荷醇具有很强的挥发性 ,因此 ,在薄荷卷烟生产、运输、贮存和销售期间薄荷醇极易挥发逸失。为了解决这个问题 ,进行了采用相分离 -凝聚法对制备薄荷醇微胶囊研究。结果表明 ,薄荷醇的被包裹率可达 5 8.7%。微胶囊较好地增强了卷烟保留薄荷醇的能力 ,并改进了薄荷卷烟的吸味品质。     

高效装载的水溶性薄荷醇微胶囊的制备研究

以麦芽糊精和麦芽糖作为壁材,以变性淀粉为乳化剂将薄荷醇封存于稳定的玻璃态结构中,采用喷雾干燥法制备了薄荷醇微胶囊。利用原子力显微镜对其形貌进行表征发现薄荷醇微胶囊呈球形,大小在13μm之间,动态光散射法测量出微胶囊的平均粒径为1.75μm。分光光度法对微胶囊的总薄荷醇含量和表面薄荷醇含量进行定量研究,结果表明制备的薄荷醇微胶囊具有高的保留率、包埋率和微胶囊化效率。微胶囊化薄荷醇的水溶性好、稳定性强,使它可以广泛应用于食品、饮料、烟草、保健药品中。     

GC-MS测定二次包埋法及β-环糊精制备葱油香精微胶囊热稳定性的比较研究

探讨了以葱油香精为芯材,用二次包埋法(复凝聚结合喷雾干燥法)和β-环糊精对其进行微胶囊化,分别在2种方法的最佳工艺条件下制备葱油香精微胶囊。扫描电子显微镜对比观察显示,二次包埋法包埋所得微胶囊产品比β-环糊精法所得产品更具有典型的微胶囊表面特性。GC-MS分析2种产品的热稳定性表明,经二次包埋法制得的微胶囊,高温处理下(200℃,3 min)能够提供葱油香精最大程度的保护。     

高效装载的水溶性薄荷醇微胶囊的制备研究

以麦芽糊精和麦芽糖作为壁材、以变性淀粉为乳化剂将薄荷醇封存于稳定的玻璃态结构中,采用喷雾干燥法制备了薄荷醇微胶囊。利用原子力显微镜对其形貌进行表征发现薄荷醇微胶囊呈球形,大小在1～3μm之间,动态光散射法测量出微胶囊的平均粒径为1．75μm。分光光度法对微胶囊的总薄荷醇含量和表面薄荷醇含量进行定量研究,结果表明制备的薄荷醇微胶囊具有高的保留率、包埋率和微胶囊化效率。微胶囊化薄荷醇的水溶性好、稳定性强,使它可以广泛应用于食品、饮料、烟草、保健药品中。     

响应面法优化葱油香精微胶囊制备工艺的研究

文章以明胶、阿拉伯胶为壁材,采用复合凝聚法对葱油香精进行包埋,以微胶囊包埋率为评价指标,采用响应面分析法优化了影响包埋率的主要因素:壁材浓度、芯壁比和pH值。研究发现,复凝聚法制备葱油香精微胶囊的最佳工艺参数为:壁材浓度为1.82%、芯壁比1∶1.87、pH 4.16。在此基础上,采用喷雾干燥法可以制备出葱油香精微胶囊白色粉状产品,微胶囊粒径大小较为均一,体积平均粒径为65.54μm。     

响应面优化鸭肉香精微胶囊化制备工艺的研究

以明胶、阿拉伯胶作壁材,利用复凝聚法对鸭肉香精进行包埋,以包埋率为响应值,运用响应面分析法优化影响包埋率的主要因素:壁材浓度、芯壁比和pH。研究发现,复凝聚法制备鸭肉香精微胶囊的最佳工艺参数为:在壁材浓度为2.23%,芯壁比为1.19,pH为4.32的条件下,鸭肉香精微胶囊化包埋率最大值为81.61%,与理论值基本相符。     

薄荷油的胶束增溶体系

从定性及定量两个方面对薄荷油的胶束增溶体系进行了研究.定量方面,作了有关温度变化对增溶量的影响,并绘制了不同条件下的三元相图;定性方面,利用紫外吸收光谱法,研究了薄荷油在胶束内的增溶环境.     

蛋白质定量检测方法的探讨

综述了凯氏定氮法、考马斯亮蓝法、双缩脲法、Folin-酚法、紫外吸收法、BCA法、近红外光谱技术、电泳法及数字图像法等主要的蛋白质定量检测方法,分别介绍了各方法的原理、特点及应用,说明了其优缺点和适用范围,并通过实例对各种蛋白质的检测方法进行了探讨。     

UV absorption property of bamboo

This article describes ultra violet (UV) light shielding behaviour of Australian grown bamboo (Phyllostachys pubescens). Optical reflectance showed that untreated bamboo plant has UV absorption properties. To reveal the origin of the UV absorption property, its chemical components were extracted using several polar and non-polar solvents. The extracts in most of the polar and non-polar solvents showed UV absorption property. Protic polar solvents showed better ability to extract UV absorbing chemicals than aprotic and non-polar solvents, except hexane. The chemical components of bamboo were analysed by FT-IR spectroscopy and the findings were correlated with the UV absorbance characteristics. The results confirmed that the UV absorption ability of bamboo originates from nothing but lignin. It is thus indicated that the conventional methods to manufacture bamboo fibres, such as complete degumming or viscose methods, that involve the removal of lignin, cannot retain the unique UV absorption property of bamboo plant in bamboo fibres.     

食物过敏原结构变化的光谱学研究进展

光谱学方法已广泛应用于研究食物过敏原结构的变化。常用的光谱学方法包括圆二色光谱、荧光光谱、傅里叶变换红外光谱、拉曼光谱、紫外吸收光谱等,其中圆二色光谱仅应用于澄清的稀溶液中,常研究过敏原二级、三级结构变化;傅里叶变换红外光谱不受过敏原相对分子质量大小、光散射以及荧光的影响,其酰胺Ⅰ带对于过敏原二级结构的研究最有价值;拉曼光谱采用光子探针,对微克级样品无损伤探测,适用于稀有、珍贵样品;荧光光谱多用于研究过敏原在变性过程中疏水性以及微环境变化;紫外吸收光谱在结构鉴定中需与其他光谱方法密切配合。前3种方法均可以确定过敏原二级结构的类型和相对含量,各方法的具体应用仍然值得进一步探索。     

Current methods to evaluate contribution and interactions of components to flavour of solid foods using hard cheese as an example

The flavours of hard cheeses are derived from the balance of odourants and tastants released during their consumption, but the identity, and balance, of these flavour-inducing compounds is still unknown for most cheeses. This can be attributed to the complexity of cheese composition and its analysis, of the processes occurring during consumption and the variations of human perception and expression of flavours. This review addresses some of the issues and methods being used to understand cheese flavour. It discusses factors which determine flavour release in the mouth, methods of preparation of extracts for analysis, sensory assessment of cheese flavour components and fractions, and of whole cheese, identification of odour active compounds and determination of their relative importance, temporal methods of analysis for flavour release and perception and methods of data analysis.     

Effect of UV‐C Disinfection of Beer — Sensory Analyses and Consumer Ranking

Ultraviolet (UV‐C) light irradiation is gaining rapid acceptance within the food and beverage industry as a non‐thermal disinfection technique. A series of trials, using a pilot scale UV‐C treatment system, were conducted to investigate the effect of UV‐C on beer with specific attention to lightstruck flavour formation. Both commercial and micro‐brewed beers were treated with UV‐C light at 254 nm. Samples were analysed by consumer and trained panels. Sensory analyses revealed that at a low UV‐C level, lightstruck flavour was apparent and this increasingly gave way to a more intense burnt rubber off‐flavour as the UV‐C exposure was increased. A sample enrichment probe technique coupled with a gas chromatography‐mass spectrometry (SEP/GCMS) revealed the presence of lightstruck flavour in all the treated beers.     

THE INSTITUTE OF BREWING ANALYSIS COMMITTEE DETERMINATION OF IRON AND COPPER IN BEER BY ATOMIC ABSORPTION SPECTROSCOPY

Methods for the determination of iron and copper in beer by atomic absorption spectroscopy are recommended on the basis of collaborative studies. The methods have better reproducibilities than the colorimetric methods currently recommended.     

Measurement of interactions between polysaccharides and flavour compounds by exclusion size chromatography: Advantages and limits

Interactions between flavour compounds and polysaccharides have been studied by exclusion size chromatography, the Hummel and Dreyer method. Hydrogen bonding was found between 2-acetyl thia-zole and dextrines of different degrees of polymerisation. The number of binding sites and the affinity constant increase by increasing the degree of polymerisation. Hydrogen bonding was also responsible for the interactions between xanthane and 1-octen-3-ol or 2-acetyl pyra-zine, with 1 mole of 1-octen-3-ol bound per pentasaccharide repeating unit. Unfortunately, the number of flavour compounds, which can be studied with this method, is limited due to their low water solubility and their low UV absorption.     

尿素对经动态高压微射流(DHPM)诱导去折叠胰蛋白酶构象变化的影响

以牛胰蛋白酶为原料,通过紫外吸收光谱、荧光发射光谱和圆二色谱研究尿素对天然胰蛋白酶和经动态高压微射流(DHPM)诱导去折叠胰蛋白酶的构象变化。结果显示：天然胰蛋白酶构象在尿素浓度4.0～6.0mol/L之间变化最显著,紫外吸光度从0.2746降至0.1824,吸收峰从波长279nm红移至283nm,相对荧光强度从105.9降至98.27,发射峰从波长352nm红移至355nm,β-折叠含量从46.9%降至30.6%;而去折叠胰蛋白酶构象在尿素浓度2.0～4.0mol/L之间变化最显著,紫外吸光度从0.3121降至0.2159,吸收峰从波长281nm红移至283nm,相对荧光强度从108.24降至99.07,发射峰从波长353nm红移至360nm,β-折叠含量从40.6%降至38.9%。表明尿素对经DHPM处理后处于部分去折叠胰蛋白酶构象的影响更为显著。不同浓度尿素导致胰蛋白酶产生不同构象的中间体,表现出“熔球态”模型特征。     

绿原酸分析测定方法研究新进展

为了更准确地检测绿原酸的含量,对绿原酸含量分析的测定方法进行了综述。目前的检测方法主要有:紫外分光光度法、二阶导数光谱法、可见分光光度法、阻抑-催化褪色光度法、差示导数光谱法、二阶导数差示脉冲极谱定量分析法、胶束薄层色谱法、流动注射化学发光分析法、毛细管区带电泳法、薄层色谱扫描法(TLC法)、高效液相色谱法(HPLC法)、反相高效液相色谱法(RP-HPLC法)、系数倍率法、导数极谱法和HPLC法与其它方法的联用等,同时对绿原酸的检测方法进展进行了展望。