赖氨酸Amadori和Heyns化合物热裂解产物对烟草风味的影响研究

  目的  比较赖氨酸Amadori和Heyns化合物的热解产物及对其烟草风味的影响。  方法  以赖氨酸和葡萄糖或果糖为原料,以偏重亚硫酸钠为催化剂、甲醇和冰醋酸为溶剂,分别合成赖氨酸的Amadori和Heyns化合物,采用在线热裂解-气相色谱/质谱联用技术(Py-GC/MS)对比了2种化合物的热解产物差异,并通过感官评吸实验比较了二者对卷烟风味的影响。  结果  （1）赖氨酸Amadori和Heyns化合物热解均能产生醛酮类、呋喃类、吡啶类、吡嗪类及吡咯类香味物质,同一类别产物的相对含量有较大差异。（2）赖氨酸Heyns化合物热解得到的风味成分数量更多。（3）赖氨酸Amadori化合物和Heyns化合物对卷烟的主要作用为增香、增浓和降低刺激,并使烟气更加流畅顺滑,赖氨酸Heyns化合物增加了卷烟白肋烟特征。  结论  赖氨酸Amadori化合物和Heyns化合物的热解产物不同,对卷烟风味的影响存在差异。      

三种Amadori化合物的热解研究

采用离线裂解装置在不同温度点对三种Amadori化合物1-L-丙氨酸-1-脱氧-D-果糖(ADF)、1-L-缬氨酸-1-脱氧-D-果糖(VDF)、1-L-脯氨酸-1-脱氧-D-果糖(PDF)分别进行裂解试验,并采用GC/MS联用技术对其产物进行初步定性研究。结果表明三种Amadori化合物在不同温度下裂解产物不同,高温时裂解产物较多;热解产物主要为醛类、吡嗪类、呋喃、呋喃酮、吡唑、吡咯、吡喃酮等杂环化合物,部分产物结构可以直接反映出Amadori化合物中糖或氨基酸的结构,这些物质是食品及卷烟烟气中重要的致香成分。      

HPLC-MS/MS法同时测定烟草中22种Amadori化合物

为同时测定不同类型烟叶中的Amadori化合物,围绕12种无标样Amadori化合物,分别进行了美拉德反应合成实验,基于高分辨的高效液相色谱-四极杆飞行时间质谱联用仪(HPLC-Q-TOF-MS),通过精确分子量匹配及二级碎裂方式验证,准确定性了各反应体系中的Amadori化合物,确定了用于多反应监测(MRM)模式的定量及定性离子对。在前期建立的10种具有标样的Amadori化合物的外标绝对定量方法的基础上,对12种无标样Amadori化合物采用保留时间及结构较为近似的Amadori化合物标准品的标准曲线进行近似定量。结果表明:(1)连续进行6 d以上测试(共进样300针以上),14个Amadori化合物的日间精密度10%,5个Amadori化合物的日间精密度在10%～15%之间。(2)烤烟、香料烟和白肋烟样品分析结果表明,Amadori化合物总量分别占烟叶干质量的2.47%、1.70%和0.14%,且不同类型烟叶中各Amadori化合物的质量分数也存在较大差异。该方法可实现烟草中22种Amadori化合物的同时快速测定。     

烘焙条件对白肋烟重要致香成分的影响

选择适宜的烘焙温度、空气含湿量和终端含水率等配套参数,以不同烘焙条件处理白肋烟,测定了处理后白肋烟中脯氨酸-葡萄糖Amadori化合物和13种碱性香味成分的含量,结合白肋烟处理前后两类致香成分总量的变化和感官质量评吸结果确定了白肋烟最优工艺处理条件.结果表明:①经不同条件烘焙处理后,白肋烟样品脯氨酸-葡萄糖Amadori化合物的含量均有不同程度的增加,即烘焙处理有利于Amadori化合物的生成.②碱性香味成分的总量在低温(100℃)下随空气含湿量的增大而呈现下降趋势,在高温(140℃)下随空气含湿量的增大则呈现上升趋势.③感官评吸结果与白肋烟中Amadori化合物和碱性香味成分总量的实验测定结果一致,即,最佳工艺处理条件为:烘焙温度120℃,空气含湿量400 g/kg,终端含水率8％.该工艺处理条件下,白肋烟致香成分含量较高,香气质量明显改善.     

Amadori化合物检测方法的研究进展

Amadori化合物是羰基化合物和氨基化合物发生美拉德反应生成的一类关键中间产物,除其本身的化学意义外,其后续反应产物对食品的颜色、风味、营养性、安全性、抗氧化性等品质都具有重要的影响。目前已经报道的Amadori化合物定性定量检测方法主要适用于红参、烟草和极小部分食品品种。本文综述了Amadori化合物的形成机理及其定性定量的检测方法,为建立用于广泛或复杂的食品样品中Amadori化合物的检测方法奠定基础。     

造纸法再造烟叶氨基酸、Amadori化合物含量分析及工艺影响研究

氨基酸、Amadori化合物与造纸法再造烟叶感官品质密切相关,本文研究国内外代表性造纸法再造烟叶产品中氨基酸、Amadori化合物含量差异,并结合再造烟叶生产过程中氨基酸、Amadori化合物含量变化趋势分析,以指导国产造纸法再造烟叶工业控制。研究结果表明,国内外造纸法再造烟叶产品中氨基酸、Amadori化合物含量有较明显差异,国外产品中氨基酸含量最低,其总量分别仅为烟叶、国产产品均值的46.83%、73.52%,而Amadori化合物中Fru-Leu、Fru-Val、Fru-Ile、Fru-Tyr、Fru-Amb含量高于烟叶和国内产品。结合国产造纸法再造烟叶生产工艺分析,提取、净化过程中氨基酸、Amadori化合物分别损失66.32%、74.24%,但浓缩过程中氨基酸、Amadori化合物含量分别增加了48.05%、76.49%,原料中氨基酸、Amadori化合物产品转移率分别为51.87%、47.12%。因此国产造纸法再造烟叶产品氨基酸、Amadori化合物的调控应重点关注提取、浓缩过程控制。     

两种Amadori衍生物的合成及其热降解产物研究

文章以D-果糖、L-苯丙氨酸和L-酪氨酸为原料合成两种Amadori衍生物:PDFD(二-O-异亚丙基-2,3:4,5-β-D-吡喃果糖基苯丙氨酸酯)和TDFD(二-O-异亚丙基-2,3:4,5-β-D-吡喃果糖基酪氨酸酯),用氢谱(1H NMR)、碳谱(13C NMR)以及高分辨质谱(HRMS)表征了物质的结构。采用热重(TG-DTG)、差示扫描量热法(DSC)、热裂解-气质(Py-GC/MS)联用技术研究了两种物质的热特性和热降解产物。结果表明,PDFD和TDFD最大质量损失率T_p值分别是273.3和340.5℃;两种物质均热降解产生大量的挥发性香味物质,如2-丁酮、苯甲醛、2-乙酰基呋喃、糠醛等,而且TDFD所需热降解温度较高且热降解产物含有酚类物质。对两种物质的热降解机理研究表明,保护糖环上的羟基在一定程度上可抑制吡喃糖环的降解,而氨基酸部分的降解几乎不受影响。该研究提供了一类基于Amadori化合物的香味前体物质,且为调控Amadori化合物热降解产物提供新思路。     

利用UPLC-MS/MS研究高Amadori化合物番茄粉的制备工艺

对番茄粉中Amadori化合物的提取工艺进行了优化,通过单因素和正交试验,利用超高效液相色谱-三重四级杆质谱（UPLC-MS/MS）研究了水分活度、温度、时间、组氨酸添加量及抗氧化剂添加量对番茄粉中Amadori化合物生成量的影响。结果表明番茄粉中Amadori化合物的最佳提取条件：以水为溶剂超声提取10 min。高Amadori化合物番茄粉的最佳热处理工艺：水分活度0.44、加热温度54 ℃、加热时间4.2 h、组氨酸添加量2.8 mg/g、抗氧化剂添加量0.048 mg/g。在此热处理工艺条件下番茄粉中的Amadori化合物总质量分数达到152.59 mg/g,Fru-His质量分数为3.32 mg/g,明显高于其它番茄制品。     

不同生态区域烤烟Amadori化合物含量与烟叶品质的关系分析

为明确不同生态区域烤烟中Amadori化合物含量(质量分数)差异,选取8个不同香型风格烤烟生态区249份烟叶样品,分析了不同生态区域Amadori化合物含量及其相关性,以及与化学品质指标间的关系.结果表明:①8个香型风格烤烟生态区不同部位烟叶Amadori化合物总量整体表现为:上部叶>中部叶>下部叶,基本服从正态分布,...     

菠萝浓缩物为糖源的Amadori焦甜香型烟用香料制备

为了探讨水果糖源体系下Amadori香料在卷烟加香方面的应用,作者利用菠萝浓缩物作为糖源与不同氨基酸在有利于Amadori化合物合成的条件下反应,通过感官评吸选出了加香效果最好的菠萝浓缩物-脯基酸Amadori香料(Pine-Pro),制备了焦甜香型且具有典型果香的混合型烟用香料。同时用高效液相色谱和在线裂解GC-MS分析了葡萄糖-脯基酸模型体系下脯氨酸-Amadori单体(Fru-Pro)在反应过程中的变化规律及不同温度下的热裂解产物。结果表明:0~2 h Fru-Pro生成量与葡萄糖消耗量相当,8~24 h Fru-Pro合成速度逐渐降低但大于分解速度,24 h后其分解速度大于合成速度;整个过程中葡萄糖是限制反应物,与葡萄糖相比,脯氨酸的含量降低相对较缓。实验表明:Fru-Pro的裂解产物中含有多个有吡咯类、吡啶类、吡喃酮类、呋喃酮类、环戊烯酮、吡嗪类等成分,其中的许多成分具有焦甜香,可能是复合香料燃烧产生焦甜香的主要贡献成分。     

The Comparison of the Contents of Sugar,Amadori, and Heyns Compounds in Fresh and Black Garlic

Black garlic is produced through thermal processing and is used as a healthy food throughout the world. Compared with fresh garlic, there are obvious changes in the color, taste, and biological functions of black garlic. To analyze and explain these changes, the contents of water‐soluble sugars, fructan, and the key intermediate compounds (Heyns and Amadori) of the Maillard reaction in fresh raw garlic and black garlic were investigated, which were important to control and to evaluate the quality of black garlic. The results showed that the fructan contents in the black garlics were decreased by more than 84.6% compared with the fresh raw garlics, which translated into changes in the fructose and glucose contents. The water‐soluble sugar content was drastically increased by values ranging from 187.79% to 790.96%. Therefore, the taste of the black garlic became very sweet. The sucrose content in black garlic was almost equivalent to fresh garlic. The Amadori and Heyns compounds were analyzed by HPLC‐MS/MS in multiple reaction monitoring mode using the different characteristic fragment ions of Heyns and Amadori compounds. The total content of the 3 main Amadori and 3 Heyns compounds in black garlic ranged from 762.53 to 280.56 μg/g, which was 40 to 100‐fold higher than the values in fresh raw garlic. This result was significant proof that the Maillard reaction in black garlic mainly utilized fructose and glucose, with some amino acids.     

Chemistry of Amadori rearrangement products: Analysis,synthesis, kinetics,reactions, and spectroscopic properties

The chemistry of the key intermediate in the Maillard reaction, the Amadori rearrangement product, is reviewed covering the areas of synthesis, chromatographic analyses, chemical and spectroscopic methods of characterization, reactions, and kinetics. Synthetic strategies involving free and protected sugars are described in detail with specific synthetic procedures. GC‐ and HPLC‐based separations of Amadori products are discussed in relation to the type of columns employed and methods of detection. Applications of infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy for structural elucidation of Amadori products are also reviewed. In addition, mass spectrometry of free, protected, and protein‐bound Amadori products under different ionization conditions are presented. The mechanism of acid/base catalyzed thermal degradation reactions of Amadori compounds, as well as their kinetics of formation, are critically evaluated.     

STABILITY OF ANTHOCYANINS, PHENOLS AND FREE RADICAL SCAVENGING ACTIVITY THROUGH SUGAR ADDITION DURING FROZEN STORAGE OF BLACKBERRIES

Influence of sugar and mixtures of sugar on color retention of two varieties of blackberries, Thornfree and Cacanska bestrna, were investigated during storage at − 18C for 12 months. After harvest, blackberries were coated with sugars (sucrose, fructose and glucose) and different sugar (sucrose  +  fructose  +  glucose, fructose  +  glucose, fructose  +  sucrose) mixtures. Anthocynin content, total phenol content and free radical scavenging activity of prepared samples were evaluated. Ratio of fruit : sugar was 1:1. The highest anthocyanin retention was in blackberry samples with glucose addition and the lowest in samples with sucrose addition, in both cultivars. Blackberry samples with sucrose addition had even lower retention than samples without sugar addition. Samples with an addition of other sugars had higher retention of anthocyanin than samples stored without sugars.

PRACTICAL APPLICATION

Possibility of phenols retention of blackberries due to sugar addition, during cold storage was investigated. Results showed that glucose had the most positive effect on anthocyanins retention as well as total phenolic compounds content. For that reason, certain amount of sucrose in fruit preserves can be replaced by addition of glucose, and for that reason retention of phenolic compounds can be higher and, as could be expected, more effective against oxidative stress in human body due to intake of product formulation with glucose.     

Effects of sugars in growth media,diluents and enumeration media on survival and recovery of Saccharomyces cerevisiae heated in peach puree

Thermal resistance, injury and recovery of Saccharomyces cerevisiae heated in peach puree were studied. The effects of sucrose, glucose and fructose in puree and in recovery media were avaluated. In addition, the influence of sucrose in growth media and diluent on susceptibility to injury and extent of resuscitation were examined. Cells cultured in broth supplemented with sucrose had increased resistance to heat. The presence of sucrose, glucose and fructose in peach puree protected cells against thermal inactivation, whereas sucrose tended to be less inhibitory to stressed cells in enumeration media when compared to glucose and fructose. Repair of heat-stressed cells was retarded by holding cells in diluent containing sucrose and a reduced level of peach puree. These observations must be considered if pasteurization processes for peach products such as puree and concentrate are to be optimized. Results will also be of value to those selecting procedures for enumerating thermally injured yeast cells.     

碎米制备高果糖浆的工艺研究

研究碎米制备高果糖浆的工艺,主要对碎米葡萄糖异构化制取果葡糖液、钙型树脂分离果糖和葡萄糖获得高果糖浆的工艺进行优化。通过单因素和正交试验,得到制取果葡糖液的最优条件：异构酶加酶量9mg/g 碎米葡萄糖、pH7.5、反应温度70℃、反应时间35h;通过正交试验,得到树脂分离制取高果糖浆的最优条件：分离温度70℃、糖液体积分数20%、洗脱液流速4mL/min、进料量40mL。在优化条件下获取的高果糖浆果糖含量为89.64%。     

Metabolic transit of Amadori products.

In several studies, the absorption and urinary excretion of free and protein bound Amadori products were measured in rats and humans. Both, in vitro tests with everted intestinal sac preparations and in vivo experiments, showed that there is no active intestinal transport of these compounds but an absorption by diffusion. Trials with tissue slices have shown that there was an uptake into the cells of the liver, kidneys and muscles. Metabolism of Amadori products, if it exists in animals, tends to be very low. Micoorganisms in the large intestines decompose the Amadori products almost completely. The profile of urinary excretion of Amadori products after the ingestion of test meals showed a rapid elimination of the absorbed part, while the fecal output, although low because of the hind gut fermentation, persisted up to 3 days. Only 1-3% of the ingested amounts of protein bound Amadori products were recovered in the urine, which suggests a low absorption rate.     

Verhalten von Amadori-Verbindungen w?hrend der Kakaoverarbeitung 1. Bildung und Abbau von Amadori-Verbindungen

Zusammenfassung Es konnte nachgewiesen werden, daß sowohl in geröstetem als auch in ungeröstetem Kakao Amadori-Verbindungen vorkommen. Sie werden aus reduzierenden Zuckern (Aldosen) und Aminosäuren gebildet. Sie stellen Vorstufen der bei Röstprozessen ablaufenden und zur Aromabildung führenden Maillard-Reaktion dar. Amadori-Verbindungen treten zwar bereits bei der Aminosäureanalyse von Kakaoextrakten in Erscheinung, werden hier aber nur unvollständig getrennt und können daher nicht zugeordnet werden. Eine vollständige Auftrennung der in Kakao enthaltenen Amadori-Verbindungen war erst durch Capillargaschromatographie nach erfolgter Oximierung und Silylierung möglich. Es treten für jede der Einzelverbindungen Doppelpeaks auf, die der syn- und anti-Form der Oxime entsprechen. Die Untersuchungen ergaben, daß Amadori-Verbindungen bereits in fermentierten und im Erzeugerland getrockneten Kakaobohnen vorliegen. Ihre von den jeweiligen Mengen der freien Aminosäuren abhängigen Konzentrationen nehmen bei einer der Röstung vorgeschalteten Vortrocknung weiter zu. Im Verlauf der Röstung erfolgt anfangs eine gewisse Zunahme, später jedoch eine Abnahme. Auch während des bei der Schokoladenherstellung sich anschließenden Conchierprozesses werden Amadori-Verbindungen weiter abgebaut.

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The role of Amadori compounds during cocoa processing1. Formation and decomposition of Amadori compounds

Summary Amadori compounds formed by the reaction of reducing sugars (aldoses) and amino acids occur in both roasted and unroasted cocoa. They are precursors of the Maillard reaction leading to the formation of aroma compounds during the roasting processes. Amadori compounds appear during the amino acid analysis of cocoa extracts. However, they cannot be separated completely and therefore cannot be identified. Prior to gas chromatographic separation, the Amadori compounds isolated from cocoa were oximated and trimethylsilylized. By capillary gas chromatography double peaks for each compound corresponding to the syn- and anti-forms of the oximes were obtained. It was shown that Amadori compounds already occur in fermented cocoa beans dried in the producer country. Depending on the amounts of the individual free amino acids, their concentrations increase during pre-drying prior to roasting. Furthermore during the roasting process an increase in the amount of these compounds Was observed which was later followed by a decrease. Amadori compounds also decompose during the conching process performed during chocolate processing.