转化糖浆中5—羟甲基糠醛的形成

研究了转化糖浆生产过程中影响5－羟甲基糖醛（5－HMF）形成的因素,并通过正交试验和单因素试验,优化出蔗糖酸水解生产转化糖浆的较优工艺条件,即蔗糖水解液质量分数为72．7％,PH值2．0,温度80度,反应时间90min。在优化条件下每百克转化糖浆中5－HMF的含量为1．6mg,总还原糖的质量分数为78．2％。     

HPLC法测定牛乳中5-羟甲基糠醛的含量

采用HPLC法测定牛乳中5-HMF含量,5-HMF的回收率可达到91.7%。在不同加工工艺乳制品中,UHT低乳糖奶中5-HMF含量为4.733μg/mL,分别是巴氏杀菌奶和UHT保鲜奶的19倍和10倍。     

HPLC法测定牛乳中5-羟甲基糠醛的含量

采用HPLC法测定牛乳中5-HMF含量,5-HMF的回收率可达到91.7%。在不同加工工艺乳制品中,UHT低乳糖奶中5-HMF含量为4.733μg/mL,分别是巴氏杀菌奶和UHT保鲜奶的19倍和10倍。      

5-羟甲基糠醛在F-55果葡糖浆贮存过程中的变化研究

5-羟甲基糠醛(HMF)作为影响果葡糖浆风味的异味化合物之一,在贮存过程中的变化很可能直接影响到果葡糖浆制成品口感的好坏。研究了HMF在F-55果葡糖浆贮存过程中的变化情况,结果表明温度升高会导致HMF含量在40 d后达到最高峰。果葡糖浆在低温条件下贮存,且贮存期控制在40 d内,可减少HMF对糖浆质量的影响。     

HPLC法检测乳品中5-羟甲基糠醛和糠醛

建立了乳制品中5-羟甲基糠醛和糠醛的高效液相色谱分析方法。样品用沉淀剂沉淀过滤后,以水-甲醇溶液为流动相,C18反相色谱柱分离,紫外检测器280nm检测。结果表明,5-羟甲基糠醛和糠醛可以完全分离。在0.03~100.00mg/kg范围内,该方法呈良好的线性关系,回收率为83.3%~113.3%。本方法用于乳制品中5-羟甲基糠醛和糠醛的测定,操作简单、定量准确、重复性好。     

降低盐酸氨溴索葡萄糖注射液中杂质5-羟甲基糠醛含量

随着盐酸氨溴索葡萄糖注射液的不断普及和推广,其生产企业不断增加,其生产规模也不断扩大。这就给药品生产企业敲响了警钟,要不断地提高产品质量。文章是笔者在实际生产过程中摸索的控制盐酸氨溴索葡萄糖注射液中杂质5-羟甲基糠醛的方法,希望能够给广大同仁以启发。     

紫外分光光度法测定糖蜜中5-羟甲基糠醛含量

采用紫外分光光度法测定甘蔗糖蜜中5-羟甲基糠醛（5-HMF）含量,以5-羟甲基糠醛为标准品,在284nm波长处对糖蜜样品进行了定量分析。测定结果表明,回归方程为Y=0.02046+0.1145X,R=0.9995,线性范围0～15μg/mL,测定精密度RSD为1.27%,重现性良好。平均回收率为97.91%,回收率RSD为1.67%（n=6）,检出限为0.08μg/mL。      

熬糖工艺条件对糖膏中5-羟甲基糠醛和糠醛含量的影响

为严控糖果质量,尽量减少有害物质的产生,采用高效液相色谱系统地分析考察了不同工艺条件下熬制的硬质糖果半成品糖膏中5-羟甲基糠醛(5-HMF)和糠醛(FFA)的含量变化及其规律。结果表明,合适的熬糖温度应控制在120～132℃之间,熬糖时间控制在9-10 min;蔗糖与淀粉糖浆及水的比例为55:45:15较合适;熬糖原料应尽量选用高纯度的蔗糖和低葡萄糖含量的淀粉糖浆。抗坏血酸不宜作为熬糖抗氧化剂直接使用。     

紫外分光光度法测定糖蜜中5-羟甲基糠醛含量

采用紫外分光光度法测定甘蔗糖蜜中5-羟甲基糠醛(5-HMF)含量,以5-羟甲基糠醛为标准品,在284nm波长处对糖蜜样品进行了定量分析。测定结果表明,回归方程为Y=0.02046+0.1145X,R=0.9995,线性范围0～15μg/mL,测定精密度RSD为1.27%,重现性良好。平均回收率为97.91%,回收率RSD为1.67%(n=6),检出限为0.08μg/mL。     

食品中5-羟甲基糠醛的形成与控制

5-羟甲基糠醛(5-hydroxymethylfurfural,HMF)是食品热加工和贮藏过程中产生的内源性污染物,主要通过美拉德反应和己糖在酸性条件下脱水产生,其形成过程受反应底物种类、加热温度、反应体系p H、水分活度及金属离子等影响。HMF具有一定神经毒性、遗传毒性;摄入后在磺基转移酶作用下可转化为具有致癌毒性的羟甲基糠醛次硫酸,因而近年来HMF受到了国内外的广泛关注。本文综述了HMF形成的途径、影响因素和控制措施。     

提高转化糖浆质量的研究

转化糖浆的质量受多种因素的影响 ,通过实验 ,确定了制备转化糖浆的最佳工艺条件 ,经工厂生产使用 ,证明这些选择是可行的     

不同活性炭对果葡糖浆脱色性能及5-羟甲基糠醛吸附力的比较

5-羟甲基糠醛是影响果葡糖浆风味的异味物质之一,在果葡糖浆的生产工艺上无法完全去除,需要通过调节工艺参数得以控制。通过分析活性炭对5-羟甲基糠醛的吸附力及对糖浆的脱色效果,得出了不同工艺制造的粉状活性炭的优劣性,为果葡糖浆生产厂家活性炭的选择及添加比例提供参考。     

原糖溶液电解脱色的研究

阐述了原糖溶液电解脱色过程的机理,并对电解原糖浆脱色进行了实验研究,考察电解时间、电流密度、温度、锤度等因素对原糖浆脱色的影响。结果表明,电解对原糖溶液具有显著的脱色效果,对40築x的原糖溶液脱色率可以达到90%以上。     

红心与白心火龙果总糖、还原糖含量及其抗氧化活性的对比分析

以红心与白心火龙果为原料,采用热水浸提法提取果肉中的糖分。分析比较2种火龙果总糖、还原糖含量及其抗氧化活性。试验表明,温度对糖分提取具有显著影响。在80℃时,红心火龙果总糖(28.68%)及还原糖(8.85%)含量均显著高于白心火龙果总糖(18.46%)及还原糖(7.09%)含量。抗氧化活性测试结果显示,其抗氧化活性随多糖浓度的升高而增强,其中红心火龙果多糖的抗氧化活性强于白心火龙果。当多糖浓度为2.0 mg/mL时,红心火龙果多糖对·OH、DPPH、NO2-的清除率可达73.44%、48.39%、47.59%,总抗氧化力为0.79,总还原力为0.65。     

绵白糖微波干燥的参数关联图及其应用

在对绵白糖微波干燥描述的基础上，创立了一个干燥过程的因素关联图。关联图包含了绵白糖初始湿含量、干燥时间、出口温度和干燥的湿含量降这四个相互影响的因素。利用这一关联图，可以简捷地预测需要的干燥时间，绵白糖在出口的温度，或者预测在一定条件下的干燥效果。     

关于白砂糖电导灰分偏高的原因分析

分析灰分超标白砂糖灰分成份,并通过试验室模拟试验与分析主要灰分成份在澄清过程变化,探讨白砂糖灰分超标的主要原因,为糖厂降低白砂糖灰分提供理论依据。     

Standardisation of the detection of invert sugar addition to apple juice by capillary gas chromatography

 Capillary gas chromatography (CGC) can be used to check the authenticity of various fruit juices by analysing their oligosaccharide fingerprint profile. Thus, it enables the analyst to detect, for instance, the dilution of apple juice concentrates with cheaper sweeteners such as invert sugar syrup. In order to detect this, two marker peaks (IS1 and IS2) that are present in most invert sugar syrups are monitored in the CGC chromatogram of apple juice. In freshly pressed apple juice, these peaks are normally not found. As a result of apple juice processing and, in particular, the thermal treatment required to concentrate and pasteurise the juice, these peaks may however be present in authentic apple juice concentrate and juice made from it. It is nevertheless possible to distinguish between juice showing this "heat effect" and that to which invert sugar has been added since the IS2/IS1 peak ratio is very different in heated apple juice and in invert sugar syrups. Measuring this ratio and setting a maximum IS2/IS1 cut-off limit enables the analyst to assess whether the sample meets the set norms or has been adulterated. In the past, many laboratories experienced difficulties when comparing the results of this analysis and, in particular, IS2/IS1 peak ratios. We present evidence that this unsatisfactory situation is mainly due to the chromatographic behaviour of the IS1 peak. It appears indeed to be difficult to set up chromatographic conditions in all laboratories in order to produce reproducible results of the IS2/IS1 ratio. We have therefore examined the possibility of standardising results of this analysis and demonstrate that the comparison of any unknown apple juice sample with an external apple juice reference sample enables different laboratories to reach similar conclusions. The IS2/IS1 peak ratio in this reference sample was adjusted to the significant cut-off limit. The assessment (fail or pass) is thus based on a standardised IS2/IS1 ratio that is independent of several important analytical parameters which tend to strongly influence it. Received: 26 December 1997 / Revised version: 30 March 1998     

Standardisation of the detection of invert sugar addition to apple juice by capillary gas chromatography

 Capillary gas chromatography (CGC) can be used to check the authenticity of various fruit juices by analysing their oligosaccharide fingerprint profile. Thus, it enables the analyst to detect, for instance, the dilution of apple juice concentrates with cheaper sweeteners such as invert sugar syrup. In order to detect this, two marker peaks (IS1 and IS2) that are present in most invert sugar syrups are monitored in the CGC chromatogram of apple juice. In freshly pressed apple juice, these peaks are normally not found. As a result of apple juice processing and, in particular, the thermal treatment required to concentrate and pasteurise the juice, these peaks may however be present in authentic apple juice concentrate and juice made from it. It is nevertheless possible to distinguish between juice showing this "heat effect" and that to which invert sugar has been added since the IS2/IS1 peak ratio is very different in heated apple juice and in invert sugar syrups. Measuring this ratio and setting a maximum IS2/IS1 cut-off limit enables the analyst to assess whether the sample meets the set norms or has been adulterated. In the past, many laboratories experienced difficulties when comparing the results of this analysis and, in particular, IS2/IS1 peak ratios. We present evidence that this unsatisfactory situation is mainly due to the chromatographic behaviour of the IS1 peak. It appears indeed to be difficult to set up chromatographic conditions in all laboratories in order to produce reproducible results of the IS2/IS1 ratio. We have therefore examined the possibility of standardising results of this analysis and demonstrate that the comparison of any unknown apple juice sample with an external apple juice reference sample enables different laboratories to reach similar conclusions. The IS2/IS1 peak ratio in this reference sample was adjusted to the significant cut-off limit. The assessment (fail or pass) is thus based on a standardised IS2/IS1 ratio that is independent of several important analytical parameters which tend to strongly influence it. Received: 26 December 1997 / Revised version: 30 March 1998     

果葡糖浆在果汁饮料中的应用研究

对使用蔗糖与果葡糖浆生产的果汁饮料的成分进行了分析，比较了两类产品的糖成分和感官差异。结果表明：使用蔗糖生产的果汁饮料与使用果葡糖浆生产的果汁饮料比较，果葡糖浆对产品色泽的影响与蔗糖没有明显区别；但在产品风味方面，后者甜味消失快，果香味与酸味变浓；在果汁生产过程中，采用果葡糖浆部分替代蔗糖的产品风味不受影响．