甜菜红色素的稳定性探讨

采用紫外可见光谱法对甜菜红色素的稳定性进行研究,探讨了pH、温度、时间和金属离子对甜菜红色素吸收光谱的影响,分析了甜菜红色素降解的原因。结果表明:甜菜红色素的稳定性较差,随着pH的增加、温度的升高、时间的延长,甜菜红色素的降解程度均逐渐增大。     

红叶甜菜红色素降解动力学研究

研究了光照、pH、温度对色素降解特性的影响。研究表明红叶甜菜红色素稳定性受pH、温度、光的影响,光照强度越大红叶甜菜红色素保存率越低,在pH2~6范围内色素较稳定,统计分析发现pH2、pH4和pH6色素保存率在实验温度下无显著差异;红叶甜菜红色素的热降解遵循Arrhenius定律,遵循一级降解动力学方程,随温度升高半衰期缩短,pH2、pH4和pH6的活化能分别为67.02kJ/mol、67.12kJ/mol和67.76kJ/mol,pH2、pH4和pH6的色素溶液在对应温度下的半衰期和活化能无显著差异。     

红曲红色素稳定性研究及光热降解动力学分析

红曲红色素是一种在食品行业应用广泛的天然色素。本文研究了pH、光照和温度对红曲红色素稳定性的影响,并建立光热降解动力学方程。结果表明,当溶液的pH5或pH9时,红色素稳定性降低,且pH升高至13时其溶液颜色由红色变为黄。红曲红色素的光稳定性较差,随着光照时间的增加,色素保存率不断下降,经过6h的照射后,色素保存率降至77.4%。通过对数据进行零级、一级和二级线性动力学方程的拟合,发现红曲红色素光降解更符合二级动力学。温度对红曲红色素稳定性影响较大,随着温度的升高,红曲红热降解速率不断加快,热降解符合一级动力学方程,降解反应活化能Ea仅为43.5k J·mol~(-1)。     

甜菜红色素提取工艺及其稳定性研究

目的:优化出甜菜红色素的提取工艺,并对甜菜红色素的稳定性进行研究。方法:首先研究影响提取甜菜红色素的几个因素,包括最佳提取液、料液比、提取时间、提取温度、提取p H,并通过正交试验设计与分析优化最佳工艺参数;然后研究了甜菜红色素在光照、温度、护色剂和各金属离子下的稳定性。结果:甜菜红色素提取的最佳工艺条件:在常温下,以水作为提取溶剂、提取料液比为1∶5(g/m L),时间为5h,p H为4.5,并进行二次提取;其中溶剂p H是影响提取效果的主要因素。甜菜红色素的稳定性研究结果表明:光照和温度对甜菜红色素稳定性影响较大;护色剂苯甲酸钠对甜菜红色素有保护作用,1‰苯甲酸钠护色效果最好。各金属离子对甜菜红色素色泽无明显影响,Ca2+对甜菜红色素稳定性影响最小、Fe3+和Cu2+对色素稳定性影响最大,同时Fe3+和Cu2+还可降低甜菜红色素的色调。结论:利用该工艺提取甜菜红色素简单可行,光照和温度对其稳定性影响较大,金属离子影响较小,此研究可为甜菜红分离提取提供理论指导和参考依据。     

甜菜红在双蛋白纤维上的吸附性能

采用甜菜红色素对双蛋白纤维进行染色,探讨染色温度、时间、pH值、氯化钠和染料用量对双蛋白纤维的染色性能的影响,分析甜菜红色素对双蛋白纤维的染色热力学,测试染色织物的色牢度。甜菜红色素对双蛋白纤维的优化染色工艺为:甜菜红1.5%,pH=2~3,染色温度30℃,染色时间90 min;甜菜红色素在双蛋白纤维上的吸附符合Langmuir吸附模型。     

响应面优化超声辅助提取甜菜红色素及稳定性研究

为了充分合理利用甜菜红色素资源,采用响应面优化了超声辅助提取甜菜红色素的工艺条件并对甜菜红色素的稳定性进行研究。响应面建立的模型数据拟合效果很好(R2=0.9401,Pr=0.001),优化所得最佳提取工艺参数为:超声时间55min、料液比1∶4.1g/m L、超声温度53℃、p H 4.4。甜菜红色素的稳定性研究结果表明:甜菜红色素应避光保存,Ca2+、Na+、Al3+、Mg2+等金属离子对甜菜红色素的稳定性影响微小,Fe3+和Cu2+严重影响甜菜红色素的稳定性,甜菜红色素适宜保存的p H范围为3~7,常用食品添加剂对甜菜红色素稳定性基本无影响。     

红心火龙果酒颜色稳定性影响因素的研究

为探索红心火龙果酒颜色稳定性的影响因素,进而确定其最佳贮藏条件,以自酿红心火龙果酒为试验对象,研究温度、光照、pH值和氮气对果酒颜色稳定性和口感的影响。研究表明：环境温度越高,红心火龙果酒颜色褪色越快,同时果酒口感也变差。光照能加速分解火龙果酒中的甜菜红色素,随着光照时间的延长,果酒的酒味变淡,酒性不协调。不同的pH值对红心火龙果酒的颜色和口感有显著的影响,在不影响口感的前提下,火龙果酒中甜菜红色素在pH 4时较稳定。充氮气可减缓色素降解,接触空气会加速色素的降解。红心火龙果酒的贮藏过程中应注意冷藏避光,在适宜的pH值下密封储存,且可适量填充氮气。     

甜菜红色素的稳定性及其在食品中的应用研究

本文研究了甜菜红色素的稳定性以及在食品中的应用。研究发现，甜菜红色素在80℃以下稳定；在pH呈酸性条件下之间稳定；在紫外光和室内光线下，随着时间的变化对色素有一定的影响；Cu^2＋，Fe2＋对色素的吸光度有一定的影响。维生素C对色素的影响是：随着用量的增加对色素的影响增大；甜菜红色素对还原剂和防腐剂稳定，对氧化剂不稳定。甜菜红色素在食品中的应用情况良好。     

红甜菜萃取液蒸发浓缩过程研究(I)红甜菜萃取液蒸发浓缩动力学

对红甜菜萃取液的蒸发浓缩动力学作了研究。表明甜菜红色素损失速率为表观二级反应,温度的影响遵循Arrhenius方程,建立了甜菜红色素降解速率与料液温度、料液相对密度、抗坏血酸浓度相关联的蒸发浓缩动力学模型。新型异形竖板降膜蒸发器中蒸发浓缩过程中甜菜红色素吸光度实测值与动力学理论模型的吸光度预测值吻合良好,表明动力学模型对预测工业蒸发器浓缩过程中甜菜红色素损失程度具有良好的准确性;可用于指导工业生产。     

响应面优化微波辅助提取甜菜红色素及其稳定性研究

通过单因素试验对甜菜红色素提取条件(料液比、温度、提取时间、提取液p H、提取溶剂等)进行初步探究,并通过微波辅助对色素提取进行响应面优化设计,结果表明影响提取最显著的因素是微波时间,其次是微波功率,最后是料液比。最适提取条件:料液比1∶5.76(g/m L),微波功率398 W,微波时间112.8 s,此条件甜菜红色素最大吸光度值为0.711 4。对提取的甜菜红色素进行超滤处理并对其粗提液进行稳定性研究,结果表明光照、p H对其稳定性影响显著,添加不同稳定剂对甜菜红色素稳定性有一定改善,苯甲酸钠(0.04%)和VC(0.04%)复配使用对于提高其稳定性作用较为明显。     

红叶甜菜红色素的稳定性研究

采用80% 乙醇为提取溶剂,将提取的色素液在230～700nm 范围内进行紫外扫描,而后分别探讨碳水化合物、pH 值、温度、氧化剂还原剂、光照、金属离子对色素在紫外和可见光区的稳定性的影响。结果表明：该色素在紫外光区有两个吸收峰,波长分别为270、334nm,可见光区有两个吸收峰,波长分别为538、666nm;红叶甜菜红色素对热比较稳定,但不耐高温;pH 值对色素颜色影响不是很大,除pH10 以外;碳水化合物对其影响不显著;其抗氧化能化较弱;自然光照射一定时间会褪色;大多数金属离子对其无影响;而Fe3+ 等少数金属离子对色素有影响。     

红甜菜萃取液蒸发浓缩过程研究(Ⅰ)红甜菜萃取液蒸发浓缩动力学

对红甜菜萃取液的蒸发浓缩动力学作了研究,表明甜菜红色素损失速率为表观二级反应,温度的影响遵循Arrhenius 方程,建立了甜菜红色素降解速率与料液温度、料液相对密度、抗坏血酸浓度相关联的蒸发浓缩动力学模型。新型异形竖板降膜蒸发器中蒸发浓缩过程中甜菜红色素吸光度实测值与动力学理论模型的吸光度预测值吻合良好,表明动力学模型对预测工业蒸发器浓缩过程中甜菜红色素损失程度具有良好的准确性,可用于指导工业生产。     

红甜菜色素稳定性影响因素研究进展

红甜菜是一种营养价值较高的食用蔬菜,含有大量的红甜菜色素。红甜菜色素是一种水溶性、含氮的季胺型生物碱,核心结构为甜菜醛氨酸。红甜菜色素依据化学结构不同可分为两类:甜菜红素和甜菜黄素。红甜菜色素作为一种食用天然色素,已应用于多种食品,但由于稳定性较差,其在食品、营养保健品和化妆品等领域的潜在应用受到诸多限制。作者综述了红甜菜色素的组成及结构,详细阐述了pH值、光照、温度、氧气和降解酶对红甜菜色素质量分数和颜色的影响,同时阐明了甜菜红素受这些因素影响后在易降解位置发生脱糖基化、脱羧、脱氢、醛亚胺键水解和异构化等化学变化的途径及产物,为深入研究甜菜色素稳定性、扩大红甜菜及红甜菜色素的应用领域提供参考。     

Functional Properties of a Food Colorant Prepared from Red Cabbage

Spectral, colorant, and stability properties of colorants based on red cabbage, grape, cranberry, beet, and Red No. 40 were compared in buffer and in a simulated beverage. At pH 3, red cabbage imparted a red color similar to that of beet juice and less orange than that of the other colorants. Increasing the pH of red cabbage extracts to 4 produced a bathochromic shift and decreased color strength. Tristimulus parameters displayed maxima when L was varied. Red cabbage pigments were more stable during heating and storage than were the other colorants tested. pH had little effect on color stability; exposure to light greatly increased color loss during storage.     

Red beet pigments as soft drink colorants

Red beet pigments were used, in the form of industrially produced concentrate, as a soft drink colorant instead of food dyestuffs. On the basis of sensoric analysis, optimal composition of fruit type soft drink was suggested. Beet concentrate in the concentration used (2.5 g per 100 g of drink) did influence neither taste nor flavour of drink. Decomposition of red pigments — betacyanins — follows the first order kinetics. Factors influencing colour stability, such as pH value, temperature, light, ascorbic acid concentration and flavour components, are discussed.     

果胶酶澄清火焰菜果醋的研究

以透光率为考察指标,采用单因素试验和正交试验研究了果胶酶澄清火焰菜果醋的最适工艺参数。试验结果表明,火焰菜果醋的最适澄清工艺条件为果胶酶添加量0.08mL/L、酶解时间90min、酶解温度38℃、酶解pH 3.5,在此条件下果醋的透光率达到了94.79%。澄清处理后的果醋清澈透明、口味清新、品质上佳。     

Characterisation of anthocyanin–betalain mixtures for food colouring by chromatic and HPLC-DAD-MS analyses

Anthocyanins and betalains that are mutually exclusive in nature were mixed to investigate their potential synergism for food colouring purposes. The blends obtained from four commercial anthocyanic (black carrot, elderberry, sour cherry and strawberry) and one betalainic extract (red beet) were studied with respect to colour evolution over three weeks. While new colour shades were produced by blending anthocyanins with betalains, chroma and hue angle of the mixtures changed over time. The greatest number of new colour shades with acceptable chroma was obtained at pH 4.5 and 5, the stability maxima of red beet, succeeded by pH 3.0. Interestingly, at pH 3.5 only one combination yielded an acceptable chroma, whereas at pH 7 no mixture was stable. To determine individual anthocyanins and betalains in mixtures in a single run, a HPLC method was developed and combined with a mass spectrometer for the identification of specific pseudomolecular and daughter ions.     

The effect of iron, tin, aluminium, and chromium on fading, discoloration, and precipitation in berry and red beet juices.

The effect of iron(II), tin(II), aluminium(III), and chromium(III) on the properties of red whortleberry, blackcurrant, and red beet juices was followed during storage for 10 months at 5 degrees C. The colour and pH changes were studied, and the precipitates formed were weighed and their metal contents assayed. Of the metals tested, only tin caused bluish discoloration in the berry juices. In the case of iron, aluminium, and chromium the low pH prevented this type of discoloration. In berry juices, some increases in colour intensity took place with the lowering of pH value, whereas in red beet juice the opposite change occurred. The colour changes due to storage appear to take place irrespective of the metals. Precipitation is enhanced in red whortleberry juice only by tin, and in blackcurrant juice by tin and iron. In red beet juice, precipitation is increased by the lowering of pH resulting from metal salt addition. In general, increase in the amount of metal added increased the metal content of the precipitate. Iron showed the greatest tendency to become bound in the precipitate, particularly in blackcurrant and red beet juice. The suitabilities of the metals for canning purposes are considered. Chromium, in particular, has interesting possibilities in view of the low degree of colour change associated with it.     

Value addition of red beet (Beta vulgaris L.) by-products: Emulsion formation and stability

Replacement of synthetically derived food additives and increase of sustainability are two major trends within the food industry, and usage of by-products may represent a potential solution. We characterised an extract obtained from red beet that could also be obtained from red beet peels, that are typical industrial by-products, and examined its interfacial and emulsion forming properties. Results showed that red beet extract contained considerable amounts of surface-active saponins. The smallest negatively charged droplets (~1.36 μm, −40 mV) were obtained at low emulsifier-to-oil ratio and were fairly stable over a wide range of environmental stresses such as a wide pH range and temperature (<50 °C) despite some oiling-off. Emulsions showed flocculation at low pH, as well as coalescence at high temperature (≥50 °C) and phase separation after a freeze–thaw cycle. Overall, our results indicate red beet extract may be employed as new naturally derived emulsifier for food and beverage products.