Effects of Temperature,Time, and pH on the Stability of Anthocyanin Extracts: Prediction of Total Anthocyanin Content Using Nonlinear Models

In this study, different anthocyanin sources including grape skin, black carrot, and red cabbage were used to determine the effect of thermal treatment, different acidity levels, and time on the anthocyanin content and degradation. The total anthocyanin contents were modeled by neuro fuzzy inference system (ANFIS) and artificial neural network (ANN) models. The red cabbage anthocyanin stabilities were higher than others. The anthocyanins degraded more rapidly at higher temperatures. The anthocyanin contents of samples decreased with the increase of pH from 3 to 7. Comparison of the models showed that the ANFIS model performed better than the ANN model for the estimation of total anthocyanin content in all samples. The lowest root mean square error (0.0457) and highest R ² (0.9942) values were obtained for red cabbage and grape skin in the validation period with the ANFIS model, respectively. This study showed that both models can be utilized efficiently for the prediction of total anthocyanin content affected by temperature, time, and pH.     

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.     

紫甘蓝花色苷稳定性及热降解动力学研究

为有效控制紫甘蓝加工过程中花色苷的降解,研究了 pH、温度、光照、金属离子及外源添加物对花色苷稳定性的影响.实验表明,紫甘蓝花色苷稳定性受pH、温度和光照影响较大,pH2.0左右的花色苷5 h保存率仍有92.92％±0.69％、40℃下避光5 h花色苷保存率有70.50％±0.52％,花色苷稳定性较强;添加不同浓度的金...     

Light and heat sensitivity of red cabbage extract in soft drink model systems

Anthocyanins of red cabbage (Brassica oleracea L.) display colour over a larger range of pH-values than the majority of anthocyanins from other natural sources, being pink at pH 3, violet at pH 5 and blue at pH 7. Using reversed phase high-performance liquid chromatography with diode array detection, cyanidin was found to be the only anthocyanidin of red cabbage extract and, tentatively, identified as cyanidin-3,5-diglucoside and cyanidin-3-sophoroside-5-glucoside, the latter found in various acylated forms. The apparent quantum yield for photobleaching has been determined for red cabbage extract at 25°C in air-saturated McIlvaine buffer, using monochromatic light at each of the irradiation wavelengths, 313, 366, and 436 nm, in continuous photolysis experiments, in order to provide an objective measure for the sensitivity of this food colorant to ultraviolet and visible light. The quantum yield was found to depend on both pH and irradiation wavelength, ranging from 0.2×10⁻⁴ mol einstein⁻¹ for 436 nm light at pH 7.0 to 3.7×10⁻⁴ mol einstein⁻¹ for 366 nm light at pH 5.0. The thermal stability at pH 3.0 in McIlvaine buffer of four different anthocyanin extracts was compared and, for the temperature range investigated (25–80°C) the degree of stability was red cabbage>blackcurrant>grape skin>elderberry. The thermal stability of the same anthocyanin extracts was also compared for a non-carbonated soft drink medium of pH 3.0 yielding the same order of stability but with rates of degradation approximately twice as high as in buffer, which may indicate a detrimental effect of sugar and ascorbic acid. Due to the high thermal stability of red cabbage extract in solution, photobleaching will be the primary destabilising factor for red cabbage anthocyanin-coloured products in display.     

Effect of microwave heating on the near infrared spectra and on the prediction accuracy of chemical parameters in red grape homogenates

This study reports the effect of microwaving on the chemical composition [pH, total soluble solids (TSS), dry matter (DM) and total anthocyanins extraction], and the visible (VIS) and (NIR) spectra of red grape homogenates. It was observed that microwaving red grape homogenates prior to analysis improved the NIR calibrations for total anthocyanins (SECV: 0.21?C0.13 mg g^?1) and TSS (SECV: 0.89?C0.54 °Brix), however no improvements in the NIR calibrations for DM were observed. Microwaving red grape samples prior to NIR scanning also caused an increased in absorbance for samples heated for up to 3 min, particularly in those wavelengths associated with water (1400 nm and 1930 nm). The practical implication of this study is that microwaving of red grape samples prior to scanning did not improve the NIR calibration statistics for the most common chemical parameters measured in red grapes.     

Phenolic phytochemicals in cabbage inhibit amyloid β protein-induced neurotoxicity

The antioxidative and neuronal protective effects of red and white cabbages were investigated against amyloid β protein (Aβ)-induced cytotoxicity in neuron-like PC12 cells. Red cabbage phenolic phytochemicals showed higher antioxidative effect. In cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), red cabbage showed more protective effect on Aβ-induced neurotoxicity. Since oxidative stress causes membrane breakdown, the protective effect of cabbage phytochemicals was investigated by lactate dehydrogenase and trypan blue exclusion assays. Red cabbages showed more efficient cell protective effects among samples. The overall relative neuronal cell protection activity of red cabbages by three tests was much higher than white cabbages. The degree of neuronal cell protection was closely correlated with their phenolic contents and their antioxidative capacities. Moreover, anthocyanins in cabbage appeared to be the major contributors.     

紫甘蓝花色苷的热降解动力学研究

探讨在不同温度和pH条件下紫甘蓝花色苷的热稳定性和降解动力学。以80%乙醇浸提,D-101大孔吸附树脂分离纯化制备紫甘蓝花色苷,在50、60、70、80 ℃温度范围内,于不同pH(2.0~6.0)体系中测定不同时间点的花色苷含量,研究其热降解动力学参数和褐变指数。结果表明,紫甘蓝花色苷热稳定性和褐变反应受温度和pH的影响,且其降解速率与时间呈良好线性关系,符合一级动力学模型。随着温度的升高,不同pH下花色苷的半衰期t_1/2均呈下降趋势,最大值为83.51 h(50 ℃,pH3.0),最小值为4.43 h(80 ℃,pH6.0),且各pH(2.0~6.0)体系的活化能E_a依次为42.30、45.31、38.85、26.83、31.20 kJ/mol。此外,其褐变指数随热处理时间延长、温度升高及pH增大而增大。     

Analysis and metabolite profiling of glucosinolates,anthocyanins and free amino acids in inbred lines of green and red cabbage (Brassica oleracea L.)

We profiled and quantified glucosinolates (GSLs), anthocyanins and free amino acids in thirty-seven inbred lines green and red cabbage. Analysis of these distinct cabbages revealed the presence of 8 GSLs, 13 anthocyanins and 12 free amino acids. GSL contents were varied among the different lines of cabbage. The maximum levels of glucoraphanin (14.91 μmol/g DW) and glucobrassicin (12.37) were found in FX 1-28 and FX 1-32 lines, respectively. Total GSLs in red cabbage lines were 50% higher than those of green cabbage. Anthocyanin contents in red cabbage were ranged from 4.11 to 6.81 mg/g DW in FX 2-3 and FX 1-34 lines, respectively. Among the 13 anthocyanins, both cyanidin 3-(feruloyl) (sinapoyl)diglucoside-5-glucoside and cyanidin 3-(sinapoyl) (sinapoyl)diglucoside-5-glucoside levels were the highest amounts. The amounts of total free amino acids were ranged from 523.5 to 1308 mg/100 g fresh weight (FW) in green cabbage and 484.8 to 1271 in red cabbage, respectively. In red cabbage lines, 9.4% of the total free amino acids accounted essential amino acids such as valine, threonine, isoleucine, leucine and lysine. Thus, the amounts of GSLs, anthocyanins, and amino acids varied widely, and the variations in these compounds between the lines of cabbage were significant.     

新疆伊犁地区赤霞珠葡萄成熟过程中花色苷组成及含量变化研究

本实验以新疆伊犁产区的赤霞珠酿酒葡萄为原料,采用液相色谱-质谱(HPLC-MS)联用检测分析伊犁地区2016年整个生长发育过程中赤霞珠酿酒葡萄果实中花色苷组成和含量上的变化规律,从中分析不同类型的花色苷在葡萄果实成熟的不同阶段的比例变化。实验表明:在伊犁地区,葡萄果实中的花色苷主要以甲氧基化形式存在,甲氧基化花色苷占总花色苷的比例在葡萄的成熟发育过程中变化不大。3’5’-取代花色苷在两地区均是葡萄果实成熟发育过程中的主要花色苷类型,占花色苷总量的70%以上,当葡萄果皮中花色苷积累至最大值后,随花色苷总量的减少3’-取代花色苷占总花色苷的比例均降低;乙酰化花色苷和香豆酰化花色苷占总花色苷的比例在葡萄果实成熟发育过程中的变化不同。伊犁地区花色苷在葡萄生长发育过程中均有下降趋势,香豆酰化花色苷占总花色苷的比例在伊犁地区葡萄果实成熟发育过程中呈现无规律的变化。     

The effects of homogenisation method and freezing on the determination of quality parameters in red grape berries of Vitis vinifera

The effect of sample processing with three different blenders, sample freezing and storage time on the determination of berry quality parameters – total anthocyanins, total soluble solids (TSS), total phenolics (TP) and pH – in homogenates of red grape berries has been examined. Samples of Cabernet Sauvignon, Merlot and Shiraz from four regions of South Australia were homogenised using Ultra-Turrax, Waring or Retsch commercial blenders applied to fresh samples, and to samples held in frozen storage overnight or for 1, 3, 6 and 12 months. All samples were analysed immediately after homogenisation. The results showed that neither homogeniser type nor freezing had any significant effect on total anthocyanins or TSS. However, freezing had an effect on total anthocyanins concentrations in samples with higher colour. The homogeniser type had a significant effect on TP and pH for all varieties analysed together. Freezing had no significant effect on TP, but significant effect on pH, the value being greater in samples at the lower end of the pH range. Frozen storage time of up to 3 months had no significant effect on total anthocyanins, TSS or T P. Statistically significant differences were observed in the concentration of total anthocyanins in samples after 3 months of frozen storage.     

Anthocyanin Pigments: Comparison of Extract Stability

Stabilities of anthocyanins from Concord grapes, red cabbage, tradescantia and ajuga were studied. RP-HPLC analysis was used to characterize individual anthocyanins and spectrophotometric analysis for all pigments. Anthocyanins from tradescantia were much more stable than the other extracts. Such increased stability was attributed to its intrinsic nature.     

鲜切紫甘蓝中花青苷和硫代葡萄糖苷在贮藏过程中的变化

采用高效液相色谱和液相色谱-质谱联用技术,对紫甘蓝（Brassica oleracea L. ssp. capitata f. rubra）中花青苷、硫代葡萄糖苷（简称硫苷）成分和含量进行鉴定和分析,并对低温（8±1）℃条件下经鲜切处理的紫甘蓝中花青苷和硫苷在货架期内（7 d）的变化情况进行研究。结果表明：紫甘蓝中存在11 种不同矢车菊花青苷,矢车菊-3-阿魏酰-槐糖苷-5-葡萄糖苷作为紫甘蓝中最主要的花青苷,在贮藏过程中的损失量占总花青苷损失量的55.51%,其占总量比例也在贮藏7 d后由35.12%下降至30.60%;紫甘蓝中存在10 种硫苷（由6 种脂肪族硫苷、3 种吲哚族硫苷和1 种芳香族硫苷组成）,以4-戊烯基硫苷和3-丁烯基硫苷为主,贮藏7 d后,二者损失率均为7%左右,损失量相加却达总花青苷损失量的50.07%,而所占比例相加也由71.68%上升到74.33%。     

Stability and antioxidative properties of acylated anthocyanins in three cultivars of red cabbage (Brassica oleracea L. var. capitata L. f. rubra)

BACKGROUND: Red cabbage is rich in acylated anthocyanins. The aim of the experiment has been to determine the stability of anthocyanins in extracts of red cabbage cultivars and examine their antioxidative properties. The (high‐performance liquid chromatographic) HPLC profile of anthocyanins characteristic of each red cabbage cultivar has also been determined. RESULTS: We have used three red cabbage cultivars: cv. Koda, Haco POL and Kissendrup SWE. The HPLC assays enabled us to distinguish nine anthocyanin compounds, which were all classified as cyanidin derivatives. These compounds occurred in different proportions in the three culitvars of red cabbage. The differences were observed in the degradation index of anthocyanins in extracts from the red cabbage cultivars examined, both stored at + 2 °C and frozen. The highest trolox equivalent antioxidant capacity (TEAC) was attained for anthocyanins from cv. Haco POL red cabbage, whereas the lowest value was determined for cv. Koda. CONCLUSION: There were differences in the stability and antioxidative properties of anthocyanin compounds in red cabbage extracts among the cultivars evaluated (Koda, Haco POL and Kissendrup SWE). The highest stability and strongest antioxidative properties were assigned to anthocyanins in extracts from cv. Haco POL. The HPLC profiles imply differences in proportions of anthocyanin compounds present in the three red cabbage cultivars. Copyright © 2009 Society of Chemical Industry     

Myrosinase activity and total glucosinolate content of cruciferous vegetables,and some properties of cabbage myrosinase in Taiwan

The myrosinase activity and total glucosinolates of 10 different cruciferous vegetables and some properties of cabbage (Brassica oleracea L var capitata L) myrosinase were investigated. Radish, cabbage and broccoli showed higher myrosinase activity than other samples. No correlation (P > 0–05) was found between myrosinase activity and total glucosinolates of cruciferous vegetables tested. Myrosinase activity for white cabbage was higher than red cabbage. An optimal pH of myrosinase activity was observed at pH 8–0 for both white and red cabbages. The myrosinase extracted from cabbage was more stable in neutral or alkaline pH. The optimal temperature of myrosinase activity for both cabbages was about 60°C, but the myrosinase activity was destroyed after heating at 70°C for 30 min. The myrosinase activities of both white and red cabbages were activated by 10 mM and 5 mM ascorbic acid, respectively.     

Evolution of polyphenols in red wines from Vitis vinifera L. during aging in the bottle

The evolution of anthocyanins and pyranoanthocyanins (as measured by high-performance liquid chromatography) in young red wines from Vitis vinifera L. cv Tempranillo, Graciano and Cabernet Sauvignon (vintage 2000) from Navarra (Spain) was studied during 26 months of aging in the bottle. For the anthocyanin pigments of grape origin, a progressive decrease in their concentration, corresponding to first-order kinetics, was observed during this period. Independently of the anthocyanin structure studied, grape anthocyanins in Tempranillo wine presented twofold slower kinetics than those in Graciano and Cabernet Sauvignon wines, which exhibited a very similar disappearance rate. Acylated anthocyanins presented a slightly higher disappearance rate than the nonacylated ones, indicating the possible hydrolysis of the former into the latter forms. However, no distinction was observed in the kinetics of the different anthocyanidin forms (delphinidins, petunidins, peonidins and malvidins). These results indicate that during aging under nonoxidative conditions (bottle), the chemical reactivity of grape anthocyanins in wine is influenced by the grape variety, a factor that imposes over the stability associated with the chemical structure of each anthocyanin form. In relation to the evolution of pyranoanthocyanins, anthocyanin–pyruvic acid adducts presented a similar or lower disappearance rate than their corresponding anthocyanin precursors during the first months of aging in the bottle, while anthocyanin–vinylphenol and anthocyanin–vinylflavanol adducts did not exhibit significant variations during the whole period studied.     

甲基吡喃花色苷的制备优化及HPLC-MS/MS分析

以葡萄皮红色素提取物为原料,正交实验法研究花色苷在丙酮介质中反应合成甲基吡喃花色苷的最佳条件,探讨了反应物比例、底物浓度、温度、pH等因素对甲基吡喃花色苷生成量的影响,高效液相色谱（HPLC）监测反应过程,并利用高效液相色谱-二极管阵列检测-串联离子阱多级质谱（HPLC-DAD-EI-MS/MS）法对反应产物进行定性和定量分析。结果表明最佳反应条件是:反应物比例（葡萄皮红色素提取物mg∶丙酮mL）15∶1,葡萄皮红色素提取物浓度2.5mg/mL,反应pH3.0、温度45℃。高效液相色谱串联质谱结合多级质谱裂解分析表明,反应主要产物为甲基吡喃锦葵花色苷,反应第9d其得率为49.4%。经分离纯化后的甲基吡喃花色苷特征吸收峰在478nm,与原花色苷比较明显发生蓝移。实验结果为甲基吡喃花色苷的高效制备、功能与理化性质研究提供了一种经济有效的研究方法和物质基础。      

Enhanced Anthocyanin Extraction from Red Cabbage Using Pulsed Electric Field Processing

Abstract: This study was conducted to evaluate the effect of pulsed electric field (PEF) treatment on anthocyanin extraction from red cabbage using water as a solvent. Mashed cabbage was placed in a batch treatment chamber and subjected to PEF (2.5 kV/cm electric field strength; 15 μs pulse width and 50 pulses, specific energy 15.63 J/g). Extracted anthocyanin concentrations (16 to 889 μg/mL) were determined using HPLC. Heat and light stabilities of the control and PEF-treated samples, having approximately the same initial concentrations, were studied. PEF treatments enhanced total anthocyanin extraction in water from red cabbage by 2.15 times with a higher proportion of nonacylated forms than the control (P < 0.05). The heat and light stabilities of the PEF-treated samples and control samples were not significantly different (P > 0.05). Practical Application: An innovative pretreatment technology, pulsed electric field processing, enhanced total anthocyanin extraction in water from red cabbage by 2.15 times. Manufacturers of natural colors can use this technology to extract anthocyanins from red cabbage efficiently.     

Studies on stability of blue grape anthocyanins

The stability of grape anthocyanins in grape squash and juice is influenced by the nature of packaging materials and preservatives. In grape squash losses were 65–70% in glass bottles, 64–67% in paper-aluminium foil-polyethylene (PFP) laminate pouches, 77–81% in polypropylene (PP) pouches and 68–73% in metallized polyester-polyethylene (MPP) laminate pouches during 60 days storage at 15–35°C. After 60 days, loss of anthocyanins was lower in samples preserved with sorbate than with benzoate, but not after 120 or 180 days storage. Sugar increased losses of anthocyanins, which were more stable in isolated model systems of sugar and benzoate than in grape squash and juice. Anthocyanins were most stable in anhydrous systems, and their rate of degradation progressively increased with water activity.     

Quantitative Comparison of the Stability of Anthocyanins from Brassica oleracea and Tradescantia pallida in Non-Sugar Drink Model and Protein Model Systems

The Tradescantia pallida anthocyanins were about 29 times more stable in a nonsugar drink model system than red cabbage (Brassica oleracea) anthocyanins, and 15 times in a fish protein system. The degradation of the anthocyanins from both sources in a nonsugar drink model was logarithmic rather than linear. The mechanism for logarithmic relationship was assumed to be the difficulty of water molecules diffusion to the hydrophobic center formed by the acyl groups and the aglycone.     

遗传算法优化双水相法提取葡萄皮渣花色苷工艺及其组分分析

以葡萄皮渣为原料,采用双水相法提取其中的花色苷并鉴定花色苷组分。在单因素实验的基础上,通过遗传算法优化双水相法提取葡萄皮渣花色苷的工艺;利用高效液相色谱-质谱联用鉴定葡萄皮渣花色苷提取物中花色苷组分。结果表明：双水相法提取葡萄皮渣花色苷的最佳工艺为：乙醇体积分数40%、硫酸铵质量分数26%、pH3.0、料液比1：38 g/mL,在此条件下花色苷得率（3.05±0.07） mg/g。经鉴定发现葡萄皮渣花色苷提取物含有2种花色苷组分,分别为飞燕草-3-葡萄糖苷和矢车菊素-3-葡萄糖苷,其纯度分别为90.16%和92.41%。研究结果为天然花色苷提取提供一种新的提取方式,并为进一步开发花色苷功能性食品提供依据。