Carotenoids as food colorants

The carotenoids are a chemically related group of pigments which occur widely and abundantly in nature. Fruits, vegetables and vegetable oils, dairy products, leaves, shrimp, lobster, the plumage of exotic birds, all contain carotenoids. Chemically, the carotenoids may be divided into carotenes, made up of carbon and hydrogen only, and oxycarotenoids containing oxygen in addition to carbon and hydrogen. The use of carotenoid‐containing plant extracts for coloring foods has been practiced for centuries and continues today. Advances in chemical synthesis resulted in the complete laboratory synthesis of beta carotene in 1950. Since then the commercial synthesis of several carotenoids has been accomplished. In the U.S. three of these commercially synthesized carotenoids, beta‐carotene, beta‐apo‐8'‐carotenal, and canthaxanthin, are accepted color additives for use in foods and are exempt from certification. These three carotenoids are also widely accepted for food use in other countries. This paper deals with the chemistry and synthesis of these three carotenoids, with special emphasis on their numerous commercially available market forms and their characteristics, and on the application of these carotenoids in the coloring of food products.     

Eco-benign fungal colorants: sources and applications in textiles

Abstract

Color plays a pivotal role in textile industry with wide usage of varieties of chemical entities. Synthetic dyes and colorants are being used extensively in the present textile and dyeing industrial scenarios. Extensive use of synthetic dyes in textile industries has many drawbacks and constitutes environmental concern. In the recent years there has been an intensive research for the practical application of natural colorants on textiles as a feasible alternative to synthetic dyes. The aim of this review is to discuss the variety of characteristic colorants produced by fungi and to enlist its possible applications in textiles.     

Chemical studies of anthocyanins: A review

Anthocyanins are natural colorants which have raised a growing interest due to their extensive range of colours, innocuous and beneficial health effects. Despite the great potential of application that anthocyanins represent for food, pharmaceutical and cosmetic industries, their use has been limited because of their relative instability and low extraction percentages. Currently, most investigations on anthocyanins are focused on solving these problems, as well as their purification and identification.     

低聚木糖液色素的初步研究

应用凝胶过滤色谱和紫外光谱研究了低聚木糖生产原料和生产过程中形成的色素。研究结果表明,低聚木糖粗产品中主要存在三类色素,第一类是黑色素,来自玉米芯原料;第二类是焦糖色素,主要来自蒸煮过程;第三类是糖类物质的酸降解产物,产生于玉米芯的稀酸预处理和蒸煮过程。活性炭对上述三类色素均有一定的去除效果,但对相对分子质量为5000的黑色素的去除效果较差。阴离子交换树脂D301-G对低聚木糖液色素的脱除非常有效,几乎能完全脱除低聚木糖液中的焦糖色素。     

Transformations of elderberry anthocyanins

Summary The influence of pH on structural transformations of elderberry concentrate anthocyanins and anthocyanin preparation isolated from elderberries was studied. The red coloured cationic form and colourless pseudobase occur in equilibrium in the pH range 1.0–4.5. The time interval necessary for equilibration depends on pH as well as on the reaction environment. Equilibrium constants pK = (2.73 ± 0.16) for elderberry concentrate and pK = (2.92 ± 0.07) for anthocyanin preparation were calculated from absorbance values after equilibration between the cationic form and pseudobase. Two anhydrobases with different positions of carbonyl group are formed in solution at pH values higher than 4.5 corresponding to absorption maxima at 430 nm and 530 nm. These anhydro-bases are very unstable and are subject to further structural transformations. The stability of anhydro-bases increases with increasing pH value and decreasing temperature. Half-life values of the anhydrobase and ionized anhydrobase decay in elderberry concentrate and anthocyanin preparation were calculated.

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Transformationen der Anthocyane aus Holunderbeeren

Zusammenfassung Der Einfluß des pH-Wertes auf die strukturellen Änderungen der Anthocyane im Holunderbeerenkonzentrat und im aus Holunderbeeren isolierten Anthocyanpräparat wurde untersucht. Bei pH-Werten 1,0–4,5 befinden sich die rote Kationenform und die farblose Pseudobase in Gleichgewicht. Das Zeitintervall, notwendig zur Erreichung des Gleichgewichtes, hängt sowohl vom pH-Wert als auch vom Reaktionsmilieu ab. Die Gleichgewichtskonstanten pK=(2,73 ± 0,16) für das Holunderbeerenkonzentrat und pK = (2,92 ± 0,07) für das Anthocyanpräparat wurden aus den Absorptionswerten nach Erreichung des Gleichgewichtes zwischen der Kationenform und der Pseudobase ausgewertet. Bei pH-Werten 4,5 und höher werden in der Lösung zwei Anhydrobasen mit der unterschiedlichen Position der Carbonylgruppe gebildet, dessen Absorptionsmaxima bei 430 und 530 nm liegen. Diese Anhydrobasen sind sehr labil und ihre Struktur wird weiter verändert. Die Stabilität der Anhydrobasen steigt mit steigendem pH-Wert und sinkender Temperatur. Die Halbzeitwerte des Zerfalls der Anhydrobasen und der ionisierten Anhydrobasen wurden berechnet.

     

Determination of color, pigment, and phenolic stability in yogurt systems colored with nonacylated anthocyanins from Berberis boliviana L. as compared to other natural/synthetic colorants

ABSTRACT:  Anthocyanins are of interest to the food industry because of their antioxidant power, attractive color, and stability in high acid foods. Powder from the Peruvian berry Berberis boliviana Lechler, rich in nonacylated anthocyanins (7% to 8% dry weight), was incorporated into yogurt samples containing 3 different fat levels. Color (CIE L , a , b , chroma, and hue angle), pigment (monomeric anthocyanin and polymeric color), and total phenolics were monitored over 8 wk of storage and compared to yogurt treatments containing purple carrot acylated anthocyanins, red beet betalaines, or FD&C Red nr 40. Anthocyanin profiles were analyzed by HPLC coupled to photodiode array and mass detectors. Color of yogurt containing B. boliviana anthocyanins at 20 mg cyanidin-3-glucoside (cy-3-glu) equivalents/100 g yogurt ( L *= 65, chroma = 14, and hue angle = 335°) was similar to commercial blueberry yogurt ( L *= 65, chroma = 10.5, and hue angle = 341°). High color, pigment, and phenolic stability were observed in yogurts colored with B. boliviana , independent of the fat matrix. Acylated anthocyanins from purple carrot extracts exhibited increased stability with higher fat content. Anthocyanin degradation followed 1st-order kinetics. Pigment half-lives were 125 and 104 d for nonacylated anthocyanins at 10 and 20 mg cy-3-glu equivalents/100 g yogurt and 550.2, 232.6, and 128.9 d for acylated anthocyanins at 20 mg of cy-3-glu equivalents/100 g of 4%, 2%, and 0% fat yogurt. Addition of B. boliviana whole berry powder to yogurt matrices produced an attractive, stable anthocyanin-rich product, eliminating the need for industrial colorant extraction.     

颜料制剂--纺织工业的新型着色剂

概述了用于纺织工业的颜料制剂,包括颜料的定义、发展历史、市场意义和应用领域。讨论了颜料制剂的化学结构及满足当前高质量要求的颜料制剂的主要特征。以DyStar纺织颜料公司的Impemn K和Impemn HF颜料制剂为实践基础展开讨论。     

Analytical method for Buddleja colorants in foods

Buddleja yellow colorant derived from Buddleja officinalis Maxim. has recently been approved for use as a new kind of natural colorant for food additives in China. In order to distinguish Buddleja yellow colorant from other yellow colorants, two known phenylpropanoid glycosides, acteoside (= verbascoside) and poliumoside, were isolated from the colorant as marker substances for Buddleja yellow colorant. Poliumoside has not been detected in B. officinalis Maxim. previously. These phenylpropanoid glycosides were not detected in the fruits of Gardenia jasminoides Ellis or in the stamens of the flowers of Crocus sativus L., which also contain crocetin derivatives as coloring components, using a photodiode array and mass chromatograms. Thus, an analytical HPLC method was developed to distinguish foods that have been colored with yellow colorants containing crocetin derivatives, using phenylpropanoid glycosides as markers.     

食用合成色素分析方法的研究进展

综述了近几年来国内外有关食用合成色素分析的研究状况,分析方法包括:分光光度法、微柱法、极谱法、高效液相色谱法等。     

花青素研究进展

文章根据国内外对花青素生理功能的研究报导归纳了花色苷的主要生理活性并就其成分分离和结构鉴定做了概括。     

花色苷生物活性的研究进展

花色苷是一种广逭存在的水溶性植物色素，是水果和花靓丽颜色（红、橙、蓝）的来源。本研究对花色素类的吸收和代谢，抗氧化、抗癌及其它生物活性进行了综述。     

The anthocyanins of sunflower

The extraction process of red pigments from the husks of a cultivar of sunflower has been studied. It has been shown that a fraction containing circa 80% of the starting pigments could be obtained by grinding. Best extractions were obtained with distilled water-organic solvent mixtures of intermediate polarity values. The extraction yields are strongly influenced by the pH and the solvent/powder ratio and reach the maximum after about 2 hr.
The experimental data showed that the greater part of the pigments, readily precipitable by acidification to pH 2.0, are bonded to a macromolecule, probably of protein nature, as confirmed by electrophoresis.     

Berry anthocyanins: isolation,identification and antioxidant activities

Anthocyanins from bilberry, blackcurrant and cowberry were isolated for antioxidant evaluation. Individual compounds were identified and quantified using HPLC and HPLC/ESI–MS techniques. Antioxidant and radical‐scavenging capacities of the isolates were studied in emulsified methyl linoleate and human low‐density lipoprotein (LDL) in vitro and in the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) test. The total anthocyanin contents in the phenolic extracts of bilberry, blackcurrant and cowberry were 6000, 2360 and 680 mg kg^?1 fresh weight respectively. There were four dominant compounds in blackcurrant (glucosides and rutinosides of cyanidin and delphinidin), three in cowberry (monoglycosides of cyanidin) and 15 in bilberry (monoglycosides of cyanidin, delphinidin, malvidin, peonidin and petunidin). Quantification as cyanidin‐3‐glucoside equivalents gave markedly lower results regarding the total anthocyanin concentration and the content of individual delphinidin and malvidin compounds compared with quantification based on corresponding standard compounds. Berry anthocyanins were highly active radical scavengers in the DPPH test and effective antioxidants in emulsion and human LDL. Copyright © 2003 Society of Chemical Industry     

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.     

Blueberry anthocyanins in health promotion: A metabolic overview

Diet has gained scientific community attention due to the crucial role in health maintenance, but also in disease treatment, and essential in disease prevention. Several food and food components, particularly phenolic rich foods, have been investigated as they present themselves as putative functional foods. In the past decades, obesity has reached epidemic proportions and consequently, metabolic syndrome (a set of disorders as impaired glucose tolerance, insulin resistance, abdominal obesity, dyslipidemia and high blood pressure, which increase the risk of cardiovascular disease and diabetes) incidence is increasing worldwide at an alarming rate and this phenolic rich foods, specially berries have been investigated to their potential beneficial effect in this disorders.In the present work the chemistry of blueberries (BB) (fruits of some Vaccinium species) was summarised as well as the knowledge about bioavailability and biokinetic of anthocyanins from blueberries with particular emphasis on its implications in metabolic disorders.     

天然色素花青素的微胶囊化研究

研究喷雾干燥法制备高包埋率微胶囊化花青素的壁材组成以及工艺条件,结果表明:花青素∶壁材为20%、麦芽糊精∶β-环状糊精为3∶1、阿拉伯胶比例为10.0%、喷雾干燥的进口温度120℃、出口温度80℃时,花青素的微胶囊化效果最好、包埋率高,而且花青素微胶囊化后,其稳定性有显著提高。     

雪糕中合成色素的测定

分别采用碱性硫酸铜和乙酸锌-亚铁氰化钾作为沉淀剂对雪糕样品进行预处理,并按照GB/T5009.35-2003第一法中的聚酰胺吸附法对样液中的色素进行提取,用高效液相色谱法进行合成色素含量的测定.结果表明,采用沉淀剂对样品进行预处理,可降低雪糕浆料的粘稠度,有利于色素的提取.对于四种常用合成色素柠檬黄、胭脂红、日落黄、亮蓝,以碱性硫酸铜作为沉淀剂,加标回收率为72.04%～82.64%,相对标准偏差为1.48%～3.50%;以乙酸锌-亚铁氰化钾作为沉淀剂,加标回收率为81.62%～95.73%,相对标准偏差为1.46%～3.19%.采用乙酸锌-亚铁氰化钾进行样品预处理的方法准确度和精密度良好,可作为高效液相色谱法测定雪糕中合成色素的样品预处理方法.     

红提葡萄采后贮藏过程中花色苷的动力学研究

通过研究红提葡萄花色苷在不同贮藏温度和热处理时间下的稳定性,建立了花色苷降解动力学模型,研究结果表明,红提葡萄花色苷对热处理不稳定,其降解符合一级动力学反应,活化能(Ea)为21.29kJ/mol,指前因子(k0)为145.24,降解速率随温度的增高逐渐增大,而半衰期随着温度的增高逐渐降低。经验证,该降解动力学模型准确有效,可用于红提葡萄贮藏温度的选择和预测不同温度下的贮藏期。      

Acylated anthocyanins in broccoli sprouts

Broccoli is a nutritious vegetable and a good source of vitamins and minerals. It also contains important antioxidant phytochemicals like β-carotene and α-tocopherol, indoles and isothiocyanates. On the other hand, edible sprouts are novel nutritive plant-derived foods, good source of flavonoids and other polyphenols (Moreno, Pérez-Balibrea, et al., 2006).     

欧洲越桔花色苷的研究概况

欧洲越桔花色苷是一种从欧洲越桔果实中提取的天然活性成分，其生理功效主要体现在对视力的改善作用和对血管的保护作用上。本文综述了其基本理化性质、生理功效、提取制备及安全毒理等。