Effect of pH on Lipid Oxidation and Anthocyanin Stability in Flaxseed Oil-in-Water Emulsions With Black Carrot Extract

IF 3.4 2区农林科学 Q2 FOOD SCIENCE & TECHNOLOGY

Journal of Food Science Pub Date : 2025-09-21 DOI:10.1111/1750-3841.70568

Evelyn Klinger, Hanna Salminen, Karola Bause, Jochen Weiss

{"title":"Effect of pH on Lipid Oxidation and Anthocyanin Stability in Flaxseed Oil-in-Water Emulsions With Black Carrot Extract","authors":"Evelyn Klinger, Hanna Salminen, Karola Bause, Jochen Weiss","doi":"10.1111/1750-3841.70568","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <p>The strong pH sensitivity and the activity toward free radical reactions limit the use of anthocyanins as food colorants in emulsion-based food applications. The aim of this study was to gain a comprehensive understanding of color stability of anthocyanin-rich black carrot extracts in ω-3 fatty acid–rich oil-in-water emulsions as a function of pH. The stability of the anthocyanins was influenced by the degree of lipid oxidation, which in turn depended on the pH value. The formation of lipid oxidation products was accelerated in emulsions without added black carrot extract, which is associated with the antioxidant activity of anthocyanins. Furthermore, lipid oxidation increased with decreasing pH due to a higher solubility of catalyzing metals like iron. The anthocyanins showed a pH-dependent degradation kinetics: pH 2 (<i>k</i> = 1.44 h<sup>−1</sup>) > pH 3 (<i>k</i> = 0.3 h<sup>−1</sup>) > pH 4 (<i>k</i> = 0.06 h<sup>−1</sup>) ≅ pH 6 (<i>k</i> = 0.09 h<sup>−1</sup>), which correlated with reduced concentrations of lipid oxidation products. This is contrary to the common behavior of anthocyanins in aqueous solutions, where their stability increases with decreasing pH. The best color stability of the black carrot extract in the oil-in-water emulsion was observed at pH 4 instead of pH 6, due to a pH-dependent deprotonation reaction. Gaining insights into the complex relationship between pH, lipid oxidation, and the color stability of anthocyanin-rich black carrot extracts in ω-3 fatty acid–rich emulsions challenges conventional understanding and offers valuable guidance for improving the use of anthocyanins as food colorants in emulsion-based applications.</p>\n </section>\n \n <section>\n \n <h3> Practical Applications</h3>\n \n <p>This study provides insight into the stability of anthocyanin-based natural colorants, such as black carrot extract, in oil-in-water emulsions, facilitating their application in lipid-containing food systems. It provides a more comprehensive understanding of the pH-dependent degradation mechanisms of anthocyanins, extending current knowledge from aqueous solutions to emulsion-based conditions.</p>\n </section>\n </div>","PeriodicalId":193,"journal":{"name":"Journal of Food Science","volume":"90 9","pages":""},"PeriodicalIF":3.4000,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ift.onlinelibrary.wiley.com/doi/epdf/10.1111/1750-3841.70568","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Food Science","FirstCategoryId":"97","ListUrlMain":"https://ift.onlinelibrary.wiley.com/doi/10.1111/1750-3841.70568","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"FOOD SCIENCE & TECHNOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

The strong pH sensitivity and the activity toward free radical reactions limit the use of anthocyanins as food colorants in emulsion-based food applications. The aim of this study was to gain a comprehensive understanding of color stability of anthocyanin-rich black carrot extracts in ω-3 fatty acid–rich oil-in-water emulsions as a function of pH. The stability of the anthocyanins was influenced by the degree of lipid oxidation, which in turn depended on the pH value. The formation of lipid oxidation products was accelerated in emulsions without added black carrot extract, which is associated with the antioxidant activity of anthocyanins. Furthermore, lipid oxidation increased with decreasing pH due to a higher solubility of catalyzing metals like iron. The anthocyanins showed a pH-dependent degradation kinetics: pH 2 (k = 1.44 h⁻¹) > pH 3 (k = 0.3 h⁻¹) > pH 4 (k = 0.06 h⁻¹) ≅ pH 6 (k = 0.09 h⁻¹), which correlated with reduced concentrations of lipid oxidation products. This is contrary to the common behavior of anthocyanins in aqueous solutions, where their stability increases with decreasing pH. The best color stability of the black carrot extract in the oil-in-water emulsion was observed at pH 4 instead of pH 6, due to a pH-dependent deprotonation reaction. Gaining insights into the complex relationship between pH, lipid oxidation, and the color stability of anthocyanin-rich black carrot extracts in ω-3 fatty acid–rich emulsions challenges conventional understanding and offers valuable guidance for improving the use of anthocyanins as food colorants in emulsion-based applications.

Practical Applications

This study provides insight into the stability of anthocyanin-based natural colorants, such as black carrot extract, in oil-in-water emulsions, facilitating their application in lipid-containing food systems. It provides a more comprehensive understanding of the pH-dependent degradation mechanisms of anthocyanins, extending current knowledge from aqueous solutions to emulsion-based conditions.

Abstract Image

查看原文本刊更多论文

pH对黑胡萝卜提取物亚麻籽水包油乳剂脂质氧化及花青素稳定性的影响

较强的pH敏感性和自由基反应活性限制了花青素作为食品着色剂在乳化食品中的应用。本研究的目的是全面了解富含ω-3脂肪酸的水包油乳剂中富含花青素的黑胡萝卜提取物的颜色稳定性与pH值的关系。花青素的稳定性受脂质氧化程度的影响，而脂质氧化程度又与pH值有关。在不添加黑胡萝卜提取物的情况下，乳状液中脂质氧化产物的形成加快，这与花青素的抗氧化活性有关。此外，由于铁等催化金属的溶解度较高，脂质氧化随着pH的降低而增加。花青素表现出pH依赖性降解动力学：pH 2 (k = 1.44 h−1)> pH 3 (k = 0.3 h−1)> pH 4 （k = 0.06 h−1）× pH 6 (k = 0.09 h−1)，与脂质氧化产物浓度降低相关。这与花青素在水溶液中的常见行为相反，在水溶液中，花青素的稳定性随着pH值的降低而增加。由于pH值依赖于去质子化反应，在pH值为4而不是pH值为6时，观察到黑胡萝卜提取物在水包油乳液中的最佳颜色稳定性。深入了解富含ω-3脂肪酸乳剂中富含花青素的黑胡萝卜提取物的pH值、脂质氧化和颜色稳定性之间的复杂关系，挑战了传统的理解，并为改善花青素作为食品着色剂在乳剂中的应用提供了有价值的指导。本研究揭示了以花青素为基础的天然着色剂（如黑胡萝卜提取物）在水包油乳剂中的稳定性，促进了其在含脂食品体系中的应用。它提供了对花青素的ph依赖性降解机制的更全面的理解，将目前的知识从水溶液扩展到乳化条件。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Food Science 工程技术-食品科技

CiteScore

7.10

自引率

2.60%

发文量

412

审稿时长

3.1 months

期刊介绍： The goal of the Journal of Food Science is to offer scientists, researchers, and other food professionals the opportunity to share knowledge of scientific advancements in the myriad disciplines affecting their work, through a respected peer-reviewed publication. The Journal of Food Science serves as an international forum for vital research and developments in food science. The range of topics covered in the journal include: -Concise Reviews and Hypotheses in Food Science -New Horizons in Food Research -Integrated Food Science -Food Chemistry -Food Engineering, Materials Science, and Nanotechnology -Food Microbiology and Safety -Sensory and Consumer Sciences -Health, Nutrition, and Food -Toxicology and Chemical Food Safety The Journal of Food Science publishes peer-reviewed articles that cover all aspects of food science, including safety and nutrition. Reviews should be 15 to 50 typewritten pages (including tables, figures, and references), should provide in-depth coverage of a narrowly defined topic, and should embody careful evaluation (weaknesses, strengths, explanation of discrepancies in results among similar studies) of all pertinent studies, so that insightful interpretations and conclusions can be presented. Hypothesis papers are especially appropriate in pioneering areas of research or important areas that are afflicted by scientific controversy.