Studies into the Stability of 3-O-Glycosylated and 3,5-O-Diglycosylated Anthocyanins in Differently Purified Liquid and Dried Maqui (Aristotelia chilensis (Mol.) Stuntz) Preparations during Storage and Thermal Treatment.
Anthocyanin stabilities in diluted and differently purified maqui preparations were assessed during storage and thermal treatment at different pH values. By sequentially depleting the matrix, the influence of polar low-molecular-weight matrix constituents and non-anthocyanin phenolics was shown to be negligible. In contrast, pH substantially affected thermal stabilities of differently glycosylated cyanidin and delphinidin derivatives. At pH 3.6, half-lives of 3-O-glycosides were substantially shorter than those of respective 3,5-O-diglycosides. However, at pH 2.2, an inverse stability behavior was observed. Findings were corroborated using isolated pigments. Upon heating, cyanidin derivatives were more stable than their respective delphinidins, but their stability was similar during storage. Anthocyanins in liquid samples were more stable when stored at 4 °C as compared to 20 °C, whereas those in dried powders revealed maximum stability throughout storage. The study contains a detailed discussion and mechanistic hypothesis for the above-mentioned findings, providing insights relevant for food applications of maqui anthocyanins.
Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology and Analysis, University of Hohenheim , Garbenstrasse 25, D-70599 Stuttgart, Germany.
Johanna E
JE
Brauch
Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology and Analysis, University of Hohenheim , Garbenstrasse 25, D-70599 Stuttgart, Germany.
Mareike
M
Kroner
Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology and Analysis, University of Hohenheim , Garbenstrasse 25, D-70599 Stuttgart, Germany.
Ralf M
RM
Schweiggert
Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology and Analysis, University of Hohenheim , Garbenstrasse 25, D-70599 Stuttgart, Germany.|Biological Science Department, King Abdulaziz University , P.O. Box 80257, Jeddah 21589, Saudi Arabia.
Reinhold
R
Carle
D000872:Anthocyanins / Q000737:chemistry* / Q000302:isolation & purification; D045467:Elaeocarpaceae / Q000737:chemistry*; D005505:Food Coloring Agents / Q000737:chemistry* / Q000302:isolation & purification; D005638:Fruit / Q000737:chemistry; D006031:Glycosylation; D006207:Half-Life; D006358:Hot Temperature; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification
D000872:Anthocyanins; D005505:Food Coloring Agents; D010936:Plant Extracts
HPLC analysis; antioxidant activity; color stability; degradation kinetics; electrophilic attack; hydration equilibrium constants; illumination; pH; phenolic contents; temperature