FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY

Authors

STANISŁAW KALISZ, MICHAŁ WOLNIAK

Title

Changes of phenolics compounds during the storage of raspberry juices

Abstract

The objective of this study was to present changes in the level of anthocyanins, polyphenols and antioxidant activity in raspberry juices without and with pectin during their storage at 4°C. The anthocyanin content in fresh juices without and with pectin was 97,34 mg/100 ml and 93,5 mg/100 ml respectively. The pelargonidyno-3-soforozyd was the main monomer (72% of all anthocyanin composition). After 3 months storage at 4°C anthocyanin content in juices without and with pectin decrease to 23% and 16%, respectively. It was shown that content of polyphenols and antioxidant activity was reduced during storage. However unprofitable changes were smaller in juices with pectin. During storage the decrease in polyphenol content was observed, what resulted in lowering the antioxidant capacity. In case of juice without pectin the decrese reached 18% of initial value, while with the addition of pectin it was only 6%.

Keywords

raspberries, juice, anthocyanins, polyphenols, antioxidant activity, EPR, free radicals

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