Short communication, Note

https://doi.org/10.5562/cca1756

Sample Preparation Methods for the Determination of the Antioxidative Capacity of Apple Juices

Iva Juranović Cindrić ; Laboratory of Analytical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
Martina Kunštić ; Laboratory of Analytical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
Michaela Zeiner ; Division of Analytical Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
Gerhard Stingeder ; Division of Analytical Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
Gordana Rusak ; Department of Biology, Faculty of Science, University of Zagreb, Marulićev trg 9a, HR-10000 Zagreb, Croatia

Abstract

The elevated ecological awareness nowadays led to a higher consumption of apples juices.
Apples juices are rich in dietary fiber, pectin, potassium, and vitamins A and C as well as in different
classes of phenolic compounds, which can protect the human body against oxidative stress by scavenging
oxygen free radicals. During production and storage some bioactive compounds might decompose resulting
in a reduced antioxidative capacity.
Common methods for the determination of the antioxidative capacity of other food stuff are based
on the extraction of the compounds under study using acetone, which is senseless in aqueous juices. But
acetone might have an influence on the compounds responsible for the antioxidative capacity. Thus, self
made apple juice samples were analyzed without organic solvent as well as mixed with acetone to see differences
caused by the solvent. The results obtained with both procedures were compared using a paired
t-test in order to see statistically significant differences in the results. No statistically significant differences
were found between the testing with and without acetone. Thus the time of analysis, the amount of solvents
needed, and the required labor force can be reduced without loosing analytical quality. Total content
of phenolic compounds ranged from 400 to 650 mg gallic acid equivalent /L (Folin-Ciocalteu method) and
antioxidative capacity from 1.0 to 1.6 mmol Trolox®/L (ABTS assay). (doi: 10.5562/cca1756)

Keywords

apple juice; antioxidative capacity; Folin-Ciocalteu method; ABTS assay

Hrčak ID:

74810

URI

https://hrcak.srce.hr/74810

Publication date:

13.11.2011.

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