Composition and quantification of major polyphenolic compounds, antioxidant activity and colour properties of quince and mixed quince jams

Aims: The aim of the study was to establish whether the addition of some berries and fruits during quince jam processing, improves its colour and enriches it in polyphenol compounds, other than those found in quince fruits. Methods: Phenolic compounds were identified and quantified by LC-MS Q/TOF and HPLC. Antioxidant activity was measured by ABTS, DPPH and FRAP methods. The colour of jams was expressed as L, a*, b* value. Results: The total content of polyphenolic compounds in quince jam was 484.5 mg/100 g. The highest level of phenolic compounds and antioxidant activity (p<0.05) was observed in samples with the addition of chokeberry > black currant > flowering quince. The colour of examined jams could be due to the type of fruit addition, the nature of the pigments in these fruits. Conclusion: Overall, the results indicated that some mixed jams can represent a good source of antioxidant compounds and can have an attractive colour for the consumer.