Biological properties of black mulberry-derived food products (Morus nigra L.)

BACKGROUND: Black mulberry is a good source of bioactive compounds and especially of anthocyanin. OBJECTIVES: The objective of this study was to evaluate the morphological, biochemical, technological and antioxidant properties of black mulberry fruit and fruit-derived food products. MATERIALS AND METHODS: Total anthocyanin content, total sugar content, ascorbic acid content, pH and antioxidant activity was analyzed in black mulberry juice, jam, jelly, syrup, liqueur, compote, wine and cake. All products were produced from selected genotypes of black mulberry grown in Slovakia. RESULTS: Reducing sugar content ranged from 6.50 mg.kg(-1) FM in wine to 60.01 mg.kg(-1) FM in jam, ascorbic acid content was from 0.27 mg.100 g(-1) FM in wine to 1.10 mg.100 g(-1) FM in fruits conserved in honey without sterilization. Content of anthocyanin varied from 21.4 in wine to 106.4 mg.dm(-3) in fresh juice. Detected pH values ranged from 3.28 in jelly to 3.69 in liqueur. All tested samples had strong DPPH center dot radical scavenging activity with the best values in black mulberry compote with honey -74.02% and jam 71.22% FM. Differences between the genotypes were significant and the content of the anthocyanin was significantly higher in genotypes with lower fruit weight (P <= 0.05). CONCLUSION: The results showed that black mulberry fruits and derived products are rich in biologically active compounds and can be used in food industry and human nutrition.