No abstract

In this study, we evaluated the effects of the storage time on the physicochemical properties, bioactive compound content, and antioxidant capacity of jam prepared from grape peel extract to explore its potential as a supplementary food and/or functional ingredient. The ethanolic extract from Syrah var. grape peel exhibited high bioactive compound concentrations and antioxidant activity. The jam stability (prepared with 8.9% of extract) at 14°C was evaluated at 0, 15, 30, 45, and 60 days. The jam was found to contain high concentrations of polyphenolic compounds (137.0 ± 3.2 mg of gallic acid equivalent/100 g), total flavonoids (128.5 ± 23.0 mg of equivalent/100 g), and total anthocyanins (92.5 ± 4.0 mg of cyanidin equivalent/100 g). However, a large reduction in the flavonoid (70%–90%), anthocyanin (29%–35%), and phenolic (23%–30%) content was observed during storage. The free radical‐scavenging activity (DPPH − ), ferric reducing antioxidant power (FRAP), and β‐carotene‐linoleic acid assays revealed the great antioxidant potential of the jam prepared from grape peel extract, which exhibited significant levels of radical‐neutralizing activity, especially as determined by the DPPH method with EC 50 values ranging from 2.3 ± 0.1 to 3.9 ± 0.1 µg/ml. High R 2 values ( p > 0.90) were obtained for the correlation between the DPPH results and the concentrations of the compounds of interest. In summary, the high bioactive compound contents and antioxidant capacity of the jam produced from grape peel suggest that it may provide health benefits as a source of natural antioxidants upon incorporation to several food industry products.

Propolis is a product of varied consistency and colour, produced by bees from materials collected from various parts of the plants. It has a complex chemical composition, which depends on the regional flora. Therefore, there are various types of propolis, making comparison between them a difficult task. In the present study, a survey of studies with propolis from the state of Bahia, Brazil, was carried out. We identified 17 scientific papers and eight patents dealing with propolis produced in Bahia. In these works three amongst the 13 types of propolis reported in Brazil were listed. Almost all studies report the antimicrobial activity potential of propolis types 6, highlighting its low percentage of flavonoids. It was also noted that the incentive given to the production of propolis type 13 in Bahia, also known as “própolis vermelha”, is due to the overall aggregate value of this product.