Physico and chemical characterisation of blackberry jam

Blackberries have a short shelf-life and thus are used mainly as raw material for the food industry. In spite of the wide use of blackberries as processed products, not much is known about the effects of processing and storage concerning the chemical composition of such products. In this paper, jams were prepared from seven blackberry cultivars grown in Brazil. Jams were evaluated after processing and storage for 40 and 90 days at room temperature for some parameters related to quality such as the pH, total soluble solids, total titratable acidity, humidity, soluble carbohydrates and total anthocyanin content. The heat applied to blackberry jam products reduced the anthocyanin content at an average of 8.8%. Storage time also reduced the anthocyanin content at an average of 32% after 40 days at room temperature decreasing to 11% in the next 50 days of storage. The anthocyanin content obtained in blackberry jams ranged from 98.58 mg/100 g (´97 selection) to 170.66 mg/100 g (Guarani), which characterizes this food as a rich source for phenolic compounds.

Rubus sp.; cultivars; jam; storage; composition; anthocyanins

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