Blueberry jam: sensorial analyzes and effect of storage on physical and chemical properties.

Resumo

The proposal of the present research includes eight Blueberry jam formulations, from Rabbiteye species (Climax and Powder Blue varieties). For gelling, four formularizations were used: synthetic ATM pectin (F1), pectin obtained from passion fruit skin extraction (F2), synthetic BTM pectin (F3), and synthetic BTM pectin mixed with gums mixture (F4). Product Sensorial tests were performed and sensorial attributes evaluated were flavor, color, texture and appearance. According with sensorial tests and the Anova results, it could be concluded that the two more accepted formularizations were: F2 and F4 (For Climax variety) and F1 e F4 (for Powder Blue variety). Therefore, these formulations were evaluated for pH, total soluble solids, titratable acidity, water activity, total and reducing sugars, total and anthocyanins, from the first day of storage and after 30, 90 and 120 days to analyze the storage effect on jam characteristics. Jam processing reduces anthocyanins content (about 57% for conventional formulations and 35% for light jam); however, the jam may still be considered anthocyanins source, owing to the high content even after processing. After 40 storage days a significant decrease on jam anthocyanin levels was observed, except the products with higher sugar contents. Comparing the anthocyanin levels at time zero and after 120 days of storage, it appears that the decrease in pigment concentration was higher in the climax of fruit variety (approximately 44%). After 30 days of storage, the percentage of acidity, pH, water activity, moisture and soluble solids content remained constant.

DOI: 10.14685/rebrapa.v5i1.150