Influence of pasteurization on the chemical, physical, and microbiological characteristics of uvaia pulp (Eugenia pyriformis Cambess)

The uvaia is a fruit native to Brazil that has been recognized for its high content of bioactive compounds. However, this fruit is highly perishable and, therefore, transforming it into pasteurized pulp is an alternative to increase its consumption and commercialization. Thus, the aim of this study was to evaluate the effect of pasteurization on the chemical, physical, and microbiological characteristics of the uvaia pulp. This study investigated the contents of sugar, phenolic compounds, flavonoids, antioxidant activity (FRAP and ABTS), ascorbic acid, carotenoid, color, E.coli , Salmonella sp., and mold and yeast of the pasteurized pulp samples (85 °C for 1 and 5 minutes), in comparison with the control (without pasteurization). The heat treatment reduced the content of fructose, glucose and sucrose of the pulp samples. The contents of phenolic compounds and flavonoids increased in the samples pasteurized for 1 minute, but decreased after 5 minutes of the treatment. There was a decrease in ascorbic acid and an increase in the antioxidant activity of the pulp samples when pasteurization time was increased. On the other hand, the total carotenoid content was not affected by the heat treatment. Pasteurization did not affect the color parameters L* and b*, but it increased the tendency to the red color (a*) of the pulps. In the microbiological results, no differences were noted between the control and the pasteurized samples. Thus, it is possible to conclude that pasteurization at 85 °C for 1 minute provided a better preservation of the characteristics of the uvaia pulp.