Development and evaluation of sundae-type Coalhada containing Lactobacillus paracasei and blueberry (Vaccinium ashei) preparation

“Coalhada” is a type of fermented milk (made with Lactococcus lactis spp. lactis and Lactococcus lactis spp. cremoris) very popular in Brazil, which is widely consumed due to its pleasant texture and mild taste and aroma. Its acceptance is possible to increase by adding a fruit preparation. Fermented milk is the most common food matrix used for delivery probiotic bacteria, which are able to survive to the passage through the gastrointestinal tract, reaching the colon in high concentration where they can effectively bind and subsequently, improve the body functions as a whole. In this study, two formulations of “Coalhada” were developed which resemble a sundae (in which, the fruit preparation stays on the botton of the package and the fermented milk on the upper part) used for a blueberry preparation. The formulation F1 was the control, with no addition of probiotic bacteria and to the formulation F2 the probiotic Lactobacillus paracasei was added. The formulations were evaluated over 14 days of storage under refrigeration. The characteristics evaluated in the product were: moisture, pH, acidity, lipids and ash content and all of them were not significantly affected (p > 0.05) by the addition of the probiotic bacteria. However, the addition of Lactobacillus paracasei significantly decreased (p < 0.05) the syneresis of the product during the refrigerated storage. Blueberry preparation had a high antioxidant activity which was 330.8 µmol TEAC 100 g-1 and the total phenolic compounds content was 36.65 mg GAE 100 g-1, showing that the addition of blueberry can also improve the nutritional characteristics of the final product. The count of the lactic acid bacteria (including the probiotic one) remained high (> 109 CFU g-1) during the 14 days of storage, but the shelf life of the two formulations was around seven days, since in the second week of storage the counts of yeasts and molds reached 102 CFU g-1 (which is the maximum allowed by Brazilian legislation). It is important to note that there was no addition of preservatives to the blueberry preparation, although the Brazilian legislation allows this and it could extend the shelf life of the final product, because yeasts and molds found in the product, probably comes from the fruits. Concluding that it was feasible to use blueberries in functional fermented milk such as “sundae-type Coalhada” and that it was a good way to innovate and to add value to the final product.