Abstract Freeze concentration process was used to concentrate milk until the third stage of freeze concentration. Thus, two samples of ice creams were manufacture, one with milk and the other with concentrated milk from the first stage of block freeze concentration, and denominated ice cream 1 and ice cream 2, respectively. Both ice creams were characterized according to physicochemical characteristics, overrun, microscopy, melting rate, texture, color, and rheological properties. The use of concentrated milk influenced the physicochemical properties of ice cream 2, promoting an increase in the total solids, protein, carbohydrates, and ashes content. Moreover, it was noted that ice cream 2 had a higher overrun, lower firmness, smaller ice crystals, and tended to color greenish and yellowish, however had a higher melting rate and larger hysteresis area. The models of the Power Law and Casson satisfactorily described the rheological behavior of ice creams, which proved to be a Newtonian fluid.

Abstract The skimmed milk was previously concentrated by the block freeze concentration and, thus, used in the manufacture of an ice cream sample with Bifidobacterium BB-12 addition. This sample was compared with two control samples, one ice cream manufactured with skimmed milk, and the other an MRS broth, which supplies an excellent base for comparison of the bacterial survival. All three samples were submitted to the in vitro gastrointestinal assays from the mouth to the large intestine. The initial Bifidobacterium BB-12 viable cell count (> 8 log CFU/g or mL) of both ice cream samples ensured their classification as probiotic products. This behavior was noted during all in vitro steps (from the mouth until the colon). From the mouth to the ileum was observed that both ice creams showed a slight oscillatory probiotic count. For the ice cream manufactured with concentrated milk, it was observed a high bifidobacteria protective effect in the descending colon, with probiotic viable cells count and recovery rate values equal to 9.88 log CFU/g and 112.02%, respectively. Finally, it was possible to conclude that as well as the ice cream with milk, the concentrated milk served as a succesful probiotic carrier.