# Sheep's and Goat's Frozen Yoghurts Produced with Ultrafiltrated Whey Concentrates
## 3 Results and Discussion
Except for formulation 6 (goat's frozen yoghurt with 5.0% inulin incorporation), all products presented adequate levels (>log 6 UFC g\({}^{-1}\)) of LAB. However, lower counts of streptococci in all goat's frozen yoghurts were observed. Table 7 presents the LAB counts of both frozen yoghurt types over the 21-day storage period. In the case of ewe's yoghurts without added inulin, it can be observed that adequate levels of LAB were maintained for 2 weeks. However, at the 21 st day of storage, lactobacilli were present at low levels (ca. 5 log CFU g\({}^{-1}\)), while streptococci were absent. Regarding goat's frozen yoghurts without inulin addition, adequate levels of LAB were observed for seven days, but streptococci were already present at low levels by the 7 th day of storage. At the 14 th and 21 st days of storage, lactobacilli were absent while streptococci surpassed 6 log UFC g\({}^{-1}\). The formulation of goat's frozen yoghurt containing 2.5% inulin presented low levels of streptococci (5.42 log UFC g\({}^{-1}\)) at the first day. Lactobacillus were absent at the 7 th, 14 th and 21 st days of storage. Streptococci also presented low counts over frozen storage. Curiously, the formulation containing 5.0% inulin presented inadequate levels of LAB at the first day, while at the 7 th day LAB counts surpassed 6 log CFU g\({}^{-1}\). At the 14 th and 21 st day of storage, the pattern was similar to that observed with formulation 5 (2.5% inulin). Generally, it can be indicated that ewe's concentrated whey was more effective in promoting LAB growth. Strong interactions (\(p<0.001\)) among species, inulin amount and storage time were observed for lactobacilli counts, while they were less significative, except for species-storage time interaction, for streptococci counts (Table 8). Further studies must be undertaken to confirm these results. In fact, several research works regarding frozen yoghurts indicate high survival rates for both LAB and probiotic bacteria, especially when microencapsulation was used. In another work [42], a commercial yoghurt culture was used as a starter culture while free and immobilized probiotic cells were added as adjuncts for frozen yoghurt production. The viability of the immobilized probiotic cells was maintained at high levels for 90 storage days at \(-18\)\({}^{\circ}\)C, while the viability of free probiotic cells decreased ca. 10%. _L. bulgarcus_ counts reduced by approximately 3 log cycles and no counts of _S. thermophilus_ were detected by the end of freezing storage. Alves and coworkers [24] produced goat's milk frozen yoghurt with 1% inulin, 0.25% starter culture (_Streptococcus thermophilus_ and _Lactobacillus bulgarcus_) and 0.25% probiotic culture (_Bifidobacterium animals_ and _Lactobacillus acidophilus_) to verify its probiotic potential after 7 and 120 days of storage. During storage, probiotic bacteria were reduced, but the product showed probiotic potential due to both _B. animalis_ and _L. acidophilus_, which reached the minimum desirable numbers until the end of storage. The product received good scores for global appearance, color, aroma and taste, while texture and aftertaste had lower acceptance rates. Other researchers investigated four experimental groups of caprine frozen yoghurt produced with the addition of fresh and spray-dried jambolan fruit pulp and _Bifidobacterium animalis_ subsp. _lactis_. The addition of _B. animalis_ decreased the pH of frozen yoghurt samples. Lower overrun values (14.2-22.6%) were observed for all samples when compared to our data. The frozen yoghurt samples with probiotic presented high cell counts (9 log CFU g\({}^{-1}\)) and a high probiotic survival rate throughout the 90 days of frozen storage [25]. Goat milk and goat milk plus inulin were used as encapsulating agents of Bifidobacterium-terium BB-12 and applied in frozen yoghurt to evaluate the antagonistic effect against _Escherichia coli_. The production of organic acids by bifidobacteria was directly related to the decrease in the _E. coli_ counts. In plate counts, _E.