The Use of Probiotic-Loaded Single- and Double-Layered Microcapsules in Cake Production.

To date, the probiotic product development studies have mostly focused on dairy-based foods. However, endowing bakery products with probiotic properties not only provides a variety in food selection but would also potentially improve public health when the consumption rates are taken into consideration. This study aimed to incorporate single- and double-layered microcapsules containing Saccharomyces boulardii, Lactobacillus acidophilus, and Bifidobacterium bifidum, produced by spray drying and chilling, in cake production. Microcapsules were added after baking to the three different types of cakes (cream-filled, marmalade-filled, and chocolate-coated). Additionally, the microcapsules were injected into the center of the cake mix and baked at 200 °C for 20 min, for plain cake only. After baking of plain cakes, the count of S. boulardii and L. acidophilus as determined in the double-layered microcapsules produced by spray chilling was 2.9 log cfu/g. The survivability rates of S. boulardii and L. acidophilus were also determined as 67.4 and 70.7% in this microcapsule, respectively. However, there were no viable B. bifidum detected after baking. The free forms of these probiotics did not survive in any plain cake experiments. Single-layered microcapsules produced by spray chilling provided a better protective effect on the probiotics in cream-filled and marmalade-filled cake samples during storage, particularly the cream-filled cakes. This study showed that combined spray chilling and spray drying microencapsulation techniques (double-layered microcapsules) could increase the survivability of probiotic microorganisms during the cake baking process. During storage, the cake samples had a near neutral pH value, and the textural properties deteriorated due to staling. However, cake staling had a limited effect on the sensorial attributes of the cakes and the samples could be readily consumed after storage for 90 days.