Novel method of zinc ions supplementing with fermented and unfermented ice cream with using PEF

Bacteria of Lactobacillus rhamnosus B 442 were enriched with zinc ions using a pulsed electric field technology. The strain was added to the mix and used for the production of two types of ice cream: unfermented and fermented. Zinc content in the ice cream varied from 0.962 mg center dot 100 g(-1) to 1.81 mg center dot 100 g(-1). Differences were observed in some properties of unfermented and fermented ice cream. Lower fat content (from 4.86% to 4.92%) and lower hardness (3.88 N-4.32 N) were determined for the fermented ice cream, whereas the unfermented samples had higher meltability (1880s-1936s) and adhesiveness (from 29.66 Ns to -28.27 Ns). There was no statistically significant effect of the type of ice cream and Zn2+ addition on protein, ash and carbohydrate content in the final product. The viability of the bacteria was at a high level (4.09 center dot 10(8)-3.26 center dot 10(12)).