As the cheese market faces strong international competition, the optimization of production processes becomes more important for the economic success of dairy companies. In dairy productions, whey from former cheese batches is frequently re-used to increase the yield, to improve the texture and to increase the nutrient value of the final product. Recycling of whey cream and particulated whey proteins is also routinely performed. Most bacteriophages, however, survive pasteurization and may re-enter the cheese manufacturing process. There is a risk that phages multiply to high numbers during the production. Contamination of whey samples with bacteriophages may cause problems in cheese factories because whey separation often leads to aerosol-borne phages and thus contamination of the factory environment. Furthermore, whey cream or whey proteins used for recycling into cheese matrices may contain thermo-resistant phages. Drained cheese whey can be contaminated with phages as high as 109 phages mL-1. When whey batches are concentrated, phage titers can increase significantly by a factor of 10 hindering a complete elimination of phages. To eliminate the risk of fermentation failure during recycling of whey, whey treatments assuring an efficient reduction of phages are indispensable. This review focuses on inactivation of phages in whey by thermal treatment, ultraviolet (UV) light irradiation, and membrane filtration. Inactivation by heat is the most common procedure. However, application of heat for inactivation of thermo-resistant phages in whey is restricted due to negative effects on the functional properties of native whey proteins. Therefore an alternative strategy applying combined treatments should be favored – rather than heating the dairy product at extreme temperature/time combinations. By using membrane filtration or UV treatment in combination with thermal treatment, phage numbers in whey can be reduced sufficiently to prevent subsequent phage accumulations.

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The anterior insula and the frontal operculum are regarded as the primary taste cortex. Modulation of the frontal operculum by the yogurt containing the olive oil extract suggests that it might be possible to simulate fat-triggered sensations in the brain on the gustatory level, possibly by ingredients the body implicitly associates with fat. This trial was registered at clinicaltrials.gov as NCT01716286.

Although ice cream is a good vehicle to convey probiotics to human hosts, probiotics are not stable in ice cream because of milieu conditions, species-and product-related properties. Studies on the incorporation of probiotics into ice cream have been conducted; however, there is a need for development of a production method in which probiotics maintain their viability and the physicochemical properties of ice cream are preserved. In this study, the aim was to compare the physicochemical properties of ice cream containing Lactobacillus acidophilus (ATCC 4356) that was incorporated using different methods, as well as to determine the viability of L. acidophilus in the samples. Ice cream was produced using three methods: method 1, ice cream mix was fermented with L. acidophilus prior to freezing; method 2, milk (10% of total milk used in the preparation of ice cream mix) was taken and subsequently fermented with L. acidophilus; the fermented milk was introduced to the remaining ice cream mix prior to freezing; and method 3, L. acidophilus was added to the ice cream mix and the mix was not fermented with L. acidophilus prior to freezing. The viability of L. acidophilus in ice cream was better for methods 1 and 2 of ice cream production when compared to method 3. The viable counts after 90 days of storage were higher than the target level (>10 6 cfu.g −1) only in samples produced using methods 1 and 2.

Tickborne encephalitis, a zoonotic virus infection, is transmitted to humans usually by the bite of an infected tick. It may also be acquired by ingesting infected dairy products. In this study, the infectivity of tickborne encephalitis virus, suspended in milk and other media, remained unchanged during a period of five days of storage at 8°C. After heat treatments in the range of 60 to 80°C, a decrease of approximately 4 or 4.5 log units in the virus titre was observed. Kinetic parameters for the inactivation were calculated, and the line of equal effects showing a 3-log inactivation was determined.