Joerg Hinrichs

Adaptation of bovine milk towards mares’ milk composition by means of membrane technology for koumiss manufacture

Abstract This study was carried out to determine the physical, chemical, microbiological and organoleptic properties of koumiss made from bovine milk. The bovine milk was modified according to the composition of mares’ milk using ultrafiltration, microfiltration and nanofiltration. Koumiss made from modified bovine milk and mares’ milk were compared. In order to assess options for a consistent fermentation, a starter culture, instead of the prevailing spontaneous flora in traditional manufacture of koumiss, was used. Key compositional factors modified were the contents of dry matter, mineral, protein and lactose and the casein-to-whey protein ratio. Koumiss made from modified bovine milk and by starter cultures was found to be very similar to koumiss from mares’ milk in terms of pH, titratable acidity, alcohol, proteolytic activity, apparent viscosity, and microbiological composition, when assessed both in the freshly made product and that after 15 days storage at 4°C.

Review: elimination of bacteriophages in whey and whey products

Asthecheesemarketfacesstronginternationalcompetition,theoptimizationofproductionprocesses becomes more important for the economic success of dairy companies. Indairy productions, whey from former cheese batches is frequently re-used to increasethe 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 cheesemanufacturing process. There is a risk that phages multiply to high numbers during theproduction. Contamination of whey samples with bacteriophages may cause problems incheese factories because whey separation often leads to aerosol-borne phages and thuscontamination of the factory environment. Furthermore, whey cream or whey proteinsused for recycling into cheese matrices may contain thermo-resistant phages. Drainedcheese whey can be contaminated with phages as high as 10