USE OF CHEESE WHEY FOR BIOMASS PRODUCTION AND SPRAY-DRYING FOR PROBIOTIC LACTOBACILLI

Often waste water containing cheese whey is a problem in disposal, if pollution is to be limited. Whey is used in various products such as yogurt to good effect, such products often being highly nutritious. However, much more can be done to on the one hand exploiting the possibilities offered by whey and on the other hand at the same time limiting the outflow in waste water.  Such possibilities were investigated by Dr Luisina Lavaria and co-workers in their study published in the Journal of Dairy Research, Volume 81 of 2014, pages 267 to 274, the title being:  Use of cheese whey for biomass production and spray drying of probiotic lactobacilli.

The use of cheese whey as a culture medium and a temperature protector for spray drying of lactobacilli was investigated in this study, as a means of adding value to the wastewater. An in-house formulated broth and dairy media (cheese and ricotta whey, and whey permeate) were assessed for their capacity to produce biomass of Lactobacillus (Lb) paracasei JP1, Lb. rhamnosus 64 and Lb. gasseri 37. Simultaneously, spray drying of a cheese whey-starch solution without lactobacilli cells was optimised using surface response methodology. Cell suspensions of the lactobacilli, produced in the broth, were spray-dried in the cheese whey-starch solution and their viability monitored throughout the period of storage of the powders, which lasted for two months.

Lactobacillus rhamnosus 64 was able to grow satisfactorily in at least two of the in-house formulated culture media and in the dairy media assessed. It also performed well in spray drying. The performance of the other strains was less satisfactory. The growth capacity, resistance to spray drying in cheese whey-starch solution and the negligible lost of viability during the storage period found by the authors, makes Lb. rhamnosus 64 a promising candidate for further technological studies for developing a probiotic dehydrated culture for foods. This should be achieved by utilising wastewaters of the dairy industry as growth substrate and thermo-protector, and spray drying which is a low-cost and widely-available technology.