Commercial probiotic Lactobacillus sp. cultures (Lb. paracasei, Lb. casei and Lb. acidophilus) in fermented drinks made from goat's milk

Abstract

Over the last few years, an increase has been confirmed in the consumption of food products containing strains showing probiotic features. Lactobacillus sp. strains, a major part of the lactic acid bacteria, are considered to be main probiotic micro-organisms, especially Lb. acidophilus, Lb. paracasei, Lb. rhamno-sus, Lb. casei, and Lb. johnsonie. Additionally, some strains of Lb. plantarum are classified into this group as are Bifidobacterium bifidum and Bifidobacterium longum. The objective of the research was to produce a new generation of fermented drinks from goat's milk by means of commercial probiotic Lactobacillus sp. cultures containing single species (Lb. Paracasei, Lb. casei, and Lb. acidophilus,) and to assess their quality features during a three week storage period (5 ± 1 °C). Three variants of experimental products were produced: NP-A (containing Lb. Paracasei AD400), NP-B (containing Lb. casei 01), and NP-C (with a Lyofast La 3 culture containing Lb. acidophilus). The experimental drinks were sensory assessed and underwent microbiological, physical-chemical, and rheological analyses after the 1st, 7th, 14th, and 21st day of cooling storage. It was found that the experimental drinks produced from the goat's milk were characterized by very good and good sensory features and a required number of live cells of probiotic bacteria (at least 106 cfu/g) during the storage. Their titratable acidity, pH, content of acetaldehyde, viscosity, and hardness depended significantly on the type of drink analyzed and the time of cooling storage.