One of the oldest examples of the application of biotechnology. Nevertheless a very useful way of illustrating how micro-organisms can be used in manufacturing products and the importance of monitoring the steps along the way.This Microbiology of Yoghurt Kit investigates:The differential growth rates of Lactobacillus bulgaricus and Streptococcus thermophilusEstimation of the total bacterial populationTitration of acid producedMeasuring pHDetermination of clotting point of caseinThe kit provides sufficient practical activity to occupy a normal class of students at 16+ level working in groups. The concepts included in the kit are particularly suitable for A-Level students and for use at college level. These organisms present no particular safety problems.The kit contains:Yoghurt starter cultureIndicator papersResazurin tabletMicroscope slidesMethyl violetInoculating loopGram's iodineDroppersCarbol fuchsinPipettesPhenolphthaleinFull instructions