First experiments at the Life Dairy in Katete

Beginning of May I did my first laboratory experiments at the yoghurt factory in Katete. The aim was to check if it is possible to make petri dishes with MRS agar medium and then to observe if some Lactobacillus bacteria can grow on it. For do this simple experiment I needed a lot of laboratory equipment, which I bought in Kampala and brought to Katete by matatu and boda-boda. So, if one time you need some laboratory equipment in Uganda ask me, I know where you can find it 🙂

The first step of this experiment consisted in weighing the MRS agar in a glass bottle, add water and a small amount of growth factor “Tween 80” (picture 1). The solution was boiled to dissolve the medium completely, using a stove and a cooking pan (2 and 3). For sterilization I used a high pressure cooker for 20 min, which was also heated on a stove (4 and 5). The children made big eyes, when they saw the steam coming out of the cooker (6). When the agar was cooled down at around 50 °C I poured the petri dishes with the agar (7). To ensure a “sterile” environment I used a spirit burner. After the solidification of the medium in the dishes I spread pasteurized milk (on this dishes no micor-organisms should grow) and yoghurt (the bacteria from the starter culture should grow) (8). After an incubation time of 3 days at room temperature, I observed the growth on the petri dishes (9, 10 and 11). I was happy, that everything worked and that the results correspond with the expected results.