UJI MIKROBIOLOGIS PADA SAMPEL MAKANAN DAN MINUMAN

The aims of this study were to find out and comprehend the determinant ways of contamination level on food and beverage biologically. This study was conducted in Laboratory of Applied Microbiology, Faculty of Mathematics and Natural Sciences, Universitas Negeri Medan, North Sumatera in September 2016. This study consisted of ALT test of bacteria, namely test of Eschericia coli,
Salmonella typhosa and Staphylococcus ureus as well as ALT test of fungi. The sample were dried noodle and melon-flavoured beverage. The results showed that: based on the quantitative test, it was obtained that dried noodle sample
contained bacteria colony of 85 for dilution 10-4, 42 for dilution 10-5, and 3 for dilution 10-6. Meanwhile the melon-flavoured beverage did not contain any bacteria colony, neither for dilution 10-2, dilution 10-3, nor dilution 10-4. The fungi test on dried noodle did not contain any fungus for dilution 10-4, 1 fungus for dilution 10-5, and 6 fungi for dilution 10-6, meanwhile for melon-flavoured beverage, there were containing 2 fungi for dilution 10-2, and they were not grown by itself, neither for dilution 10-3 nor for 10-4. Based on the qualitative
test, it was obtained that dried noodle for dilution 10-1 showed positive sign on
PW medium, that was color muddiness occurred. Hence, the post-hoc test was subsequently employed on VJA medium by scratching pure bacteria cultivate of Staphylococcus aureus onto petri dish and the result was positive, showed that
the black colony of yellow zone was formed. On SCB medium, in order to show whether Salmonella typhosa exists or not, it was added the result of dilution 10-1 of dried noodle sample which was positive due to the color muddiness upon
medium. Furthermore, the post-hoc on SSA medium was then employed by scratching pure bacteria cultivate of almonella typhosa onto petri dish and the result was also positive in which the green colony was formed. Meanwhile,melon-flavoured beverage contained negative bacteria colony, thus the post hoc was not employed yet.