The market milk samples sold in Seoul area from about the middle of September to about the middle of November in 1982 were grouped glass bottle, polyethylene pack, pure pack and tetrabrik pack by the type of container, and were "tested on the bacterial consecutive changes to different containers and storage temperatures.
The results obtained were as follows:
1. When the market milk samples were stored below 5°C, standard plate counts and coliform counts did not exceed the legal limit for the four days, the term of validity. -
2. The polyethylene packs showed the highest standard plate counts of the four type of containers.
:3. At room temperature (18°´22°C), the standard plate counts of glass bottle sample showed over 40, 000 per ml. between the second and third day, those of polyethylene packs within´ 24 hours, and those-- of pure packs within 72 hours. This is in excess of the legal limit of standard plate counts for pasteurized milk. At 32°C, 7 samples of ten samples -of glass bottle, polyethylene packs and pure packs exceeded the legal limit within 16 hours, and the other three samples exceeded between 16 h ours and 24 hours.
4. Tetra-brik pack samples did not show no bacterial counts, so these samples proved to be the sterilized milk.
5. As the storage time increased, coliform bacteria appeared at room temperature and 32°C, and these
samples exceeded l0 per ml. within 24 hours at room temperature and within ´8 hours at 32°C.
This is in excess of the legal limit of ´coliform bacteria for pasteurized milk.
6. Polyethylene pack samples showed more coliform counts than those in other packs as well as in - the standard plate counts. I
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