Ill. Admin. Code tit. 77, § 785.230 – Bacterial Estimate Classification

a) Method of Testing: Methods for determining the bacterial estimate of milk shall be those described in the 15th edition of Standard Methods for the Examination of Dairy Products. Samples shall be analyzed at an official State laboratory or at a laboratory approved by the Department. (See 77 Ill. Adm. Code 463)
b) Frequency of Tests: At least once a month at irregular intervals, a mixed sample of each producer's milk shall be tested and results submitted to the Department.
c) Acceptance of Milk: If the sample of milk is classified as No. 1 or No. 2, the producer's milk shall be accepted without qualification. If the sample is classified as "Undergrade" (probational) the producer's milk shall be accepted for a temporary period of 4 weeks. The producer of "Undergrade" milk shall be notified by the Department.
d) Retests: Additional samples shall be tested and classified at least weekly. The producer and the Department will be notified of the results. This procedure of testing at least weekly and accepting "Undergrade" milk shall be continued for a time period not exceeding 4 weeks. If at the end of this time the producer's milk does not meet the acceptable bacterial estimate requirements (No. 1 or No. 2), it shall be excluded from market by notification from the Department in writing. If the first or second weekly tests are acceptable, routine monthly testing may begin.

Milk shall be classified for bacterial estimate as follows by one of the methods listed in Table 230:

TABLE 230

Bacterial Estimate Classification	Direct Microscopic Count Standard Plate Count, or Plate Loop Count.
No. 1	Not over 200,000 per ml
No. 2	Not over 1,000,000 per ml
Under Grade	Over 1,000,000 per ml