(a) Methods of Testing. Milk shall be tested for bacterial estimate by using one of the following methods or by any other method approved by Standard Methods for the Examination of Dairy Products.

(1) Direct Microscopic clump count;

(2) Standard plate count;

(3) Plate loop count;

(4) Pectin gel plate count;

(5) Petrifilm aerobic count;

(6) Spiral plate count;

(7) Hydrophobic grid membrane filter count;

(8) Impedance/conductance count;

(9) Reflectance calorimetry.

(b) Frequency of Testing. A laboratory examination to determine the bacterial estimate shall be made on a representative sample of each producer's milk at least once each month at irregular intervals. Samples shall be analyzed at a laboratory in accordance with State regulations.

(c) Acceptance of milk. The following procedures shall be applied with respect to bacterial estimates:

(1) Whenever the bacterial estimate indicates the presence of more than 500,000 bacteria per ml., the producer shall be notified with a warning of the excessive bacterial estimate.

(2) Whenever two of the last four consecutive bacterial estimates exceed 500,000 per ml., the appropriate regulatory authority shall be notified and a written warning notice given to the producer. The notice shall be in effect so long as two out of the last four consecutive samples exceed 500,000 per ml.

(3) An additional sample shall be taken after a lapse of 3 days but within 21 days of the notice required in paragraph (c) (2) of this section. If this sample also exceeds 500,000 per ml., subsequent milkings shall be excluded from the market until satisfactory compliance is obtained. Shipment may be resumed when an additional sample of herd milk is tested and found satisfactory.

[67 FR 48975, July 29, 2002]