La. Admin. Code tit. 7 § XXXI-105

Current through Register Vol. 50, No. 11, November 20, 2024

Section XXXI-105 - Testing Raw Milk Samples for Butterfat Content

A. No person shall test milk for butterfat content without benefit of license by the commissioner.

B. Babcock Method; Procedure. Deliver 17.5 ml. of milk into an 8 percent milk test bottle and temper to approximately 70° F. Add 17.5 ml. of sulphuric acid (sp. gr. 1.82 to 1.83 at 68° F) to contents of test bottle or such amount necessary to render a deep chocolate color. Mix the contents for three minutes in a mechanical shaker, then centrifuge for five minutes at proper speed. Add hot water 140-150° F to within 1/4 inch of the graduated neck on the test bottle and centrifuge for two minutes. Add 140-150° F water to approximately the 7 percent mark on the graduated test bottle and centrifuge for one minute. Remove the tests from the centrifuge and place into a 138-140° F tempering bath for five minutes, making certain that the water level is above all the fat columns. Measure the fat column from the extreme point of the lower meniscus to the uppermost point of the upper meniscus. Percentage of butterfat shall be determined to the nearest tenth percent and posted immediately. Glassware and equipment shall be drained and cleaned immediately upon termination of use.

C. Milko-Tester Mark III; Procedure. The diluent solution shall be prepared, mixed, stored and utilized according to manufacturer specifications. The accuracy of calibration and performance shall be ascertained. The device shall be flushed four times with diluent and 10 tests performed prior to calibration and official testing. During periods of official testing the device shall be flushed four times with diluent after two routes have been tested or at approximately 35 test intervals. Samples shall be tested at 98-100° F and applied to the automatic pipette in such manner as to avoid contact with the pipette. Test results from the Milko-Tester and other similar devices shall be determined to the nearest hundredths percent and posted immediately following each test. Upon termination of its use the device shall be flushed four times with diluent solution and a Grade A Homogenized sample (3 3/10 to 3 1/2 percent) placed therein to remain until the device is used again the following day(s).

D. Majonnier Method. The procedure employed in this test shall be in accordance to A.O.A.C. [Association of Official Analytical Chemists] approved standards without modification.

La. Admin. Code tit. 7, § XXXI-105

Promulgated by the Department of Agriculture, Dairy Stabilization Board, LR 1:164 (March 1975).

AUTHORITY NOTE: Promulgated in accordance with R.S. 40:889, R.S. 40:891 and R. S. 40:883.