No percentage of fat ascertained from a sample containing milk or cream that has been so treated as to cause it to test lower or higher than the test of the milk or cream from which it was taken shall be used as a basis of payment for milk or cream purchased or sold.
32 Del. Laws, c. 36, § 6; 40 Del. Laws, c. 92, § 7; Code 1935, § 639; 3 Del. C. 1953, § 3116.