In any prosecution for the sale of food, drug or cosmetic in violation of any provision of this subtitle, proof of the analysis of the article so sold may be given in evidence on the part of the prosecutor, notwithstanding the fact that the article may have been purchased by some person other than a representative of the department, if such article shall immediately after such sale be delivered by the purchaser to the department.
The department shall, in the presence of the person from whom the request or demand was made, or of a witness who may be the purchaser, divide the article into two or more parts and preserve the sample in the same manner as prescribed by section 24:3-4 of this Title.
N.J.S. § 24:3-6