HOMOGENEITY OF FRUITS AND VEGETABLES COMMINUTED IN A VERTICAL CUTTER MIXER

The homogeneity of comminuted composites of 20 lb samples of apples, c abbage, and green beans containing field-incurred residues of p,p'-met hoxychlor was studied to determine whether a 5 min comminution in a 40 qt vertical cutter mixer produces a homogeneous composite and whether the size of test portions used accurately represents the composite. D uplicate test portions of 100, 50, 25, 10, 5, and 2 g taken from each of 6 separate sections of the mixer were analyzed by standard pesticid e residue methodology for p,p'-methoxychlor. Results of this study con firmed that comminution of fresh produce in a 40 qt vertical cutter mi xer, according to instructions described in the U.S. Food and Drug Adm inistration's Pesticide. Analytical Manual, Volume I, section 203B, pr oducer, a homogeneous composite, No significant differences were found in the data for the 3 crops taken from the 6 sections of the mixer, T est portion weights of 100, 50, and 25 g produced equivalent results f or all 3 crops, Statistically significant differences were observed fo r cabbage at 2, 5, and 10 g and for green beans at 2 g.