Detection of non-milk fat in milk fat by gas chromatography and linear discriminant analysis.
Gas chromatography was utilized to determine triacylglycerol profiles in milk and non-milk fat. The values of triacylglycerol were subjected to linear discriminant analysis to detect and quantify non-milk fat in milk fat. Two groups of milk fat were analyzed: A) raw milk fat from the central region of Mexico (n = 216) and B) ultrapasteurized milk fat from 3 industries (n = 36), as well as pork lard (n = 2), bovine tallow (n = 2), fish oil (n = 2), peanut (n = 2), corn (n = 2), olive (n = 2), and soy (n = 2). The samples of raw milk fat were adulterated with non-milk fats in proportions of 0, 5, 10, 15, and 20% to form 5 groups. The first function obtained from the linear discriminant analysis allowed the correct classification of 94.4% of the samples with levels <10% of adulteration. The triacylglycerol values of the ultrapasteurized milk fats were evaluated with the discriminant function, demonstrating that one industry added non-milk fat to its product in 80% of the samples analyzed.
Gutiérrez
R
R
Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana Unidad Xochimilco, Calz. Hueso 1100, Villa Quietud, 04960 Coyoacán, México D.F. México. reygut@correo.xoc.uam.mx
Vega
S
S
Díaz
G
G
Sánchez
J
J
Coronado
M
M
Ramírez
A
A
Pérez
J
J
González
M
M
Schettino
B
B
D000818:Animals; D002849:Chromatography, Gas; D016002:Discriminant Analysis; D005223:Fats / Q000032:analysis* / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis; D008892:Milk / Q000737:chemistry* / Q000592:standards*; D010938:Plant Oils / Q000737:chemistry; D014280:Triglycerides / Q000737:chemistry
D005223:Fats; D010938:Plant Oils; D014280:Triglycerides