Aflatoxin M1 in pasteurized and ultrapasteurized milk with different fat content in Mexico.
High per capita milk consumption in Mexico indicated a strong need for documentation of aflatoxin M1 (AFM1) levels in milk. A survey of 580, 2-liter samples (n = 290), was conducted to quantify AFM1 using high-performance liquid chromatography, considering two maximum tolerance levels (0.05 and 0.5 microg/liter). We relate aflatoxin levels in the seven most consumed brands from different regions, with two processes (pasteurized and ultrapasteurized), different expiration dates, and different fat content: whole fat (28, 30, and 33 g), half-skimmed (10, 16, and 20 g), light (1, 2, and 4 g), and with vegetable oil. Pasteurization and ultrapasteurization did not diminish AFM1 contamination present at levels of 0 to 8.35 microg/liter in 40% of the milk samples at concentrations > or = 0.05 microg/liter and in 10% of the samples at > or = 0.5 microg/liter. Statistically significant relationships were AFM1 contamination with brand (P = 0.002 at the > or = 0.05 microg/liter level and P = 0.034 at the > or = 0.5 microg/ liter level) and higher AFM1 levels with mild or warm seasons of the year (P = 0.0003). Samples with greater fat content had slightly more probability (P = 0.067) of being contaminated by AFM1 at the > or = 0.5 microg/liter level. The milk with the lowest contamination of AFM1 was a brand imported as powder and rehydrated in Mexico.
Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de Mexico, México, DF. magdac@servidor.unam.mx
Magda
M
Carvajal
Adolfo
A
Bolaños
Francisco
F
Rojo
Ignacio
I
Méndez
D016607:Aflatoxin M1 / Q000032:analysis* / Q000096:biosynthesis; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003257:Consumer Product Safety; D005223:Fats / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis; D005511:Food Handling / Q000379:methods*; D005519:Food Preservation / Q000379:methods; D006358:Hot Temperature; D006801:Humans; D008800:Mexico; D008892:Milk / Q000737:chemistry* / Q000382:microbiology; D012621:Seasons
D005223:Fats; D016607:Aflatoxin M1