artículo científico
Microflora of maize prepared as tortillas
Fecha
1975-06Registro en:
0099-2240
essn:1098-5336
Autor
Capparelli, Edward
Mata Jiménez, Leonardo
Institución
Resumen
Very little is known of the microflora in tortillas, the major component in the
diet of many Guatemalans and other Central Americans. Based in a Guatemalan
highland Indian village, this study examined the types and amounts of bacteria,
yeasts, and molds in tortillas and in their maize precursors. Coliforms, Bacillus
cereus, two species of Staphylococcus, and many types of yeast were the main
contaminants, but lowconcentrations of alpha-hemolytic Streptococcus, facultative
Clostridium, and other bacterial types were also found. When tortillas were
fll8t cooked, the bacterial counts dropped to 1,000or fewerorganisms per g, a safe
level for consumption. Under village conditions, hacterial counts regained
precooking levels (about 108 organisms/g) within 24 h and rose even higher after
48 h. Reheating caused very little change; hence, bacterial levels remained very
high in old tortillas kept for later consumption. A search for the sources of
contamination showed that most came from water used in preparation and from
the soiled hands of women preparing the tortillas. As an attempt to correct
certain nutritional needs of the population, the Institute of Nutrition for Central
America and Panama initiated a tortilla fortification project in the Guatemalan
village. The bacterial counts in fortified tortillas did not differ significantly from
those in ordinary tortillas. Furthermore, the level of contamination was constant
among tortillas of different sizes and among tortillas made from different types of
maize.