RESUMO
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate's corn tortilla. Lees, which is mostly made of pulque's microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.
Assuntos
6-Fitase/metabolismo , Agave/microbiologia , Bebidas Alcoólicas , Farinha/análise , Fosfatos/análise , Ácido Fítico/metabolismo , Bebidas Alcoólicas/análise , Bebidas Alcoólicas/microbiologia , Ácido Ascórbico/análise , Disponibilidade Biológica , Cálcio/análise , Cálcio/farmacocinética , Fermentação , Ferro/análise , Ferro/farmacocinética , Magnésio/análise , Magnésio/farmacocinética , México , Valor Nutritivo , Selênio/análise , Selênio/farmacocinética , Zea mays , Zinco/análise , Zinco/farmacocinéticaRESUMO
On December 1997, 94 corpses of green turtles, Chelonia mydas, were found at the Ojo de Liebre lagoon (OLL) adjacent to the industrial operation of Exportadora de Sal S. A (ESSA), the largest saltworks in the world, owned by the Mexican Government and Mitsubishi Corporation, located in Baja California Sur, Mexico. Every year about 551 x 10(6) m3 of seawater is solar evaporated, producing 7 x 10(6) tons of salt and 24.6 x 10(6) m3 of bitterns, the latter being discharged into the OLL, which is a costal lagoon of the Pacific Ocean. ESSA claimed that bitterns contain the same salts present in seawater, but 20-fold more concentrated than the former. Ion chromatography with a conductivity detector and ion suppression was used to determine the F-, Cl-, SO4(2-) and CO3(2-) contents of seawater, brines and bitterns collected at ESSA. Furthermore, the osmolality of brines and bitterns from ESSA was measured. F- content in bitterns was 60.5-fold more than that in seawater. The bitterns osmolality was 11,000 mosm/kg of water, whereas the turtle's plasma osmolality was about 400 mosm/kg of water. We concluded that the dumping of bitterns into the ocean should be avoided.