RESUMO
A number of ready-to-use shelf-stable intermediate-moisture (IM) spiced mutton and spiced chicken products were developed with a combination of hurdles (reduced moisture, vacuum packing, and irradiation). The water activity of the products was reduced to about 0.80 either by grilling or by hot-air drying. These IM products were vacuum packed and subjected to gamma radiation processing at 0 to 10 kGy. Microbiological analyses revealed a radiation dose-dependent reduction in total viable counts and in numbers of Staphylococcus species. IM meat products that did not undergo radiation treatment showed visible mold growth within 2 months. The products subjected to irradiation at 10 kGy showed an absence of viable microorganisms and also retained high sensory acceptability for up to 9 months at ambient temperatures.
Assuntos
Irradiação de Alimentos/métodos , Embalagem de Alimentos/métodos , Produtos da Carne/microbiologia , Staphylococcus/efeitos da radiação , Animais , Bovinos , Galinhas , Comportamento do Consumidor , Qualidade de Produtos para o Consumidor , Relação Dose-Resposta à Radiação , Raios gama , Humanos , Produtos da Carne/efeitos da radiação , Ovinos , Suínos , Paladar , Vácuo , ÁguaRESUMO
Changes in aroma and coloring properties of saffron (Crocus sativus) after gamma-irradiation at doses of 2.5 and 5 kGy (necessary for microbial decontamination) were investigated. The volatile essential oil constituents responsible for aroma of the spice were isolated by steam distillation and then subsequently analyzed by gas chromatography/mass spectrometry (GC/MS). No significant qualitative changes were observed in these constituents upon irradiation, although a trained sensory panel could detect slight quality deterioration at a dose of 5 kGy. Carotene glucosides that impart color to the spice were isolated by solvent extraction and then subjected to thin-layer chromatography and high-performance liquid chromatography (HPLC). Fractionation of the above pigments into aglycon and glucosides was achieved by using ethyl acetate and n-butanol, respectively. Analysis of these fractions by HPLC revealed a decrease in glucosides and an increase in aglycon content in irradiated samples. The possibility of degradation of pigments during gamma irradiation is discussed.
