| Abstract: | The development of the microbial flora specifically involved in the spoilage of sliced beef livers packaged and stored under aerobic conditions at 0 and 3 °C for 14 days was studied. Changes in the pH value of the product were also determined. The possibility that pH value could be considered as a quick and reliable indicator of incipient spoilage was particularly considered. All microbial groups (except micrococci) showed differences in their rates of growth between 0 and 3 °C. Pseudomonads and lactic acid bacteria were the main components of the spoilage flora. When the 37 °C aerobic plate counts (APCs) reached 105–106 CFU g?1 and the 20 °C APCs and pseudomonad counts reached 106–107 CFU g?1, visible surface colonies (VSCs) were observed. The presence of VSCs is the most important criterion to determine organoleptic beef liver spoilage and has hence enabled us to establish a shelf-life of up to 8–10 and 5.5–6.5 days for samples stored at 0 and 3 °C respectively. Our study shows that the determination of pH, which is simple, economical and rapid, is capable of giving a reliable estimate of the spoilage status of beef livers. pH values lower than 6.15 may be considered as indicative of beef liver spoilage. © 1999 Society of Chemical Industry |
