Samples of deteriorated almond pastes were analyzed for their physicochemical and microbiological characteristics. The physicochemical determinations included the aw, pH, humidity, lipid content, acid degree value of the extracted lipids, and alcohol content. The microbiological determinations grouped the standard plate counts (SPC), total and fecal coliforms, enterococci, staphylococci, Salmonella , and yeasts. Some samples were then stored at room temperature (around 22°C) for periods up to 3 months and the alcohol Content of the deteriorated samples was determined. Results showed that the deterioration was due to yeasts. Some yeast isolates were characterized and used in the assays of inhibition by sorbic acid and cinnamon. The minimal inhibitory concentration (MIC) of sorbic acid was reduced in the presence of cinnamon.
Keywords: Almond paste; cinnamon; preservation; sorbic acid; yeast.