Shelf‐life determination of an egg‐based cake, relating sensory attributes microbiological characteristics and physico‐chemical properties

Abstract

The study of sensory, microbiological and physical-chemical properties are important in local products where the level of inspection and quality control are low. The present study aimed to determine the shelflife of an egg-based moist cake, relating sensory, microbiological and physical-chemical properties. Slices of Cavacas de Resende were collected, stored at two different temperatures (7 and 22 °C) and analysed over time (0, 6 h, 1, 2, 4, 7 and 10 days). Salmonella, Bacillus cereus, Listeria monocytogenes and Escherichia coli, were not detected. On 10 days of storage at 22 °C results were above the allowed limit for Staphylococcus aureus. The counts of mesophiles, moulds and yeasts exceeded the allowed limits in the last days of storage at 22 °C. Most of sensory variables presented a positive and highly significant correlation with freshness, with emphasis to brightness (crust and batter), moist, softness and succulence. Hardness and fracturability (both instrumental) showed a highly significant correlation with sensory freshness. Loss of moisture and mould development were main factors for product quality decrease. Better conservation of the product was achieved at 7 °C with a shelf-life limit of 7 days. At 22 °C, it is recommended to consume the product in 3 days.

Listeria monocytogenes from Food Products and Food Associated Environments: Antimicrobial Resistance, Genetic Clustering and Biofilm Insights

“…According to ISO 11290-1 [63], half Fraser broth (VWR Chemicals, Radnor, PA, USA) was used as the main enrichment medium, followed by incubation at 30 • C for 24 h. Then, 0.1 mL of the aliquots were transferred to Fraser broth (VWR Chemicals) and incubated at 37 • C for 48 h. Cultures obtained from half Fraser broth/Fraser broth were then subjected to further analysis: 0.1 mL aliquots were placed on supplemented Oxford agar (VWR Chemicals) and supplemented Palcam agar (VWR Chemicals), incubated at 37 • C for 24-48 h. To confirm the colonies, a series of tests including catalase reaction, Gram-stain, hemolysis assessment, and carbohydrate utilization were performed according to ISO 11290-1 [64]…”