Effect of modified atmosphere packaging on physicochemical and microbiological characteristics of Graviera Agraphon cheese during refrigerated storage

Abstract

The aim of this work was to examine the effect of modified atmosphere packaging on the physicochemical and microbiological changes of Graviera Agraphon cheese during refrigerated storage. Blocks of Graviera Agraphon cheese weighing around 200 g were packaged under natural (control) or modified atmosphere packaging (MAP) conditions (50% N2 – 50% CO2) and stored at 4 °C or 10 °C for up to 85 d. Prior to packaging, groups of cheese blocks were inoculated with one each of the following foodborne pathogens at around 104 log cfu/g: Listeria monocytogenes, Salmonella Typhimurium, Escherichia coli O157:H7 or Staphylococcus aureus, whilst further groups of cheese blocks were not inoculated. The protein, fat, moisture and salt contents as well as the pH of control and MAP cheese samples did not change significantly (P > 0.05) throughout 4 °C storage, while the pH values of control and MAP cheese samples were significantly (P < 0.05) reduced at 10 °C storage. At 10 °C storage, yeasts and molds, psychrotrophs and lactic acid bacteria (LAB) were significantly higher (P < 0.05) for the normal atmosphere than the MAP cheese samples after the 4th, 8th and 4th days, respectively. At 4 °C storage, the yeasts and molds or psychrotrophs were significantly higher (P < 0.05) than those of control after the 6th and 15th days, respectively at 4 °C storage. All foodborne pathogens showed a higher decrease (P < 0.05) at 10 °C than 4 °C storage. S. aureus proved more sensitive in inactivation in the MAP conditions than atmospheric conditions. L. monocytogenes and S. aureus presented a higher decrease than that of E. coli O157:H7 and S. Typhimurium. In conclusion, MAP proved efficient in retarding the growth of yeasts, molds, psychrotrophs and E. coli O157:H7, L. monocytogenes, S. Typhimurium and S. aureus in Graviera Agraphon cheese during refrigerated storage at 4 and 10 °C.

Optimization of Modified Atmosphere Packaging for Sheep’s Milk Semi-Hard Cheese Wedges during Refrigerated Storage: Physicochemical and Sensory Properties

“…Headspace gas composition, physicochemical, colour, and instrumental textural and sensory analyses were conducted on the cheese samples at 14,21,28,35,42,49, and 56 storage days; the same analyses were carried out on the cheeses prior to packaging.…”

A Sustainable Material for Sheep’s Cheese Wedges Stored under Different Atmosphere Conditions

“…In a previous study with Idiazabal PDO cheese using PA/PE (20/70) as the packaging material [23], none of the physicochemical parameters measured in wedges showed significant differences (p ≤ 0.05), neither for packaging treatment or conservation time, nor for the interactions between them. Kirkin et al [51] and Solomakos et al [42] did not observe significant changes in the composition of cheese samples throughout the study. The main protein content and total solids remained almost constant for six storage months in vacuum-packaged San Simon da Costa cheeses.…”

“…This decrease might be attributed to gas dissolution in the cheese matrix, its consumption by anaerobic microorganisms, or by CO 2 loss through the barrier film [22,41]. In a similar study by Solomakos et al [42] with sheep cheese packaged under 50/50% CO 2 /N 2 conditions, after 10 storage days at 4 • C, the CO 2 concentration decreased by 17.15% and remained stable thereafter.…”

Advances in Active Packaging: Perspectives in Packaging of Meat and Dairy Products

“…to that of the controlled cheese that suffered no changes under the same conditions (P>0.05). Yet those same MAP and controlled cheese values were fairly decreased to 5.10±0.3 and 4.95±0.3 during the end of the 16th and 24th day of storage at a temperature of 10°C [111].…”