The changes of flavour and aroma active compounds content during production of Edam cheese

Evaluation of selected parameters of edam type cheese packed under foil with natural antimicrobial agents

The aim of this study was to evaluate the properties of essential oils packed in foils derived from different plant sources used in Edam type cheese on selected parameters (total viable count of microorganism, coliform bacteria, micromycetes, sensory parameters and instrumental colour). Essential oils have antibacterial and antifungal activities against microorganisms. However, the concentration of these substances applied in cheeses should be considered carefully because of their possible negative influences on sensory parameters. Mixture of the essential oils (clove/cinnamon/thymol in a 1:2:1 ratio), three concentrations (3.9 %, 6.6 %, 9.0 %), respectively mixture of the essential oils (eugenol/thymol/cinnamon in a 1:1:1 ratio), three concentrations (0.10 %, 0.19 %, 0.24 % as a 5% solution in limonene in a dry coating) were used. Samples wrapped in polystyrene dishes were stored in the refrigerator at 3 - 6 °C. Analyses were made after 48 h, 168 h (144 h), 216 h (240 h) respectively. Taste is the most affected by presence of essential oils. The effectiveness of the film with the mixture A seems to be more effective in eliminating microorganisms. Negative sensory changes were observed at higher concentration. Based on the results, the tested foils seem to be promising materials suitable for packaging of cheese.

Fat reduction and whey protein concentrate addition alter the concentration of volatile compounds during Prato cheese ripening

The impact of fat reduction and the addition of whey protein concentrate (WPC) on the volatile compounds profile of Prato cheese was evaluated for 210 days of storage at 12 °C. Full fatPrato cheese, Prato cheese with fat reduction and reduced fatPrato cheese with 0.5% (w/v) WPC were made, and replicated on a different day. Cheese volatile compounds were extracted by solid phase microextraction (SPME) and separated, identified and quantified by gas chromatography coupled to a mass spectrometry detector (GC-MS). Fat reduction and the WPC addition resulted in lower concentrations of compounds derived from lipolysis and free fatty acid catabolism. Fat reduction generated higher levels of diacetyl and acetoin, both from the citrate metabolism, at days 5 and 30. A similar pattern was observed for sulfur compounds derived from the catabolism of free amino acids, at day 120. Higher levels of diacetyl (day15), dimethyl disulfide (days 150-180) and dimethyl trisulphide (days 150-210) were found for cheese with WPC. These differences might have occurred due to alterations in the structure and polarity of the protein matrix caused by fat reduction and the WPC addition.