Microbiological and physicochemical changes during ripening of Camembert cheeses made from raw and pasteurized cow milk produced in Tizi-Ouzou (north of Algeria)

Abstract

This study was carried out on two types of Camembert produced in the region of Tizi-Ouzou (northern Algeria), one artisanal (AC) made from raw milk and the other industrial (IC) made from pasteurized milk. This work shows the effect of milk quality and cheese making processes on the progress of physicochemical and microbiological parameters throughout a maturation period of 12 days. The result shows that the repining microflora and undesirable microbial populations were significantly higher (P < 0.05) in the artisanal Camembert (AC) than in the industrial Camembert (IC). The physicochemical and microbiological parameters, during the ripening of the cheeses developed in a similar way with significant differences according to the type and the stage of maturation. During the cheese repining period, AC showed more extensive (P < 0.05) lipolysis and proteolysis than IC. SDS-PAGE of water-soluble proteins (WSP) and insoluble fractions showed more extensive degradation of s-casein (s-CN) than β-casein (β-CN). The WSP profile, analyzed by Reversed-Phase High Performance Liquid Chromatography (RP-HPLC), was highest in AC than IC. The highest WSP profile was recorded at the 12th day of repining. The pathogenic flora decreased during the maturation process in AC. This development was confirmed by the results of the antibacterial effect of WSP, performed by the disc diffusion technique on Escherichia coli and Staphylococcus aureus strains. From this study, it can be concluded that AC has a better organoleptic quality, safe for the Algerian consumer and more profitable for the Algerian cheesemakers

Physicochemical Characteristics, Fatty Acids Profile and Lipid Oxidation during Ripening of Graviera Cheese Produced with Raw and Pasteurized Milk

“…In this study, the WSN/TN ratio slightly increased during ripening with no significant differences ( p < 0.05) among ripening stages. The comparison of the WSN/TN values between two types of cheese showed a higher WSN/TN value for raw milk cheese compared with the pasteurized one ( p < 0.05), consistent with previous studies [ 46 ], and shows that maturation occurs to agreater extentin raw cheese. The values of the WSN/TN ratio during ripening for both types of cheese are shown clearly in Figure 1 .…”