Tulum cheeses were manufactured from raw ewe's milk and ripened in goat's skin bags (tulums) or plastic containers to understand the effect of ripening container on the chemical composition, biochemistry, microbiology, and volatile composition of Tulum cheeses during 150 d of ripening. Chemical compositions of the cheeses ripened in tulums were significantly different and the moisture contents decreased rapidly in those cheeses because of the porous structure of the tulum. Higher microbial counts were detected in the cheeses ripened in plastic than in cheeses ripened in tulums. Differences in nitrogenous compounds and total free AA of the cheeses were not significant. Total concentrations of free AA in cheeses increased with age and Glu, Ala, Val, Leu, and Phe were the most abundant AA in the cheeses. Urea-PAGE of pH 4.6-insoluble fractions of the cheeses during ripening showed similar degradation patterns in all cheeses. Peptide profiles by reversed-phase HPLC of pH 4.6- and ethanol-soluble or ethanol-insoluble fractions of the cheeses revealed only minor differences in the concentrations of some peptides among the cheeses; however, age-related changes in peptide concentrations were significantly different among the cheeses. Cheeses were analyzed at 90 d of ripening for volatile compounds by solid-phase microextraction gas chromatography-mass spectrometry. One hundred volatile components were identified, including 11 acids, 16 esters, 12 methyl ketones, 7 aldehydes, 22 alcohols, 7 sulfur compounds, 6 terpenes, and 19 miscellaneous compounds. The main components were short-chain fatty acids, 2-butanone, diacetyl, and primary alcohols. Quantitative differences in several volatile compounds were evident among the cheeses. Cheeses ripened in tulums or plastic had similar aroma patterns, but the concentrations of some components were different.

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-The effect of pasteurization of cheese milk and cooking temperature of the curd on proteolysis of Malatya cheese was examined during ripening. The cheeses that were characterized by the scalding of curd in hot whey were manufactured from raw or pasteurized milk and the curds were scalded in hot whey at 60, 70, 80 or 90°C. Differences in the levels of pH 4.6-soluble nitrogen between cheeses were significant (P < 0.05) after 30 days of ripening. Urea-polyacrylamide gel electrophoresis of the pH 4.6-insoluble fractions showed that both α s1 -and β-caseins were not extensively degraded, especially after 30 days of ripening, but β-casein was less degraded than α s1 -casein. Analysis of peptide profiles of the pH 4.6-soluble fractions by RP-HPLC showed significant differences in the concentrations of some peptides between the cheeses. Principal component analysis distinguished the cheeses made from raw or pasteurized milk based on their peptide profiles. The results suggest that the pasteurization of cheese milk had a greater effect on peptide profiles of cheese than scalding temperature of the curd.Malatya cheese / proteolysis / scalding / raw milk / pasteurizationRésumé -Effet de la pasteurisation du lait et de la température de chauffage du caillé sur la protéolyse du Malatya, un fromage de type Halloumi. Les effets de la pasteurisation du lait de fabrication et de la température de cuisson du caillé sur la protéolyse du fromage Malatya ont été examinés pendant l'affinage. Les fromages qui sont caractérisés par la cuisson du caillé dans du *Corresponding author (通讯作者): ahayaloglu@inonu.edu.tr Dairy Sci. Technol. 90 (2010) Article published by EDP Sciences lactosérum chaud ont été fabriqués à partir de lait cru ou pasteurisé et les caillés ont été traités dans du lactosérum chauffé à 60, 70, 80 ou 90°C. Les différences de teneur en azote soluble à pH 4,6 entre fromages étaient significatives (P < 0,05) après 30 jours d'affinage. L'électrophorèse sur gel de polyacrylamide en milieu urée des fractions insolubles à pH 4,6 a montré que les deux caséines β et α s1 n'étaient pas beaucoup dégradées, en particulier après 30 jours d'affinage, mais la caséine β était moins dégradée que la caséine α s1 . L'analyse du profil peptidique par chromatographie RP-HPLC des fractions solubles à pH 4,6 a montré des différences significatives dans les concentrations de quelques peptides entre fromages. L'analyse en composante principale différenciait les fromages au lait cru de ceux au lait pasteurisé à partir de leur profil peptidique. Les résultats suggèrent que la pasteurisation du lait de fabrication a un effet plus grand sur les profils peptidiques des fromages que la température de chauffage du caillé.fromage Malatya / protéolyse / chauffage / lait cru / pasteurisation