Characterization of the chemistry, biochemistry and volatile profile of Kuflu cheese, a mould-ripened variety

• Published in: Food science & technology Vol. 41; no. 7; pp. 1323 - 1334
• Main Authors: Hayaloglu, A.A., Brechany, E.Y., Deegan, K.C., McSweeney, P.L.H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2008; Elsevier
• Subjects: acidity; Biological and medical sciences; Blue cheeses; cheese ripening; cheeses; food analysis; food chemistry; Food industries; Fundamental and applied biological sciences. Psychology; Kuflu cheese; Milk and cheese industries. Ice creams; mold-ripened cheese; molds (fungi); Mould; Principal component analysis; protein content; Proteolysis; traditional foods; Volatile compounds; water content; Turkey (country); Mould; Blue cheeses; Volatile compounds; Proteolysis; Kuflu cheese; Principal component analysis; Volatile compound; Alteration; Dairy product; Profile; Characterization; Blue cheese; Variety
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2007.08.020

The chemistry, biochemistry and volatile compounds of Kuflu cheese, a Turkish mould-ripened variety were studied. A total of 29 samples were analysed and the titratable acidity, moisture, salt-in-moisture, fat-in-dry matter and total protein contents (as mean values) were 0.96%, 49.97%, 7.49%, 12.18% and 37.84%, respectively, and the pH of the cheeses was 6.29. Indices of proteolysis (i.e., the levels of pH 4.6- and trichloroacetic acid-soluble nitrogen) were high; however, these values were lower than those of other Blue cheeses probably due to proportionally higher levels of total nitrogen and salt-in-moisture in Kuflu cheese samples. Urea-polyacrylamide gel electrophoresis of the pH 4.6-insoluble fractions of the cheeses showed that both α s1- and β-caseins were extensively degraded, but β-casein was less degraded than α s1-casein. RP-HPLC peptide profiles of the pH 4.6-soluble fractions from Kuflu cheeses showed that some minor quantitative differences were found between the samples, while peptide profiles of the samples were qualitatively similar. One hundred and thirty-eight compounds were identified in the volatile fractions of Kuflu cheese by gas chromatography–mass spectrometry (GC–MS) using a solid -phase microextraction technique. Ketones and alcohols were the principal class of volatile components in Kuflu cheeses, and terpenes and sulphur compounds were found at substantial levels in the majority of the samples, but aldehydes and lactones were present at low levels. The RP-HPLC and GC–MS data were analysed by principal component analysis based on their peptide and volatile profiles, respectively. Kuflu cheeses obtained from different markets had some differences in terms of chemical composition, proteolysis and patterns of aroma compounds.