Microbiological, biochemical and compositional changes during ripening of Sao Jorge - a raw milk cheese from the Azores (Portugal)

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Kongo, JM (Author) Other; Gomes, AM (Author) Other; F. Xavier Malcata (Author) Other; McSweeney, PLH (Author) Other

Journal

Title: Food Chemistry

Vol. 112 No. 4

Pages: 131-138

ISSN: 0308-8146

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 7 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-003-Q48

DOI: 10.1016/j.foodchem.2008.05.067

Abstract (EN): The microbial, compositional and biochemical profiles of Sao Jorge cheese (PDO) obtained from three distinct cheese plants, throughout the ripening period were determined. Fully ripened cheeses (i.e. by 130 days) contained a total of 3.1 x 10(7) CFU g(-1) mesophilic bacteria, and a decrease in moisture content, concomitantly with an increase in salt content, was observed throughout the same time frame. The pH decreased until 30 days of ripening; thereafter, a slight increase was reported, up to 5.6 by the end of ripening. Urea-PAGE results showed extensive primary proteolysis, of both beta-casein and alpha(s1)-casein - degraded at essentially similar rates: plasmin and chymosin accordingly appear to be active in the cheese curd. RP-HPLC profiles of water-soluble fractions showed minor differences between 1 and 130 day old cheeses, whereas equivalent profiles of 7% (v/v) ethanol-soluble fractions contained several peaks, indicative of a heterogeneous mixture of products of proteolysis, that evolved with time.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8