JOURNAL OF FOOD COMPOSITION AND ANALYSIS www.elsevier.com/locate/jfca Journal of Food Composition and Analysis 16 (2003) 121–132 Original Article Chemical and fatty acid composition of ‘‘Lac ! on gallego’’ (dry-cured pork foreleg): differences between external and internal muscles Ad ! an Veiga, ! Angel Cobos*, Cristina Ros, Olga D ! ıaz ! Area de Tecnolog ! ıa de Alimentos, Departamento de Qu ! ımica Anal ! ıtica, Nutrici ! on y Bromatolog ! ıa, Facultad de Ciencias, Universidad de Santiago de Compostela, 27002 Lugo, Spain Received 21 December 2001; received in revised form 14 June 2002; accepted 4 September 2002 Abstract Chemical and fatty acid composition of external and internal muscles of ‘‘Lac ! on gallego’’ (dry-cured pork foreleg) have been studied. This product is manufactured in the northwest of Spain from the fore extremity of the pig, following a series of phases, salting, washing, standing and drying, that last approximately 35 days. Significant differences were found between external and internal muscles in dry matter, water activity, TBA, nitrates and nitrites. Lipolysis has been analysed by studying the changes of glycerides, phospholipids and free fatty acids in lipids from green forelegs and dry-cured forelegs. Glycerides accounted for about 72% of total lipids in both green and dry-cured forelegs. Phospholipid content decreased from 23% to 17% while free fatty acid fraction doubled its values (from 5% to 11%) in both external and internal muscles. The proportion of PUFA of phospholipids was significantly lower in dry-cured forelegs compared with the values of green forelegs. The amount of PUFA of free fatty acid fraction of dry-cured pork foreleg was significantly lower in external muscles than in internal muscles; these differences could be due to oxidation of these fatty acids. r 2003 Elsevier Science Ltd. All rights reserved. Keywords: Dry-cured foreleg; Chemical composition; Lipolysis; Fatty acids 1. Introduction Dry-cured pork foreleg ‘‘Lac ! on gallego’’ is a typical product manufactured in the northwest of Spain where it has a great economical importance. In 2001, Lac ! on gallego was recognized in the European Union with the Protected Geographical Indication (PGI) label (Commission of the *Corresponding author. Tel.: +34-982223325; fax: +34-982285872. E-mail address: cobusa@lugo.usc.es (A. Cobos). 0889-1575/03/$ - see front matter r 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0889-1575(02)00162-X