Effect of fatty acid composition and positional distribution within the triglyceride on selected physical properties of dry-cured ham subcutaneous fat J. Segura a , R. Escudero b , M.D. Romero de Ávila b , M.I. Cambero b, ⁎, C.J. López-Bote a a Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain b Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain abstract article info Article history: Received 28 May 2014 Received in revised form 8 January 2015 Accepted 20 January 2015 Available online 24 January 2015 Keywords: Triglycerides Fatty acid Positional distribution Slip point Texture profile analysis Subcutaneous fat Analysis of fatty acid (FA) positional distribution within the triglyceride (TG) and selected physical properties of dry-cured ham subcutaneous fat (SF) were carried out. The slip point (SP) of the SF was related to the concentra- tion and positional distribution of FA. When C16:0 was in Sn-2, the SP depended on the FA present in Sn-1,3. Hardness was related to the FA concentration in external positions of TG. A significant direct linear correlation between hardness against C18:0, SFA and average chain length (ACL) and inverse against C18:1, C18:2 and PUFA and unsaturation index (UI) in external positions was found. Adhesiveness was related to SFA, C16:0, C18:0, C18:1, MUFA, UI and ACL exclusively in Sn-2 position. A different role of FA in Sn-2 and Sn-1,3 positions on SP and texture properties of fat was found. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Variation in technological properties of meat largely depends on the productive conditions of pig (including genetics and feeding) and processes of muscle conversion into meat (Candek-Potokar & Skrlep, 2011) and it is an important drawback in the commercial setting. Lipids markedly affect the quality of dry-cured hams and other meat products not only because of their importance in oxidation and flavor development (Soto et al., 2010) but also because the physical character- istics of fat affect technological properties (Houben & Krol, 1983; Hugo & Roodt, 2007) and final acceptability (Fernández, Mourot, Lebret, Gilbert, & Monin, 2000). Lean swine genotypes are prone to produce soft, oily and floppy fat (Wood, 1984) with dramatic undesirable consequences in salting, flavor development and consistency of dry- cured meat products (Gandemer, 2002; Isabel et al., 2003; Maw, Fowler, Hamilton, & Petchey, 2003). High linoleic acid (C18:2 n -6) and low saturated fatty acid (SFA) concentration have been associated to low consistency, oiliness and soft texture (Bosi & Russo, 2004). Therefore, a number of feeding practices are implemented in different consortium rules aimed to the production of quality meat products, which emphasizes the importance of maintenance of C18:2n -6 and SFA within certain limits in pig tissues (Candek-Potokar & Skrlep, 2011). On the other hand, physical properties of adipose tissue are also affected by positional distribution of fatty acids (FA) within the triacyl- glycerol (TG) structure, those FA in the external position of the molecule (Sn-1 and Sn-3) having a higher effect on consistency and melting point (Smith, Yang, Larsen, & Tume, 1998). Moreover, evidence exists that dietary treatment may alter the proportion of FA in external (Sn-1 and Sn-3) and internal (Sn-2) position of the TG (King, Behrends, Jenschke, Rhoades, & Smith, 2004). The aim of this study was to establish a relationship between the main FA and TG structure with physical and textural properties of subcutaneous fat in dry-cured hams. 2. Materials and methods 2.1. Experiment design The experiment was conducted using 10 castrated barrows and 10 gilts (Landrace × Large White (25% Pietrain)), randomly selected at 80 kg body weight. Pigs were fed a commercial diet containing 2.41 Mcal/kg net energy and 162 g/kg crude protein. The source of dietary fat was lard (added 3.2%), rapeseed meal (8%) and soybean meal (10.7%). The calculated dietary fatty acid composition as 100 g fed was 0.97% (palmitic acid), 0.43% (stearic acid), 1.64% (oleic acid) and 0.95% (linoleic acid). Pigs had free access to diets. At 110 (±2.98) kg of body weight, the pigs were slaughtered. The right thigh from each pig was obtained at cutting (24 h after slaughter) and processed in a traditional Meat Science 103 (2015) 90–95 ⁎ Corresponding author. Tel.: +34 913943745; fax: +34 913943743. E-mail address: icambero@vet.ucm.es (M.I. Cambero). http://dx.doi.org/10.1016/j.meatsci.2015.01.008 0309-1740/© 2015 Elsevier Ltd. All rights reserved. Contents lists available at ScienceDirect Meat Science journal homepage: www.elsevier.com/locate/meatsci