Colour modification in a cured meat model dried by Quick-Dry-Slice process® and high pressure processed as a function of NaCl, KCl, K-lactate and water contents G. Ferrini, J. Comaposada, J. Arnau, P. Gou ⁎ IRTA, Finca Camps i Armet s/n, E-17121 Monells (Girona), Spain abstract article info Article history: Received 15 April 2011 Accepted 22 September 2011 Editor Proof Receive Date 24 October 2011 Keywords: Colour modification Salt substitutes Cured meat Quick-Dry-Slice process High pressure Colour changes of dry cured-restructured minced pork with different salt contents (15, 20, 30 or 40 g NaCl/kg of meat) and dried with QDS process® from 20 to 50% of weight loss were studied considering the effects of HPP (500 and 600 MPa, 7 min holding time), K-lactate addition (25.6 g/kg) and the 50% molar substitution of NaCl by KCl. Meat colour parameters, L* (lightness), a* (redness) and b* (yellowness), were measured. In all cases, L* decreased and a* increased as the water content decreased. The NaCl reduction or the addition of K-lactate did not show any significant effect on the colour. The substitution of NaCl by KCl only slightly increased b* in the driest samples. HPP treatment increased L* and reduced a* and b* in samples with highest water content, but it had no effect on the driest samples. Industrial relevance: The drying period for meat products is the slowest phase of the manufacturing process. For sliced products, the QDS process allows an import reduction in time. The results of this paper show that the moisture content at which the HPP is applied to the dry-cured products may protect them from colour changes. The NaCl reduction or the substitution of salt by KCl or K-lactate combined with QDS and HPP allows the pro- duction of drycured meat with reduced Na content, without important effects on appearance and with lower microbiological risks. © 2011 Elsevier Ltd. All rights reserved. 1. Introduction The colour of meat products is of major importance when con- sumers assess the product quality (Shahidi, Pegg, & George, 1995). Most of the changes in colour of dry cured meat are commonly caused by light, oxygen, temperature, processing and packaging conditions (Cava, Ladero, González, Carrasco, & Ramírez, 2009; García-Esteban, Ansorena, & Astiasarán, 2004; Mancini & Hunt, 2005; Rubio, Martínez, García-Cachán, Rovira, & Jaime, 2008). Some studies have also showed that drying time affects the colour (Acton & Dick, 1977; Chasco, Lizaso, & Beriain, 1996), which suggests that it is affected by, among others, the water content of the product. Other studies also proposed it (Pérez-Alvarez et al., 1999; Sanabria, Martin-Alvarez, & Carrascosa, 2004), but the evidence of dependence between colour and water content of product was not studied in depth. Sodium chloride and sodium nitrite are essential ingredients in cured meat products, contributing to their microbiological stability and to their characteristic colour (Doyle & Glass, 2010). Nowadays, there is a tendency to produce meat products with lower NaCl con- tent due to the proven relationship between dietary sodium intake and the risk of morbidity and mortality from cardiovascular diseases (Kannel, Garrison, & Wilson, 1986; Law, 1997). To overcome the lower microbiological stability of such products different approaches have been proposed: the substitution of NaCl by other ingredients, the use of new processing technologies (with lower microbiological risks), and/or preservative treatments. The latter can be chemical pre- servatives or physical treatments. Whatever was the approach select- ed, the quality of the final product perceived by consumers (being colour of major importance, as stated above) has to be maintained. Several studies have demonstrated that potassium chloride (KCl) could be used as partial substitute of sodium chloride (NaCl) in meat products (Gou, Guerrero, Gelabert, & Arnau, 1996). Substitu- tions of 50% of NaCl by KCl in fermented sausages of small calibre did not modify the colour though produced an increase in bitterness and hardness, detected by trained assessors (Gou et al., 1996; Guàrdia, Guerrero, Gelabert, Gou, & Arnau, 2008). However, these changes did not affect the consumer's acceptability (Guàrdia et al., 2008). These re- sults pointed out that it is possible to substitute 50% of NaCl by KCl in some products (with final water content between 20 and 25%) without reducing the consumer's acceptability. Potassium lactate (K-lactate) is an allowed preservative consid- ered to reduce the development of bacteria and, consequently, in- creases the shelf-life of meat products (Bidlas & Lambert, 2008; Ruusunen & Puolanne, 2005). Around 2% of K-lactate has been added to different dry-cured meat products without significant nega- tive effects on flavour or colour (Gou et al., 1996). Innovative Food Science and Emerging Technologies 13 (2012) 69–74 ⁎ Corresponding author. Tel.: +34 972 630 052; fax: +34 972 630 373. E-mail addresses: Gabriele.Ferrini@irta.cat (G. Ferrini), Josep.Comaposada@irta.cat (J. Comaposada), Jacint.Arnaui@irta.cat (J. Arnau), Pere.Gou@irta.cat (P. Gou). 1466-8564/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.ifset.2011.09.005 Contents lists available at SciVerse ScienceDirect Innovative Food Science and Emerging Technologies journal homepage: www.elsevier.com/locate/ifset