Addition of vinegar to "cabeça de xara" made from Alentejano pig meat increases shelf life

Abstract

“Cabeça de xara” is a very typical product from Alentejo region. It’s a very particular type of galantine, made from meat, tongue and connective tissue removed from Alentejano pig breed heads. Usually this product has a parallelepiped shape, as those used in the present study, with 40 cm length and 14 cm height. The aim of this study was to evaluate the use of vinegar to increase the products’ shelf life without negatively affecting the physicochemical and microbiological parameters, as well as its sensorial attributes. Two different treatments were compared, namely control and vinegar, for three months using end product “cabeças de xara”. Three batches with two replicates per treatment were used. One-Way ANOVA was used for statistical analyses. The mean pH of the “cabeças de xara” with vinegar (5.48) was lower than the pH of the control treatment (6.05). However, no significant differences were observed between control and vinegar treatments regarding water activity (aw). The microbiological flora of the “cabeças de xara” showed no significant differences regarding yeasts and moulds. The counts of total mesophiles, psychrophiles, psychrophilic anaerobes and enterobacteria were higher in the control treatment. Only a few samples showed a minor contamination with Listeria monocytogenes. As expected, the counts for all microbial groups increased with time. Regarding sensorial analysis, panellists generally gave higher scores to the control “cabeças de xara”, however no differences were observed between control and vinegar “cabeças de xara” concerning the attributes marbled and colour and aroma intensity. Considering the results of the end product at three months shelf life, the vinegar “cabeças de xara” showed lower microbial counts, probably due to the lower pH values. Our data suggest that the sensorial panel prefers the control “cabeças de xara”; however, the panellists did not taste some of the control products due to contamination with Listeria monocytogenes. To our knowledge, this is the first report on the physicochemical, microbiological and sensorial characteristics of such a traditional product. Acknowledgements This work was supported by national funds through project PRODER (QREN/PRODER/Medida 4.1) and funded by FEDER Funds through the COMPETE and National Funds through FCT under the Strategic Project PEst-C/AGR/UI0115/2011. The authors thank PALADARES ALENTEJANOS, Lda. for their collaboration and A. Oliveira and G. Pias for their technical assistance.