Lipid characteristics of dry-cured “Tocino” during the manufacturing process. Effects of salting intensity and ripening temperature

Journal of Food Composition and Analysis, 52 (2016) 33–43

http://dx.doi.org/10.1016/j.jfca.2016.07.005

The fatty acid composition, the lipid characteristics and the colour parameters of Tocino, a salted and ripened meat product made from subcutaneous backfat from pig, were studied throughout manufacturing of the product. The effects of the ripening temperature and of the duration of the salting process were also studied. Ripening process caused a significant (P < 0.001) decrease in the total and some individual polyunsaturated fatty acids (C18:2n-6, C18:3n-3, C20:2n-6, C20:3n-6, C20:4n-6, and C20:3n-3), particularly in the polar lipid fraction (total polyunsaturated fatty acids descended from 13.6 to 3.5% of total methyl esters). Increased ripening temperature (from 8 to 12 °C) and longer duration of salting (from 2 to 4 days) caused a significantly greater decrease in the content of polyunsaturated fatty acids. The nutritional and health index values indicated that Tocino is not a healthy product. During the ripening stage, Tocino underwent moderate lipolysis and very intense lipid oxidation (final values of 3.57–5.09 mg KOH/g of fat and 0.84–1.16 mg malondialdehyde/kg). Increasing the ripening temperature significantly increased (P < 0.001) both lipolysis and fat oxidation, while increasing the duration of salting only had a significant positive effect on oxidation processes. Longer ripening times led to a significant increase (P < 0.001) in the b* values (from 8.81 to 18.7–23.7) and significant decreases in the a* (from 7.10 to −3.31 – −4.04) and L* (from 81.5 to 66.4–70.2) values.

Oxidation of edible animal fats. Comparison of the performance of different quantification methods and of a proposed new semi-objective colour scale-based method

Food Chemistry, 217 (2017) 743–749

http://dx.doi.org/10.1016/j.foodchem.2016.09.009

The agreement among the results determined for the main parameters used in the evaluation of the fat auto-oxidation was investigated in animal fats (butter fat, subcutaneous pig back-fat and subcutaneous ham fat). Also, graduated colour scales representing the colour change during storage/ripening were developed for the three types of fat, and the values read in these scales were correlated with the values observed for the different parameters indicating fat oxidation.

In general good correlation among the values of the different parameters was observed (e.g. TBA value correlated with the peroxide value: r = 0.466 for butter and r = 0.898 for back-fat). A reasonable correlation was observed between the values read in the developed colour scales and the values for the other parameters determined (e.g. values of r = 0.320 and r = 0.793 with peroxide value for butter and back-fat, respectively, and of r = 0.767 and r = 0.498 with TBA value for back-fat and ham fat, respectively).