Effect of Olive Cake in Bísaro Pig Feed on Physicochemical Composition and Fatty Acid Profile of Three Different Muscles of Dry-Cured Shoulder

The purpose of this study was to assess the following effects: (1) the inclusion of olive in the animal's diet on the dry-cured shoulder; (2) the effect of curing on three different muscles (infraspinatus, supraspinatus, and subscapular); (3) the effect of different curing times (fresh shoulder, 6 months curing, and 12 months curing). For this purpose, forty shoulders were used, followed by a cold nitrite-free curing process with controlled humidity and temperature, according to the flowchart of a company that implements highly stringent standards in terms of food safety and quality. Samples were evaluated for their physicochemical composition and lipid profile. All the physicochemical composition parameters were significantly different (p < 0.001) in the three muscles studied. As might be expected, the curing times from the fresh product to the final product were also significantly different for all the parameters studied in this work. Regarding the inclusion of olive cake, it was found that treatment with a base diet + 10% exhausted olive cake (T4) showed higher levels for the parameters NaCl, collagen, and total fat. As for the fatty acid profile, in general, the olive did not influence the final product. On the other hand, we found that the type of muscle and the curing time of the cured shoulder had a significant influence on the fatty acid profile. We should also point out that there are significant differences in the interaction between curing time and muscle, particularly in saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs), as well as the lipid quality indices. Canonical discriminant analysis is viable for evaluating the evolution of the curing process, discriminating and classifying curing times, and evaluating the muscles of the Bísaro pork shoulder. Also, the introduction of olive cake into the animal diet does not affect the final product obtained.

Chemical, Physicochemical and Sensorial Characterization of Nitrite-Free Dry-Cured Bísaro Shoulders

The aim of the current experiment was to characterize and evaluate the effect of the dry-curing process on chemical composition, physicochemical properties, and sensory characteristics of the dry-cured Bísaro shoulders. For this purpose, thirty-eight raw forelegs were used, and no nitrites were added during the dry-curing process. This process increased protein, fat, ash content, and pH, with a decrease in moisture and water activity (p < 0.001). The dry-cured shoulders were darker (L*), less red (a*), and less yellow (b*) than the raw shoulders (p < 0.001), and this may be mainly due to the moisture reduction. The proportion of polyunsaturated fatty acids (PUFA) decreased during processing, whereas the saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) increased (p < 0.001), which could be related with the oxidative degradation. The sensory analysis showed that dry-cured Bísaro shoulders presented similar organoleptic characteristics to other dry-cured meat products. Also, the chemical composition and fatty acid profile of the dry-cured Bísaro shoulder showed results comparable to those of other cured products. This study revealed that it is possible to obtain safer and healthier dry-cured Bísaro shoulder products judging by these characteristics, since nitrites were not added in its preparation. These findings, along with the product’s high sensory attributes similar to more popular products such as ham, would give more advantage for its acceptability and market demand.