Dry-cured Shoulders Research Articles

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.

Efficacy of modified active packaging with oxygen scavengers for the preservation of sliced Iberian dry-cured shoulder.

The effectiveness of commercial oxygen scavengers was investigated in order to increase the shelf-life of sliced dry-cured Iberian shoulder in MAP (modified atmosphere packaging) for up to 150 days. Five dry-cured shoulders from Iberian pigs were used. Slices of these dry-cured shoulders were randomly packaged in MAP conditions. An active packaging (AP) with oxygen scavengers was evaluated to reduce the level of oxygen within the headspace as close to 0% as possible. AP was compared to a Control Treatment (C) (without scavenger). Sliced dry-cured Iberian shoulder in AP showed lower thiobarbituric acid reactive substances values (TBARS) than control packages after 150 days of storage, and in general, volatile compounds derived from lipid oxidation, increased in C packages, whereas these remained steady in AP. Therefore, AP was effective to decrease the development of lipid oxidation during storage. In contrast, AP was not effective in preserving color changes, although no sensory differences between treatments were appreciated by the panelists.

Effects of genotypes and crossbreeding on the quality parameters of dry-cured shoulders from different Iberian genetic pig lines

Iberian pigs are a porcine breed, in which is very important to obtain a genetic line showing a larger prolificacy and performance of valuable parts, without affecting the meat quality. The main objective of this work was to estimate genetic and crossbreeding effects on quality parameters on dry-cured Iberian shoulders from the different genotypes of the Iberian pigs. For that, three Iberian pigs’ varieties (Entrepelado, Retinto and Torbiscal) and their reciprocal crosses were used. Thus, three genetic lines showed the best results: (i) the Retinto genetic line (R×R) showed the results with the highest mean values in MUFA (56.02%) and the lowest in salt content (3.12%), which could have a useful genetic basis for the improvement; (ii) the crossed genetic line between Torbiscal and Entrepelado (T×E) is characterized for a high value of myoglobin (9.05 mg/g) that it is related to some sensory attributes (flavor persistence − 5.82- and juiciness − 6.02-); (iii) the crossed genetic line between Retinto and Entrepelado (R×E) is characterized for a high content of lipids (8.32%), which is related to high scores on some sensory attributes (fat oiliness − 6.64-, juiciness − 6.24- and odour intensity − 6.86-). Therefore, these three genetic lines of Iberian pig based on terms of quality are adequate to produce meat and meat products from the Iberian pigs, outstanding R×R genetic line of Iberian pig.

Effect of the genetic line and oleic acid-enriched mixed diets on the subcutaneous fatty acid composition and sensory characteristics of dry-cured shoulders from Iberian pig

The aim of this study was to research the effect of the genetic background (Retinto, Torbiscal, and their reciprocal crosses) on the subcutaneous fatty acids and the sensory characteristics of dry-cured shoulders from Iberian pig, and also to investigate whether there is some interaction between genotype and diet composition when pigs are reared indoors, to obtain information to improve the selection strategies for purebred Iberian pig. The genetic background affected both the fatty acid composition (C17:0, C17:1 n-7, C18:3 n-3 and C20:0 were significantly different) and the sensory characteristics (marbling, lean fibrousness, and flavour intensity and persistence were significantly influenced), which indicates that they should be taken into account in the selection strategies for purebred Iberian pig. In a similar way, the genotype × diet composition interaction also should be taken into account when selecting a genetic line or cross to be fed indoors on a particular diet because of its repercussion on the sensory characteristics.

Determining Mandatory Nutritional Parameters for Iberian Meat Products Using a New Method Based on Near Infra-Red Reflectance Spectroscopy and Data Mining

The new regulation about mandatory labelling on nutrition requires the declaration of specific parameters: protein, lipid, salt and carbohydrate contents. This study reports a fast, accurate method to determine the values of these mandatory nutritional parameters based on near infra-red reflectance spectroscopy (NIRs) technology and data mining techniques, used in an automatic way. For that, two batches of different Iberian pork meat products (dry-cured ham, dry-cured loin, dry-cured shoulder, dry-fermented Salchichon sausage, and dry-fermented Chorizo sausage were used. One batch of each product was used to train the method and the remaining batch was used for validation. To develop the method, prediction equations were obtained from the NIRs, while nutritional data for the training batches were obtained by applying data mining techniques, and the prediction equations were evaluated against the NIRs data from the validation batch. The prediction equations achieved from very good to excellent degrees of relationship (R > 0.75) and accurate results (MAE 0.75). This new method is rapid, as it takes around 10 minutes in comparison with traditional methods that take around 6 days.

Immune-spaying as an alternative to surgical spaying in Iberian x Duroc females: Effect on the sensory traits and volatile organic compound profile of dry-cured shoulders and dry-cured loins

The aim of this study was to assess the effect of immune-spaying on sensory characteristics and the volatile organic compound (VOC) profile of dry-cured shoulders and loins by comparing Iberian × Duroc surgically spayed females, immune-spayed females and entire females. VOC profile of dry-cured shoulders was not significantly affected by the reproductive status, probably due to the large heterogeneity of dry-cured shoulders as a product. Correspondingly, dry-cured shoulders showed little differences among treatment groups, with better scores for marbling, hardness and chewiness attributes in the immune-spayed females. Dry-cured loin sensory traits such as brightness, marbling, chewiness and juiciness, presented better scores in immune-spayed females. Moreover, dry-cured loins showed a higher homogeneity that allowed the effects of spaying to be observed, thus the Principal Component Analysis performed on VOC profile data indicated a better separation of samples among treatment groups. Consequently, immune-spaying could be a viable alternative to surgical spaying from the point of view of meat quality.

Evaluación de la calidad de las paletas curados de diferentes líneas genéticas de cerdos Ibéricos

In this work the comparative quality of dry cured shoulders was studied from different genetic lines: Retinto x Entrepelado RxT (n=6), Torbiscal TxT (n=6), Entrepelado ExE (n=10), Retinto RxR (n=6) and Entrepelado x Torbiscal TxE/ExT (n=8). Dry-cured shoulders were evaluated w1tr EVACAL method, an original method from SiPA. This method includes physico-chemical analys1s (moisture, intramuscular fat, proteins, NaCI, myoglobin, fatty acid profile, volatile compound s and lipid oxidation), instrumental analysis (instrumental colour, pH and texture) and sensory analysis. The obtained results exposed that RxR batch shows a higher ratio in oleic/steric and MUFAISAT, which is related with a high quality. This was confirmed in the sensory analysis with high scores of fat fluidity and lean brightness. The TxE/ExT batch is characterized by high quantities of myoglobin which resulted in high quantities of volatile compounds from aminoacid (2-metylbutanal y 3-metylbutan al). These facts were shown in the sensory analysis results with higher flavour persistence and higher juiciness in comparison with the other batches. Moreover, RxE batch reveals a high quantity oi intramuscular fat and higher scores in sensory attributes regarding the appearance (fat fluidity), texture (juiciness) and odour intensity in comparison with the other batches. We can conclude that there are three genetics lines which result in high quality products. The convenience of using one of these depends on other aspects like the prolificacy.

Verificación racial de jamones y paletas Ibéricos comercializados en supermercados españoles

The commercialization of Iberian meat and dry-cured products is regulated by the Spanish law. A first decree approved on 2007 (Real Decreto 1469/2007) established that Iberian products designated as “Iberian” have to come from pigs with at least a 50% of their genome from Iberian breed and the remaining percentage from Duroc. This decree was modified on 2014 (Real Decreto 4/2014) and it requires that, to be labelled as “100% Iberian”, products must come from purebred pigs and maintains the previous regulation about “Iberian” label. A traceability SNP chip containing 64 SNPs was developed by the Pig Breeding and Genetics Group of INIA. It allows discriminating between the proportion of Iberian and Duroc genomes of an individual. The objective of this study was to check if the dry-cured products (hams and shoulders) sold as “Iberian” by some of the major distributors of Iberian products at main Spanish supermarkets follow the law. One hundred and sixteen samples of dry-cured ham and shoulder sliced packs commercialized as “Iberian” were genotyped with the chip. The genotyping data was analysed using BAPS 5.3. A percentage of Iberian genome lower than 40% was estimated for 34.5% of the samples, which do not follow the regulation of genetic origin. It is worth to note that five of the 116 samples were 100% Duroc. None of the suppliers included in the study met the law strictly. These results show that, in general, the Quality Standard has not been obeyed for a long time. A future new sampling will show if the stricter controls of the animals set by the 2014 law has been useful to improve the legal compliance.

Active packaging using an olive leaf extract and high pressure processing for the preservation of sliced dry-cured shoulders from Iberian pigs

Abstract The effect of an active packaging (AP) based on olive leaf extract and/or high pressure processing (HPP) was evaluated for the preservation of sliced Iberian dry-cured shoulders during storage. Shoulders came from Iberian pigs (100%) reared outdoors in the Dehesa and fed with acorns and pasture. Dry-cured shoulders were sliced and vacuum packaged in an active packaging with olive leaf extract. HPP at 600 MPa for 7 min was applied to packages and microbiological, color, oxidative and sensory changes were evaluated during 150 days of refrigerated storage. High reductions of microbial counts were found after HPP and the subsequent storage. Instrumental color parameters of dry-cured shoulder were similar in control and AP and/or HPP, and values were stable during storage. Neither AP and/nor HPP modified lipid oxidation values; and during refrigerated storage similar increases of TBA-RS were found in all treatments. Protein oxidation did not show significant differences among treatments, however, protein oxidation was not modified during storage. Most sensory parameters (appearance, taste, flavor and texture) did not show significant differences due to AP and/or HPP. Therefore, AP with olive leaf extract was not effective to preserve sliced dry-cured shoulder alone or combined with HPP. HPP was effective to decrease microbial counts, also, oxidative, color and sensory parameters were not affected after processing and after 150 days of refrigerated storage. Likely oxidative characteristics of shoulders from pigs reared outdoors would be partly responsible of the high stability of this product during processing and storage. Industrial relevance The demand of sliced dry-cured Iberian ham has importantly increased in the last years. During the slicing and packaging, the shelf-life and the safety of the hamcan be reduced. Industrial sector demands new methods to prolong the shelf-life and maintain the original quality of sliced ham during storage. The utilization of an active packaging with antioxidant and antimicrobial properties could increase the shelf-life of this product. Hydrostatic high pressure processing is a non-thermal food processing technology which allows the inactivation of pathogens. The combined effect of both methods (processing and packaging) could improve the antimicrobial effect while preserve the quality after processing to enhance the shelf-life of the product.

Survival of Streptococcus suis, Streptococcus dysgalactiae and Trueperella pyogenes in dry-cured Iberian pork shoulders and loins

Dry-cured hams, shoulders and loins of Iberian pigs are highly appreciated in national and international markets. Salting, additive addition and dehydration are the main strategies to produce these ready-to-eat products. Although the dry curing process is known to reduce the load of well-known food borne pathogens, studies evaluating the viability of other microorganisms in contaminated pork have not been performed. In this work, the efficacy of the dry curing process to eliminate three swine pathogens associated with pork carcass condemnation, Streptococcus suis, Streptococcus dysgalactiae and Trueperella pyogenes, was evaluated. Results of this study highlight that the dry curing process is a suitable method to obtain safe ready-to-eat products free of these microorganisms. Although salting of dry-cured shoulders had a moderate bactericidal effect, results of this study suggest that drying and ripening were the most important stages to obtain dry-cured products free of these microorganisms.

Immune-spaying as an alternative to surgical spaying in Iberian × Duroc females: Effect on the VOC profile of dry-cured shoulders and dry-cured loins as detected by PTR-ToF-MS

Immunocastration in pigs has been proposed as a cruelty-free alternative to surgical castration. In this work the effect of immune-spaying of female pigs on the volatile compound profile of Iberian dry-cured products was evaluated. The head-space volatile compound of dry-cured shoulders and loins from surgically spayed, immune-spayed and entire Iberian×Duroc females was characterized by proton transfer reaction-time of flight-mass spectrometry. It was not possible to identify a significant effect of the castration modality on dry-cured shoulders, probably because of the heterogeneity of samples. Contrarily, Principal Component Analysis of dry-cured loins indicates a better homogeneity of samples and the separation of loins from surgically spayed and immune-spayed females. Some mass peaks tentatively identified as important flavor compounds in dry-cured products, 3-methylbutanal, 2,3-butanedione and 3-methylbutanoic acid, were significantly higher in the immune-spayed females. Therefore, immune-spaying seems to have a negligible effect on the volatile compound profile of dry-cured shoulders, whereas it could affect the VOC profile in the case of dry-cured loins.

Immune-spaying as an alternative to surgical spaying in Iberian × Duroc females: Effect on quality characteristics and fatty acid profile in dry-cured shoulders and loins

The aim of this study was to assess the effect of immune-spaying on meat quality characteristics and fatty acid profile of dry-cured shoulders and loins by comparing Iberian×Duroc surgically spayed females, immune-spayed females and entire females. There were no significant differences on the physicochemical composition of dry-cured shoulders; however the intramuscular fat content of dry-cured loins was higher in immune-spayed females than entire ones, but not significantly different from spayed females. Immune-spayed females showed the highest values, which could improve the sensory quality of Iberian dry-cured loins, since it is considered an index of high quality. On the other hand, the PUFA content of both dry-cured shoulders and loins proved to be lower in immune-spayed than spayed females, which could prevent excessive fat oxidation responsible for rancidity. Therefore, immune-spaying could be a viable alternative to surgical spaying from the meat quality point of view.

Quantification ofγ- andα-tocopherol isomers in combination with pattern recognition model as a tool for differentiating dry-cured shoulders of Iberian pigs raised on different feeding systems

Quantification of γ- and α-tocopherol in dry-cured shoulders of Iberian pigs was evaluated as a tool for differentiating feeding backgrounds or regimens. Samples (n = 115) were obtained over two different seasons from the four categories of pigs described in the Industry Quality Policy, i.e. pigs fed in free-range conditions (FREE-RANGE), pigs fed in free-range conditions and provided feed supplements (FREE-FEED), pigs fed outdoors with feed and with access to grass (FEED-OUT) and pigs fed in intensive conditions with feed (FEED). Linear discriminant functions were calculated and validated. The validation results showed that 20% of the muscle samples were not correctly classified into the four feeding categories, giving an 80% success rate. The FEED group had the lowest proportion of errors, with 100% of samples correctly classified. For the FREE-RANGE group, 87% of samples were assigned to the correct feeding system by cross-validation; however, 13% were considered as FREE-FEED. A higher rate of correct classification can be obtained when using three categories or by calculating the weight gain in free-range conditions using regression equations. Taking into account the high variability of the samples and the high success in classification, these results are of interest and may be applied in practical situations.

Quality of Dry‐Cured Ham Compared with Quality of Dry‐Cured Shoulder

The physicochemical and sensory properties of 30 dry-cured hams and 30 dry-cured shoulders were analyzed to determine the relationships between them. The variables used to characterize both products were: compositional parameters, instrumental texture, amino acid and fatty acid composition, and sensory profile. Despite being products from the same animal and composed mainly of fat, lean, and bone, their morphological differences determine the conditions of the processing time, which produced differences between products in most of the parameters evaluated. Dry-cured shoulders showed lower moisture content and greater instrumental hardness due to their morphology and muscular structure. Besides, these samples showed lower amino acid content according to the shorter ripening time. For the same reason, the dry-cured hams showed higher moisture content, lower instrumental hardness, and higher amino acid content. However, the differences in the muscular structure did not affect the sensory characteristics, which were more related with some compositional parameters, such as chloride, moisture, and amino acid content and with the length of the curing process.

Amino acid and nucleotide contents and sensory traits of dry-cured products from pigs with different genotypes

The free amino acid and nucleotide contents of dry-cured ham, shoulder and loin from two genetic lines selected from pigs according to the paternal allele (homozygous AA and heterozygous AG) of the insulin-like growth factor-II gene were studied by HPLC. Their influence on the flavor and taste characteristics was also studied. The increase of lean content caused by the IGF-II mutation could affect proteolysis during the ripening process and therefore the sensory characteristics. The lower intramuscular fat content in the AA ham batch had a positive effect on the free amino acid content. However, similar flavor traits between ham batches were found, but the AG loin batch showed greater value. The enhancing effect of the IMP on the overall flavor intensity was limited by the amino acid and the IMF contents in dry-cured ham and loin, while in dry-cured shoulder, the IMP could be the reason for the significant differences in after taste and cured flavor scores.

Chemical-instrumental-sensory parameters and chemometrics as tools to discriminate among the quality categories of dry-cured Iberian shoulder

A combination of physico-chemical and sensory measurements along with chemometric tools was used to authenticate the quality category of dry-cured Iberian shoulder. Depending on the confinement regime and feeding background, dry-cured Iberian shoulders from three classes were analyzed: i) pigs reared in confinement regime and fed with commercial feeds (CON class), ii) pigs reared in extensive regime and fed with commercial feeds (EXT class) and iii) pigs reared in extensive regime and fed with natural sources (grass and acorns), called Montanera regime (MON class). The principal component analysis (PCA) results discriminated among the three types of dry-cured shoulders according to their quality. The soft independent modelling of class analogy (SIMCA), which is a classification model, enabled the characterization of the quality class of unknown dry-cured shoulder samples. Finally the Cooman´s plot and Si vs. Hi plot provide a classification for the unknown quality of dry-cured shoulders.

Fatty acid analysis of subcutaneous fat from animals with a reliable and safe feeding

Iberian pig fat characteristics depend on the type of feeding at the end of its finish-fattening period. The routine analysis to differentiate among the qualities of the feeding types given to the pigs in the fattening stage has been the use of fatty acid profiles by gas chromatography. Due to de doubts about the effectiveness of this analysis in the montanera period, the aim of this global study was to test the validity of various analytical methods to determine the feeding type of Iberian pigs, focusing on the fatty acid profile. Three montanera periods with a total of 749 samples from 38 batches have been studied; using a total of 144 dry-cured shoulder shanks, 99 of which are of known pig origin. Results showed that the determination of the fatty acid profile using gas chromatography is not a consistent method to classify the animals according to diet in the recebo category, although it provided good percentages of success for classifying the bellota and cebo categories.

Effect of IGF-II (insulin-like growth factor-II) genotype on the quality of dry-cured hams and shoulders

The aim of this study was to investigate the effect of the paternal allele (homozygous AA and heterozygous AG) of the IGF-II gene on the fat content, fatty acid composition and sensory characteristics of dry-cured hams and shoulders. The effects were more evident in the subcutaneous fat thickness than in the intramuscular fat (IMF) content, and in the dry-cured hams rather than the dry-cured shoulders. Subcutaneous fat thickness was significantly higher in AG dry-cured hams and shoulders; however, IMF content was only significantly higher in AG dry-cured hams. These effects produce changes in fatty acid composition and sensory characteristics when comparing both batches of each product, but the behavior differed with the type of product. Sensory characteristics were similar in both batches of dry-cured hams in spite of the differences in IMF content. Nevertheless, AG dry-cured shoulders showed higher scores in most of the attributes evaluated, despite the IMF content being similar between batches.

Physicochemical and sensory properties of irradiated dry-cured ham

To determine the effect of different irradiation doses on ready-to-eat (RTE) dry-cured shoulder hams, physicochemical and sensory attributes were analyzed during 8 weeks of refrigerated storage. The results show that irradiation reduced the redness value and increased the 2-thiobarbituric acid-reactive substance (TBARS) value as well as the irradiation aroma during storage. However, ham samples irradiated with 2.5 and 5.0 kGy did not show significant changes in lightness values compared to the control sample during 8 weeks of storage. TBARS values were lower in the sample irradiated with 2.5 kGy than in the other irradiated samples. The total plate counts of the 5.0 kGy-irradiated samples were not measured after 0 weeks. Sensory panels found that the 2.5- and 5.0 kGy-irradiated samples had better overall acceptability scores than the other irradiated samples. It was concluded that treatments with lower levels of irradiation (≤5.0 kGy) can enhance the microbial safety and sensory acceptance of dry-cured shoulder hams.