Physicochemical changes during manufacture and final sensory characteristics of dry-cured Celta ham. Effect of muscle type

Technological and sensory characteristics in development of innovative symbiotic boneless dry-cured lamb meat snack

Novel shelf-stable and high-protein meat products that are affordable, convenient, and healthy are hot topic in current food innovation trends. To offer technological databases for developing new functional lamb meat products, this study aimed to evaluate the technological and sensory aspects of dry-cured lamb meat snacks incorporated with the probiotic culture Lactobacillus paracasei and the prebiotic lactulose. Four formulations were analyzed: control (without prebiotic or probiotic); PREB (with 2% lactulose); PROB (with 107 CFU/g of L. paracasei); and SYMB (with 2% lactulose and 107 CFU/g of L. paracasei). Fitted curves revealed that weight-loss behavior during snack ripening was not affected (P > 0.05) by treatments. Snack moisture, water activity, pH, titratable acidity, lipid oxidation, and residual nitrite were affected (P < 0.05) only by ripening time. The target probiotic strain stood out against competitive flora and was detected at 107 CFU/g in the snack-supplemented formulations (PROB and SYMB). In snacks supplemented with prebiotics (PREB and SYMB), the lactulose content was maintained at 2.17%. Significant differences were not observed in the chemical composition, texture profiles, and CIE color indices between the proposed functional snacks and the control. In addition to texture, flavor, and overall impression evaluation, only color attributes were positively impacted (P < 0.05) in the acceptance and multiple comparison tests against the control. The proposed formulation and bench process parameters produced potential nutritionally and sensory-appreciated, microbiologically stable, and safe (multi-hurdle perspective) functional high-protein restructured lamb snacks.

Incorporating Olive By-Products in Bísaro Pig Diets: Effect on Dry-Cured Product Quality

The objective of this study was to assess the impact of incorporating olive cake into the diet of indigenous Bísaro pigs on the quality of processed meat products. To this end, loins and "cachaços" were processed using a standardized manufacturing flowchart to produce dry-cured products. The two products were manufactured using the same formulation, ingredients, and curing process. Concerning the physicochemical composition, there were significant differences between the two products for the parameters of aw (p < 0.001), moisture (p < 0.001), total fat (p < 0.001), protein (p < 0.001), and haem pigments (p < 0.001). The diet significantly impacted the NaCl content (p < 0.05). However, neither the product nor the diet affected the fractions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), or polyunsaturated fatty acids (PUFA) (p > 0.05). However, a significant difference was observed for n-3 (p < 0.05). Adding olive cake increased these fatty acids, and the diet containing 25% centrifuged olive cake showed the highest levels for both products. Compared with the control, the diets containing olive cake had a higher content of n-3 fatty acids, resulting in a lower PUFA n-6/n-3 ratio (p < 0.01).

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.

Revealing the intrinsic relationship between microbial communities and physicochemical properties during ripening of Xuanwei ham

To clarify the relationship between microorganisms and physicochemical indicators of Xuanwei ham. Six ham samples for the first, second and third year were selected, respectively. The changes of physicochemical properties, the free fatty acids and microbial communities of Xuanwei ham were investigated by GC-MS and high-throughput sequencing technology. Results showed that scores of colour, overall acceptability, texture, taste and aroma were the highest in the third year sample. With increasing ripening time, moisture content, water activity (Aw), lightness (L*), springiness, and resilience decreased continuously, and yellowness (b*) was the highest in the second year sample. 31 free fatty acids were detected, and unsaturated fatty acids such as palmitoleic acid, oleic acid, and linoleic acid were the major fatty acids. The content of palmitoleic acid, oleic acid and eicosenoic acid increased significantly during processing. At the phylum level, the dominant bacteria were Proteobacteria and Firmicutes, and fungi were Ascomycota. At the genus level, the dominant bacteria were Staphylococcus and Psychrobacter, and fungi were Aspergillus. Correlation analysis showed that water content and Aw were closely related to microorganisms, and most unsaturated fatty acids were significantly correlated with microorganisms. These findings showed that microorganisms played an important role in the quality of Xuanwei ham, and provided a scientific basis for the quality control of Xuanwei ham.

Effect of Overripening on the Physico-Chemical and Sensory Characteristics of Boneless, Salt-Reduced Iberian Dry-Cured Ham

The aim of this study was to evaluate the effect of extended maturation and temperature increase on the physico-chemical, biochemical, instrumental color and texture, sensory, and acceptability parameters of cured and boneless Iberian hams. Given the limited knowledge in this area, our objective was to develop a ham with enhanced proteolysis, potentially leading to increased bioactive peptide generation and superior sensory characteristics compared to salt-reduced counterparts. To achieve this, a batch of hams cured up to 38% loss at 30 °C and two batches cured up to 42% loss at 30 °C and 36 °C were evaluated. Results showed that the increase in processing time and temperature significantly enhanced (p < 0.05) ham proteolysis and amino acid content without adversely affecting its texture. No significant differences were observed in instrumental texture parameters or sensory attributes as evaluated by consumers. These processing conditions also increased the content of free amino acids, improving the product quality. Overall, these processing modifications resulted in hams with excellent sensory acceptability and enhanced bioactive potential despite the salt reduction.

Insight into the Relationship between the Causes of Off-Odour and Microorganism Communities in Xuanwei Ham

To expound on the correlation between the microorganism communities and the formation of off-odour in Xuanwei ham, the microorganism communities and volatile compounds were investigated in the biceps femoris (BF) and semimembranosus (SM) of Xuanwei ham with different quality grades (normal ham and spoiled ham). The single molecule real-time sequencing showed that differential bacteria and fungi were more varied in normal hams than in spoiled hams. Headspace solid-phase microextraction-gas chromatography (HS-SPME-GC-MS) results indicated that aldehydes and alcohols were significantly higher in spoiled hams than those in normal hams (p < 0.05). The off-odour of spoiled hams was dominated by ichthyic, malodourous, sweaty, putrid, sour, and unpleasant odours produced by compounds such as trimethylamine (SM: 13.05 μg/kg), hexanal (BF: 206.46 μg/kg), octanal (BF: 59.52 μg/kg), methanethiol (SM: 12.85 μg/kg), and valeric acid (BF: 15.08 μg/kg), which are positively correlated with Bacillus cereus, Bacillus subtilis, Bacillus licheniformis, Pseudomonas sp., Aspergillus ruber, and Moraxella osloensis. Furthermore, the physicochemical property and quality characteristics results showed that high moisture (BF: 56.32 g/100 g), pH (BF: 6.63), thiobarbituric acid reactive substances (TBARS) (SM: 1.98 MDA/kg), and low NaCl content (SM: 6.31%) were also responsible for the spoilage of hams with off-odour. This study provided a deep insight into the off-odour of Xuanwei ham from the perspective of microorganism communities and a theoretical basis for improving the flavour and overall quality of Xuanwei hams.

1H NMR Reveals the Mechanism of Potassium Lactate on Proteolysis and Taste Metabolites of Rugao Ham

To deepen the understanding of the effect of potassium lactate on the taste of Rugao ham, proteolysis index, enzyme activities and protein degradation of Rugao ham salted with potassium lactate (0%, 0.5%, 1%, 2%) were investigated. Metabolites of Rugao ham were identified by 1H nuclear magnetic resonance (NMR) spectroscopy and the metabolic pathways of the key metabolites were enriched by the Kyoto Encyclopedia of Genes and Genomes (KEGG); the relationship between taste and metabolites was assessed by partial least square discriminant analysis (PLS-DA). The hams with 2% potassium lactate showed lower cathepsin B and L activities, and higher aminopeptidase activities than that of the control group. The contents of free amino acids and organic acids significantly increased from the control to the treatment of 2% potassium lactate. PLS-DA further demonstrated that aspartate, glutamate, alanine, serine, threonine, acetate, lactate, succinate, carnosine, β-glucose and glycerol were the key metabolites to improve the taste of Rugao ham in the treatment of 2% potassium lactate. Metabolic pathways analysis further demonstrated that amino acids metabolism was the main pathway for the taste development of Rugao ham.

Bioactive and Sensory Di- and Tripeptides Generated during Dry-Curing of Pork Meat

Dry-cured pork products, such as dry-cured ham, undergo an extensive proteolysis during manufacturing process which determines the organoleptic properties of the final product. As a result of endogenous pork muscle endo- and exopeptidases, many medium- and short-chain peptides are released from muscle proteins. Many of them have been isolated, identified, and characterized, and some peptides have been reported to exert relevant bioactivity with potential benefit for human health. However, little attention has been given to di- and tripeptides, which are far less known, although they have received increasing attention in recent years due to their high potential relevance in terms of bioactivity and role in taste development. This review gathers the current knowledge about di- and tripeptides, regarding their bioactivity and sensory properties and focusing on their generation during long-term processing such as dry-cured pork meats.

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.

Effect of Salt Reduction on the Quality of Boneless Dry-Cured Ham from Iberian and White Commercially Crossed Pigs

Iberian dry-cured ham has great value in a traditional Spanish diet, although experts have recommended its consumption should be reduced because of its high salt content and link to cardiovascular diseases. Eighteen boneless Iberian hams (RIB), eighteen boneless white commercially crossed pig hams (RWC), and eighteen traditionally salted and processed Iberian hams (TIB) were manufactured to check whether the breed (RIB vs. RWC) or the processing (RIB vs. TIB) affects their physical–chemical and sensory characteristics. Moisture, protein, total nitrogen, nonprotein nitrogen, proteolysis index, NaCl, and ash contents were higher in RWC, contrary to the fat values, which were more than double in RIB. All macrominerals, except Ca, were affected by the processing stage and breed, whereas only the micromineral Zn was higher in RWC. The breed did not affect the free amino acid content; however, the total content was slightly higher in RWC. Regarding the manufacturing process, the deboning of RIB allowed the reduction of salt by over 30%. However, the microbiological stability was not affected, resulting in a safe product. Although deboning and salt reduction significantly affect the hardness, adhesiveness, deformation, and elasticity of dry-cured hams, consumers value all sensory parameters with higher scores in RIB.

LC-MS/MS-based metabolomics and sensory evaluation characterize metabolites and texture of normal and spoiled dry-cured hams

The spoiled dry-cured ham commonly shows unpleasant taste and odour. To deepen the understanding in the formation mechanism of unpleasant taste in spoiled ham, sensory attributes, texture parameters, protein degradation, metabolites were investigated between normal and spoiled hams; the relationship between the sensory quality and metabolites of dry-cured ham was further evaluated by partial least square discriminant analysis (PLS-DA). The scores of richness and overall acceptance were significantly lower in spoiled ham, and more than 12.5-fold values in adhesiveness were found in spoiled ham than normal ham. Myofibrillar proteins including actin, troponin-T and myosin light chain showed excessive degradation in spoiled ham. Forty-two kinds of metabolites mainly derived from protein degradation were identified by LC-MS/MS, and amino acid derivatives and oligopeptides were the key components to distinguish spoiled and normal hams demonstrated by PLS-DA. Purine metabolism, pyrimidine metabolism and protein degradation were the main metabolism pathways in spoiled ham.

Recent advances in the development of healthier meat products

Meat products are an excellent source of high biological value proteins, in addition to the high content of minerals, vitamins, and bioactive compounds. However, meat products contain compounds that can cause a variety of adverse health effects and pose a serious health threat to humans. In this sense, this chapter will address recent strategies to assist in the development of healthier meat products. The main advances about the reduction of sodium and animal fat in meat products will be presented. In addition, strategies to make the lipid profile of meat products more nutritionally advantageous for human health will also be discussed. Finally, the reduction of substances of safety concern in meat products will be addressed, including phosphates, nitrites, polycyclic aromatic hydrocarbons, heterocyclic aromatic amines, as well as products from lipid and protein oxidation.

Characterization of Umami Dry-Cured Ham-Derived Dipeptide Interaction with Metabotropic Glutamate Receptor (mGluR) by Molecular Docking Simulation

Dry-cured ham-derived dipeptides, generated along a dry-curing process, are of high importance since they play a role in flavor development of dry-cured ham. The objective of this study was to analyze the residues of the less-studied metabotropic glutamate receptor 1 (mGluR1) implicated in the recognition of umami dry-cured ham dipeptides by molecular docking simulation using the AutoDock Suite tool. AH, DA, DG, EE, ES, EV, and VG (and glutamate) were found to attach the enzyme with inhibition constants ranging from 12.32 µM (AH) to 875.75 µM (ES) in the case if Rattus norvegicus mGluR1 and 17.44 µM (VG) to 294.68 µM (DG) in the case of Homo sapiens, in the open–open conformations. Main interactions were done with key receptor residues Tyr74, Ser186, Glu292, and Lys409; and Ser165, Ser186, and Asp318, respectively, for the two receptors in the open–open conformations. However, more residues may be involved in the complex stabilization. Specifically, AH, EE and ES relatively established a higher number of H-bonds, but AH, EV, and VG presented relatively lower Ki values in all cases. The results obtained here could provide information about structure and taste relationships and constitute a theoretical reference for the interactions of novel umami food-derived peptides.

Influence of Muscle Type on Physicochemical Parameters, Lipolysis, Proteolysis, and Volatile Compounds throughout the Processing of Smoked Dry-Cured Ham

The influence of muscle type (biceps femoris, BF and semimembranosus, SM) on physicochemical parameters, volatile compounds, and the extent of proteolysis and lipolysis during the manufacturing of smoked dry-cured ham was investigated. A total of fifty smoked hams were sampled: raw ham, after salting, smoking, drying, and ripening. Almost all physicochemical parameters were affected by muscle type, manufacturing stage and their interactions. SM had lower water, ash, NaCl content, and water activity (aw), while fat and protein content were higher after ripening compared to BF. BF showed higher L*a*b* values compared to SM. The results of texture profile analysis showed that almost all analyzed parameters were influenced by muscle type and production stage. A total of 88 volatile compounds were identified, showing an increase in its number during processing: 31 volatile compounds were identified in raw ham and 72 after the ripening phase. Aldehydes and phenols were the predominant groups of compounds, followed by alcohols, ketones, aromatic hydrocarbons, aliphatic hydrocarbons, esters, and terpenes. Muscle type and production phase significantly affected lipid oxidation and the index of proteolysis: in SM, thiobarbituric acid reactive substances (TBARS) increased faster than in BF, while proteolysis had an opposite effect and was more pronounced in BF.

Proteolysis and protein oxidation throughout the smoked dry-cured ham process

During the five stages of smoked dry-cured ham processing, proteolysis and protein oxidation were simultaneously detected in the Biceps femoris (BF) and Semimembranosus (SM) muscles. Proteolysis was more advanced in BF than in SM throughout the process of production. The total FAA increased significantly (p < 0.05) throughout the processing, resulting in higher total FAA content in BF than in SM muscle. SDS-PAGE revealed progressive degradation of sarcoplasmic proteins of investigated muscles, with the pronounced changes for the 69.9-41.7 kDa region. SDS-PAGE of BF showed more intense degradation of myofibrillar proteins due to greater proteolysis in BF. Electrophoresis of myofibrillar proteins evidenced the marked degradation of 130 kDa, 96.7 kDa and 27-20.7 kDa bands in both muscles. A similar trend was observed for protein oxidation in BF and SM, with the final values of 26.36 and 23.7 nmol carbonyls/mg proteins, respectively. The Pearson correlation revealed a strong relationship between protein oxidation and proteolysis.

Sensory characteristics and volatile compounds of dry cured ham Speck are affected by pig dietary supplementation with antioxidant mixture

BACKGROUND

Dry cured ham named Speck is a typical Italian product, with consolidated processing techniques and specific quality parameters. It has gained importance in the international market after obtaining the Protected Geographical Indication. Recent studies indicate that dietary plant extracts in pig may affect quality of processed meats but there are no data on their effect on Speck. Consequently, the effects of dietary supplementation with antioxidant mixture (AOX), containing vitamin E and polyphenols, in pigs on the nutritional characteristics, volatile compounds, sensory properties and consumers' preference of Speck were evaluated.

RESULTS

The Speck weight loss during seasoning was lower in the AOX group, while products quality parameters were not affected by dietary treatments. Alcohol and terpenes concentrations were lower (P < 0.05) in the AOX samples than the control. Sensory profile revealed slight differences (P < 0.05) in Speck salty and sweet taste, whereas the consumer tests showed a higher (P < 0.05) preference, with mean score of seven, for Speck from pigs fed AOX.

CONCLUSION

Our results provide new insights on the quality parameters of Speck. Dietary integration with antioxidant mixture decreased Speck weight losses during seasoning. Volatile compounds concentrations and sensory profile were slightly affected by dietary treatment. The consumer test revealed that dietary antioxidants, increased the overall preference for Speck, and can potentially increase its consumption. © 2020 Society of Chemical Industry.

Effects of partial NaCl substitution with high-temperature ripening on proteolysis and volatile compounds during process of Chinese dry-cured lamb ham

The effects of partial NaCl substitution combined with high-temperature ripening on the proteolysis and formation of volatile compounds in dry-cured lamb ham was investigated. Two salt treatments, I (0% KCl + 100% NaCl) and II (25% KCl + 75% NaCl), were considered. Although some studies have analyzed the influences of salt substitution on volatile compounds of dry-cured ham, no studies have evaluated lamb ham produced in China. Intensifying the high-temperature ripening lead to an increase in the formation of flavors generated by the Maillard reaction and Strecker degradation in both treatments, also, had a positive influence on proteolysis index and content of total free amino acids during the ripening stage. The application of 25% KCl did not influence the formation of volatiles during curing stage, however, there were more volatiles came from amino acids degradation in the final products with 25% KCl. Therefore, sodium reduction combined with high-temperature ripening may be an alternative method to manufacture Chinese dry-cured lamb hams.

Effectiveness of Sprayed Bioactive Fruit Extracts in Counteracting Protein Oxidation in Lamb Cutlets Subjected to a High-Oxygen MAP

High-oxygen packaging atmosphere (High-Ox-MAP) promotes meat protein oxidation and leads to texture deterioration. This study was conceived to assess the extent to which sprayed fruit extracts could inhibit the oxidative damage to proteins in lamb cutlets subjected to High-Ox-MAP (10 days/4 °C) and subsequent roasting (10 min/180 °C). Extracts from oaknut (Quercus ilex subsp. ballota; QI), rose hips (Rosa canina L.; RC), common hawthorn (Crataegus monogyna Jacq.; CM) and strawberry tree (Arbutus unedo L.; AU) were characterized for bioactive compounds (phenolic subclasses, tocopherols and ascorbic acid) and in vitro bioactivities. While the four fruits showed relevant antioxidant potential, CM had the highest phenolics and tocopherol content and that was reflected in efficient antiradical activity. The in vitro activity of this fruit to inhibit meat protein oxidation was, however, lower than that displayed by the other fruits. Taking the results altogether, CM was also found to be most efficient in protecting lamb cutlets from lipid oxidation. All fruits were able to inhibit thiols oxidation except RC, which seemed to reduce protein thiols. Among fruits, QI was the most efficient in protecting lamb cutlets against protein carbonylation as a plausible involvement of ellagitannins. The inhibition of protein oxidation by QI was reflected in significantly lower instrumental hardness in cooked lamb cutlets. Spraying lamb cutlets with extracts from QI, RC and CM improved consumers' purchase intention after chilled storage. This antioxidant strategy seems to be a feasible and efficient solution to the pro-oxidative effects caused by High-Ox-MAP in red meat.

Low-sodium dry-cured rabbit leg: A novel meat product with healthier properties

Dry-cured rabbit legs were produced with a 50% reduction or replacement of NaCl by KCl and with the addition of monosodium glutamate (MG). The effect of this reformulation on technological, nutritional, and sensory characteristics was evaluated. The sodium reformulation did not show a great impact on Aw, pH, weight loss, and volatile profile of the samples. The samples presented high protein (31.5 to 36.1%) and low fat contents (3.2 to 5.7%). In addition, all essential amino acids presented an amino acid score greater than 1.0. The reformulated samples showed a sodium reduction of 46.2% while the addition of KCl to the formulations provided a healthy Na/K ratio. Oleic acid was the major fatty acid (FA) (31.3% of total FA) and healthy lipid indexes were observed for all samples. Finally, the addition of MG was effective to compensate for the sensory defects caused by sodium reformulation.

Challenges to reduce or replace NaCl by chloride salts in meat products made from whole pieces - a review

NaCl is fundamental for the development of the physico-chemical, sensorial and microbiological stability in meat products made from whole pieces such as dry-cured lacón, loin, ham, bacon, jerked beef, and pastirma). The substitution of NaCl by other chloride salts (KCl, CaCl₂ and MgCl₂), in order to minimize changes in the processing steps and insertion of new ingredients, is a major challenge for the elaboration of salted meat products in the context of increasing awareness among consumer about sodium consumption and health. This review aims to discuss the potential use of binary, ternary and quaternary salting mixtures in the processing of salted meat products and their effects on microbiological evolution and safety, sensory properties, oxidative reactions on proteins and lipid, and proteolysis and lipolysis reactions. More specifically, the substitution of NaCl by other chloride salts can influence the growth of microorganisms, the formation of toxic compounds, progression of enzymatic and oxidative reactions, and the sensory attributes. Scientific evidences from a food technological point of view, support the use of KCl to partially replace NaCl while major advances/more sophisticated strategies are still necessary to effectively introduce CaCl₂ and MgCl₂ as NaCl replacers. Moreover, further studies regarding the shelf-life and economic problems of the alternatively salted products are still necessary.

Effect of pulsed light treatment on Listeria inactivation, sensory quality and oxidation in two varieties of Spanish dry-cured ham

The efficacy of pulsed light (PL) for the surface decontamination of ready-to-eat dry-cured ham was studied in two Spanish varieties, Serrano and Iberian. Listeriainnocua was inoculated on the surface of ham slices that were vacuum-packaged and flashed with 2.1, 4.2 and 8.4 J/cm². Survivors were enumerated immediately after treatment. Peroxide values, sensory analysis and volatile profile were investigated during storage at 4 and 20 °C. Inactivation of Listeria was higher in Iberian (ca. 2 log cfu/cm²) than in Serrano ham (ca. 1 log cfu/cm²) with 8.4 J/cm². PL did not increase the peroxide values above the usual levels reported in dry-cured ham, and no rancid notes were observed in the sensory analysis. PL-treated samples showed an increase in the concentration of some volatile compounds, such as methional, dimethyl disulfide and 1-octen-3-one, which imparted slight sulfur and metallic notes, although they disappeared during storage.

Influence of dietary protein content on the chemico-physical profile of dry-cured hams produced by pigs of two breeds

The use of low-protein (LP) feeds is a good strategy to reduce the environmental release of N compounds, but their influence on the quality of the products must be considered. This study explored the influence of LP diet and two pig breeds (BR) with different lean growth ability on the quality traits of dry-cured hams. We analysed 40 left dry-cured hams from pigs of two BR [Duroc-Danbred crosses (Danbred) and Duroc × Large White crosses (Anas)] fed either conventional (147 to 132 g/kg, crude protein) or LP diet. The LP had a crude protein content reduced by 20% with respect to the conventional. The differences in ham quality resulting from protein reduction were small, with a decrease of the protein and an increase of the lipid content of the ham slice in Anas, but not in Danbred (BR × Diet interaction; P = 0.043). Therefore, the use of LP would be feasible and sustainable, without detrimental effects on products. It was found the pig genotypes with different potentials for lean growth may affect the initial ham weight, fat cover and seasoning losses of hams, but they appear to affect little other chemical, physical and textural quality traits of the dry-cured hams.

Evolution of volatile compounds and physical, chemical and sensory characteristics of Toscano PDO ham from fresh to dry-cured product

Physical and chemical changes in Toscano ham lean were evaluated according to three different seasoning time (14, 16 and 18 months). Moreover, on Semimembranosus muscle, the volatile profile at 0, 1, 3, 6, 12, 14, 16 and 18 months of seasoning was determined by SPME–GC–MS. Eventually, a quantitative-descriptive sensory evaluation was performed. Longer seasoning times led to a decrease of Chroma in Biceps femoris, and also protein and proteolysis index decreased as the seasoning time increased. A total of 97 volatile compounds (VOCs) belonging to seven chemical families (29 aldehydes, 16 esters, 14 alcohols, 13 hydrocarbons, 12 ketones, 10 acids, 2 furans and 1 nitrogenous compound) were identified. Sensory evaluation outlined the major differences between 18th months ham and the other two classes, with the former being harder and with a slight presence of off flavor and off odor. The VOCs evolution during curing was studied and a multivariate approach was performed to test the feasibility of using the VOCs profile to predict the curing stage of Toscano ham. The discriminant analysis successfully managed to separate the samples of 0–6 months from the ones of 12–18 months using 26 of the identified VOCs. Among them, pentane 2,3-dimethyl, acetophenone and 9-decenoic acid were strong discriminants for 0–6 months hams, while dodecanoic, benzeneacetaldehyde, 3-octen-2-one and pentanoic acid ethylester were linked to 12–18 months hams. Within the high maturing classes (12, 14, 16, 18 months of seasoning), the 17 discriminating compounds identified successfully allocated only 12 and 18 months samples. The main VOCs associated with the “12 months” class were nonanal, 1,5-diphenyl-3-methylthio-1,2,4-triazole and 6-methoxy 2-hexanone. The “18 months” seasoning class, instead, was identified by 1,5-diphenyl-3-methylthio-1,2,4-triazole, phenol and l,2-butoxy ethanol.

El Gueddid, a traditional Algerian dried salted meat: Physicochemical, microbiological characteristics and proteolysis intensity during its manufacturing process and ripening

El Gueddid is a traditional salted and dried meat with high popularity in Algeria. It is used as an ingredient in various dishes. In this study, different samples of El Gueddid were analyzed at different processing times to follow up their microbiological and physicochemical properties. Changes in the protein profile were also demonstrated by electrophoretic study of myofibrillar proteins. Microbiological determinations included the total viable count, coliforms, Staphylococci, lactic acid bacteria, yeasts, and molds, whereas physicochemical properties were characterized by pH, moisture, salt content and water activity. The results showed that microbial profiles were elevated for all the studied micro-organisms. Staphylococci and lactic acid bacteria were the most abundant micro-organisms in the product. Total coliforms were found in low numbers in fresh meat, being eliminated at the post salting stage of process. The physicochemical characteristics showed that the moisture content decreased in the product during the drying period. The pH also decreased during the drying period, then remained almost unchanged during the rest of the ripening period. Moreover, El Gueddid showed low water activity and high salt content. One of the most important changes in the profile of myofibrillar proteins was a reduction in the myosin heavy chain content.

Proteomic footprint of ultrasound intensification on sliced dry-cured ham subjected to mild thermal conditions

Ultrasound can intensify the heating process used to correct texture defects in dry-cured hams. The effect of ultrasound-assisted heating on the proteome of sliced dry-cured ham was evaluated. Dry-cured hams with high proteolysis index (PI > 36) were sliced, vacuum packed and subjected to conventional (CV) and ultrasound-assisted (US) thermal treatments. Comparative proteome profiling between sample groups was assessed by two-dimensional electrophoresis (2-DE) coupled to tandem mass spectrometry. It was found that protein fragmentation increased markedly after US thermal treatment. Specifically, fragments of the major myofibrillar protein, actin, were abundantly over-represented following US heating. In addition, five unfragmented sarcoplasmic proteins (i.e. fatty acid-binding protein, peroxiredoxin-6, superoxide dismutase, carbonyl reductase and aminoacylase) showed increased abundance in the US sample group. These results suggest candidate biomarkers to monitor proteolysis intensity and proteolysis-independent effects linked to cured ham quality by ultrasound application. SIGNIFICANCE: The present proteome profiling study of treated dry-cured ham demonstrates the impact of ultrasound action on proteins. Moreover, negative organoleptic effects can be appearing with ultrasound treatment due to proteolysis increase. Therefore, the proteolysis monitoring could help to control these effects. In this regards, our results suggest that actin can be a candidate biomarker to monitor proteolysis intensity.

Application of temperature and ultrasound as corrective measures to decrease the adhesiveness in dry-cured ham. Influence on free amino acid and volatile compound profile

The impact of low temperature treatment and its combination with ultrasound has been evaluated in order to correct texture defects in dry-cured hams. A total of 26 dry-cured hams, classified as high proteolysis index (PI>36%), were used. From these hams, ten slices from each ham sample were cut, vacuum packed and submitted to three different treatments: control (without treatment), conventional thermal treatments (CV) and thermal treatment assisted by power ultrasound (US). The impact of these treatments on instrumental adhesiveness, free amino acid and volatile compounds profile were assessed. Statistical analysis showed that both US and CV treatments, significantly (P < .001) decreased the instrumental adhesiveness of dry-cured hams from 85.27 g for CO to 40.59 and 38.68 g for US and CV groups, respectively. The total free amino acid content was significantly (P < .001) affected by both treatments, presenting higher values the samples from the US group (6691.5 vs. 6067.5 vs. 5278.2 mg/100 g dry matter for US, CV and CO groups, respectively). No significant differences were observed between US and CV treatments. All the individual free amino acids were influenced by ultrasound and temperature treatments, showing the highest content in sliced dry-cured ham submitted to ultrasounds at 50 °C, except for isoleucine which presented the highest level in samples from CV group. Similarly, significant differences (P < .05) were also detected in the total volatile compound content between CO and US groups, with a higher concentration in the CO batch (56,662.84 AU × 10³/g of dry-cured ham) than in the US treatment (45,848.47 AU × 10³/g of dry-cured ham), being the values in the CV treatment intermediate (48,497.25 AU × 10³/g of dry-cured ham). Aldehydes, ethers and esters, carboxylic acids and sulphur compounds were more abundant in the CO group, while CV group showed higher concentrations of ketones, alcohols and nitrogen compounds.

Physicochemical changes of semimembranosus muscle during the processing of dry-cured ham from Celta pig. Effect of crossbreeding with Duroc and Landrace genotypes

Physicochemical characteristics of dry-cured hams from three genetic types, Celta breed (C line), Celta × Duroc (C × D) and Celta × Landrace (C × L) were determined on the semimembranosus muscle during 551 days of aging. Hams were obtained from 60 pigs reared in extensive systems and finished with a commercial feeding. Physicochemical parameters (pH and water activity) and chemical composition, (moisture, intramuscular fat, ash, protein and total chlorides content), colour parameters (L*, a* and b*) and lipid oxidation (thiobarbituric acid reactive substances value) were studied during the whole process after salting, post-salting, drying and bodega stages. Hams from crosses were characterised by higher intramuscular fat (12.78% and 10.48% for C × D and C × L lines, respectively) and moisture (46.86% and 46.63% for C × D and C × L genotypes, respectively), contents respect to Celta pure line that showed values of 5.96% and 35.83% for intramuscular fat and water content, respectively. Concerning colour parameters, hams from Celta line had lower values for all colour traits. The influence of crossbreeding on most physicochemical parameters observed was mainly due to the differences in moisture and intramuscular fat between hams obtained from pure breed and crosses. As a general conclusion, the crossbreeding of Celta pig (especially with the Duroc line) allows to improve the quality of dry-cured hams.

Caracterização física, química e microbiológica de presunto cru desossado adicionado de lactulose

Resumo Objetivou-se o desenvolvimento e caracterização tecnológica e microbiológica de presunto cru desossado contendo lactulose como prebiótico. Os presuntos foram elaborados utilizando-se a transglutaminase como agente ligante e glucona-delta-lactona como acidulante, sendo avaliadas uma formulação controle e outra com adição de 2% de lactulose (LAC). Ambos os produtos obtidos atenderam aos padrões físico-químicos e microbiológicos determinados na legislação brasileira para presuntos crus. A perda de massa na etapa de secagem foi maior (P < 0,05) nos produtos adicionados de lactulose do que no controle. Não foram encontradas diferenças significativas (P > 0,05) entre os tratamentos para os parâmetros avaliados durante o processamento, com os valores de umidade, atividade de água (aw) e nitrito residual reduzindo-se (P < 0,05) e os valores de acidez, bactérias ácido-lática e índice de TBARS aumentando (P < 0,05) com a maturação. Os produtos elaborados apresentaram pH (5,55 ± 0,37) e aw (0,90 ± 0,01) condizentes com produtos curados dessecados, não havendo (P > 0,05) diferenças entre os tratamentos para a composição centesimal e a cor final dos produtos. O teor de lactulose no produto LAC foi de 1,44% ± 0,37%, o que indica a viabilidade da utilização desse prebiótico na elaboração de presuntos crus desossados com vistas à alegação de produto com propriedade funcional.

Effects of Whey Powder Supplementation on Dry-Aged Meat Quality

The objective of this study was to determine the effect of dietary supplementation with whey powder (WP, 1g/kg feed) from weaning to slaughter (150 d) on dry-aged loin quality of pigs. Fifty-eight pigs were randomly divided into two dietary treatment groups (seven replications of four pigs per treatments). Basal diet with 0.1% whey powder was supplied to the WP group. Basal diet was used for the control group (CON). Diet whey protein did not appear to influence the moisture or protein contents. However, ash and fat contents were significantly (p<0.05) decreased in the WP group compared to the control group. Drip loss was significantly (p<0.05) lower in the WP group than that of the control group. Increasing redness with decreasing lightness was found in the inner loin of the WP group. Calcium and iron contents in the WP group were significantly higher than those in the control group. Protein degradation was higher in the WP group than that in the control group (p<0.05), whereas shear force was lower in the WP group than that in the control group (p<0.05). In conclusion, the basal diet supplemented with 0.1% whey powder influence negatively the lipid oxidation of meat whereas the texture property and mineral composition of meat from whey powder fed pigs are developed.

Effect of Dietary Processed Sulfur Supplementation on Texture Quality, Color and Mineral Status of Dry-cured Ham

This study was performed to investigate the chemical composition, mineral status, oxidative stability, and texture attributes of dry-cured ham from pigs fed processed sulfur (S, 1 g/kg feed), and from those fed a basal diet (CON), during the period from weaning to slaughter (174 d). Total collagen content and soluble collagen of the S group was significantly higher than that of the control group (p<0.05). The pH of the S group was significantly higher than that of the control group, whereas the S group had a lower expressible drip compared to the control group. The S group also showed the lower lightness compared to the control group (p<0.05). In regard to the mineral status, the S group had significantly lower Fe(2+) and Ca(2+) content than the control group (p<0.05), whereas the proteolysis index of the S group was significantly increased compared to the control group (p<0.05). The feeding of processed sulfur to pigs led to increased oxidative stability, related to lipids and pigments, in the dry-cured ham (p<0.05). Compared to the dry-cured ham from the control group, that from the S group exhibited lower springiness and gumminess; these results suggest that feeding processed sulfur to pigs can improve the quality of the texture and enhance the oxidative stability of dry-cured ham.

A polymorphism in the stearoyl-CoA desaturase gene promoter increases monounsaturated fatty acid content in dry-cured ham

Data on 125 dry-cured hams from purebred Duroc pigs were used to examine whether the favorable effect of the T allele in the promoter region of the stearoyl-CoA desaturase gene (AY487830:g.2228T>C) on monounsaturated fatty acid (MUFA) content in green ham is maintained after the curing process. It is shown that pigs carrying the T allele produced dry-cured hams with increased C16:1, C18:1n-9, C18:1n-7, and MUFA and decreased C18:0 and saturated fatty acid (SFA) content. The TT pigs had 1.39% more MUFA and 1.62% less SFA than the CC animals, while gilts had 0.74% more MUFA and 0.34% less SFA than barrows. The correlation between MUFA in green and dry-cured hams (n=53) was high (r=0.88), with TT pigs being more effective in retaining increased MUFA in green hams until the end of the curing period. It is concluded that increasing the presence of the T allele could have more impact than gender to produce hams with a high level of MUFA.

Influence of type of muscle on volatile compounds throughout the manufacture of Celta dry-cured ham

The effect of muscle type on volatile compounds throughout the manufacture of Celta dry-cured ham was studied. Thirty Celta ham were taken from the fresh pieces, after the end of the salting stage, after 120 days of post-salting, after the end of drying-ripening stage, and after 165 and 330 days of "bodega" step. The volatile compounds from semimembranosus (SM) and biceps femoris (BF) muscles were extracted by using headspace-solid phase microextraction (SPME) and analysed by gas chromatographic/mass spectrometry (GC/MS). Fifty-five volatile compounds were identified and quantified. The number of volatile compounds increased during the different steps of the process, reaching at 550 days of process 39 and 40 volatile compounds in SM and BF muscles, respectively. Results indicated that the most abundant chemical family in flavour at the end of the manufacturing process were esters in the two muscles studied, followed by aliphatic hydrocarbons and aldehydes. During the manufacturing process, an increase in the total amount of volatile compounds was observed, being this increase more marked in samples from BF muscle (from 550.7 to 1118.9 × 10(6) area units) than in samples from SM muscle (from 459.3 to 760.4 × 10(6) area units). Finally, muscle type displayed significant (P < 0.05) differences for four esters, two alcohols, one aldehyde, one ketone and four aliphatic hydrocarbons.