Dry-cured Meat Products Research Articles

O.476 Antibiotics in surgery of fronto-orbito-ethmoidal region

The aim of the study was to investigate OTA contamination of “Slavonski Kulen” during a six-month production process. Raw meat & spices (n = 7) used with the production and final products with either intact or damaged casings (n = 99) were sampled on the production day 30, 60, 90, 120, 150 and 180, and analysed for OTA presence using an enzyme-linked immunosorbent assay (ELISA) and high performance liquid chromatography with fluorescence detection (HPLC-FLD). No statistically significant differences (p > 0.05) were observed among the intact samples on any above-given production day, the maximal OTA value attributable to raw material contamination thereby being 3.18 μg/kg. As for the damaged samples, the mean OTA concentration established on the production day 180 was 7.92 ± 6.50 μg/kg, while the maximal observed OTA value equalled to 17.0 μg/kg. The results demonstrated that casing damaging witnessed during a long-term dry-cured meat products' ripening can result in OTA entry from the surface into the product, causing a significant OTA contamination.

Changes in Fatty Acid Composition of two Muscles from Three Different Iberian × Duroc Genotypes After Refrigerated Storage

The changes of the fatty acid (FA) profile of 2 muscles Longissimus dorsi and Biceps femoris from 3 Iberian × Duroc genotypes were studied: GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. GEN1 and GEN2 are reciprocal crosses while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype Duroc1 was selected for the production of dry-cured meat products while the genotype Duroc2 was selected for meat production. Longissimus dorsi and Biceps femoris BF from the reciprocal cross showed similar changes in FAs profile after refrigerated storage. However, the Duroc sire line affected the FA profiles of intramuscular fat (IMF) and lipid fractions since some differences were found between GEN2 and GEN3. Meat from GEN3 had the highest level of polyunsaturated fatty acids (PUFA) in IMF and lipid fractions as well as the lowest rate of plasmalogens in polar lipid fraction. After storage, meat from GEN3 showed an increase of long chain PUFA in free fatty acids fraction and the highest increase in the ratio DMA/FA [(dimethylacetals/FAs) × 100] after the refrigerated storage, which was indicative of a higher deterioration of this genotype. Therefore, the crossbreeding of Iberian pigs with Duroc selected genotypes (Duroc2) could affect the changes in the FAs profile of meat under refrigerated storage.

Biochemical characteristics of dry-cured lacón (a Spanish traditional meat product) throughout the manufacture, and sensorial properties of the final product. Effect of some additives

The gross composition, the main physicochemical parameters, the proteolytic changes and the characteristics of the fat throughout the manufacture process, and the sensorial characteristics of the final product, were studied in dry-cured lacón, a traditional dry-salted and ripened meat product made in the north-west of Spain from the fore leg of the pig following a similar technological process to that of dry-cured ham. The effect of the use of additives (glucose, sodium nitrite, sodium nitrate, sodium ascorbate and sodium citrate) was also studied. In comparison with other dry-cured meat products made from whole meat pieces, dry-cured lacón is characterised by the low moisture contents, the high pH values, and the low transformation of the pigments. The proteolytic and lipolytic processes throughout the manufacture of this product were not intense. Except for the total carbohydrate and nitrate contents, and the percentage of transformation of the pigments, which were significantly ( P < 0.05) higher in the batches processed with additives, the use of additives did not influence the biochemical modifications that occur throughout the manufacture process of the dry-cured lacón. Regarding the sensorial characteristics, the use of additives seems to improve the colour and the odour of the final product.

Effect of Physico-chemical Characteristics of Raw Muscles from Three Iberian × Duroc Genotypes on Dry-cured Meat Products Quality

The effect of raw material characteristics (longissimus dorsi and biceps femoris) on dry-cured loin and ham quality from three different Iberian · Duroc genotypes was studied: GEN1: ♂ Iberian · ♀ Duroc1, GEN2: ♂ Duroc1 · ♀ Iberian; GEN3: ♂ Duroc2 · ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The line Duroc1 (DU1) was selected for the manufacture of dry-cured meat products, whereas the line Duroc2 (DU2) was selected for meat production with low carcass fat. Raw material and dry-cured meat products did not differ between reciprocal crosses (GEN1 vs. GEN2). However, the genotype of the Duroc sire line affected the quality of meat and dry-cured meat products. GEN1 and GEN2 had higher adipogenic nature and higher postmortem pH than GEN3, and as a result, these dry-cured meat products had better instrumental and sensory quality than those from GEN3. By contrast, meat from GEN3 had lower pH, fat content, and oxidative stability which decreased the quality of dry-cured meat products. Therefore, there was a close connection between raw material and dry-cured meat products quality as it was affected by characteristics related to the genotype such as the adipogenic character and meat quality traits associated with pH.

Production of Secondary Metabolites by Some Terverticillate Penicillia on Carbohydrate-Rich and Meat Substrates

Most terverticillate penicillia isolated from dry-cured meat products are toxigenic, but their ability to produce hazardous metabolites on meat-based substrates is not well known. The production of extrolites by selected terverticillate penicillia isolated from dry-cured ham has been studied on carbohydrate-rich media (malt extract agar, Czapek yeast autolysate agar, rice extract agar, and rice), meat extract triolein salt agar, and ham slices. Chloroform extracts from the selected strains grown on malt extract agar were toxic for the brine shrimp (Artemia salina) larvae and VERO cells at a concentration of 2 mg/ml, but 0.02 mg/ml produced no toxic effect. Analysis by high-pressure liquid chromatography (HPLC) coupled with photodiode array detection (DAD) or with mass spectrometry (MS) and an atmospheric pressure chemical ionization (APCI) source revealed different biologically active metabolites: cyclopiazonic acid and rugulovasine A from Penicillium commune; verrucosidin, anacine, puberuline, verrucofortine, and viridicatols from Penicillium polonicum; arisugacin and viridicatols from Penicillium echinulatum; and compactin and viridicatols from Penicillium solitum. Most of these metabolites, including the amino acid–derived compounds, were produced in the media containing high levels of carbohydrates. High concentrations of nitrogen compounds in the medium does not imply a greater production of the metabolites studied, not even those derived from the amino acids. However, molds growing on dry-cured ham are able to synthesize limited amounts of some secondary metabolites, a fact not previously reported. The combination of HPLC coupled with DAD and MS-APCI was useful for identification of closely related terverticillate Penicillium species from dry-cured ham. These techniques could be used to characterize the risk associated with the potential production of secondary metabolites in cured meats.

A new validated HPLC-FLD method for detecting ochratoxin A in dry-cured meat and in blue cheese

In the present study, a fast and sensitive method for the quantification of ochratoxin A in two lipidicproteic food matrices has been developed. In particular, the sample preparation procedure has been optimized for dry-cured meat products and blue cheeses and tested for several validation parameters (LOD, LOQ, recovery, repeatability and within-laboratory precision). The procedure has been then applied to several dry-cured meat products and blue cheeses from the market.Ochratoxin A has been occasionally found in dry-cured and smoked ham from the market and the contamination occurred both in the outer and in the inner part of the products. Concerning the blue cheese, the occurrence of ochratoxin A is reported for the first time: OTA was occasionally found at low levels (0.1-3 μg/kg) in commercial samples of Roquefort from France and Gorgonzola from Italy, opening a new issue for risk assessment and quality control.

Molecular characterization and recuperation of bacteriocins produced by lactic acid bacteria isolated from dry cured-meat products

Molecular characterization and recuperation of bacteriocins produced by lactic acid bacteria isolated from dry cured-meat products

Quantification of zinc–porphyrin in dry-cured ham products by spectroscopic methods: Comparison of absorption, fluorescence and X-ray fluorescence spectroscopy

Zinc–protoporphyrin (Zn–pp), which has been identified as the major pigment in certain dry-cured meat products, was extracted with acetone/water (75%) and isolated from the following meat products: Parma ham, Iberian ham and dry-cured ham with added nitrite. The quantification of Zn–pp by electron absorption, fluorescence and X-ray fluorescence (XRF) spectroscopy was compared (concentration range used [Zn–pp] = 0.8–9.7 μM). All three hams were found to contain Zn–pp, and the results show no significant difference among the content of Zn–pp quantified by fluorescence, absorbance and X-ray fluorescence spectroscopy for Parma ham and Iberian ham. All three methods can be used for quantification of Zn–pp in acetone/water extracts of different ham types if the content is higher than 1.0 ppm. For dry-cured ham with added nitrite, XRF was not applicable due to the low content of Zn–pp (<0.1 ppm). In addition, XRF spectroscopy provides further information regarding other trace elements and can therefore be advantageous in this aspect. This study also focused on XRF determination of Fe in the extracts and as no detectable Fe was found in the three types of ham extracts investigated (limit of detection; Fe ⩽ 1.8 ppm), it allows the conclusion that iron containing pigments, e.g., heme, do not contribute to the noticeable red colour observed in some of the extracts.

Determination of ochratoxin A in dry-cured meat products by a HPLC–FLD quantitative method

A fast and sensitive method for the quantification of the mycotoxin ochratoxin A (OTA) in dry-cured meat products has been developed, which does not require a clean-up step, by HPLC with an alkaline mobile phase (pH 9.8). Validation procedures for specificity, trueness, ruggedness, stability, recovery and repeatability were performed. The decision limit (CC α) and the decision capability (CC β) were calculated at 1.10 and 1.23 μg/kg, respectively. The procedure was applied to representative dehydration levels of dry-cured meat samples.

Technologies to shorten the drying period of dry-cured meat products

Dry-cured meat products are well-known for their unique sensory characteristics. However, the traditional process is very time consuming. The process can be shortened especially by accelerating the drying period, which is the most time consuming. This paper deals with some technological, safety and sensorial aspects for producing fermented sausages and dry-cured hams when the process time is shortened. Different techniques, such as temperature increase and thickness reduction, and the effects of some ingredients and additives are discussed. A Quick-Dry-Slice process based on a continuous system that combines both convective and vacuum drying could accelerate the drying of slices after the desired pH is reached in fermented sausages. There are safety concerns when processes are shortened, but possible additional hurdles, such as the introduction of bacteriocin-producing starter cultures and high-pressure treatments at the end of the process, could reduce them. Methods to speed up the development of typical colour, texture and flavour and their limitations are also discussed.

Volatile Profiles of Dry-Cured Meat Products from Three Different Iberian X Duroc Genotypes

Volatile profiles of two Iberian dry-cured products, dry-cured loin and ham, from three different Iberian x Duroc genotypes, was assessed. Three groups of 10 pigs, each (5 males and 5 females) from different genotypes, were studied: GEN1 = male Iberian x female Duroc1; GEN2 = male Duroc1 x female Iberian; and GEN3 = male Duroc2 x female Iberian. The genotype Duroc1 (DU1) corresponded to pigs selected for the production of dry-cured meat products (hams, loins, and shoulders), with a high level of fattening, while the genotype Duroc2 (DU2) corresponded to animals selected for meat production. Genotype slightly affected the volatile profiles of both dry-cured meat products, although dry-cured loin from GEN3 showed higher hexanal content. Dry-cured loin showed a volatile profile very different to that found in dry-cured ham. Volatile compounds of dry-cured meat products were mainly originated by lipid and protein degradation. Most of the volatile detected in both meat products came from lipid oxidation such as acids, aldehydes, ketones, alcohols, and hydrocarbons. In addition, a high proportion of volatile compounds from the Maillard reaction was found. Branched aldehydes and some sulfur and nitrogen compounds have their origin in the amino acids degradation by the Strecker reaction, while branched alcohols and acids come from the lipid oxidation of branched aldehydes. Dry-cured ham showed a higher number and a higher level of compounds with origin in protein and lipid degradation than dry-cured loin, which agrees with the longer ripening of the hams (24 months) with respect to the loins (4 months). In dry-cured loins, apart from these compounds, seasoning mixture provides high amount of volatiles, such as terpenes (from paprika and oregano) and sulfur compounds (from garlic), which have great importance in the overall aroma of this product.

Effect of Iberian × Duroc genotype on dry-cured loin quality

Dry-cured loins from three different pig genotypes were studied: GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype of pigs Duroc1 was selected for the manufacture of dry-cured meat products, while the genotype Duroc2 was selected for meat production. The chemical composition of the dry-cured loins was significantly different, especially the intramuscular fat (IMF) content which was highest in GEN2. Dry-cured loins from GEN3 showed lower CIE a ∗ and chroma values. IMF from GEN2 was more saturated whereas GEN3 had higher percentages of PUFA and MUFA. Loins from GEN3 had higher TBA-RS values ( p > 0.05) and hexanal contents. Loins from GEN3 had higher Warner–Bratzler shear force ( p > 0.05) and instrumental hardness than those from GEN2, being intermediate in GEN1. Panellists considered that loins from GEN2 were more marbled, more odorous, juicier, sweeter and less salty than loins from GEN3. Therefore, loins from GEN2 had the best quality, followed by GEN1, while GEN3 had the worst quality.

Carcass composition and meat quality of three different Iberian × Duroc genotype pigs

Carcass composition and meat quality of Longissimus dorsi (LD) and Biceps femoris (BF) muscles from three different Iberian × Duroc genotype pigs were studied: GEN1: ♂ Iberian × ♀ Duroc1; GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. Duroc1 (DU1) were selected for the manufacture of dry-cured meat products while Duroc2 (DU2) were pigs selected for meat production, with high percentages of meat cuts and low carcass fat. Genotype had a significant effect on the differences found while sex had not. GEN2 showed the highest weights at days 180 and 238 of weaning and the highest slaughter weights (day 316) followed by GEN3, while the lowest weights were found in GEN1. GEN3 had well conformed carcasses in comparison with GEN1 and GEN2, since GEN3 showed the highest percentages of ham and loin and the highest weight of loin as well as the lowest back and ham fat thickness. However, the use of DU2 pigs in the cross with Iberian had negative effects on meat quality, as GEN3 gave the worst meat quality in both muscles, postmortem pH, cook and drip loss, and colour and the lowest percentages of intramuscular fat (IMF). In subcutaneous fat (SCF), GEN3 had higher percentages of polyunsaturated fatty acids (PUFA) than GEN2, while GEN2 had higher saturated fatty acids (SFA) levels. In LD, IMF from GEN3 showed the highest percentage of MUFA and PUFA; while the fatty acid profile of GEN2 was more saturated. BF muscle showed similar trends, but not significantly so. On the other hand, few differences were found between reciprocal crosses (GEN1 vs. GEN2). GEN2 showed higher IMF in LD than GEN1, agreeing with their carcass weight. As a result, GEN1 had a fatty acid profile of IMF in the LD that was more unsaturated.

Phospholipid oxidation, non-enzymatic browning development and volatile compounds generation in model systems containing liposomes from porcine Longissimus dorsi and selected amino acids

Lipid oxidation, non-enzymatic browning development and volatile compounds generation were studied in sterile meat-model systems containing selected amino acids and/or liposomes during 35 days at 25 °C under pro-oxidative conditions, in order to simulate the ripening conditions of dry-cured meat products. Liposomes were prepared with polar lipids (PL) from Longissimus dorsi muscle of outdoors pigs fed on grass and acorns (M) or indoors ones fed on concentrates (C). Thiobarbituric acid reactive substances (TBA-RS) in systems containing both amino acids and liposomes were higher than in those containing only liposomes. The higher susceptibility to lipid oxidation of liposomes from C animal was reflected in higher TBA-RS throughout the experiment. All model systems containing liposomes and/or amino acids showed non-enzymatic browning development, as measured by the yellowness index. Major volatile compounds were fatty acid oxidation products. Strecker-derived volatile compounds were predominantly detected in model systems containing both amino acids and liposomes. The chromatographic areas of Strecker-derived volatiles increased over time whereas those of lipid-derived volatiles decreased. The occurrence of lipid oxidation, non-enzymatic browning and Strecker-type degradation of amino acids were shown in sterile meat-model systems at low temperatures.

Genetic characterization and expression of the novel fungal protease, EPg222 active in dry-cured meat products

EPg222 protease is a novel extracellular enzyme produced by Penicillium chrysogenum (Pg222) isolated from dry-cured hams that has the potential for use over a broad range of applications in industries that produce dry-cured meat products. The gene encoding EPg222 protease has been identified. Peptide sequences of EPg222 were obtained by de novo sequencing of tryptic peptides using mass spectrometry. The corresponding gene was amplified by PCR using degenerated primers based on a combination of conserved serine protease-encoding sequences and reverse translation of the peptide sequences. EPg222 is encoded as a gene of 1,361 bp interrupted by two introns. The deduced amino acid sequence indicated that the enzyme is synthesized as a preproenzyme with a putative signal sequence of 19 amino acids (aa), a prosequence of 96 aa and a mature protein of 283 aa. A cDNA encoding EPg222 has been cloned and expressed as a functionally active enzyme in Pichia pastoris. The recombinant enzyme exhibits similar activities to the native enzyme against a wide range of protein substrates including muscle myofibrillar protein. The mature sequence contains conserved aa residues characteristic of those forming the catalytic triad of serine proteases (Asp42, His76 and Ser228) but notably the food enzyme exhibits specific aa substitutions in the immunoglobulin-E recognition regions that have been identified in protein homologues that are allergenic.

Evaluation of ACE inhibitory activity of dipeptides generated by the action of porcine muscle dipeptidyl peptidases

Dipeptidyl peptidases (DPP) constitute a group of proteolytic enzymes able to release a good number of dipeptides from the N-terminus of both synthetic substrates and natural polypeptides. Specific sequences generated by the action of DPP purified from porcine skeletal muscle have been assayed to evaluate their capacity to inhibit the activity of angiotensin-I converting enzyme (ACE; EC 3.4.15.1). A fluorimetric assay based on the hydrolysis of the internally quenched fluorescent substrate o-aminobenzoylglycyl- p-nitrophenylalanylproline by the action of ACE was used for this purpose. The generated fluorescence of the product (the o-aminobenzoylglycine group) was continuously monitored in a microtiter-plate multiscan fluorometer. Among the assayed dipeptides, Arg-Pro showed the strongest ACE inhibitory activity, being able to suppress more than 60% of initial enzyme activity at a concentration of 25 μM. Dipeptides Lys-Ala, Gly-Pro and Ala-Ala also demonstrated to be effective ACE inhibitors, although at a lower degree. Dipeptides Ala-Arg and Gly-Arg caused a more moderate inhibition of ACE activity, and even lower was the inhibition exerted by Arg-Arg. From the data obtained, it is suggested that the proteolytic action of DPP along the ripening period of dry-cured meat products could contribute to the generation of antihypertensive peptides.

Headspace concentration of selected dry-cured aroma compounds in model systems as affected by curing agents

The effect of curing agents (sodium chloride, nitrate, nitrite, glucose, and ascorbic acid) on the headspace concentration of six volatile compounds (2-methyl-butanal, 3-methyl-butanal, 2-pentanone, hexanal, methional, and octanal) has been studied. These volatile compounds were selected based on their presence and contribution to the flavour of typical Spanish dry-cured meat products. The release of volatile compounds to the headspace has been studied by using solid-phase microextraction (SPME) and gas chromatography analysis. The main effect was produced by sodium chloride, because it produced a salting-out effect on all the volatile compounds studied. Furthermore, the presence of nitrite, nitrate, and ascorbic acid in the solution also produced an increase in the headspace concentration of the volatile compounds while glucose decreased the headspace concentration of octanal and hexanal. The changes in the relative proportions of volatile compounds due to the effect of curing agents should be taken into account as they may change the flavour perception of dry-cured meat products.

Sensitivity of three pathogenic bacteria to Turkish cemen paste and its ingredients

Pastirma is a dry cured meat product which is pasted with cemen. This paste is prepared from ground fenugreek, garlic and red hot pepper (RHPP). In this study, the cemen mix/paste and all its ingredients were tested for their inhibitory effects on Escherichia coli, Staphylococcus aureus and Yersinia enterocolitica. All samples had a varying inhibitory effect against all the bacteria tested during 4 days of storage. Complete cemen paste showed the strongest inhibitory effect on the three pathogens compared to ingredients alone. Fenugreek and RHPP had a bacteriostatic effect while the cemen paste and garlic had a bactericidal effect. S. aureus was the most sensitive bacterium while Y. enterocolitica was the most resistant. The results of this study confirmed the protective effect of cemen paste and garlic in food preservation especially against E. coli, S. aureus and Y. enterocolitica proving safety for public health. Hence it might be concluded that cemen paste is the first hurdle to prevent bacterial contamination, and a low pH (∼4.83) value would also add an additional barrier to secure safety of the product. Finally, it can be suggested that similar studies should be conducted on actual meat systems to confirm these findings.

Contribution of a selected fungal population to the volatile compounds on dry-cured ham

Dry-cured ham is obtained after several months of ripening. Different fungi strive on the surface, including toxigenic molds. Proteolysis and lipolysis by the endogenous and microbial enzymes seem to play a decisive role in the generation of flavor precursors in dry-cured meat products. In addition, fungi show a positive impact on the volatile compounds of ripened pork loins. However, the contribution of the fungal population to flavor formation in dry-cured ham remains unclear. One selected strain each of Penicillium chrysogenum and Debaryomyces hansenii was inoculated as starter cultures on dry-cured ham. Volatile compounds extracted by solid phase micro-extraction technique were analyzed by gas chromatography/mass spectrometry. A trained panel evaluated flavor and texture of fully ripened hams. The wild fungal population on non-inoculated control hams correlates with higher levels of short chain aliphatic carboxylic acids and their esters, branched carbonyls, branched alcohols, and some sulfur compounds, particularly at the outer muscle. Conversely, P. chrysogenum and D. hansenii seem to be responsible for higher levels of long chain aliphatic and branched hydrocarbons, furanones, long chain carboxylic acids and their esters. The very limited impact of P. chrysogenum on pyrazines in inoculated hams can be due to the activity of the yeast. Lower levels for some of the more volatile linear carbonyls at the ham surface suggest an anti-oxidant effect by micro-organisms. The differences in volatile compounds did not show a neat impact on flavor in the sensorial analysis. Nonetheless, inoculated hams got a better overall acceptability, which has to be attributed to their improved texture. The lower toughness of inoculated hams is a direct consequence of an early settling of a highly proteolytic mold. Thus, the use of selected fungi as starter cultures may be useful to obtain high-quality and safe dry-cured ham.

Zn-porphyrin formation in cured meat products: Effect of added salt and nitrite

Zn-porphyrin (Zn-pp) was quantified by fluorescence spectroscopy in the cured and dry cured meat products: Parma ham, Iberian ham, dry-cured ham with added nitrite, cooked ham with added nitrite, raw ham meat, raw bacon and Karree-Speck. The highest amount of Zn-pp was found in dry-cured Parma ham and Iberian ham, while the use of nitrite as curing agent was found to inhibit completely the formation of Zn-pp in meat products. A positive correlation between both Zn content and Fe content and the logarithmic transformed Zn-pp content (measured as fluorescence intensity I fl) was found for the different cured and dry cured meat products, with correlation coefficients of 0.79 ( p < 0.001) and 0.71 ( p < 0.01), respectively. Log I fl correlates best with the Zn content, indicating that the formation of Zn-pp is proportional to the Zn content. A model system with vacuum packed pork in brine with different added levels of sodium chloride with or without nitrite and Zn acetate was investigated in order to further elucidate the mechanism of Zn-pp formation. Zn-pp increased with time (up to 42 days investigated) in non-cured meat and for meat cured solely with NaCl lower than 9%. Addition of nitrite or Zn(II) in the curing brine was found to inhibit formation of Zn-pp confirming the observations from the various cured meat products. It is suggested that a chloride anion assisted dissociation of iron from myoglobin could be rate-determining for Zn-pp formation in meat products.