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9 Pág. Departamento de Tecnología de Alimentos​​, Lipid oxidation and proteolysis are essential processes in Serrano dry-cured ham quality. The influence of high pressure processing (HPP) at 600 MPa for 6 min on lipid oxidation, aminopeptidase (AP) activities and free amino acids (FAA) in ripened Serrano hams of different chemical composition after 5 months at 4 °C were studied. HPP increased lipid peroxidation indexes. Composition influenced both indexes, with higher levels in hams of medium or high intramuscular fat (IMF) content and in hams of low or medium salt content or salt-in-lean ratio. HPP lowered AP activities by more than 50%. Composition also affected AP activities, with lower levels in hams of low aw, high IMF content, low salt content or low salt-in-lean ratio. At the end of refrigerated storage, HPP only affected Arg and Tyr levels. Many of the individual FAA reached higher levels in hams of low aw, medium or high IMF content, low or medium salt content, or low or medium salt-in-lean ratio., The authors wish to thank the Spanish Ministry of Science and Innovation, which supported the experimental work through project RTA2010-00029-C04-04; E. Fulladosa, P. Gou and J. Arnau (IRTA, Monells, Spain) for the selection and processing of hams; A. del Olmo for support in the lipid oxidation measurements; and INIA for funding the Ph.D. grant of N. Martínez-Onandi.

The effect of high pressure processing (HPP) at 600 MPa and refrigerated storage for 5 months on the volatile fraction of 30 Iberian dry-cured hams of different compositional characteristics was investigated. Compositional characteristics significantly influenced 11 compounds (3 alcohols, 3 carboxylic acids, 2 alkanes, 2 benzene compounds and 1 aldehyde) out of the 116 compounds identified in the volatile fraction of Iberian ham. HPP treatment had a significant effect on 34 volatile compounds, with higher levels of 11 compounds and lower levels of 23 compounds in HPP-treated samples than in control samples. Refrigerated storage for 5 months significantly influenced the levels of 75 compounds, 25 of which appeared or increased while 50 disappeared or decreased. During that period, the total abundance of volatile compounds decreased by 5.1% in control ham and 1.3% in HPP-treated ham. Iberian ham commercial shelf life should be limited to maintain its sensory characteristics. Industrial relevance HPP treatment and refrigerated storage of dry-cured ham are advantageous industrial and commercial procedures. In the particular case of Iberian ham, both HPP and refrigerated storage brought about a decrease in the total levels of volatile compounds. Therefore, adequate HPP treatment conditions and commercial shelf life should be cautiously set in order to safeguard the unique odor and aroma characteristics of Iberian ham.

Spain is the biggest olive oil producer in the world what means that this area is especially affected by olive mill waste pollution. The main system used for extracting olive oil is the continuous two-phase centrifugation system, which generates olive wet cake waste. This wastage has disposal problems due to its phytotoxicity and high moisture content, so strategies for its use and revalorization are needed. One of these strategies is the extraction of bioactive compounds, as is the case of polyphenols present in the waste, which could be used as natural antioxidants in food. This study evaluated the effect of adding an olive waste extract (100, 200 or 400 mg gallic acid equivalents/kg muscle), as a possible natural polyphenol-rich antioxidant on the stability of lamb meat patties enriched with omega-3 fatty acids, and stored in high-oxygen modified atmosphere packs for up to 9 days at 4 °C. Addition of the extract delayed meat discolouration, lipid oxidation (p ≤ 0.001) and protein carbonylation (p ≤ 0.001), and increased loss of thiol groups (p ≤ 0.05) relative to controls. Fish odour (p ≤ 0.01) and flavour (p ≤ 0.05) were lower and odd odour and flavour (p ≤ 0.001) higher in patties with added the extract compared to controls, but the overall liking score was not affected. The addition of the extract resulted in acceptable lamb meat patties (in terms of oxidation) after 6 days of storage, while patties without extract did not. The results pointed out the potential for using olive waste extracts as natural antioxidants in meat products. With this strategy, the olive oil industry would encourage to follow an eco-friendlier olive oil production chain obtaining marketable products from the wastes generated. At the same time, the shelf-life (in terms of oxidation process) of the lamb patties would be increased reducing food wastes at the point-of-sale and at consumer level, which is especially important in a high perishable food such as minced meat products, and reducing the environmental impact that food waste causes along the food supply chain. © 2016 Elsevier Ltd

The volatile fraction of 30 Iberian dry-cured hams of different physicochemical characteristics and the effect of high pressure processing (HPP) at 600 MPa on volatile compounds were investigated. According to the analysis of variance carried out on the levels of 122 volatile compounds, intramuscular fat content influenced the levels of 8 benzene compounds, 5 carboxylic acids, 2 ketones, 2 furanones, 1 alcohol, 1 aldehyde and 1 sulfur compound, salt concentration influenced the levels of 1 aldehyde and 1 ketone, salt-in-lean ratio had no effect on volatile compounds, and water activity influenced the levels of 3 sulfur compounds, 1 alcohol and 1 aldehyde. HPP-treated samples of Iberian ham had higher levels of 4 compounds and lower levels of 31 compounds than untreated samples. A higher influence of HPP treatment on volatile compounds than physicochemical characteristics was observed for Iberian ham. Therefore, HPP treatment conditions should be optimized in order to diminish its possible effect on Iberian ham odor and aroma characteristics. © 2017 Elsevier Ltd

The microbiota of Serrano dry-cured ham of different chemical composition, subjected or not to high-pressure processing (HPP), was investigated using culture-dependent and culture-independent methods. Microbial counts were submitted to analysis of variance with physicochemical parameters (a w , NaCl concentration, salt-in-lean ratio and intramuscular fat content) or HPP as main effects. In untreated hams, physicochemical parameters significantly affected counts of aerobic mesophiles, psychrotrophs, and moulds and yeasts. NaCl concentration and fat content influenced the levels of four and three of the five studied microbial groups, respectively, whereas no influence of a w was stated. The HPP treatment had a significant effect on counts of all investigated microbial groups. Culture-independent methods showed the presence of bacteria such as Staphylococcus equorum , Staphylococcus succinus , Bacillus subtilis and Cellulosimicrobium sp., moulds like Penicillium commune , Aspergillus fumigatus , Sclerotinia sclerotiorum , Eurotium athecium and Moniliella mellis , and yeasts like Debaryomyces hansenii and Candida glucosophila . Absence of B . subtilis bands and weaker bands of E . athecium were recorded for HPP-treated hams. The higher microbial levels found in lean ham might result in a quicker deterioration. HPP treatment confirmed its suitability as a procedure to control spoilage microorganisms. DGGE did not seem to be sensitive enough to highlight changes caused by HPP treatment in the microbiota of ham, but contributed to the detection of microbial species not previously found in ham.

One hundred and three volatile compounds were detected by solid-phase microextraction followed by gas chromatography–mass spectrometry in 30 ripened Serrano dry-cured hams, submitted or not to high pressure processing (HPP) and afterwards held for 5 months at 4 °C. The effect of ham physicochemical parameters and HPP (600 MPa for 6 min) on volatile compounds was assessed. Physicochemical parameters primarily affected the levels of acids, alcohols, alkanes, esters, benzene compounds, sulfur compounds and some miscellaneous compounds. Intramuscular fat content was the physicochemical parameter with the most pronounced effect on the volatile fraction of untreated Serrano ham after refrigerated storage, influencing the levels of 38 volatile compounds while aw, salt content and salt-in-lean ratio respectively influenced the levels of 4, 4 and 5 volatile compounds. HPP treatment affected 21 volatile compounds, resulting in higher levels of alkanes and ketones and lower levels of esters and secondary alcohols, what might affect Serrano ham odor and aroma after 5 months of refrigerated storage. © 2016 Elsevier Ltd

High-pressure processing (HPP) is a non-thermal mild technology of particular interest to the meat sector since it guarantees microbiological safety and extends product shelf-life without modifying nutritional and sensory characteristics. This chapter reviews published information on the effect of HPP on the volatiles of pork meat products. Pressurization does not markedly modify the volatile profile of pork meat products immediately after treatment, but the volatile profiles of treated and untreated products during storage usually differ. The effect of HPP greatly depends on the treatment conditions, particularly pressure level, and on the type of meat product. Sampling techniques for the analysis of volatile compounds in meat products are also discussed.

The aim of this work was to improve the fatty acid profile of meat from light lamb, frequently reared in Spain and in other Mediterranean countries. A total of 44 light lambs fed different n-3 polyunsaturated fatty acids sources were studied: control (C) (palm oil), extruded linseed (L), extruded linseed mixed with microalgae (LM) and fish oil (FO). The productive performance from 14.7 to 26.2 kg of live weights and meat quality characteristics during refrigerated storage were assessed. Lambs fed FO showed lower feed intake (p p p p p p p p p

Thirty lambs were assigned to the following treatments control diet (C) rich in omega-3 fatty acids; C plus 900ppm red wine extract (RWE), or C plus 300ppm vitamin E (VE). Oxidative stability and sensory properties of chops stored in MAP (70% O2/30% CO2) during 12days were evaluated. Chops from the VE group showed lower lipid oxidation (p

The effect of dietary supplementation with either vitamin E (300ppm) or a red wine extract rich in polyphenols (900ppm) in an omega-3 enriched concentrate on the volatile fraction of lamb meat was assessed. The effect of refrigerated storage (0 and 6days) under high-oxygen atmospheres (70% O 2/30% CO 2) was also studied. Extraction and analysis of the volatile compounds was carried out by headspace solid-phase microextraction (HS-SPME) and GC-MS, respectively. Vitamin E supplementation led to lower levels of lipo-oxidation compounds, such as 2-heptanone and 1-penten-3-ol. The red wine extract was less efficient against lipid oxidation than vitamin E but more efficient than the control (no added antioxidants). The levels of numerous lipid-derived compounds were found to be lower after 6days of storage which could be due to further interactions with protein-related compounds. © 2012 Elsevier Ltd.

Meat is considered to be a good source of protein with high biological value as well as of micronutrients such as minerals (iron, zinc, selenium, …) and vitamins (B6, B12, A, D, …) with a high degree of bioavailability. These micronutrients are either not present in plant-derived food or have poor bioavailability. Consequently, consuming moderate amounts of lean meat as part of a balanced diet makes a valuable contribution to the intake of essential nutrients [1]. However, some constituents of meat, especially in red meat and meat products, have been proposed to be responsible for the development of cardiovascular disease and colon cancer. These elements include the fat content and the fatty acid composition. Meat and meat products are generally classified as “high-fat products”, although the various products available differ markedly in terms of their total fat content. Meat is generally considered to have a fat content in the range 1–20 %, depending on the retail cut and the amount of fat trimmed. Both the fat content and fatty acid composition of meat are influenced by factors such as species, breed, sex, age/weight and diet [2]. Figure 5.1 shows the fat content and fatty acid composition of some meats and meat products obtained from different species. The fat content is usually higher in processed meat products (5–40 %), where large amounts of fatty tissue are used.

Two extraction techniques, dynamic headspace extraction (DHE) and solid-phase microextraction (SPME), were compared to assess the effect of high-pressure treatment (400 MPa, 10 min, 12 °C) on the volatile compounds of low-acid fermented sausage "espetec" and sliced cooked pork shoulder stored at 4 °C. DHE was more efficient at extracting low-boiling compounds such as ethanal, 2,3-butanedione and alcohols, while SPME extracted more efficiently a higher number of chemical families, especially fatty acids. The effect of pressurisation on the volatile fraction of "espetec" was better categorized by DHE, whereas SPME was more appropriate for cooked pork shoulder. The volatile fraction of "espetec" changed slightly after pressurisation, mainly showing a decrease in the levels of lipid-derived compounds, like linear alkanes, aldehydes, or 1-alcohols in pressurised samples. The volatile profile of cooked pork shoulder underwent substantial changes during refrigerated storage, mainly due to microbial metabolism, most of these changes being limited by HPP. © 2011 Elsevier Ltd. All rights reserved.

The effect of high-pressure processing (pressure levels of 400, 500 and 600. MPa, and exposure times of 5 and 10. min) on the volatile profile of vacuum-packaged sliced cooked pork shoulder held for 28. days at 4 °C was assessed. The volatile fraction of pressurized samples scarcely changed immediately after treatment and remained stable for 14. days, regardless the pressure and time of exposure. After 21. days of storage, significant differences were observed in the profile of volatile compounds in pressurized samples as compared with control samples, these differences being treatment dependent. At the end of the storage period, control and 400. MPa samples showed higher levels of acetic and fatty acids, ethanol and ethyl esters, whereas 500 and 600. MPa samples contained higher levels of ethanal, branched-chain aldehydes, diacetyl, acetoin, and 2,3-butanediol among other compounds. These results suggest that the high-pressure treatment had a discriminant effect on the microbiota of cooked pork shoulder, which led to the accumulation of different volatile compounds during the refrigerated storage of control and pressurized samples. © 2010 Elsevier Ltd.

The effect on the volatile profile of cooked beef meat, previously subjected to high pressure (400. MPa, 10. min at 12 °C) followed by a 3-d refrigerated storage, was investigated by comparing two extraction techniques i.e. dynamic headspace and solid-phase microextraction. Dynamic headspace was more efficient in extracting 2,3-butanedione and secondary alcohols. Solid-phase microextraction, being more efficient in extracting substances such as 1-alcanols, ethyl esters and acids, permitted to better categorize the effects caused in the volatile fraction by refrigerated storage and high pressure processing. The volatile fraction of cooked control beef meat contained high amounts of diketones and low amounts of methyl ketones, secondary alcohols, aldehydes and fatty acids. While diketones nearly disappeared after the 3-d refrigerated storage, the other compounds together with ethanol and ethyl esters increased significantly. Pressurized beef samples underwent fewer changes than non-pressurized samples during refrigerated storage, leading to a volatile profile closer to that of control beef. © 2010 Elsevier Ltd.

Hispánico cheese is manufactured in Spain from a mixture of cow and ewe milk. Production of ewe milk varies throughout the year, with a peak in spring and a valley in summer and autumn. To overcome this seasonal shortage, curd from spring ewe milk may be frozen and used for cheese manufacture some months later. In the present work, ewe milk curds pressed for 15, 60, or 120. min were held at -24°C for 4 mo, thawed, cut to 1-mm pieces, and mixed with fresh cow milk curd for the manufacture of experimental Hispánico cheeses. Control cheese was made from a mixture of pasteurized cow and ewe milk in the same (8020) proportion. Cheeses, made in duplicate experiments, were analyzed throughout a 60-d ripening period. No significant differences between cheeses were found for lactic acid bacteria counts, dry matter content, hydrophilic peptides, 47 out of 68. vol.tile compounds, texture, and flavor characteristics. On the other hand, differences of minor practical significance between experimental and control cheeses, unrelated to the use of frozen ewe milk curd or the pressing time of ewe milk curd, were found for pH value, aminopeptidase activity, proteolysis, hydrophobic peptides, free amino acids, free fatty acids, and the remaining 21. vol.tile compounds. It may be concluded that the use of frozen ewe milk curd in the manufacture of Hispánico cheese does not alter its main characteristics. © 2010 American Dairy Science Association.

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of Spanish dry-fermented sausage 'salchichón', packaged with or without aluminium foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressure-treated samples showed significantly higher levels of alcohols, aldehydes and alkanes and lower levels of two methylketones as compared with control samples. An intense migration was observed of compounds from the plastic material into the product, mainly linear and branched-chain alkanes, alkenes and benzene compounds. Most of these migrating compounds were significantly more abundant in pressurized samples than in untreated samples. © 2009 Elsevier Ltd. All rights reserved.

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of Spanish dry-cured Serrano ham, packaged with or without aluminum foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressure treatment only had a slight effect on the volatile fraction of Serrano ham. Most compounds affected by pressurization, such as alkanes (C9-C12), 2-undecene, 2-nonanone, 1-octen-3-one, 1-heptanol, 2-hexanol, 2-heptanol, ethyl pentanoate, benzaldehyde and styrene, presumably originated from the metabolism of moulds. A significant effect of pressurization on the migration of compounds from the plastic material was found. Linear and branched chain alkanes, alkenes as well as benzene compounds, were generally less abundant in pressurized samples than in untreated samples. A scalping effect was also observed for compounds such as butanal, pentanal, ethyl esters and pyrazines. © 2009 Elsevier Ltd. All rights reserved.

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of minced beef and chicken breast, packaged with or without aluminum foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressurization produced significant changes in the levels of some volatile compounds presumably coming from microbial activity. Some alcohols and aldehydes decreased, while other compounds, such as 2,3-butanedione and 2-butanone, were more abundant in high pressure processed meats. A significant migration of compounds from the plastic material was observed, mainly branched-chain alkanes and benzene compounds. Two functions built by the principal component analysis explained a high percentage of the variance and could be used to separate the samples into four distinct groups, according to high pressure treatment and packaging material. © 2008.