Evaluation of the antioxidant effect of a phytocomplex addition in clean label pork salami enriched in n-3 PUFA.

Control and n-3 PUFA enriched raw material was used to manufacture clean label and conventional salami; the former were added with a phytocomplex having iron chelating, DPPH, and FRAP activity, obtained from olive vegetation water, oregano, green tea and blueberry leaves, and with acerola powder. Salami were dried at 3 ± 1 °C until an established decrease in the combined pH and aw values, while only the conventional ones underwent a standard process. In the cold dried salami pH changes, aw and weight decrease were delayed; the phytocomplex contributed to lower the pH, and to prevent lipid and protein oxidation, despite the n-3 PUFA enrichment and heme iron release due to nitrite removal. TBARS and protein carbonyls were the highest in the nitrite-added salami undergoing cold and standard drying, respectively. The oxidation marker MDA tended to increase in the simulated digests of salami n-3 PUFA enriched or subjected to cold drying.

Application of a non-invasive tool and identification of genetic markers in swine to enhance ham quality: a preliminary study.

A genome-wide association study (GWAS) was performed as a preliminary step to identify regions potentially related to ham quality traits. In this research, genomic information was obtained from 238 commercial hybrid pigs utilising the GeneSeek® Genomic Profiler genome-wide porcine genotyping array. Carcasses were tested for hot weight, the thickness of backfat and loin, and lean meat percentage. The corresponding fresh hams were assayed for weight and ultimate pH; the activities of Cathepsin B and Ferrochelatase of Semimembranosus muscle were determined through fluorimetric methods. The lean meat percentage of fresh ham (LMPH), salt absorbed after first (SALT1) and overall salting stages (SALT) were estimated online by the Ham Inspector™ apparatus. Hams were processed in compliance with the procedures established for Protected Designation of Origin Parma ham, and ham weight losses were measured at the main processing stages. Hot carcass weights showed a significant negative correlation with their lean meat percentage and LMPH, while LMPH was correlated positively with carcass lean meat, SALT1, SALT, and weight losses. The GWAS detected genome-wide association for 12 single nucleotide polymorphisms with Ferrochelatase activity. The results obtained in this preliminary study were achieved by combining innovative and non-destructive technologies for screening hams under processing, measures of enzymatic muscle properties relevant to dry-cured ham quality, and genomic information obtained through a GWAS. Additional studies carried out in a larger number of pigs have been planned to investigate the effect of gene variants of Ferrochelatase activity in the dry-cured ham's quality with main reference to colour development and to confirm the GWAS results obtained in this study.

Revision of the cold processing phases to obtain a targeted salt reduction in typical Italian dry-cured ham.

The objective of the study was to reduce the salt content of typical Italian dry-cured ham by at least 25%, to meet the "reduced salt" claim. Salt reduction needs process adjustments to maintain product safety and quality in the absence of nitrites. A way was to reduce the salt input and to shorten the salting period compared to the conventional process. The cold drying period of reduced salt (RS) hams was extended, to decrease aw below 0.97 in inner parts and obtain the same safety conditions of control hams (CS). In RS dry-cured hams the salt reduction was accomplished, the generation of biogenic amines was lower than the threshold values generating toxic effects, and color was the same as in the CS ones. However, in RS proteolysis increased, contributing to texture softening. A strengthened salt diffusion from backside rind could contribute to counteract the rise in proteolysis of biceps femoris muscle, depleted of salt during the process of RS hams.

Effect of vaccination against gonadotropin-releasing hormone (GnRH) in heavy male pigs for Italian typical dry-cured ham production.

The aim of this study was to evaluate immunocastration (vaccination against GnRH using Improvac® vaccine), as an alternative to surgical castration in heavy male pigs (average live weight 165 ± 10 kg), used in the production of Italian typical dry-cured ham. A total of 60 Landrace × Large White male pigs were assigned to three groups of 20 units, including one group of surgically castrated (SC), and two of immunocastrated pigs, with two (IC2) or three (IC3) vaccine treatments, respectively. The groups were compared for green ham traits, processing weight losses, chemo-physical, and sensory properties of dry-cured hams. While IC3 were not different (P>0.05) from SC group, IC2 hams were found to differ (P<0.05) both from SC and IC3 groups in ham traits, final weight losses, texture and sensory boar taint in finished hams. Therefore, vaccination with three doses could be taken into account to control boar taint in the manufacturing of typical Italian dry-cured ham.

Effect of age at slaughter on carcass traits and meat quality of Italian heavy pigs.

Barrows and gilts (n = 128) from four breed crosses were used to investigate the effect of age at slaughter on carcass traits, proteolytic enzyme activity, and meat and fat quality. Pigs were blocked by breed cross into four blocks, and within blocks, one pen (eight barrows and eight gilts) was assigned randomly to be slaughtered at either 8 or 10 mo of age. Pigs were fed a corn-barley-soybean meal finisher diet from 104 +/- 2.5 d of age (37.7 +/- 0.33 kg BW) to the appropriate slaughter age. Carcasses from older (10 mo) pigs had lower (P < 0.01) muscularity indexes and lean cut yields than those of younger (8 mo) pigs, but dressing percentage and longissimus muscle area increased (P < 0.01) with age. Older pigs produced a redder (P < 0.01) and darker (P < 0.05) semimembranosus, with lower (P < 0.01) ultimate pH and cathepsin B and B + L activities, as well as higher (P < 0.01) aminopeptidase hydrolyzing activity than younger pigs. Moreover, the longissimus muscle of pigs slaughtered at 10 mo of age had lower (P < 0.01) drip and cooking loss percentages than that from pigs slaughtered at 8 mo of age. Ham subcutaneous fat from 10-mo-old pigs had greater (P < 0.05) percentages of oleic acid and lower (P < 0.01) proportions of moisture, linoleic, and linolenic acids than subcutaneous fat from pigs slaughtered at 8 mo of age. Results from this study indicate that fresh hams from pigs slaughtered at 10 mo of age would be more suitable for the production of high-quality, Italian, dry-cured hams.

Muscle traits for long matured dried meats.

The distinctive flavour of aged pork products is a complex mix of taste, smell and even touch. To meet increasing consumer's preference for ethnic foods or foods addressing linkage with specified geographic origin or complying with traditional manufacturing and breeding guidelines, efforts should be made to encourage selection of processing techniques and raw materials targeting desired end product qualities. Thanks to research carried out with sensory analysis and chemical and physical characterisation of raw and matured pork, as well as breeding and genetics, improved knowledge is now available relating dried meat properties to raw matter or manufacturing. The achievement of the distinctive taste and texture properties of aged products through genetics (animal selection for the enhancement or the removal of some muscle traits), breeding (effect of diet and slaughtering age on pork properties) with reference to current findings about this type of products is discussed.

Relationship between cathepsin B activity and compositional parameters in dry-cured hams of normal and defective texture.

Thirty-eight Italian dry-cured hams were analysed for cathepsin B activity, proximate composition and proteolysis index and results were related to lean tissue texture, as assessed by an expert panel, in order to search for relationships between excessive softness, a major problem in the raw ham industry, and chemical parameters. Softness was found to be related to protein breakdown which, in turn, was linked with higher residual cathepsin B activity and, to a lesser extent, to lower salt content. Results suggest that the use of raw ham of controlled enzyme activity would improve the texture quality of the end product.

Lipolysis in dry-cured ham maturation.

Thirty light Parma hams were tested for muscle lipolytic activity (acid and neutral lipase activity) and free fatty acid (FFA) amounts in M. semimembranosus and biceps femoris, during progressive phases (0, 3, 6, 10 months) of dry-cured ham manufacturing. No correlation was found between the activities of acid and neutral lipases in fresh M. semimembranosus, while during processing the activities were positively related (p<0.1), probably due to effects of muscle composition changes on lipolytic activities. In each processing step tested, acid lipase activities were higher in the M. semimembranosus than in the M. biceps femoris, and FFA amounts varied accordingly, the only exception being for the very dehydrated 10-month old M. semimembranosus, which yielded lower FFA than in the corresponding M. biceps femoris. FFAs in the end product correlated positively with acid and neutral lipase activities of green ham, suggesting that FFA production could be influenced by both raw meat properties and muscle composition during processing.

Analysis of raw meat to predict proteolysis in Parma ham.

Four hundred and thirty-seven pigs (223 purebred Italian Large White, 97 Italian Landrace, and 117 Duroc), were studied to examine the effect of breed on meat quality and assess the possibility of relating proteolysis of dry-cured hams to raw meat quality. The Duroc pigs had intramuscular fat contents and water holding capacities (M. Semimembranosus) significantly higher than those of the Large White and Landrace. The latter had a significantly higher pH(24h) and cathepsin B activities significantly lower than the Duroc breed. The dry-cured hams (M. Biceps femoris) from the three breeds were significantly different in proximate composition, proteolysis and weight loss at the end of ageing. Data for green hams (including salt content) were used to compute a model to fit the proteolysis of the corresponding dry-cured hams. The variables included in the model (R(2)=0.53 and P<0.01) were cathepsin B activity of raw ham, pH(24h), weight loss after the first salting step, and the salt content of the dry-cured ham. The raw hams with the highest cathepsin B activities, the lowest pH(24h), and the highest weight loss after the first salting were those in which greatest proteolysis occured.