A comparison of meat composition, tenderness and the fatty acid profile of three muscles from Holstein-Friesian bulls from production system resulting in final ages of either <16 or 19 months

Context The increased number of male dairy origin calves in Ireland due to the abolition of European Union milk quotas is a potential resource for the beef industry. Rearing these animals as bulls rather than steers is more efficient from a production perspective. Ensuring satisfactory quality of bull beef from dairy origin is essential. Aim To determine the effect of two production systems and three muscle types on physico-chemical characteristics and fatty acid (FA) profile of beef from Holstein-Friesian (HF) bulls. Methods Thirty HF bulls were equally assigned to two production systems, namely, slaughter at under 16 months of age or slaughter at 19 months of age. Longissimus thoracis (LT), Semitendinosus (ST) and Gluteus medius (GM) muscles were excised post-slaughter for determination of pH, colour, Warner–Bratzler (WB) variables, cook loss, chemical composition [intramuscular fat (IMF), moisture, protein, ash], collagen characteristics and FA profile. Results WB variables and cook loss after 14 days postmortem ageing, and insoluble and total collagen contents were higher, while IMF content, redness and saturation at 24 h post-blooming were lower for muscles from the 19-month production system. Muscles from the under 16-month production system had a higher saturated fatty acid (SFA) proportion and n-6:n-3 polyunsaturated fatty acid (PUFA) ratio, while muscle from the 19-month production system had a higher PUFA proportion, n-3 PUFA proportion and PUFA:SFA ratio. The GM muscle had the lowest L* value, followed by LT and ST. Yellowness, saturation and hue angle were greater in ST. LT had lower WB variables, cook loss, moisture, and a higher IMF content than ST and GM. The PUFA proportion and PUFA:SFA ratio were highest in ST, followed by GM and LT. IMF, total FA, SFA and monounsaturated fatty acid (MUFA) concentrations were higher in LT from the under 16-month production system bulls (the interaction). Conclusions Beef from the under 16-month production system compared with beef from the 19-month production system, and LT compared with ST and GM muscles had better quality characteristics. Implications Dairy bulls can produce beef of acceptable quality. The findings will guide selection of the combination of production system and muscle type most appropriate to specific market requirements.

Discrimination of Meat Produced by Bos taurus and Bos indicus Finished under an Intensive or Extensive System

Simple Summary

This research was carried out to investigate the usefulness and reliability of meat quality traits such as physicochemical properties and fatty acid profiles to discriminate between meat produced by taurine and zebu cattle, finished on pasture or grain. This approach is of utmost importance to assess the authenticity of meat products, particularly when beef is certified based on criteria such as breed and finishing system. Our results using discriminant analyses indicate that meats originating from pasture- or grain-finishing can be discriminated with high reliability, essentially on the basis of their fatty acid profile. The global distinction of meat from the two genetic groups is somewhat more difficult to achieve reliably. Still, prior knowledge of the finishing system used to produce meat from a given genetic group enhances the trustworthiness of the assignment procedure, allowing the reliable allocation of meat samples originating from Bos indicus and Bos taurus finished on pasture or grain, with fatty acid profiles being better discriminating factors than physicochemical properties. These results can be adopted as tools to be used in meat certification programs.

Abstract

Meat obtained under commercial conditions shows considerable variability, mostly due to genetic background and production system. In this study, meat physicochemical properties and fatty acid profiles were analysed to investigate the feasibility of using them as tools to discriminate between meats produced by different genetic groups and finishing systems. Samples of the Longissimus thoracis were collected from 160 commercial bulls of the B. taurus (n = 75) and B. indicus (n = 85) groups, finished either on pasture (n = 46) or with grain supplementation (n = 114) and analysed by standard procedures. Data were analysed by discriminant analysis using a stepwise procedure, to select the meat characteristics that better contribute to discriminate the various groups. Our results indicate that fatty acid profiles of meat had better discriminating ability than physicochemical properties, especially to identify meat from animals finished on grain or pasture. The overall discrimination of meat from different genetic groups was achieved with a slightly lower reliability. Nonetheless, our results show that reliability of allocation to genetic group can be improved if prior information on finishing system is considered. These results are of high importance because they can be incorporated as tools to assess the authenticity of beef, particularly in meat certification programs.

Wójciak K. Peptides from Different Carcass Elements of Organic and Conventional Pork-Potential Source of Antioxidant Activity

The growing consumer interest in organic foods, as well as, in many cases, the inconclusiveness of the research comparing organic and conventional foods, indicates a need to study this issue further. The aim of the study was to compare the effects of meat origin (conventional vs. organic) and selected elements of the pork carcass (ham, loin, and shoulder) on the meat proteome and the antioxidant potential of its peptides. The peptidomic approach was used, while the ability of antioxidants to scavenge 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS), to chelate Fe(II) ions, and to reduce Fe(III) was determined. Most peptides were derived from myofibrillary proteins. The meat origin and the element of the pork carcass did not have a significant effect on the proteome. On the other hand, the pork origin and the carcass element significantly affected the iron ion-chelating capacity (Fe(II)) and the reducing power of peptides. In particular, pork ham from conventional rearing systems had the best antioxidant properties in relation to potential antioxidant peptides. This could be a factor for human health, as well as for stabilized meat products (e.g., toward lipid oxidation).