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The ability of brown seaweed extracts, Ascophyllum nodosum, Laminaria hyperborea, Pelvetia canaliculata, Fucus vesiculosus and Fucus serratus to protect against tert-butyl hydroperoxide (tert-BOOH) induced stress in Caco-2 cells was investigated. Oxidative stress was determined by measuring alteration in the enzymatic activity of catalase (CAT) and superoxide dismutases (SOD) and cellular levels of glutathione (GSH). L. hyperborea, P. canaliculata and F. serratus significantly protected against tert-BOOH induced SOD reduction but did not protect against the reduction in CAT activity or the increased cellular levels of GSH. The ability of F. serratus and F. vesiculosus to protect against H(2)O(2) and tert-BOOH induced DNA damage was also assessed. The DNA protective effects of the two seaweed extracts was compared to those of three metal chelators; deferoxamine mesylate (DFO), 1,10-phenanthroline (o-phen) and 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis (BAPTA-AM). F. serratus and F. vesiculosus significantly protected (P

The antioxidant potential of methanolic extracts of brown seaweeds was assessed by Total Phenol Content, Ferric Reducing Antioxidant Power (FRAP), β-carotene bleaching and the DPPH scavenging assays. Ascophyllum nodosum, Pelvetia canaliculata, and Fucus serratus contained the highest phenol concentrations while Fucus vesiculosus and F. serratus exhibited the highest FRAP activities. F. vesiculosus and A. nodosum were the most effective extracts at scavenging DPPH radicals and preventing β-carotene bleaching. The antioxidant activity of the seaweed extracts was also evaluated in Caco-2 cells. All extracts significantly (P

The effectiveness of increasing CLA in pork products through animal dietary supplementation or direct addition in the product formulation has been studied, and the effect of grilling on dry matter and fat contents and fatty acid composition has been analysed. Sausages made with meat and back fat from pigs with CLA dietary supplementation had the highest saturated fatty acid content. Sausages from dietary supplementation and direct addition had CLA levels between 6% and 7% of total fatty acids. Moisture and fat contents decreased and increased respectively after cooking for the three sausage types (control, dietary supplementation, direct addition). Grilling had little effect on fatty acid levels, especially for sausages with direct addition in the product formulation. In general, saturated fatty acids increased and poly-unsaturated fatty acids decreased due to the increase of C16:0 and to the decrease of C18:2 n 6c and C18:3 n 3 fatty acids. Added CLA, both from animal dietary supplementation or direct addition, remained at similar levels in cooked sausages to those found in raw sausages.

Approaches for improving the profile of functional unsaturated fatty acids in pork products include dietary supplementation of pigs with functional oils. Little information is available to indicate the benefit of this approach in a processed and cooked pork product such as breakfast sausages. Therefore, the aim of the present study is to examine the fatty acid profile and oxidation level in cooked pork sausages, produced following dietary supplementation with CLA compared to sunflower oil (SFO). Fat and moisture percentages, total fatty acid profiles and TBARS were analysed. Fatty acid profiles were altered in the sausages following all treatments. While a stronger effect was seen for CLA treatments, addition of SFO in the diet also resulted in linear increases of CLA in the sausages. CLA supplementation resulted in increased saturated fatty acid content; however, all treatments were within the recommended polyunsaturated/ saturated fatty acid ratio of above 0.4. Improved oxidative stability was observed in sausages from CLA supplemented diets.

A semi-quantitative SDS-PAGE method was standardised for the routine analysis of myofibrillar protein fragments, 30 and 110 kDa, associated with the meat tenderisation process. Bovine serum albumin was used as an internal standard. Standard curves for purified proteins demonstrated a linear response using this method. Mean analytical recoveries were 95.5 and 102.8% for separation on 7.5 and 15% acrylamide gels, respectively. The ability of the test to measure 30 kDa and 110 kDa fragments independently of sample volumes was demonstrated. Quality control studies showed that levels of 110 kDa protein fragment quantified on 7.5% gels varied by 23.1% within gels and 36.4% between gels. Quantification of 30 kDa protein fragment on 15% gels varied by 7.3% within gels and 7.0% between gels. This thoroughly standardised SDS-PAGE method may be used to measure 30 and 110 kDa bands in extracts of bovine M. longissimus dorsi over the post-mortem ageing period and to evaluate other quantitative methods developed in the future for measurement of the same protein fragments.

Hereford cross heifers ( n =3) were slaughtered and hung conventionally. At 1 h post-mortem the M. longissimus dorsi (LD) was excised, vacuum packaged in plastic bags and stored at 4°C. Samples were taken from each of eight different locations along the length of the LD muscle at 1 h, 1, 3 and 15 days post-mortem for extraction using 5% TCA. Supernatants were stored at −20°C until analysis by HPLC. Peptides produced during the storage of beef were isolated by high performance liquid chromatography (HPLC). Results show that these components increase in quantity from 1 h to 15 days post-mortem. Five fractions were collected which correspond to various peaks of interest. These fractions were subsequently analysed by mass spectrometry and amino acid sequencing to reveal their identity. Fractions 1 and 2 were found to be mixtures of low molecular components. Fractions 3, 4 and 5 were found to be proteolytic fragmentation products of glyceraldehyde-3-phosphate dehydrogenase, troponin T and creatine kinase, respectively. Enhanced appearance of proteolytic fragments from these parent proteins with muscle ageing suggest that they may be useful indicators of meat quality. Further work incorporating sensory and/or texture evaluation of muscle tissue is required to investigate this issue

Proteolysis of myofibrillar proteins results in an increase in substrate made available for the release of free amino acids. Levels of these amino acids have previously been determined in different muscles over the post mortem ageing period in beef. However, there is a shortage of information available regarding variations within a muscle over this ageing period. The objective of this study was to carry out preliminary investigations into the free amino acid levels in eight locations along the M. longissimus dorsi (LD) over the post mortem ageing period. Free amino acids were analysed in the LD of three Hereford cross heifers at 1 h, 1, 3 and 15 day post mortem. In general most amino acids increased in all locations over the ageing period while a 100% increase was observed in total amino acids averaged over the eight locations. More variations occurred between locations in the earlier post mortem period, however, there were no consistent differences during ageing which might suggest variations in proteolytic activity along the LD. As these analyses were carried out on three animals a larger number of animals would need to be sampled to verify these results.