A study was carried out to determine the quality characteristics, antioxidant capacity, oxidative status, and consumer acceptability of chicken meat after dietary administration of a semi-solid olive cake, known as “paté” (pOC), in broilers. pOC is an olive oil industry waste rich in bioactive compounds, such as polyphenols, obtained by mechanical extraction from destoned olives. Two hundred and ninety-seven 22-day-old fast growing (Ross 308) female chicks were randomly assigned to three experimental grower-finisher diets. Each dietary group consisted of three replicates, each with 33 birds. The experimental treatments were: (1) basal control diet (C); (2) C diet supplemented with a low dose of pOC (82.5 g/Kg, L-pOC); and (3) C diet supplemented with a high dose of pOC (165.0 g/Kg, H-pOC). Chicken growth rate increased with increasing pOC concentration in the diet. Polyphenol analyses were performed through liquid-chromatography coupled to tandem mass spectrometry technique (LC-MS/MS). In meat of animals belonging to L-pOC and H-pOC groups, tyrosol and sulphate metabolites of hydroxytyrosol were detected. Meat quality parameters and proximate composition were not affected by the dietary treatment, whereas the antioxidant status and the oxidative stability of meat were positively affected, especially when the highest level of pOC was applied. These results demonstrate that pOC can be recommended in chicken diets to improve performance and meat oxidative status.
Molecular biology techniques have been used for species identification in food of animal origin in relatively recent years. A polymerase chain reaction (PCR) based method, the multiplex PCR, was recently applied to species identification in meat and meat products. It allows co-amplification of separate regions of a single gene or specific fragments, each typical of a different animal species in a single PCR reaction, using different pairs of primers in the same reaction mix. In the present paper, the duplex-PCR technique is proposed to identify bovine and water buffalo DNA in a single PCR assay in milk and mozzarella cheese (a typical Italian cheese, originally made from pure water buffalo milk). Because of its lower cost, undeclared bovine milk is added to water buffalo milk for making different kinds of mozzarella cheese. The results of this experiment indicate the applicability of this method, which showed an absolute specificity for the two species and a high sensitivity even down to low DNA concentrations (1 pg). In bovine and water buffalo mixtures of both milk and mozzarella cheese, the minimum concentration tested was 1% of bovine in water buffalo milk and water buffalo in bovine milk. The importance of the somatic cell content in raw milk is also discussed with special reference to the evaluation of mixtures (milk or cheese) of the two species.
As a result of public health concerns regarding antimicrobial resistance in animal-based food products, conventional poultry companies have turned to ‘raised without antibiotics’ (ABF) and organic farming systems. In this work, we evaluated the influence of rearing systems on antimicrobial susceptibility in E. coli and extended-spectrum β-lactamase (ESLB) E. coli diffusion in conventional (C), organic (O) and antibiotic free (ABF) chicken samples collected from cloacal swabs and skin samples in slaughterhouse. The E. coli isolates from conventional (135), antibiotic-free (131) and organic (140) samples were submitted to the Kirby–Bauer method and ESBL E. coli were analyzed by the microdilution test. Conventional samples showed the highest number of strains resistant to ampicillin (89.6%; p < 0.01), cefotaxime (43.7%; p < 0.01), nalidixic acid (57.8%; p < 0.01), ciprofloxacin (44.4%; p < 0.001), and trimethoprim/sulfamethoxazole (62.2%; p < 0.01), with patterns of multi-resistance to three (35.1%) and to four antimicrobials (31.3%), whereas most of the E. coli isolated from antibiotic-free and organic chicken samples revealed a co-resistance pattern (29.2% and 39%, respectively). The highest number of ESBL E. coli was observed in conventional, in both cloacal and skin samples and the lowest in organic (p < 0.001). Our results are consistent with the effect of conventional farming practices on E. coli antimicrobial resistance and ESBL E. coli number, due to the use of antimicrobials and close contact with litter for most of the production cycle.
4 December 2014 in International Journal of Food Science and Technology