Anna Badiani

Objective measurements of pork quality: Evaluation of various techniques

Research has been undertaken in which various methods for meat quality evaluation were compared. The measures used were pH (by homogenization and by combined electrode), light scattering conductivity, dielectric loss factor and colour. A very low incidence of PSE (Pale, Soft, Exudative) and DFD (Dark, Firm, Dry) cases was observed and the correlation between pH, as measured by homogenization and by combined electrode, did not appear to be completely satisfactory. Dielectric loss factor, as measured by the MS tester, seems to be specifically suited for PSE diagnosis. On the other hand, higher values of light scattering and conductivity measured at 24 h post mortem, are found to be linked to the rate of pH fall, even outside the range for PSE. Colour measurements, especially of the parameters L(∗), a(∗) and hue angle, have given interesting information. In fact, meat could be classified by colour intensity (a(∗), psychometric chroma), by type of colour (hue angle) and by exudative phenomena (L(∗)). No marked effects of rearing techniques have been observed, whereas the genetic background appears to influence some colour parameters. Slaughter conditions, on the other hand, could affect markedly all the meat quality parameters measured in this research.

The effect of journey time and stocking density during transport on carcass and meat quality in rabbits

Four hundred and fifty hybrid commercial rabbits (half males and half females) at the end of their productive cycle (82 days old) were transported in cages (98×52×24cm, length×width×height) at high or low density (75.5 or 49.0kg/m(2) - 15 or 10 animals per cage) on an uncovered truck for 1, 2 or 4h. Live weight before and after transport as well as slaughter data were recorded for each rabbit. A subset of 180 carcasses were evaluated for meat quality on the basis of meat pH, colour (CIELab system), cooking loss, drip loss and shear force. As a representative of the whole carcass muscle/bone ratio, the left hind leg was separated, dissected and its meat analysed in order to determine its water, protein, ash and lipid content. It was found that a longer journey significantly increases the live weight losses (3.3% vs. 2.0% vs. 1.6% for 4, 2 or 1h, respectively; P<0.001), as a result not only of urine and fecal losses, but also of a decrease in carcass weight (P<0.01) during transport. Ultimate pH (pH(u)) was higher and pH drop lower in rabbits transported for 4h compared to those transported for 2h (P<0.05). Moreover, the meat from animals that had undergone the longest journey was more purple-red (P<0.05), darker (P<0.0001), and firmer when raw and showed less cooking loss than meat from those that underwent shorter journeys. Transport density did not influence any of the considered parameters and there was no interaction between transport time and density.

Objective evaluation of pork quality: Results of on-line measurements

Research has been conducted on objective pork quality evaluation on line in an industrial slaughterhouse. The investigation, which involved more than 5000 pigs, lasted for 12 working days spread over four consecutive weeks between October and November. Measurements performed were Fat-o-Meater carcass classification (lean content, fat and muscle thicknesses), cold carcass weight, 24-h pH of Semimembranosus and Biceps femoris muscles and 24-h colour of Semimembranosus muscle. The results show that cold carcass weight and lean content are only slightly related to meat quality as evaluated by pH and colour. Cluster analysis has confirmed the importance of pH and colour parameters, such as L(∗), a(∗) and hue angle, for the evalaution of pork quality on line in an industrial context.

Use of centrifuged and preserved microalgae for feeding juvenile Manila clam (Tapes philippinarum): effects on growth and fatty acid composition

Abstract The objective of the present study was to assess the nutritional value of three diets containing commercial preserved microalgae pastes and the relationship of their biochemical composition to the growth rate and fatty acids profile of juvenile Tapes philippinarum. The feeding period was 6 weeks. At a daily ratio of 1% dry weight live weight of the clams–1, the trispecific diet with 40% of I. galbana, 20% of T. suecica and 40% of C. muelleri supported greater growth of animals than either a mixture of 80% of I. galbana and 20% T. suecica or I. galbana alone (P< 0.05). Even the fatty acid profile was significantly modified depending on the composition of the diets. In particular a decrease of EPA was observed in clams with the lowest growth rate.

Effect of Light Exposure on Lipid and Colour Stability of Southern and Northern European Type Sausages

E. Zanardi1*, V. Dorigoni1 , R. Chizzolini1 and A. Badiani2 1Department of Animal Production, Veterinary Biotechnology, Quality and Safety of Food, University of Parma, Parma; 2Department of Veterinary Morphophysiology and Animal Production, University of Bologna, Ozzano Emilia (BO), Italy. *Correspondence: Department of Animal Production, Veterinary Biotechnology, Quality and Safety of Food, University of Parma, 43100 Parma, Italy E-mail: emanuela.zanardi@unipr.it