A. Girolami

Fatty acid profile, cholesterol content and tenderness of ostrich meat as influenced by age at slaughter and muscle type.

Ten Blue Neck ostriches were used to study the effect of age at slaughter (10-11 and 14-15 months) and muscle on fatty acid profile, cholesterol content and texture of meat. Fatty acid profile of ostrich meat was significantly affected by age at slaughter (P<0.001) and muscles (P<0.001). Different age at slaughter (10-11 vs. 14-15 months) produced an increase of P/S ratio (P<0.001), total saturated (P<0.05) and monounsaturated (P<0.001) fatty acids. The highest percentage of saturated and monounsaturated fatty acids were found in M. iliofibularis (P<0.001), whereas M. gastrocnemius showed the highest content of polyunsaturated fatty acids (P<0.001). Analysis of variance of data on cholesterol content (mg/100 g of meat) showed no significant effects of age at slaughter and muscle location. No effect of age on shear values was observed, whereas sensory panellists scored meat from younger birds as more tender (P<0.001). Both instrumental and sensory evaluation indicated that meat from M. iliofibularis was more tender (P<0.001).

Fatty acid profile, cholesterol content and tenderness of meat from Podolian young bulls

Fatty acid profile, cholesterol content and sensory properties of meat from Podolian young bulls were evaluated. The percentage of saturated fatty acids was higher for LD and lower for SM and ST muscles (P<0.001). Oleic and stearic fatty acids constituted more than 50% of the total fatty acids in all muscles studied. The meat produced by Podolian young bulls showed a favourable percentage content of polyunsaturated fatty acids and a beneficial ratio P/S. Conversely, the ratio n-6/n-3 exceeded the recommended value in the human diet. Changing the time of ageing from 8 to 15 days produced an increment of MDA (P<0.01). The differences in MDA content observed between meat samples aged 8 and 15 days were still detectable after 4 and 8 months of frozen storage. The extension of the ageing period from 8 to 15 days produced an increase in tenderness (P<0.05) and flavour intensity (P<0.01).

Effect of artificial rearing on lamb welfare and meat quality

Twenty male Comisana lambs were equally divided into two groups. Ten subjects were artificially reared, 10 others were ewe reared and used as control. Unseparated control animals displayed increased cellular immune response to a percutaneous injection of phytohemagglutinin (P<0.001). During the open field test, ewe-reared lambs showed a higher number of flight attempts (P<0.01). Carcass yield were higher for artificially reared animals (P<0.05). Conversely, legs of ewe-reared animals had significantly more fat (P<0.05) and a higher content of saturated fatty acids (P<0.001). Polyunsaturated fatty acid content was higher in artificially reared lamb meat (P<0.01), although the ratio n-6/n-3 was well above the recommended values. The triangle test showed a significant difference in sensory analysis between the two products (P<0.05). Finally, for both rearing systems legs without subcutaneous fat showed a higher percentage of polyunsaturated fatty acids and a corresponding lower content of saturated fatty acids (P<0.001).

Effect of age at slaughter on carcass traits, fatty acid composition and lipid oxidation of Apulian lambs

Abstract Twenty Apulian ram lambs were used to study the effect of the age at slaughter (45 and 90 days) on carcass traits, fatty acid composition and lipid oxidation. Carcasses were dissected in commercial cuts and stored frozen (−20°C) for 6 months. Carcass yield was higher for animals slaughtered at 45 days (P

Measurement of meat color using a computer vision system

The limits of the colorimeter and a technique of image analysis in evaluating the color of beef, pork, and chicken were investigated. The Minolta CR-400 colorimeter and a computer vision system (CVS) were employed to measure colorimetric characteristics. To evaluate the chromatic fidelity of the image of the sample displayed on the monitor, a similarity test was carried out using a trained panel. The panelists found the digital images of the samples visualized on the monitor very similar to the actual ones (P<0.001). During the first similarity test the panelists observed at the same time both the actual meat sample and the sample image on the monitor in order to evaluate the similarity between them (test A). Moreover, the panelists were asked to evaluate the similarity between two colors, both generated by the software Adobe Photoshop CS3 one using the L, a and b values read by the colorimeter and the other obtained using the CVS (test B); which of the two colors was more similar to the sample visualized on the monitor was also assessed (test C). The panelists found the digital images very similar to the actual samples (P<0.001). As to the similarity (test B) between the CVS- and colorimeter-based colors the panelists found significant differences between them (P<0.001). Test C showed that the color of the sample on the monitor was more similar to the CVS generated color than to the colorimeter generated color. The differences between the values of the L, a, b, hue angle and chroma obtained with the CVS and the colorimeter were statistically significant (P<0.05-0.001). These results showed that the colorimeter did not generate coordinates corresponding to the true color of meat. Instead, the CVS method seemed to give valid measurements that reproduced a color very similar to the real one.

Sensory evaluation of young goat meat

Loins from 12 young goats (three extensively reared-entire males, EE; three extensively reared-castrated males, EC; three intensively reared-entire males, IE; four intensively reared-castrated males, IC) were assessed by a trained panel of eight assessors for odour, flavour and texture using 100 mm unstructured scales. Procrustes analysis was used to produce the spatial configuration of the samples. The first principal axis explained 44.9% of the variation and was mainly based on textural attributes. The second principal axis accounted for 21.3% of the variation and was mainly related to odour and flavour. Samples obtained from groups EE and EC were more tender and juicy, whereas, IE animals produced a more cohesive meat. Groups IE and IC produced a more stringy meat, with a higher meaty odour and flavour. The rearing system affected texture more than odour and flavour, whereas sex had little effect on textural attributes compared with odour and flavour.

Behaviour and meat production of organically farmed unweaned lambs

Twenty Sarda male lambs, equally divided into two groups, were used to evaluate the effect of artificial rearing on animal behaviour and meat production. Artificially reared lambs showed an altered behavioural pattern with increased suckling attempts (P<0.001) and levels of social interactions with peers (P<0.05). In the open field test, they also displayed withdrawal behaviour in terms of reduced time of locomotion (P<0.05) and increased latency time to the first movement (P<0.05). Ewe-reared lambs showed a higher growth rate and produced more valuable carcasses. It was concluded that dam-rearing, which is compulsory in organic farming (EU Regulation 1804/1999), can improve carcass quality and affect animal behaviour, which, in turn, is a widely used welfare indicator.

Effect of information about animal welfare, expressed in terms of rearing conditions, on lamb acceptability

The present study was aimed to assess the effect of information about the farming system and welfare of artificially (AR) and ewe-reared lambs (ER) on meat acceptability. An 84-consumer panel was asked to give three types of evaluation for both products: tasting without information (perceived liking); information without tasting (expected liking); tasting with information (actual liking). For both products, the expected liking was significantly different from the perceived liking (P<0.001), thus indicating that a disconfirmation occurred. The consumers found ER meat worse than expected (negative disconfirmation) and AR meat better than expected (positive disconfirmation). No significant difference between perceived and actual liking was observed for ER lamb (P>0.05), whereas, for the meat produced by AR lambs actual liking was lower than perceived liking (P<0.001). However, consumers did not completely assimilate their liking in the direction of expectations, as indicated by the fact that expectancy for AR lamb was significantly lower than actual acceptability (P<0.001). Mean scores of perceived liking were higher for the meat produced by AR animals as compared to ER lambs (P<0.05). Conversely, expected and actual liking scores were higher for meat from ER lambs than for meat from AR animals (P<0.001 and P<0.05, respectively). These results show that information about animal welfare, expressed in terms of rearing conditions, can be a major determinant of animal-based food acceptability, thus providing a potential tool for meat differentiation.

Methodological approach to evaluate the effects of age at slaughter and storage temperature and time on sensory profile of lamb meat

A methodological approach, that requires the use of an experimental design, the definition of a sensory profile and an appropriate statistic validation of sensory data, was developed, in order to evaluate the effects of some process variables, such as age at slaughter and storage time and temperature, on sensory characteristics of lamb meat. In this study factorial design (2(3)) was used. The first step was the definition of descriptive terms for determining the sensory profile of meat. A vocabulary of 10 descriptive terms of odour, flavour and texture was developed. Therefore, after an appropriate and rigorous training, a panel of 8 assessors evaluated the lamb products in triplicate using a 100 mm unstructured scale. The following step was the statistic validation of data. Sensory data for each attribute were submitted to a fixed analysis of variance. Results showed that even though the panel was trained, judgements differed among assessors, as demonstrated by the significant assessor x sample interaction which was found for most attributes. In order to minimise this effect, the sensory data were submitted to a mixed analysis of variance that allows the determination of panel performance and selection of significant attributes for sample discrimination. Eight attributes were selected. Finally, analysis of variance with age, frozen temperature and storage time as main effects, was performed on mean values of selected attributes. Meaty odour and flavour, cohesiveness and stringiness were negatively influenced by age, whereas tenderness and juiciness were positively influenced by age. Lamb odour and flavour were positively influenced by frozen temperature. At increasing storage time, meaty odour and flavour and juiciness increased. The descriptive analysis allowed an objective description of the products in terms of perceived sensory attributes. The fixed and mixed models of analysis of variance produced different results. A mixed model appeared to be suitable for validation of panel performances and selection of significant attributes for meat samples discrimination.

Chemical, physical and sensory properties of meat from pure and crossbred Podolian bulls at different ageing times.

The present study aimed to investigate the effect of crossbreeding with Limousine sires on fatty acid profile, physical and sensory properties of meat produced by Podolian young bulls. Polyunsaturated fatty acid content was influenced by crossbreeding (P<0.01) with Podolian bulls (P) producing beef characterised by a higher level of unsaturation in comparison with crossbred animals (LP). As a consequence, P/S ratio was significantly higher in meat produced by P animals than LP (P<0.01). P animals had higher linoleic (P<0.05), linolenic (P<0.05), EPA (P<0.05) and DHA acids (P<0.001) levels than LP subjects. No breed effect was observed for the ratio n-6/n-3 (P>0.05). WBS force of LD was significantly lower in meat from crossbred subjects (P<0.05). Both crossbreeding with Limousine and extension of ageing from 2 to 7 days improved LD tenderness as assessed by panel taste (P<0.001).