Ada Braghieri

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).

Effect of information about animal welfare on consumer willingness to pay for yogurt.

This study aimed to verify whether consumers confirm their willingness to pay extra costs for higher animal welfare standards in a situation where a potential purchase performed by consumers, such as the Vickrey auction, is used. A 104-member consumer panel was asked to rate its willingness to pay (WTP) for plain and low-fat yogurts in 3 information conditions: tasting without information (blind WTP), information about animal welfare without tasting (expected WTP), tasting with information about animal welfare (actual WTP). Information was provided to the consumers under the form of labels indicating the level of animal cleanliness and freedom of movement (5-point scale, from poor to very good). Consumers were influenced by information about low standards of animal welfare (low cleanliness and low freedom of movement) and moved their willingness to pay in the direction of their expectations. However, the discrepancy between expectancy and actual WTP was not totally assimilated, indicating that WTP was also expressed in relation to other aspects (e.g., the sensory properties of the products). Conversely, the information concerning high standards of animal welfare (high cleanliness and high freedom of movement) was able to affect expectancy but had an effect on actual WTP only when the most acceptable yogurt was offered to the consumers. In the case of discordant information on animal welfare, partly indicating high levels of welfare (freedom of movements) and low levels of welfare (cleanliness), expected WTP was always lower than blind WTP. However, when the least acceptable product was presented, they completely assimilated their actual WTP to the expectations. Conversely, with the most acceptable yogurt, no assimilation occurred and sensory properties prevailed in orienting consumer WTP. Within each product, consumers expressed a higher WTP for products with labels indicating high welfare standards as compared with yogurts with labels reporting intermediate and low welfare standard. These results show that information about animal welfare, if given to the consumers, can be a major determinant of consumer WTP for animal-based food products. However, information about high standards of animal welfare should be paired with products presenting a good eating quality.

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).

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.

Composition and sensory profiling of probiotic Scamorza ewe milk cheese

The present study aimed to assess the effect of the addition of different usually recognized as probiotic bacterial strains on chemical composition and sensory properties of Scamorza cheese manufactured from ewe milk. To define the sensory profile of Scamorza cheese, a qualitative and quantitative reference frame specific for a pasta filata cheese was constructed. According to the presence of probiotic bacteria, cheeses were denoted S-BB for Scamorza cheese made using a mix of Bifidobacterium longum 46 and Bifidobacterium lactis BB-12, and S-LA for Scamorza cheese made using Lactobacillus acidophilus LA-5. The designation for control Scamorza cheese was S-CO. Analyses were performed at 15d of ripening. The moisture content of Scamorza ewe milk cheese ranged between 44.61 and 47.16% (wt/wt), showing higher values in S-CO and S-BB cheeses than in S-LA cheese; the fat percentage ranged between 25.43 and 28.68% (wt/wt), showing higher value in S-LA cheese. The NaCl percentage in Scamorza cheese from ewe milk was 1.75 ± 0.04% (wt/wt). Protein and casein percentages were the highest in Scamorza cheese containing a mix of bifidobacteria; also, the percentage of the proteose-peptone fraction showed the highest value in S-BB, highlighting the major proteolysis carried out by enzymes associated with B. longum and B. lactis strains. Texture and appearance attributes were able to differentiate probiotic bacteria-added cheeses from the untreated control product. In particular, S-BB and S-LA Scamorza cheeses showed higher color uniformity compared with S-CO cheese. Furthermore, the control cheese showed higher yellowness and lower structure uniformity than S-BB. The control product was less creamy and grainy than S-BB; conversely, the inclusion of probiotics into the cheese determined lower adhesivity and friability in S-BB and S-LA than in S-CO. This study allowed the definition of the principal composition and sensory properties of Scamorza ewe milk cheese. The specific quantitative vocabulary for sensory analysis and reference frame for assessor training also established in this study should be implemented to systematically monitor the quality of this new typology of ewe milk cheese.

Effect of forage to concentrate ratio on growth performance, and on carcass and meat quality of Podolian young bulls

The effect of forage to concentrate ratio: 60-40 [high concentrate group (HC) and 70-30 [low concentrate group (LC)] on growth, slaughtering performance and meat quality were evaluated in twenty organically farmed Podolian young bulls. Meat quality characteristics were measured on three different muscles [Longissimus dorsi (LD), Semimembranosus (SM) Semitendinosus (ST)], vacuum-packaged and chilled stored at 2-4°C for 15 days. The animals in the HC group had higher weight gain than those in the LC group (P<0.05). Slaughter data were not influenced by ration composition. The higher forage to concentrate ratio produced an improvement in fatty acid composition of the three muscles, with a higher polyunsaturated to saturated ratio (P<0.001). Vitamin E and malondialdehyde (MDA) contents were not affected by the feeding treatment. Panel scores for tenderness and flavour (P<0.01) and Warner-Bratzler Shear force (P<0.001) were significantly affected by muscle, the LD muscle being the most tender and the richest in flavour but they not affected by dietary treatment.

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.

Cheese liking and consumer willingness to pay as affected by information about organic production.

The present study aimed to assess the effect of information about organic production on Pecorino cheese liking and consumer willingness to pay. Mean scores of perceived liking were similar for organic cheese (OC) and conventional cheese (CC). Expected liking scores were higher for OC than for CC (P<0.001). For OC the expected liking was significantly higher (P<0.001) than the perceived liking expressed in blind conditions (negative disconfirmation), whereas for CC the expected liking was significantly lower (P<0.001) than the perceived liking expressed in blind conditions (positive disconfirmation). Consumers assimilated their liking for OC in the direction of expectations, as the difference actual vs. perceived liking was significant (P<0.001). However the assimilation was not complete, as also the difference actual liking vs. expected liking was significant (P<0.001). Consumers showed a willingness to pay OC (mean+/-se=4.20+/-0.13 euro/100 g) higher than the local retail price for conventional (1.90 euro/100 g) and even organic cheese (3.00 euro/100 g). We conclude that the information about organic farming can be a major determinant of cheese liking and consumer willingness to pay, thus providing a potential tool for product differentiation, particularly for small scale and traditional farms.

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.

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).