Edi Piasentier

Organic label as an identifier of environmentally related quality: A consumer choice experiment on beef in Italy

This paper uses a hypothetical choice experiment to investigate Italian consumer preferences and willingness-to-pay (WTP) for organic, conventional and genetically modified (GM)-fed beef, utilizing intrinsic, search cues (price, color and visible fat) and extrinsic, credence cues. Data are gathered from three different locations in northern, central and southern Italy using a sequential Bayesian approach. Results showed that consumers attach higher value to organic meat. WTP for GM-fed beef, which is not yet sold in Italy, is well below current conventional beef prices. Organic beef is attractive to consumers because it is associated with higher animal welfare standards and environment-related issues (food miles and biodiversity preservation). No differences are found in marginal WTP estimates by gender, age, education, being a parent or having a higher level of knowledge about organic production. Ethical/environmental issues (credence cues) appear to be more relevant in explaining variation in WTP for organic beef than ordinary product characteristics (search cues).

Meat texture of lambs from different European production systems

Measurements of meat texture (Warner-Bratzler shear force, WBSF), compression stress at 20% (S20) and 80% (S80) of initial sample thickness, sarcomere length, pH, and sensory tenderness score were determined on the longissimus muscle from lambs from 22 diverse European lamb types from 6 countries. Carcasses chilled to minimise cold shortening. The types ranged from 1-month-old milk-fed lambs to 1-year-old heavy wether lambs reared on the transhumance system (extensive system based on moving animals from valleys to high mountains in search of seasonal resources). Overall, it seems that breed was more important in influencing meat toughness than age or gender. Within breed, there was some evidence of an age effect (the older the animal the tougher the meat), and nutritional handling was, in some cases, significant. The lowest WBSF values were for meat from 16-kg carcasses of pasture-fed animals of the Icelandic breed (average 1.7 kg) and the highest were for meat from 19–20 kg carcasses of the Bergamasca breed (average 4.1 kg). The two youngest types had the highest values for S20 (10.5 and 11.8 N/cm2), the compression value related to myofibrillar component. There was a very good agreement between panels from the different countries in the ranking of tenderness; meat from the Icelandic breed was the most tender and that from the Bergamasca breed the least, in concurrence with the WBSF results, with a significant relationship between tenderness and WBSF values in all the lamb types studied.

Rapid characterization of dry cured ham produced following different PDOs by proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS)

In the present study, the recently developed proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS) technique was used for the rapid characterization of dry cured hams produced according to 4 of the most important Protected Designations of Origin (PDOs): an Iberian one (Dehesa de Extremadura) and three Italian ones (Prosciutto di San Daniele, Prosciutto di Parma and Prosciutto Toscano). In total, the headspace composition and respective concentration for nine Spanish and 37 Italian dry cured ham samples were analyzed by direct injection without any pre-treatment or pre-concentration. Firstly, we show that the rapid PTR-ToF-MS fingerprinting in conjunction with chemometrics (Principal Components Analysis) indicates a good separation of the dry cured ham samples according to their production process and that it is possible to set up, using data mining methods, classification models with a high success rate in cross validation. Secondly, we exploited the higher mass resolution of the new PTR-ToF-MS, as compared with standard quadrupole based versions, for the identification of the exact sum formula of the mass spectrometric peaks providing analytical information on the observed differences. The work indicates that PTR-ToF-MS can be used as a rapid method for the identification of differences among dry cured hams produced following the indications of different PDOs and that it provides information on some of the major volatile compounds and their link with the implemented manufacturing practices such as rearing system, salting and curing process, manufacturing practices that seem to strongly affect the final volatile organic profile and thus the perceived quality of dry cured ham.

Multielement (H, C, N, O, S) stable isotope characteristics of lamb meat from different Italian regions

The study focuses on the (2)H/H, (13)C/(12)C, (15)N/(14)N, (18)O/(16)O and (34)S/(32)S values of defatted dry matter (DFDM) and on the (2)H/H, (13)C/(12)C and (18)O/(16)O values of the fat fraction of meat samples from various lamb types reared in seven Italian regions, following different feeding regimes (forage, concentrate, milk). The (13)C/(12)C (r = 0.922), (2)H/H (r = 0.577) and (18)O/(16)O (r = 0.449) values of fat and DFDM are significantly correlated, the fat values being significantly lower for C and H and higher for O than for DFDM values and the differences between the two fractions not being constant for different lamb types. The feeding regime significantly affected the (13)C/(12)C, (15)N/(14)N, (18)O/(16)O and (2)H/H of fat. The DFDM (2)H/H, and (18)O/(16)O values, excluding an outlier, are significantly correlated with the corresponding values in meteoric waters, thus allowing us to trace the variability of geoclimatic factors. (15)N/(14)N is influenced by pedoclimatic conditions, whereas (34)S/(32)S is influenced by the sea spray effect and the surface geology of the provenance area. By applying stepwise linear discriminant analysis only the (2)H/H of fat was found not to be significant and 97.7% of the samples were correctly assigned to the lamb type and more than 90% cross-validated. With the feeding regime, 97.7% of the samples were both correctly assigned and cross-validated using a predictive model including (13)C/(12)C, (15)N/(14)N, (18)O/(16)O, (34)S/(32)S of DFDM and (18)O/(16)O of fat.

The n-alkane concentrations in buds and leaves of browsed broadleaf trees

The concentration of n-alkanes in the cuticular wax of plants can be used to estimate the composition of the diet selected by free-ranging animals. The aims of this study were to characterize the n-alkane profiles of developing leaves and evaluate the degree of chemical discrimination between six browsed broadleaf, tree species: European ash (Fraxinus excelsior L.), flowering ash (Fraxinus ornus L.), hornbeam (Carpinus betulus L.), hazel (Corylus avellana L.), mountain ash (Sorbus aucuparia L.) and beech (Fagus sylvatica L). The effect of the stage of development was examined by considering five different vegetative stages: dormant bud (DB), late bud (LB), young leaf (YL), mature leaf (ML) and senescing leaf (SL). Five samples per each vegetative stage and species, gathered in a mixed woodland of the Italian Eastern Alps between February and October, were analysed for their n-alkane concentrations (C 23 -C 36 ). The residual coefficient of variation was 15.5 % on average for the individual n-alkanes considered. There were noticeable differences in individual and total n-alkanes content between species. In particular, C 27 was the predominant n-alkane in beech and C 33 was found in high proportions in the two species of Fraxinus; hazel and flowering ash had a higher total n-alkanes content than the overall mean, while the lowest values were found in hornbeam and beech. The n-alkane profile also underwent important changes during the vegetative development, with different extent and direction according to the species. In the three successive leaf stages, a tendency for a progressive increase in the longest chain homologues was observed. In any case, the young leaf stage differed most from the contiguous stages. Canonical discriminant analysis indicated that the n-alkane profile of buds and leaves were mathematically distinguishable and the chemical differences between species were persistent over the plant vegetative development.

Comparison of n-alkanes and chromium oxide methods for estimating herbage intake by grazing dairy cows

The experiment was conducted on an alpine pasture composed predominantly of gramineae (more than 62% of ground cover) with 18 lactating Brown Swiss cows (average yield 21.0 kg FCM, SD 3.14), which received a supplement of concentrates according to their milk production (range 1.5–8.0 kg day−1). Herbage intake was estimated for all the animals with the chromium oxide method (twice-daily dosing), associated with the in vitro OM digestibility, and with the n-alkane method, using C31 as the internal marker and C32 as the external marker (once-daily dosing). The sampling of the herbage by hand plucking and the faeces (four grab samples per day) was performed for 5 consecutive days. In order to evaluate the variability of the markers excretion, the daily samples of faeces from six animals were analysed separately. The repeatability within day of the faecal concentration of the n-alkanes was higher than that for the chromium oxide (0.41, 0.48 and 0.55 for C31, C32 and the C31C32 ratio, respectively vs. 0.18 for the chromium oxide). The highest proportion of the variation in the estimated intake was associated with the differences between days for the n-alkane method (54.6% of the total), while the samplings within days were more important for the chromium oxide technique (67.0% of the total). On average, herbage intake estimated with the two methods coincided if the recovery of the chromium oxide was assumed to be 95.5%. The correlation between estimates was 0.62∗∗ and did not appear to be influenced by the level of concentrates in the diet. Considering the mode of executing the two methods under comparison, it was concluded that the n-alkane technique is easier to perform and less laborious.

Effect of whole linseed addition on meat production and quality of Italian Simmental and Holstein young bulls

The effect of long term dietary linseed addition on performance, carcass characteristics and meat quality of Italian Simmental (IS) and Italian Holstein (HI) young bulls was investigated. Thirty-two animals were assigned to 4 groups following a factorial design: 2 breeds - IS and IH - ×2 diets - containing whole ground linseed (5-8% of DM) and control. IS had greater in vivo performance and carcass characteristics than IH. IS muscle had lower C14:0, C16:0, SFA, higher C18:2n-6 cis, PUFAn-6, PUFA and PUFA/SFA proportion than IH in phospholipids (PL) fraction. Linseed inclusion did not affect animals performance and carcass characteristics. In muscle PL, linseed increased C20:0, C22:0, C23:0, C20:5n-3 and decreased C20:4n-6, PUFAn-6/n-3, PUFAn-6 concentration. Linseed decreased C14:0, C16:0 proportion in neutral lipids (NL) and increased total PUFAn-3, C18:3n-3 proportions both in NL and PL fraction. However, these differences were relatively low from a quantitative point of view.

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.

Association analyses of single nucleotide polymorphisms in the LEP and SCD1 genes on the fatty acid profile of muscle fat in Simmental bulls

The aim was to investigate the effect of the genetic polymorphisms of leptin (LEP) and stearoyl-CoA desaturase (SCD1) genes on the fatty acid (FA) composition of the muscle of 103 Simmental bulls. Ten single nucleotide polymorphisms (SNP) were detected in exons 2 and 3 of the LEP gene, two of them encoding non-synonymous mutations. Allelic substitution effects of all the SNP on 28 single fatty acids, monounsaturated (MUFA) and polyunsaturated (PUFA) and desaturation indexes were estimated. Both the SCD1 SNP, as well as three SNP of the leptin gene, affected, to different extents, the desaturation of FA into MUFA. Because it was previously proposed that leptins metabolic action involves down-regulation of SCD1, it is possible that, beyond the mere additive effect of SCD1 gene on FA desaturation, the non-synonymous mutations in the leptin gene also contribute to the variability of FA composition in muscle fat.

Candidate gene markers involved in San Daniele ham quality.

San Daniele dry-cured hams (also known as prosciutto) are produced in the Northeastern region of Italy. This high value product requires high quality fresh meat to avoid processing problems. The Sterol Regulatory Element Binding Protein-1 (SREBF1) is a transcription factor involved in the regulation of fatty acid synthesis in muscle and adipose tissues. The SREBF1 gene, its regulating genes SCAP and MBTPS1, and one of its target genes, SCD, were investigated for associations with several meat quality traits of San Daniele hams. Significant associations of some gene markers were found with carcass weight, lean percentage, backfat thickness, ham green weight, ham fat cover thickness, shear force (WBSF), salting losses and instrumental colour of both lean and fat. These findings provide initial evidences that SNPs in SREBF1, SCAP, MBTPS1 and SCD are associated with San Daniele ham quality and may be considered as markers for selective breeding programs.