Discriminant analysis as a tool to identify bovine and ovine meat produced from pasture or stall-fed animals

Abstract

This work evaluated the reliability of the multivariate statistical analysis to discriminate the feeding system and the species of ruminants using their intramuscular fatty acids (FA) profile. FA composition of 53 meat samples (longissimus dorsi muscle) from animals of different species (sheep and cattle) raised with different feeding systems (pasture and stall-fed) (4 groups overall) was determined and expressed as % fatty acid methyl ester (FAME). A stepwise discriminant analysis (SDA) was applied to the full set of FA to select the variables that best discriminated between feeding systems and animal species. The selected variables were then submitted to a canonical discriminant analysis (CDA) to test the ability of those variables in discriminating against the four groups. Discriminant analysis (DA) was then exploited to classify meat samples. From the 62 initial variables detected in the FA profile, 24 were retained in the SDA. The subsequent CDA developed by using the selected variables, significantly discriminated the four groups (Hotelling's test p < 0.0001) by extracting three canonical functions. Heptadecenoic acid C17:1 c10, seemed to play a pivotal role both in discriminating species and feeding system while some 18:1 isomers (C18:1 c12, C18:1 c13 C18:1 t13/t14) together with CLA c9, t11 and x-3 were important in discriminating feeding systems. Multivariate statistical analysis of FA was able to track both the species and the feeding system of source animals with good accuracy. HIGHLIGHTS The increasing interest in the 'green image' of meat obtained from grass-based systems guides the search for methods to trace the animal feeding system. Extracting more information from the large amounts of meat data provided by laboratory equipment is of utmost importance. Multivariate statistical analysis is able to trace with good accuracy meat samples back to their animal species and feeding system origin.

Odd- and Branched-Chain Fatty Acids in Lamb Meat as Potential Indicators of Fattening Diet Characteristics

“…Our results support those of a recently published research on the validity of the FA profile of meat as a tool to identify the dietary background of lambs by means of discriminant analysis [ 5 ] but also indicate that it is not necessary to use an extensive set of FA in IMF for that purpose. The OBCFA contents in IMF suffice to discriminate the meat samples according to the composition of the diet consumed by the lambs during the fattening period.…”

“…In this regard, there has been a growing research interest in meat authentication in terms of the geographical and dietary background of animals, and several analytical methods have been proposed for that purpose [ 4 ]. Those methods are based on more or less complicated laboratory techniques intended to identify reliable predictors such as fatty acids (FA), volatile compounds, stable isotopes or a variety of metabolites in meat [ 5 , 6 , 7 , 8 , 9 ]. The FA profile of intramuscular fat (IMF) has proven to efficiently discriminate between diets fed to fattening lambs [ 5 ].…”

“…Those methods are based on more or less complicated laboratory techniques intended to identify reliable predictors such as fatty acids (FA), volatile compounds, stable isotopes or a variety of metabolites in meat [ 5 , 6 , 7 , 8 , 9 ]. The FA profile of intramuscular fat (IMF) has proven to efficiently discriminate between diets fed to fattening lambs [ 5 ]. Furthermore, intramuscular FA are directly linked to organoleptic and nutritional attributes of ruminant meat [ 10 , 11 ].…”

Fatty Acid and Multi-Isotopic Analysis (C, H, N, O) as a Tool to Differentiate and Valorise the Djebel Lamb from the Mountainous Region of Tunisia

“…In fact, the SFA C20:0, the C18:1t, Cis-9-trans-11-CLA, and BCFA ( Table 1 ) made it possible to distinguish Djebel lamb meat among the three PSs under study (D, BR, and O). Therefore, our results are consistent with recent studies concerning the possibility to identify the dietary background of lambs by means of a discriminant analysis using the FA profile of meat [ 26 , 27 ]. Furthermore, Monahan et al demonstrated that FA analysis is a successful strategy to differentiate between beef from pasture-raised animals, from those fed a barley-based concentrate, or from those whose diet consisted of grass/concentrate combinations.…”

Differentiation of three sheep breeds which have a genetic relationship by body sizes

“…By using discriminant analysis, Dauda et al [22] can differentiate between several breed sheep in Nigeria, and Hayanti et al [23] can also distinguish the origin of Bali cattle in the Jambi province of Indonesia. Discriminant analisys can also as a tool to identify bovine and ovine meat produced from pasture or stall-fed animals [24]. Based on body size, the results obtained depend on the breed used and genetic similarity.…”