S: Sensory & Food Quality Gas Chromatographic-Olfactometric Aroma Profile and Quantitative Analysis of Volatile Carbonyls of Grilled Beef from Different Finishing Feed Systems Virginia Celia Resconi, Mar´ ıa del Mar Campo, Fabio Montossi, Vicente Ferreira, Carlos Sa˜ nudo, and Ana Escudero ABSTRACT: In this study, the important odor impact volatiles generated in the meat of grilled beef loin muscle were characterized. Animals were finished in 4 different diet systems: T 1 , pasture (a mixture of Medicago sativa, Trifolium repens, and Festuca arundinacea); T 2 , pasture supplemented with cracked corn grain (offered at 0.6% live weight, LW); T 3 , pasture supplemented with cracked corn grain (offered at 1.2% LW); and T 4 , concentrate (pellets with 85% corn and 12.8% sunflower, on a dry-matter basis) plus alfalfa hay (both ad libitum). Aroma compounds were assessed by dynamic headspace- solid phase extraction (DHS-SPE) and gas chromatographic-olfactometric (GC-O) analysis. Most odorants were carbonyl compounds, some of them reaching high GC-O scores, especially 1-octen-3-one, (E)-2-octenal, methional, and hexanal. A specific quantitative analysis of ketones and aldehydes was conducted through their derivatization with o-(2,3,4,5,6- pentafluorobenzyl) hydroxylamine hydrochloride directly on the headspace trap and analyzed by GC-MS, with the purpose of studying the effect of finishing diet systems. From the 23 carbonyl compounds quantified, 2 were especially affected by the diet system; methional was higher in the treatment based on concentrates, whereas (E,E)-2,4-heptadienal was higher in the treatment based only in pastures. The results are discussed considering previous published productive and quality traits. Keywords: Aroma compounds, gas chromatography-olfactometry, GC-O, aldehydes, ketones, finishing feeds Practical Application: The knowledge of how production factors, such as animal feeding, can affect the flavor of meat is of significant interest toward in achieving a high-quality and differentiated product. The development of more specific and efficient methodologies is necessary to analyze meat aroma compounds, which would be used as routine analysis, that is for product authentication. In the future, the use of this analysis would allow producing and designing specific foods according to different markets. Introduction With the general objective of improving the competitivity of the red meat chain in Uruguay toward the global market, an international project was developed to compare the quality of beef subjected to a range of finishing feed regimes. Such systems can affect raw meat components, among them the fatty acid profile, antioxidant content, flavor precursors or the meat structure, and therefore, they can affect the sensory characteristics and consumer acceptabilitiy of the product (Realini and others 2004; Resconi and others 2010a). The aroma compounds released when we eat meat are important for consumer satisfaction. The knowledge of the compounds responsible of the aroma perception and how their MS 20111421 Submitted 11/24/2011, Accepted 3/14/2012. Authors Resconi, Campo, and Sa˜ nudo are with Faculty of Veterinary, Univ. of Zaragoza, 50013 Zaragoza, Spain. Author Montossi is with Natl. Inst. of Agricultural Research, 45000 Tacuaremb´ o, Uruguay. Authors Ferreira and Escudero are with Faculty of Science, Univ. of Zaragoza, 50009 Zaragoza, Spain. Direct inquiries to author Resconi (E-mail: resconi@unizar.es.). concentration can change according to productions systems is of interest toward achieving a high-quality and differentiated product. The assessment of the aromatic compounds is based on the ex- traction of the volatile fraction and its separation and detection by gas chromatography techniques. The extraction procedures com- monly used are: simultaneous distillation/extraction (SDE), solid- phase extraction (SPE), and solid-phase microextraction (SPME) (Elmore and others 2004a), with important differences between methods. Among them, the dynamic headspace adsorption on solid phase extraction cartridges (DHS-SPE) using a purge-and- trap system, attempts to represent the volatiles that reach the ol- factory receptors in the nose after being released from the matrix (meat) when consumers eat. For the selection and ranking of odorants, it is essential the use of the human nose as a detector at the exit of a chromatographic column (GC-olfactometry). These olfactometric approaches have allowed researches elucidation of the chemical identity of more than 20 meat odor-active compounds from different nature (for example, sulfurous, carbonyls, pyrazines, phenols, organic acids) (d’Acampora Zellner and others 2008). However, important dif- ferences between studies are found, related to the use of different C  2012 Institute of Food Technologists R  S240 Journal of Food Science  Vol. 77, Nr. 6, 2012 doi: 10.1111/j.1750-3841.2012.02720.x Further reproduction without permission is prohibited