C: Food Chemistry Effect of the Type of Oil on the Evolution of Volatile Compounds of Taralli During Storage Mariagrazia Giarnetti, Francesco Caponio, Vito M Paradiso, Carmine Summo, and Tommaso Gomes Abstract: Baking process leads to a huge quantity of newly formed volatile compounds, which play a major role in developing the ﬂavor of the ﬁnal product. The aim of this work was to investigate on the evolution of the volatile proﬁle of taralli as a function of both the kind of oil used in the dough and the storage time. The volatile compounds from the taralli were extracted by headspace solid-phase microextraction and analyzed by gas-chromatography/mass spectrometry (GC/MS). Forty-four volatile compounds were identiﬁed in taralli, most of which produced by thermically induced reactions occurring during baking process, such as volatiles deriving from Maillard reaction and/or sugar degradation and lipid oxidation. The results obtained demonstrated the essential role played by the type of oil on the formation and on the release of volatile compounds. The volatile compounds signiﬁcantly increased during storage and their individual levels were in most cases signiﬁcantly lower in taralli made with extra virgin olive oil than in those made with reﬁned oils. Finally, the taralli made with extra virgin olive oil, compared with those prepared with other vegetable oils, showed to be more resistant to oxidation, probably due to the presence of natural antioxidants. Keywords: HS-SPME-GC/MS analysis, oil, storage time, taralli, volatile compound Introduction Baking process leads to a huge quantity of newly formed volatile compounds which play a major role in developing the ﬂavor of the ﬁnal product. Volatile compounds in bakery products are mainly the result of the Maillard reaction, but both caramelization and lipid oxidation can also contribute to the volatile proﬁle. In par- ticular, lipid oxidation involves the formation of free radicals and peroxides, whose decomposition can result in the formation of volatile compounds (for example, alcohols, aldehydes, ketones, and short chain fatty acids) among which many have an unpleasant ﬂavor (off-ﬂavor), which render unpalatable and decrease shelf-life of the products (W  asowicz and others 2004). As a consequence, lipid oxidation has been long recognized as a major problem in the storage of foods (Kochhar 1996; Paradiso and others 2009). Several studies have dealt with the identiﬁcation and quantiﬁ- cation of the volatile compounds which have an impact on the ﬂavor of the most common baked cereal products. In particular, Rega and others (2009) monitored endogenous aroma compounds released during the baking of a model cake; Mohsen and others (2009) evaluated the effect of substitution of soy protein isolate on aroma volatiles, chemical composition, and sensory quality of wheat cookies. Poinot and others (2008) studied the inﬂuence of formulation and process on the aromatic proﬁle and physical characteristics of bread; Plessas and others (2008) monitored the quality degradation during storage of breads produced using mixed starter cultures of yeast and lactic acid bacteria; Bianchi and others (2008) evaluated the inﬂuence of different baking modes on the volatile compounds of the Italian Protected Designation of Origin “Altamura” bread; Qu´ ılez and others (2006) investigated on the MS 20111192 Submitted 10/3/2011, Accepted 12/8/2011. Authors are with Dipto. di Biologia e Chimica Agro-Forestale e Ambientale (DIBCA), Univ. degli Studi di Bari Aldo Moro, Via Amendola, 165/a, I-70126 Bari, Italy. Direct inquiries to author Caponio (E-mail: francesco.caponio@agr.uniba.it). relationships between sensory ﬂavor evaluation and volatile and nonvolatile compounds in commercial wheat bread type baguette; Brauss and others (1999) highlighted the effect of fat content, baking time, hydration, and temperature on ﬂavor retention and ﬂavor release in biscuits. Finally, Purcaro and others (2008) stud- ied the possibility to use hexanal as a deterioration index to assess rancidity in bakery foods. No studies have been carried out to assess the inﬂuence of the type of fat used in dough formulation on the volatile com- pounds proﬁle. Fats are one of the key ingredients of some bakery products—especially of those with a high fat content such as bis- cuits, cookies, and taralli (Caponio and others 2006, 2009)—as they perform major functions: they entrap air during mixing, in- terfere with the continuity of starch and protein particles, and emulsify the liquid parts of the formulation (Brooker 1993), con- tributing to volume, texture, and overall palatability of the baked products. In addition, fats are capable of affecting mouthfeel, ap- pearance, and structure, and may act as a ﬂavor precursor, ﬂavor carrier, and ﬂavor release modulator (Drewnowski 1992). Within this framework, the aim of this study was to eval- uate the inﬂuence of different oils, used in the taralli making process, and of the storage time on the volatile compounds, analyzed by means of headspace solid-phase microextraction (HS-SPME) technique coupled to gas-chromatography/mass spectrometry (GC/MS) analysis. Materials and Methods Sample preparation Four type of taralli were produced using 4 different types of oil: olive oil (reﬁned olive oil blended with virgin olive oil in undeﬁned proportions, OO), olive pomace oil (reﬁned olive pomace oil added with virgin olive in undeﬁned proportions, OPO), reﬁned palm oil (RPO), and extra virgin olive oil (EVOO), which is seldom used for this kind of product. Three batches of taralli were made for each type of oil. C  2012 Institute of Food Technologists R  C326 Journal of Food Science  Vol. 77, Nr. 3, 2012 doi: 10.1111/j.1750-3841.2011.02613.x Further reproduction without permission is prohibited