[P2.058] Optimization of almond toasting by using

[P2.058] Optimization of almond toasting by using volatile composition and sensory quality 1 3 1 1 1,2 A. Calin* , A. Verdú , F. Martínez-Sánchez , A.A. Carbonell-Barrachina , L. Vázquez-Araújo 1 2 3 Universidad Miguel Hernández, Spain, Kansas State University, United States, Consejo Regulador de la Denominacione Específicas Jijona y Turrón de Alicante, Spain Turrón is a typical Spanish confection prepared from toasted almonds, sugar and honey. Because turrón is under a Protected Geographical Indication, raw materials must be from Eastern Spain; however, the production of honey and especially almond does not meet current demands. Therefore, manufacturers are using almonds from other countries, especially USA. Toasting is one of the most important unit operations in turrón manufacture. The main objectives of this study were: (i) to compare the volatile composition and sensory quality of almonds from two Spanish cultivars, “Marcona” and “Comuna”, and one US cultivar “California”, toasted using the most popular conditions for traditional revolving ovens (165 ºC and 25 min), and (ii) to optimize the toasting time (12-25 min) for modern convection ovens operating at 200 ºC. The instrumental analyses included: CIEL*a*b* colour coordinates and volatile composition, while products were also evaluated using sensory descriptive analyses. In the first study, a total of 58 compounds were detected in toasted almonds, including ketones, aldehydes, pyrazines, alcohols, aromatic hydrocarbons, furans, pyrroles, terpenes, and linear hydrocarbons. Pyrazines, furans and pyrroles were positively correlated with sensory toasted odour and aroma intensities and were the key compounds of the aroma of toasted almonds. Sensory evaluation proved, contrarily to the expected, that both toasted odour and aroma were more intense in “Comuna” almonds than in “Marcona” and “California” samples. Ten flavour attributes (sweet, bitter, nutty, astringent, toasted, oily, woody, burnt, rancid, and aftertaste) were identified as describing the almond flavour and were evaluated to have the optimal flavour profile of toasted almonds. In the second study, the main pyrazines found were: 2,5-dimethylpyrazine, 2-ethyl-3-methylpyrazine, 2methylpyrazine and 2,4-dimethyl-3-ethylpyrazine. Based on both instrumental and sensory colour and aroma, the recommended toasting time at 200 ºC in convection ovens for “Comuna” and “Marcona” almonds was established at 20 min. Keywords: almond, toasting, volatile compounds, aroma