A first approach of using ultrasound as an alternative for blanching in vacuum-packaged potato strips 1 Rivia D.A. Amaral 1,2 , Benedito C. Benedetti 1 , Montserrat Pujolà *2 , Isabel Achaerandio 2 , Mara L.B.Bachelli 1 2 3 1 Postharvest Laboratory, Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas (UNICAMP), 4 Av. Candido Rondon, 501, 13083-875, Campinas, São Paulo, Brazil 5 2 Departament d’Enginyeria Agroalimentària i Biotecnologia, Universitat Politècnica de Catalunya 6 BarcelonaTech (UPC), C/Esteve Terradas, 8, 08860 Castelldefels (Barcelona), Spain 7 8 Contact information for corresponding author 9 *Montserrat Pujolà 10 Departament d’Enginyeria Agroalimentària i Biotecnologia, Universitat Politècnica de Catalunya 11 BarcelonaTech (UPC), C/Esteve Terradas, 8, 08860 Castelldefels (Barcelona), Spain 12 Tel. +34 93 552 10 16, fax. +34 93 552 11 21 13 montserrat.pujola@upc.edu 14 15 16 ABSTRACT: The effect of ultrasound (US) (40 kHz, 200 W, 3 min), blanching (85 ˚C, 3.5 min) and the 17 combination of both methods was evaluated on the quality of vacuum packaged potato strips stored at 3±1 ˚C 18 for up to 10 days. For this study two cultivars of potatoes were assessed. For blanched Agata samples, the 19 lightness (L*) decreased over 12 % (p < 0.05). Moreover, their hue increased up to 100, obtaining lesser yellow 20 potato strips. In contrast, US did not affect the hue values. The losses of firmness of blanched potato strips were 21 notable (35 % for Agata and 51 % for Agria), whereas US did not change this property (p < 0.05). Nevertheless, 22 no significant differences were found in the total starch content at 10 days. Agata and Agria showed different 23 metabolic behavior of sucrose in the refrigerated storage. Therefore Agria cultivar retained better colour after 24 frying. These results suggest that US had less impact in colour and improve the firmness in vacuum-packaged 25 potato strips with no added chemicals. 26 27 28 29 Keywor ds: Colour, firmness, starch content, reducing sugars, vacuum packaging 30