IDS’2018 – 21st International Drying Symposium València, Spain, 11-14 September 2018 DOI: http://dx.doi.org/10.4995/ids2018.2018.7876 21 ST INTERNATIONAL DRYING SYMPOSIUM EDITORIAL UNIVERSITAT POLITÈCNICA DE VALÈNCIA Valorization of the tomato to obtain a powder rich in antioxidant constituents Mennouche, D. a,b,* ; Boubekri, A. a,c ; Bouchekima, B. a,d ; Boughali, S. a,f ; Moumeni, R. a,b ; Boutadjine, D. a a Université Kasdi Merbah Ouargla, Laboratoire de Développement des Energies Nouvelles et Renouvelables dans les Zones Arides et Sahariennes Ouargla 30000, Algeria. b Département de Génie des Procédés, Université Kasdi Merbah Ouargla 30000, Algeria c Département des Energies Renouvelables, Université Kasdi Merbah Ouargla 30000, Algeria e Département de Génie Mécanique, Université Kasdi Merbah Ouargla 30000, Algeria. f Département de Physique, Université Kasdi Merbah Ouargla 30000, Algeria. *E-mail of the corresponding author: mennouche@gmail.com; mennouche.dj@univ-ouargla.dz Abstract The tomato (Lycopersicon esculentum), widely consumed fresh fruit but also in processed form, is recognized for its nutritional qualities, rich in micro components, such as carotenoids (lycopene in particular), phenolic compounds and vitamin C. The goal of this work is to valorize the tomato; in the form of paste, seeds, peel and mixture of seeds-peel; in order to obtain a powder rich in antioxidant constituents. Convective drying of the various tomato by-products (paste, seeds, peel and mixture) is an essential process in the valorization of the studies products. The results obtained, showed that our analysed samples are rich in phenolic compounds. The mixture seeds-peel has slightly higher total polyphenol content (190.65 mg EAG / ml), peel (157.36 mg EAG / ml), seeds (140.56 mg EAG / ml) and the paste (120 mg EAG / ml). The evolution of the color of dried by-products (method L, a, b), shows that the mixture (seeds-peel) has a better result of parameter "a" (indicates the red color and signifies the presence of Lycopene). Keywords: tomato, drying, antioxidant, polyphenols. 715