L’évaluation des caractéristiques physicochimiques et organoleptiques sur l’oignon blanc d’Oulhaça menée en sec et en irriguée.

Abstract

The onion is a basic ingredient for several culinary preparations and is an important source of income for those involved in the sector. Our objective of the present study focused on the evaluation of the physicochemical characteristics and the sensory quality on the one hand and the determination, evaluation of the phenolic compounds on the other hand of the variety of white onion of oulhaça wilaya d 'AIN TEMOUCHANTE. Samples of fresh onion bulbs in dry and irrigated were collected from the region of oulhaça for the determination of total dry matter, ash, fat and total protein, onion in dry presented a content in dry matter of 13.98%, against 11.5% for the irrigated onion, on the basis of dry matter (DM) the contents of proteins, fats and ash were respectively of the order of 16, 37%, 2.9% and 3.18% for dry onion and around 17.03%, 5.21% and 3.44% for irrigated onion. The determination of total polyphenols and flavonoids of bulb extracts after maceration using ethanol as solvent were respectively carried out by the method using the reagent of folin- Ciocalteu and the method of aluminum trichloride (AlCl3). Indeed, the results obtained are respectively of the order of (27.6 ± 1.57 mg of EAG / 100g of Extract) and of (11.2 ± 0.80 mg of EQ / 100g of Extract ) for dry onion, and of the order of (19.6 ± 3.04 mg of EAG / 100g of Extract) and of (5.67 ± 0.99 mg of EQ / 100g of Extract) for irrigated onion. Regarding the organoleptic characteristics or the sensory qualities, the study concerned three samples of onions which were coded as follows: A15 (the fresh onion bulbs collected from the region of oulhaça), A25 (the bulbs fresh onion variety oulhaça collected from the High school of agronomy MOSTAGANEM), A35 (purple colored onion collected from the wilaya of MASCARA), the tasters found that samples A15 and A25 are white in color, with an external texture smooth, tender, odor (fresh, neutral and moderately intense), juicy and of good flavor, on the other hand A35 is purple in color, moderately smooth, harder, of intense odor, moderately juicy and of good flavor. Finally, the white onion variety of Ooulhaça deserves labeling thanks to its nutritional potential and excellent organoleptic characteristics and to a significant potential of its phenolic compounds. And also it is suitable for storage for a long time thanks to its high dry matter content (about 13.98%).