Impact du prétraitement au sel (NaCl) et du séchage sur les caractéristiques nutritionnelles et microbiologiques de l’oignon bulbe

Abstract

<jats:p>La culture de l’oignon contribue fortement à la sécurité alimentaire et à la lutte contre la pauvreté au Burkina Faso. Cependant, plusieurs contraintes dont les pertes post-récoltes entravent le développement de cette filière. L’objectif de cette étude était d’évaluer l’impact d’un procédé de séchage sur la qualité de l’oignon. L’oignon après parage, a été prétraité (NaCl à 5%) ou non, puis séché avec un séchoir à gaz Atesta (60-65 °C, 10-12 h). Les caractéristiques nutritionnelles et microbiologiques des produits frais et séchés ont été déterminées par des méthodes standardisées. Sur la base de la matière sèche, les résultats ont donné pour l’oignon frais, 5,19%, 1,7%, 12,16% et 47,56%, respectivement pour les cendres, matières grasses, protéines et sucres totaux. Après séchage, les teneurs ont varié respectivement de 2,96 à 31,31%, de 0,59 à 0,77%, de 3,58 à 7,78% et de 36,88 à 49,56% pour les cendres, matières grasses, protéines et sucres totaux. Malgré l’effet du prétraitement et du séchage, les teneurs en fer, manganèse, magnésium, zinc et calcium sont restées intéressantes. Les oignons séchés, en l’occurrence ceux prétraités avec le sel étaient de bonne qualité microbiologique. La vulgarisation de cette technologie permettra une meilleure valorisation de l’oignon au Burkina Faso.Mots clés : Séchoir à gaz, procédé, qualité, Burkina Faso.&#x0D; &#x0D; English Title: Impact of pretreatment with salt (NaCl) and drying on the nutritional and microbiological characteristics of onion bulb&#x0D; The production of onion greatly contributes to food security and the fight against poverty in Burkina Faso. However, several constraints including post-harvest losses hinder the development of this sector. The objective of this study was to assess the impact of drying process on the quality of onion. Onion after trimming, was pretreated (NaCl at 5%) or not and dried with a gas dryer Atesta (60-65 °C, 10-12h). Nutritional and microbiological characteristics of fresh and dried products were determined using standard methods. Based on the dry mater, results showed that fresh onion contains 5.19% of ash, 1.7% of fat, 12.16% of proteins and 47.56% of total sugars. After drying, ash, fat, proteins and total sugars content varied from 2.96 to 31.31%, 0.59 to 0.77%, 3.58 to 7.78% and 36.88 to 49.56%, respectively. Despite the effect of pretreatment and drying process, the content of iron, manganese, magnesium, calcium and zinc remained interesting. The dried onions, in particular those pretreated with salt presented good microbiological quality. The dissemination of onion drying technology will allow to add value to onion in Burkina Faso.Keywords: Gas-drier, process, quality, Burkina Faso.&#x0D; </jats:p>

The paradox of plant preference: The malaria vectors Anopheles gambiae and Anopheles coluzzii select suboptimal food sources for their survival and reproduction

“…Total sugar content was determined according to the sulfuric orcinol colorimetric method (Compaore et al., 2020 ). In the presence of concentrated sulfuric acid and at high temperatures, the hexoses and pentoses of the medium undergo a thorough internal dehydration, followed by a cyclization leading to the formation of furfural and 5‐hydroxymethylfurfural derivatives, reacting with orcinol to give a yellow–red complex.…”

“…The total sugar content of each species was expressed in D-glucose equivalent as g/100 g fresh material (Compaore et al, 2020).…”

The paradox of plant preference: the malaria vectorsAnopheles gambiaeandAnopheles coluzziiselect suboptimal food sources for their survival and reproduction

“…Total sugar content was determined according to the sulfuric orcinol colorimetric method 45 . In the presence of concentrated sulfuric acid and at high temperature, the hexoses and pentoses of the medium undergo a thorough internal dehydration, followed by a cyclization leading to the formation of furfural and 5-hydroxymethylfurfural derivatives, reacting with orcinol to give a yellow-red complex.…”

“…Sugar concentrations were determined using a standard curve, with D-glucose as the reference sugar. The total sugar content of each species was expressed in D-glucose equivalent as g/100 g fresh material 45 .…”

The paradox of plant preference: the malaria vectors Anopheles gambiae and Anopheles coluzzii select suboptimal food sources for their survival and reproduction

“…For each plant species, three measurements were made, each on different dates, and using different plant individuals. Total sugar content was determined according to the sulfuric orcinol colorimetric method 45 . In the presence of concentrated sulfuric acid and at high temperature, the hexoses and pentoses of the medium undergo a thorough internal dehydration, followed by a cyclization leading to the formation of furfural and 5-hydroxymethylfurfural derivatives, reacting with orcinol to give a yellow-red complex.…”