Effect of processing methods on the nutritional content of three traditional vegetables leaves: Amaranth, black nightshade and jute mallow

Abstract

The study assessed changes in nutritional content of some commonly consumed traditional vegetables subjected to postharvest processes. Amaranth (Amaranthus cruentus L.), black nightshade (Solanum scabrum Mill.) and jute mallow (Corchorus olitorius L.) leaves used as vegetables were subjected to blanching, boiling and drying. The proximate composition and β‐carotene content of fresh and processed leaves were determined. Amaranth, black nightshade and jute mallow leaves had 25.21%, 39.74% and 29.18% of protein, respectively. The β‐carotene levels were 16.40, 25.25 and 27.74 mg/100 g for black nightshade amaranth and jute mallow leaves, respectively. The ash content was 10.57% for black nightshade, 12.40% for jute mallow and 16.33% for amaranth. Processing methods caused decreases of β‐carotene and crude lipid content. Boiling for 30 min or more resulted in large loss of β‐carotene. Drying under shade resulted in less loss of β‐carotene than drying in cabinet at 50 and 60°C.

Effect of Blanching and Drying Temperatures on Various Physico-chemical Characteristics of Green Beans

“…Blanched dried samples showed significantly (p≤0.05) more carbohydrate content than un-blanched dried samples which might be attributed to the breakdown of ketogenic amino acids to glucose during blanching thereby increasing the carbohydrate content of dried green bean samples (Fadupin et al 2014). Similar trend was also reported by Traore et al (2017) in dehydrated amaranth leaves. Also there was a significant (p ≤ 0.05) increase in carbohydrate content with increase in drying temperature.…”

Effect of Boiling and Wet Frying on Nutritional and Antinutrients Content of Traditional Vegetables Commonly Consumed in Malawi

“…Thus most minerals were leached into the boiling water and this led to reduced ash content because the ash contains minerals. These results tally with the work done by Traoré , K., Parkouda, C., Savadogo, A., Ba, F., Regine, H., & Yves, K., (2017) where it was found that the amount of ash reduced after blanching and boiling of vegetables that included jute mallow and Amaranth cruentus L. The authors found that the amount of ash reduced in jute mallow and Amaranth from 12.40% and 16.33% to 9.37% and 14.27% respectively after boiling for 30 minutes due to leaching of minerals in the boiling water.…”

“…Beta-carotene losses due to frying has been attributed to loss of the initial carotenoids concentration because of leaching into oil at higher processing temperature. Traoré et al, 2017 also reported a reduction of beta-carotene in jute mallow and amaranth due to shade drying alone. The results for shade dried samples of jute mallow and amaranth in this study agrees with those reported by Traoré et al, 2017.…”

“…Traoré et al, 2017 also reported a reduction of beta-carotene in jute mallow and amaranth due to shade drying alone. The results for shade dried samples of jute mallow and amaranth in this study agrees with those reported by Traoré et al, 2017. Results from the study by Putra, U.…”

Le kawal, un condiment a base de feuilles fermentees de senna obtusifolia: technologies et valeurs nutritionnelles

“…Les légumes-feuilles améliorent la qualité nutritionnelle des régimes alimentaires en raison de leur composition biochimique et leurs propriétés fonctionnelles [2,3]. Ils constituent une importante source de protéines, de vitamines, de fibres et de minéraux [4,5]. La plupart de ces légumes sont des espèces sauvages des forêts et utilisées par les communautés locales vivant dans différentes zones agroécologiques [6].…”