Effect of sieved fractionation on the physical, flow and hydration properties of Boscia senegalensis Lam., Dichostachys glomerata Forssk. and Hibiscus sabdariffa L. powders

Abstract

This study aimed at evaluating the effect of successive grinding and sieving processes on the physicochemical properties of powders obtained from Boscia senegalensis seeds, Dichostachys glomerata fruits and Hibiscus sabdariffa calyxes. Plant powders were fractionated into four granulometric classes and their properties were compared to those of unsieved powders. Mean particle size exerted a significant influence (p \ 0.05) on the plant powders properties. The smaller the particle size of the powder fraction, the higher the protein, lipid and ash contents and the lower the carbohydrate and fiber contents. The decrease in particle size increased particle sphericity and elongation and enhanced flowability of B. senegalensis and D. glomerata powders, whereas an inverse tendency seemed to be observed for H. sabdariffa powders. Water absorption capacity, water solubility index and dispersibility were improved for finer particles for all plants. Sieve fractionation is a novel approach for improving physicochemical properties of plant powders.

Enhancing the quality of overripe plantain powder by adding superfine fractions of Adansonia digitata L. pulp and Hibiscus sabdariffa L. calyces: characterization and antioxidant activity assessment

“…In fact, the inter-particle voids decrease by adding the finer powder, this would offer a larger contact surface with the surroundings, leading to a more compact structure and this would result in a decrease in porosity. The same trend was reported by Zhao et al [46] and Deli et al [47] respectively on red grape pomace and three tropical plants powders. According to Hu et al [48], the quality of powder in food industry could be controlled by porosity (which depends on bulk and true densities), and have been fundamentally exploited.…”

Effect of milling and sieving processes on the physicochemical properties of okra seed powders

“…Although extensive information is available about nutritional quality of okra seeds, no study, to our knowledge, focused on the distribution of nutritional compounds within granulometric classes of okra seed powders produced by milling processes. In fact, it can be hypothesised that large particles may be richer in fibres, which are difficult to grind; hence, small particles may be enriched in minerals, fat and proteins and have a higher nutritional quality, as previously reported for various plant parts (Becker et al , ; Zaiter et al , ; Deli et al , ). For this purpose, the current study deals with the production of okra seed powders by successive milling and sieving processes, with the aim to determine whether some granulometric classes of okra seeds powder could have a great nutritional quality (Adelakun & Oyelade, ; Chen et al , ), making them suitable for the production of food supplements.…”

“…As fibres were included in total carbohydrates in the proximate composition analysis, the larger content in carbohydrates of higher size granulometric classes of okra seed powders may be due to a higher proportion of fibres. Bioactive compounds are often associated with proteic and fatty fractions; thus, the smaller granulometric classes of okra seeds are expected to have higher contents in bioactive compounds (Becker, et al , ; Deli, et al , ). At higher milling speed, this differential distribution of macronutrients within granulometric classes was enhanced: small particles contained even more proteins and fat and less moisture, carbohydrates and ashes.…”

Phytochemical Profile and <i>In Vitro</i> Antioxidant Properties of Essential Oils from Powder Fractions of <i>Eucalyptus camaldulensis</i> Leaves

“…The fact that the major volume of E. camaldulensis powder corresponded to large particles can be explained by the expected non-sphericity of large particles, as ground fibers generally lead to large rod-shaped particles. So, fine particles can stick to larger particles and thus be retained by sieves of mesh size exceeding their diameter [27]. As the median distribution of the mother powder being located around 200 μm, the fractionation sieves were chosen as follows: a 200 μm sieve for studying the particles around the median; a 100 µm sieve for studying particles below the median and a 355 µm sieve for studying particles above the median.…”