Microstructure and flow properties of lyophilized mango pulp with maltodextrin

Abstract

The present study had as objective to determine the flow properties and behavior of lyophilized mango pulp powder as a function of different concentrations of maltodextrin. In the samples of the powders contain 5, 10 and 15% of maltodextrin the angle of effective internal friction, wall friction angle, flow index and bulk density were determined. The microstructure was evaluated by scanning electron microscopy. The freeze-dried samples are characterized as having an amorphous structure, and the drying aid used modified the surface of the particles. The flow index was 3.19, 4.28 and 4.53 for samples containing, respectively, 5, 10 and 15% maltodextrin. Increasing the concentration of maltodextrin in the mango pulp decreased the effective angles of internal friction and wall friction. The bulk density of the powders increased with increasing concentration of maltodextrin for the samples containing 5, 10 and 15% of the maltodextrin, being equal to 597.8, 689.8 and 691.3 kg m-3, respectively. Thus, it was concluded that the addition of maltodextrin modified the shape of the particles, decreased segregation, affected the flow properties of the mango powders, facilitating flow and increasing their bulk density.

Flow behavior of cocoa pulp powder containing maltodextrin

“…Mohammed et al (2011) state that irregularities on the particles' surfaces cause an interconnection between them, increasing the resistance to flow. Afonso et al (2019) observed the same behavior in mango pulp powders, in which the highest values of FI (4.29 and 4.52) were found in those with higher concentrations of maltodextrin, 10 and 15%, respectively.…”

“…The addition of maltodextrin to the pulp directly interfered with the wall friction angle, and it decreased with the increase in the concentration of this adjuvant for both drying processes (Table 2). Afonso et al (2019) observed the same behavior in mango pulp powders containing maltodextrin. The friction between the powder and a wall is related to the resistance to flow existing between the powder particles and the wall material.…”

“…On the other hand, the addition of maltodextrin to cocoa pulp produced powders with smoother surfaces. This behavior was verified by Afonso et al (2019) in freeze dried mango pulp powder. According to Tonon et al (2009), smoother surfaces can improve the flow characteristics of the material.…”

“…Higher values of wall friction result in higher loads transferred to the silo wall surfaces, necessary to ensure a mass flow in the funnel (Iqbal & Fitzpatrick, 2006). Therefore, the lower the value of this angle, the lower the slope needed by a wall to ensure the powders' flow (Afonso et al, 2019).…”

Flowability of spray‐dried sapodilla pulp powder

“…Maciel et al (2020) classified as cohesive and easy flowing the cupuaçu pulp powders containing maltodextrin, with I f values ranging from 3.25 to 4.09. Similarly, Afonso et al (2019), in their study with mango pulp powder containing maltodextrin, classified it as easy-flowing, with I f values between 3.19 and 4.52 I f .…”