Stability of a colloidal system based on avocado (Persea americana Mill. cv. Hass) and others: Effect of process and composition

Abstract

Avocado (Persea americana Mill. cv. Hass), is a perishable fruit, which compositionally presents nutritional benefits, which has led to its productive chain to look for new alternatives of agroindustrialization to improve its competitiveness in the market, being guacamole a potential option. The aim of this research was to evaluate the influence of composition and homogenization process on the colloidal system stability based on avocado and other ingredients for a potential use in the aspersion drying process. We used the surface response methodology and a central composite experimental design for experimental optimization of the process, considering three independent variables as follows: avocado dry solids (DSavocado), homogenization time and tert-butylhydroquinone concentration (TBHQ), and six dependent variables: zeta potential (-ζ), color (L *: brightness, a *: green-red chromaticity, b *: yellow-blue chromaticity), viscosity (μ), spectral absorption stability index, peroxide index (PI) and particle size (D10, D50 and D90). The best emulsion and process formulation was achieved with 47.1% of DSavocado, 5 min of homogenization and 100 mg.kg-1 of TBHQ, obtaining an emulsion with -ζ = -27.67 ± 0.29, L * = 51.3 ± 1.0, a * = -5.8 ± 0.8 and b * = 30.0 ± 1.9, μ = 1034.56 ± 95.91 cP , R = 0.78 ± 0.03, IP = 0.73 ± 0.30 meq H2O2.Kg-1 emulsion, D10 = 8.1 ± 0.7 μm, D50 = 56.2 ± 11.5 μm and D90 = 346.6 ± 94.6 μm. The emulsion based on avocado and other ingredients, presents a physico-chemical, physical stability adequate stability, which guarantees a potential use for aspersion-drying process, since it meets with the criteria design for viscosity and total solids, of the pilot unit PSALAB, Vibrasec S.A.

Spray-drying of fruit and vegetable juices: Effect of drying conditions on the product yield and physical properties

“…Some researchers have reported that when a colloidal system presents a II> 25 mV, there is a strong electrostatic repulsion of the particles, which gives it an adequate physicochemical stability [18], [27], [29] Similar values have been reported for stable guacamole emulsions (II = 27,7 ± 0,3 mV) [51]. Other research has reported superior values in coconut-based colloidal systems (II = 45,6 ± 2,5 mV) [52] and in yacon (Smallanthus sonchifolius) suspensions (II = 33.8±4,0 mV) [27]; however, Marin et al, [53] reported stable blackberry suspensions with probiotics and prebiotics with II = 13.3 ± 0.3 mV.…”

“…A consistent behavior was observed with respect to GA and t, increasing the one with the increase of GA and t; on the other hand, the t-GA interaction was positive, denoting the highest µ when the system operates at higher t (5 min) and higher GA (0.4%) (figure 2-1 b). On the other hand, it is considered that cell wall pectin has a synergistic effect with added GA, enhancing at higher t, where a higher release from the cell structure is favored and the values reached are comparatively high compared to banana suspensions (204 Pas) and similar to suspensions of yacon (Smallanthus sonchifolius) (1000 Pas) [27], and avocado emulsions (1034 Pas) [51].…”

Influence of gum arabic and homogenization process on the physicochemical stability of strawberry suspensions

“…A consistent behavior was observed with respect to GA and t, increasing µ with the increase of GA and t. However, the t-GA interaction was positive, denoting the highest µ when the system operates at higher t (5 min) and higher GA (0.4%). Furthermore, it is known that cell wall pectin has a synergistic effect with added GA, enhancing at higher t, where a higher release from the cell structure is favored, and the values reached are high compared to banana suspensions (204 Pa) and similar to suspensions of yacon (1000 Pa) (López et al, 2009) and avocado emulsions (1034 Pa) (Estrada Mesa et al, 2017).…”