Pineapple pulp was homogenised at different pressures, and its stability investigated by way of flow curves, particle size distribution, morphology, cloudiness and sedimentation. The particle size of the homogenised pulp ranged from 400 to 100 lm for homogenisation pressures of between 0 and 700 bar. The pineapple pulp showed shear thinning behaviour with increasing flow index (n) after processing at higher pressures. In addition, the pulps with smaller particles showed less serum cloudiness, even though the sedimentation tests showed the highest stability for pulp homogenised between 200 and 300 bar. Above 400 bar, the pulp showed phase separation and higher sedimentation indexes, similar to that observed for the untreated samples, which was attributed to the formation of aggregates because of interparticle attraction.

Summary Coffee oil microcapsules were produced by spray‐drying using as encapsulating agents gum Arabic, whey protein isolate (WPI) and mixtures of maltodextrin (MD) and WPI, at three different proportions (3:1, 1:1 and 1:3). Sorption isotherms were determined by the gravimetric method, and the glass transition temperature (Tg) was measured by differential scanning calorimetry. Microcapsules produced with gum Arabic showed the highest water adsorption and underwent a stronger water plasticising effect. At the highest water activity (0.843), this sample had a Tg value of −18.3 °C, while those produced with WPI at higher proportions showed values around 25 and 30 °C. The good fit of experimental data by Guggenheim‐Anderson‐de Boer and Gordon–Taylor models allowed the determination of the critical storage conditions, at which powders are not susceptible to deteriorative physical changes. The samples produced with 1:1 and 1:3 of MD/WPI were the most stable ones, showing critical water activity values of 0.890 and 0.938, respectively.

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99.9%). The experimental design responses evaluated were the technological properties of the fibers: water-holding, oil-holding, and swelling capacity. Since these properties were present in high levels, the lemon residues could be used to increase content of fibers in foods resulting in the addition of nutritional benefits for the consumers.]]>

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