Shelf life assessment and antioxidant degradation kinetics of a pineapple–ginger agglomerated powder: Insights into storage stability

Agglomerated food powders may undergo degradation reactions during storage, resulting in the loss of nutritional quality and functional properties. This research aimed to evaluate the stability of an agglomerated pineapple–ginger powder mixture (APGPM), obtained through the fluidised bed process. The mixture was stored at different temperatures (T) (15, 25 and 35°C) over different periods (t) (0, 30, 60, 90, 120, 150 and 180 days). The samples were stored in a controlled environment at 65% relative humidity, packed in PET foil-laminated film bags. Moisture (Xw), water activity (aw), Carr’s index (CI), Hausner’s ratio (HR), solubility, hygroscopicity, wetta-bility, color (L, a*, b*), antioxidant capacities (ABTS and DPPH), total phenols (TP), total flavonoids (TF), vitamin C (Vit. C) and β-carotene (β-car) were monitored. Overall, ANOVA showed statistically significant differences (P < 0.05) in most of the dependent variables concerning t, T, and their interaction (t-T). At the end of storage, moisture and aw showed values conferring stability to APGPM. Fluidity was classified as good and very good, and cohesiveness as low. Colour was stable, with no significant differences observed. The lowest retention values were found for ABTS (33.6–50.7%), DPPH (34.0–61.2%), TP (64.8–70.8%), TF (30.1–0.53%), Vit. C (12.8–40.0%) and β-car (0–39%).