Optimization of spray-drying process parameters on strawberry (Fragaria ananassa D.) extracts microcapsules quality

BACKGROUND: The strawberry is a fruit with great acceptance by the consumer due to its pleasant flavor and functionality; It is rich in vitamin C, tannins, flavonoids, anthocyanins, catechin, quercetin and kaempferol, organic acids and minerals. OBJETIVE: The objective of the research was to evaluate the effect of the feed formulation and the spray-drying process on the quality of strawberry extract microcapsules (EMs). METHODS: The response surface methodology was used with a central composite design centered on the face (α= 1), considering the factors: maltodextrin (MD), inlet air temperature (IAT), outlet air temperature (OAT) and atomizing disk speed (ADS), and the response variables: humidity (Xw), water activity (aw), solubility (S), wettability (We), hygroscopicity (Hy), bulk density (ρb), compacted density (ρc), total phenols (TP), antioxidant capacity, angle of repose (AR), strawberry powder particle size (D[3 ;2]), color (CIE-Lab), and process yield (Y). RESULTS: The aw and Xw values guarantee microbiological stability and control over degradation reactions in EMs. For the levels evaluated, the S was affected by OAT and ADS, and interaction IAT*MD, ADS*MD, IAT2, and MD2. The We depended on the factors IAT, OAT, and the interactions IAT*OAT and IAT*MD. ABTS activity was affected by the factors ADS, ADS*MD and IAT2. The Y was affected by OAT, MD, IAT*OAT, IOT*ADS, IOT*MD, OAT*ADS, ADS*MD, IOT2, and OAT2. The increase in MD caused a decrease in Hy. The value of L* was affected by ADS and MD, effects due to temperature did not affect the levels evaluated, and chromaticity a* was positively affected by the increase in ADS. IAT and MD presented a statistical effect on AR. CONCLUSIONS: The experimental optimization reached a desirability of 73.7%, being the optimal conditions: IAT (154°C), OAT (89°C), ADS (16,805 rpm), and MD (11.5%).