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 (ρ b), compacted density (ρ c), 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%).