Powdered plant beverages obtained by spray-drying without carrier addition-physicochemical and chemometric studies

Plant-based beverages (PBs) are currently gaining interest among consumers who are seeking alternative sustainable options to traditional dairy drinks. The study aimed to obtain powdered plant beverages without the addition of carriers by spray drying method to implement them in the future as an alternative to the liquid form of dairy drinks. Some of the most well-known commercial beverages sources like soy, almond, rice and oat were analyzed in this work. The effect of different treatments (concentration, addition of oat fiber) and two approaches od spray drying (conventional high temperature spray drying-SD, and dehumidified air spray drying at low temperature-DASD) were presented. Moreover, moisture content, water activity, particle morphology and size of obtained powders were analyzed. It was possible to obtain PBs without the addition of carriers, although the drying yield of four basic beverages was low (16.1-37.4%). The treatments and change in spray drying approach enhanced the drying yield, especially for the concentrated beverage dried using DASD (59.2%). Additionally, Fourier Transform Infrared (FTIR) spectroscopy was applied to evaluate the differences in chemical composition of powdered PBs. FTIR analysis revealed differences in the range of the absorption frequency of amide I, amide II (1700-1500 cm^-1) and carbohydrate region (1200-900 cm^-1). Principal component analysis (PCA) was carried out to study the relationship between spray dried plant beverages samples based on the fingerprint region of FTIR spectra, as well as the physical characteristics. Additionally, hierarchical cluster analysis (HCA) was employed to explore the clustering of the powders.