Abstract:

The aim of this study was to develop a maca processing system and provide a reliable method for preparing raw
materials for high-value maca products. For the preparation of maca fine powder, maca tubers were extracted with alcohol,
and the extract was then concentrated by evaporating the ethanol before spray drying. Three operating parameters, viz., feed
concentration, air inlet temperature and airflow rate were investigated. The best spray drying conditions were established by
single-factor and orthogonal array design methods as feed concentration 5%, air inlet temperature 120 ℃ and airflow rate
0.4 m3/min. Under the optimized conditions, the contents of moisture, alkaloid, protein, vitamin C and total sugar of
maca fine powder were 2.12%, 15.87 mg/g, 1.64 mg/g, 6.03 mg/g and 554.50 mg/g, respectively. The ultrastructure and
hygroscopic properties of the maca fine powder showed that the active components of maca were preserved by the optimized
spry-drying process and the final product could be used as an excellent raw materialfor the development of maca products.

Key words: maca, fine powder, spray drying