New Artichoke Flours with High Content of Bioactive Compounds

Artichoke by-products are rich in bioactive compounds and could be valorized for use as flour. Blanching is a critical pretreatment in the production of flour from artichokes, as it helps preserve bioactive and nutritional compounds before cutting, drying and milling. However, studies on the blanching of artichoke by-products for flour production are scarce in contrast to those studies on edible artichoke parts. In this article, the effect of different blanching treatments (steam or immersion; 3–15 min) on the bioactive compounds (total phenolic content, TPC; total antioxidant capacity, TAC; and inulin) and color quality of flours of artichoke by-products (obtained after cutting, drying and milling of stems and bracts) was studied. Blanching treatments induced increases in TPC, TAC and inulin, although those increments varied greatly depending on the treatment type and artichoke part. In particular, steaming (15 min) induced the highest TPC increment in artichoke hearts and stems (94 and 46%, respectively); TAC increment in hearts, stems and bracts (987, 1107 and 1660%, respectively); and inulin increment in hearts and stems (106 and 14%, respectively). Steaming (3 min) induced the highest inulin increment in bracts (40%). Immersion (15 min) induced the highest TPC increment in bracts (632%). In addition, the short blanching treatment (3 min) was not enough to inactivate browning enzymes with browning index values of 75, 52 and 67, which were similar, or even higher, to control samples (unblanched). In conclusion, steam blanching for 15 and 3 min induced the highest bioactive contents in stems and hearts and inulin and TAC contents in bracts.