An individual alkamide and/or a mixture having two or more different alkamides, is disclosed for changing, masking or reducing the unpleasant flavor impression of an unpleasant-tasting substance or mixture of substances. The alkamide can be trans-pellitorine; cis-pellitorine; 2Z,4Z- or 2Z,4E-decadienoic acid-N-isobutylamide; 2E,4E-decadienoic acid-N-([2S]-2-methylbutyl)amide; 2E,4E-decadienoic acid-N-([2R]-2-methylbutylamide); 2E,4Z-decadienoic acid-N-(2-methylbutyl)amide; achilleamide; sarmentine; 2E- or 3E-decenoic acid-N-isobutylamide; 3E-nonenoic acid-N-isobutylamide; spilanthol; homospilanthol; 2E,6Z,8E-decatrienoic acid-N-([2R]-2-methylbutyl)amide; 2E- or 2Z-decen-4-oic acid-N-isobutylamide; .alpha.-sanshool; .alpha.-hydroxysanshool; .gamma.-hydroxysanshool; .gamma.-hydroxysanshool; .gamma.-hydroxyisosanshool; .gamma.-dehydrosanshool; .gamma.-sanshool; bungeanool; isobungeanool; dihydrobungeanool; or tetrahydrobungeanool, or combinations thereof.