Aqueous, liquid surfactant mixture (A) comprises: fatty acids and their alkali metal or ammonium salts (a)； fatty acid ester compound (b)； fatty alcohol compounds (c)； fatty alcohol ether compounds (d)； fatty acid amide compounds (e)； fatty acid imine compounds (f), preferably amphoacetate； and/or primary, secondary, tertiary or quaternary fatty amine and/or fatty ammonium salts (g). Aqueous, liquid surfactant mixture (A) comprises: fatty acids and their alkali metal or ammonium salts (a) of formula (R(O)OH) or (R(O)OM)； fatty acid ester compound of formula (R(O)OR1a) (b)； fatty alcohol compounds of formula (ROH) (c)； fatty alcohol ether compounds of formula (ROR1a) (d)； fatty acid amide compounds of formula (R(O)NR1a) (e)； fatty acid imine compounds of formula (R(NR1a)NR2aR3a) (f), preferably amphoacetate； and/or primary, secondary, tertiary or quaternary fatty amine and/or fatty ammonium salts (g) of formula (RNH 2), (RHNR1a), (RNR1aR2a) or ((R)(R1a)(R2a)(R3a)N +>；X ->；). M : alkali metal cation or ammonium； R1a-R3a : organic or inorganic hydrophilic group； X ->；anion； and R (lipophilic part of the surfactant) : linear, optionally saturated, branched or unbranched 8-24C-alkyl, where the surfactant contains greater than 60, preferably 80-100 wt.% of = 18C-alkyl and 50-100, preferably 70-90 wt.% of one or more unsaturated alkyl, preferably the surfactant contains less than 20, preferably 15 wt.% of = 16C-alkyl and less than 5 wt.% of = 14C-alkyl.
