A method of producing a treated mixture that is free of acrolein or that has a lower concentration of acrolein than a comparative untreated mixture, the method comprising contacting a starting mixture comprising constituent at least one compound that is not acrolein and constituent an acrolein-forming precursor composition, with an effective amount of a monoamine of formula (I-1) R 1a R 2a R 3a N (I-1) so as to produce a treated mixture comprising constituent at least one compound that is not acrolein, wherein the treated mixture is free of acrolein or has a concentration of acrolein that is from > 0 percent to less than 50 percent of a first concentration of acrolein in the comparative untreated mixture when both of the treated and untreated mixtures are tested according to Acrolein Test Method 1 as disclosed in the description; wherein constituent of the treated mixture is a product of a reaction of the constituent of the starting mixture; and wherein: R 1a is a monovalent (C 1 -C 20)aliphatic group, a monovalent (C 1 -C 20) oxaaliphatic group, a monovalent (C 6 -C 14)aryl group, or a monovalent (C 2 -C 12)heteroaryl group; and each of R 2a and R 3a is independently H, a monovalent (C 1 -C 20)aliphatic group, or a monovalent (C 1 -C 20)oxaaliphatic group; or R 1a and R 2a are bonded together to give a divalent group of formula -R 1b -R 2b -, wherein the divalent group is a divalent (C 2 -C 20)aliphatic group, or a divalent (C 1 -C 20)oxaaliphatic group and R 3a is H, a monovalent (C 1 -C 20)aliphatic group, or a monovalent (C 1 -C 20)oxaaliphatic group; or R 1 and R 2 and R 3 are bonded together to give a trivalent group of formula -R 1a -R 2a -R 3a -, wherein the trivalent group is a trivalent (C 3 -C 20)aliphatic group, or a trivalent (C 2 -C 20)heteroaliphatic group; wherein each aliphatic group, oxaaliphatic group, aryl group, and heteroaryl group is independently unsubstituted or substituted with 1 to 5 substituents independently selected from a halogen atom, oxo (i.e., =O), -OR, wherein each R is independently H, an unsubstituted (C 1 -C 20)hydrocarbyl group or an unsubstituted (C 1 -C 20)oxahydrocarbyl group; and wherein each oxaaliphatic group and oxyhydrocarbyl group, independently contains from 1 to 4 oxygen atoms; with the proviso that the amine of formula is free of -SH; a silicon atom; a 1,2-dihydroquinolinyl; a nitrogen bonded to an atom selected from N, O, and S; and a nitrogen bonded to a group selected from allyl, a carbamoyl group, and an oxymethylene group; wherein the constituent acrolein-forming precursor composition comprises an organic peroxide and a compound containing an oxygen-bonded allyl group or nitrogen-bonded allyl group. R 1a is a monovalent (C 1 -C 20)aliphatic group, a monovalent (C 1 -C 20) oxaaliphatic group, a monovalent (C 6 -C 14)aryl group, or a monovalent (C 2 -C 12)heteroaryl group; and each of R 2a and R 3a is independently H, a monovalent (C 1 -C 20)aliphatic group, or a monovalent (C 1 -C 20)oxaaliphatic group; or R 1a and R 2a are bonded together to give a divalent group of formula -R 1b -R 2b -, wherein the divalent group is a divalent (C 2 -C 20)aliphatic group, or a divalent (C 1 -C 20)oxaaliphatic group and R 3a is H, a monovalent (C 1 -C 20)aliphatic group, or a monovalent (C 1 -C 20)oxaaliphatic group; or R 1 and R 2 and R 3 are bonded together to give a trivalent group of formula -R 1a -R 2a -R 3a -, wherein the trivalent group is a trivalent (C 3 -C 20)aliphatic group, or a trivalent (C 2 -C 20)heteroaliphatic group; wherein each aliphatic group, oxaaliphatic group, aryl group, and heteroaryl group is independently unsubstituted or substituted with 1 to 5 substituents independently selected from a halogen atom, oxo (i.e., =O), -OR, wherein each R is independently H, an unsubstituted (C 1 -C 20)hydrocarbyl group or an unsubstituted (C 1 -C 20)oxahydrocarbyl group; and wherein each oxaaliphatic group and oxyhydrocarbyl group, independently contains from 1 to 4 oxygen atoms; with the proviso that the amine of formula is free of -SH; a silicon atom; a 1,2-dihydroquinolinyl; a nitrogen bonded to an atom selected from N, O, and S; and a nitrogen bonded to a group selected from allyl, a carbamoyl group, and an oxymethylene group; wherein the constituent acrolein-forming precursor composition comprises an organic peroxide and a compound containing an oxygen-bonded allyl group or nitrogen-bonded allyl group.