Abstract: The present invention relates to a method of producing a composition of Gram-negative bacteria, the method comprising (a) subjecting a wet mass of Gram-negative bacteria to spray drying; and (b) contacting the spray-dried Gram-negative bacteria from step (a) to a compound, wherein the compound has a general formula (I) of, R1O—[(C2H3R2)—O]n—H??Formula (I) where R1 is a monovalent aliphatic radical having 1 to 22, preferably 2 to 10, especially 3 to 4, carbon atoms; R2 is in each case independently a hydrogen radical or a methyl radical; and n is a number from 1 to 300, preferably from 5 to 100, especially from 10 to 30, with the proviso that at least one R2 radical is a methyl radical.

Abstract: A method of producing a composition of Gram-negative bacteria includes (a) subjecting a wet mass of Gram-negative bacteria to spray drying; and (b) contacting the spray-dried Gram-negative bacteria from step (a) to a mixture including at least one hydrophobic, partially water-insoluble polyglycerol ester in combination with at least one emulsifier to form the composition of Gram-negative bacteria, wherein the polyglycerol ester has a general formula (I) of, MaDbTc??Formula (I) wherein, M=[C3H5(OR)2O1/2], D=[C3H5(OR)1O2/2], T=[C3H5O3/2], a=1 to 10; b=0 to 10; c=0 to 3; wherein, the sum total of a+b+c is 1 to 20, wherein the radicals R are independently selected from acyl radicals R?—C(=0)- and H, with the proviso that at least one radical R is not equal to H; wherein the radicals R? are independently selected from monovalent aliphatic, saturated or unsaturated hydrocarbon radicals with 3 to 39 carbon atoms.