Fermentation process
View Patent ↗A process for forming a color and odor stable polycarboxylic acid or polyhydroxy acid is provided. The process is carried out by fermenting a mixture containing a substrate which can be converted by fermentation into a polycarboxylic acid or a polyhydroxy acid, an organism capable of transforming the substrate by fermentation in a fermentation medium containing a source of carbon and energy, a source of inorganic nitrogen, a source of phosphate, a metal, a biotin which is substantially free of particulate matter and bacteria.
1. A process for making a color and odor stable polycarboxylic acid or a polyhydoxy acid comprising:
(a) providing an organism for producing a polycarboxylic acid or a polyhydroxy acid;
(b) providing a substrate for conversion to a polycarboxylic acid or a polyhydroxy acid by the organism;
(c) providing a fermentation medium consisting of:
(i) a source of metabolizable carbon and energy;
(ii) a source of inorganic nitrogen selected from the group consisting of ammonia, ammonium hydroxide, ammonium sulphate, and mixtures thereof;
(iii) potassium phosphate;
(iv) at least one metal selected from the group consisting of an alkali metal, an alkaline earth metal, a transition metal, and mixtures thereof;
(v) a source of biotin, substantially free of particulate matter and bacteria;
(vi) at least one chelating agent; and
(vii) an antifoam agent; and
(d) fermenting a mixture comprising said organism, substrate and fermentation medium of (a), (b) and
(c) at a pH 5.4 to 7.
2. The process of claim 1 , wherein, the organism is Candida tropicalis.
3. The process of claim 1 , wherein, the substrate is an alkane having from about 4 to about 25 carbon atoms.
4. The process of claim 1 , wherein, the source of carbon and energy comprises glucose.
5. The process of claim 1 , wherein the source of inorganic nitrogen is ammonium sulfate.
6. The process of claim 1 , wherein the metal is calcium.
7. The process of claim 1 , wherein metal is magnesium.
8. The process of claim 1 , wherein the metal is calcium and magnesium.
9. The process of claim 1 , which further comprises adding at least one trace metal during the fermentation.
10. The process of claim 1 , further comprising, maintaining dissolved oxygen concentration levels below about 25% during step (d).
11. The process of claim 1 , wherein the source of Inorganic nitrogen comprises a member selected from the group consisting of ammonia, ammonium hydroxide, and mixtures thereof.