| Abstract
| - A method for microbial isomerization of oat linoleic acid to conjugated linoleic acid (CLA) wasdeveloped. The method includes hydrolysis of oat lipids in aqueous flour slurries by the endogenousoat lipase. Then, the flour slurry containing free linoleic acid is utilized as a substrate for theisomerization reaction carried out by resting cells of Propionibacterium freudenreichii ssp. shermanii.The isomerization reaction progressed most effectively when, after the lipid hydrolysis period, thepH of the slightly acidic oat slurry was elevated to 8.0−8.5 and maintained at this range. With slurriescontaining 5% (w/v) oat flour, the amounts of CLA formed per dry matter were up to 10.1 mg/gcorresponding to 102 mg/g lipids or 0.44 mg/mL slurry. Increments in the flour content up to 15%increased the volumetric production of CLA to 0.85 mg/mL. The proportion of the cis-9,trans-11 isomerwas 80% of the total CLA formed. CLA could be concentrated into the solid material of the oat slurryby acidification. Keywords: Conjugated linoleic acid; Avena sativa; Propionibacterium freudenreichii; linoleic acid
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