Reduction in the biogenic amine content of raw milk Manchego cheese by using biogenic-amine-degrading lactic acid bacteria

The consumption of artisan cheeses, made with raw milk, is a widespread practice in southern European countries. These cheeses are highly appreciated for their unique sensory characteristics. An example of this type of cheese is artisanal Manchego cheese. Raw milk cheeses have a very complex microbiota, which is responsible for intense proteolysis that originates amino acids and often has high decarboxylase enzymatic activity, resulting in the production of biogenic amines (BAs). Ingestion of foods with high concentrations of BAs can cause adverse health effects, so it is important to control or reduce their production. A possible strategy for reducing BA accumulation in these cheeses is to use strains with BA-degrading capacity. For this purpose, the BA-degrading capacity of 37 strains of lactic acid bacteria (LAB) isolated from different food ecosystems was studied. The strains L. plantarum UCLM-93, L. acidophilus UCLM-104, and L. plantarum UCLM-77 were selected since they were capable of totally degrading all or almost all of the amines assayed, and they were used as a co-culture for the manufacture of artisanal raw milk Manchego cheese. The results obtained were promising, reaching percentages of reduction in the total amine content of up to 80%. The highest BA reduction percentages were obtained at 60 days of ripening, with values of 93.8% for tyramine, 78.7% for cadaverine, and 73.7% for histamine. At the same time, the inoculated cheeses presented the typical organoleptic characteristics of artisanal Manchego cheese.