The present invention relates to a method of removing off-flavour from a soy protein containing substrate, said method comprising a neutralisation procedure which includes the following steps: - providing a pasteurised or sterilised aqueous liquid containing 0.5-8 wt.% of dissolved soy protein； - inoculating the pasteurised or sterilised liquid with a culture containing an off-flavour removing lactic acid bacteria (LAB) strain capable of metabolising a C 5-C 9n- alkanal and/or trans-2-hexenal, said inoculation optionally occurring after said pasteurised or sterilised liquid has first been fermented with another micro-organism； - fermenting the inoculated aqueous liquid by incubation at a temperature in the range of 20-45 ºC for 0.4-6 hours； wherein less than 600 ppm of lactate is formed during said neutralisation procedure. The present method enables removal of typical soy-related off- notes in a very effective way by employing a LAB strain capable of metabolising a C 5-C 9n-alkanal and/or trans-2-hexenal and by conducting a relatively short fermentation that yields not more than limited quantities of lactate.
