title: Formation of complex natural flavours by biotransformation of apple pomace with basidiomycetes.
abstract: Altogether 30 different basidiomycetes were grown submerged in liquid culture media using seven different by-products of the food industry as the only carbon source. Seven fungus/substrate combinations revealed interesting flavour profiles. Culture supernatants of Tyromyces chioneus grown on apple pomace were extracted, and the aroma compounds were analysed by gas chromatography-olfactometry (GC-O). Potent odorants were identified by aroma extract dilution analysis (AEDA), calculation of the odour activity values (OAV), and proven by confection of an aroma model. 3-Phenylpropanal, 3-phenyl-1-propanol, and benzyl alcohol were identified as potent aroma biotransformation products. Headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) experiments showed that 3-phenylpropanal, 3-phenyl-1-propanol, benzyl alcohol, methyl 3-phenylpropionate, methyl 2-phenylacetate, cinnamaldehyde and methyl cinnamate were produced during the cultivation period of eight days. By means of labelling experiments, (E)-cinnamic acid was identified as the precursor of 3-phenylpropanal and 3-phenyl-1-propanol. Basidiomycetes were able to biotransform food by-products to pleasant complex flavour mixtures.
authors.affiliation: Justus Liebig University Giessen, Institute of Food Chemistry and Food Biotechnology, Heinrich-Buff-Ring 58, 35392 Giessen, Germany.
authors.forename: Andrea K
authors.initials: AK
authors.lastname: Bosse
authors.forename: Marco A
authors.initials: MA
authors.lastname: Fraatz
authors.forename: Holger
authors.initials: H
authors.lastname: Zorn
mesh_terms: D001487:Basidiomycota / Q000378:metabolism*; D001711:Biotransformation; D005421:Flavoring Agents / Q000737:chemistry / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D027845:Malus / Q000737:chemistry / Q000378:metabolism*; D009812:Odorants / Q000032:analysis; D014866:Waste Products / Q000032:analysis*
chemical_list: D005421:Flavoring Agents; D014866:Waste Products
keywords: 3-Phenylpropanal; Apple pomace; Basidiomycetes; Biotransformation; Tyromyces chioneus