title: Binding of carbonyl flavours to canola, pea and wheat proteins using GC/MS approach.
abstract: Interactions of homologous aldehydes (hexanal, heptanal, and octanal) and ketones (2-hexanone, 2-heptanone, and 2-octanone) to salt and alkaline-extracted canola and pea proteins and commercial wheat gluten were studied using GC/MS. Long-chain aldehyde flavours exhibited higher binding affinity, regardless of protein type and isolation method. Salt-extracted canola protein isolates (CPIs) revealed the highest binding capacity to all aldehydes followed by wheat gluten and salt-extracted pea protein isolates (PPIs), while binding of ketone flavours decreased in the order: PPIs>wheat gluten>CPIs. Two aldolisation products, 2-butyl-2-octenal and 2-pentyl-2-nonenal, were detected from the interactions between CPIs with hexanal and heptanal, respectively. Protein thermal behaviour in the presence of these compounds was analysed by differential scanning calorimeter, where decreased ΔH inferred potential conformational changes due to partial denaturation of PPIs. Compared to ketones, aldehyde flavours possessed much higher "unfolding capacity" (lower ΔH), which accounted for their higher binding affinities.
authors.affiliation: Department of Food Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Food Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada. Electronic address: susan_arntfield@umanitoba.ca.
authors.forename: Susan D
authors.initials: SD
authors.lastname: Arntfield
mesh_terms: D005229:Fatty Acids, Monounsaturated / Q000737:chemistry*; D005421:Flavoring Agents / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D018532:Pisum sativum / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D000074262:Rapeseed Oil; D014908:Triticum / Q000737:chemistry*
chemical_list: D005229:Fatty Acids, Monounsaturated; D005421:Flavoring Agents; D011506:Proteins; D000074262:Rapeseed Oil
keywords: Canola; Pea; Protein thermal properties; Protein–flavour binding; Wheat