title: Impact of low hydration of barley grain on β-glucan degradation and lipid transfer protein (LTP1) modifications during the malting process.
abstract: One of the objectives of the malting industry is to reduce the energy cost during kilning without major effect on malt quality. In this study, the impact of a low hydration steeping process on lipid transfer protein (LTP1) modifications and β-glucan breakdown was evaluated in low (LH) and high (HH) hydrated malts. LTP1 modifications analyzed by MS/MS revealed acylation, glycation, and disulfide bond breakage in both LH and HH malts. LTP1 free amine content measurement and fluorescence of Maillard protein adducts revealed no significant difference between LH and HH malts. Immunolabeling of LTP1 during malting highlighted the diffusion of the protein from the aleurone layer to the endosperm at the end of steeping in both LH and HH malts. By contrast, a significant higher amount of β-glucans was measured in LH malts after five days of germination, whereas no significant difference between LH and HH malts was revealed through immunostaining of β-glucans or evaluation of the endosperm integrity after seven days of germination. The possibility to reduce the effects of a low hydration steeping process on β-glucan hydrolysis by increasing germination time was discussed.
authors.affiliation: IFBM-Qualtec, Institut Francais des Boissons de la Brasserie et de la Malterie, Vandoeuvre, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Runavot
authors.forename: Benedicte
authors.initials: B
authors.lastname: Bakan
authors.forename: Nathalie
authors.initials: N
authors.lastname: Geneix
authors.forename: Luc
authors.initials: L
authors.lastname: Saulnier
authors.forename: Keltouma
authors.initials: K
authors.lastname: Moco
authors.forename: Fabienne
authors.initials: F
authors.lastname: Guillon
authors.forename: Françoise
authors.initials: F
authors.lastname: Corbineau
authors.forename: Patrick
authors.initials: P
authors.lastname: Boivin
authors.forename: Didier
authors.initials: D
authors.lastname: Marion
mesh_terms: D000215:Acylation; D002352:Carrier Proteins / Q000737:chemistry*; D050556:Fatty Acid-Binding Proteins; D005511:Food Handling / Q000379:methods*; D018525:Germination; D006031:Glycosylation; D001467:Hordeum / Q000737:chemistry* / Q000502:physiology; D047071:beta-Glucans / Q000737:chemistry*
chemical_list: D002352:Carrier Proteins; D050556:Fatty Acid-Binding Proteins; C422456:Ltp1 protein, barley; D047071:beta-Glucans