TY - JOUR
T1 - Protein extraction from oat
T2 - Isoelectric precipitation and water-based extraction
AU - Ha, Solange M.L.
AU - de Bruijn, Wouter J.C.
AU - Vreeke, Gijs J.C.
AU - Bruins, Marieke E.
AU - Nieuwland, Maaike
AU - van der Goot, Atze Jan
AU - Keppler, Julia K.
PY - 2025/6
Y1 - 2025/6
N2 - Protein extraction by alkaline extraction-isoelectric precipitation (AE-IEP) uses alkaline conditions that contribute to off-colour formation, through auto-oxidation of inherent phenolic compounds. We aimed to develop an alternative protein extraction process yielding comparable protein content to AE-IEP while avoiding alkaline conditions. It was hypothesised that a water-based extraction (WBE) of oats would yield lightly coloured native proteins. Protein contents and yields were determined using a newly established nitrogen-to-protein conversion factor of 5.12, based on the amino acid composition. WBE led to a comparable protein content to AE-IEP (69.5 % vs 70.1 % dry matter (DM)), but a 2.5 times lower yield (0.27 g/g protein DM). SDS-PAGE and quantitative proteomics revealed a protein composition of 60 % globulins and 40 % prolamins in both concentrates. A similar protein nativity was observed using differential scanning calorimetry. The WBE yielded in a lighter-coloured protein powder. The low protein yield of water-based extraction is currently a limitation for industrial applications. Nevertheless, this simple process can be used as a pre-treatment for AE-IEP to produce a more neutral-coloured powder. This study expands the knowledge on protein extraction from oats by comparing novel extraction methods with classic AE-IEP and establishing the nitrogen-to-protein conversion factor for oats.
AB - Protein extraction by alkaline extraction-isoelectric precipitation (AE-IEP) uses alkaline conditions that contribute to off-colour formation, through auto-oxidation of inherent phenolic compounds. We aimed to develop an alternative protein extraction process yielding comparable protein content to AE-IEP while avoiding alkaline conditions. It was hypothesised that a water-based extraction (WBE) of oats would yield lightly coloured native proteins. Protein contents and yields were determined using a newly established nitrogen-to-protein conversion factor of 5.12, based on the amino acid composition. WBE led to a comparable protein content to AE-IEP (69.5 % vs 70.1 % dry matter (DM)), but a 2.5 times lower yield (0.27 g/g protein DM). SDS-PAGE and quantitative proteomics revealed a protein composition of 60 % globulins and 40 % prolamins in both concentrates. A similar protein nativity was observed using differential scanning calorimetry. The WBE yielded in a lighter-coloured protein powder. The low protein yield of water-based extraction is currently a limitation for industrial applications. Nevertheless, this simple process can be used as a pre-treatment for AE-IEP to produce a more neutral-coloured powder. This study expands the knowledge on protein extraction from oats by comparing novel extraction methods with classic AE-IEP and establishing the nitrogen-to-protein conversion factor for oats.
KW - Nitrogen-to-protein conversion factor
KW - Oat protein composition
KW - Off-colour formation
KW - Plant protein extraction
KW - Protein modification
U2 - 10.1016/j.fufo.2025.100591
DO - 10.1016/j.fufo.2025.100591
M3 - Article
AN - SCOPUS:85219712966
SN - 2666-8335
VL - 11
JO - Future Foods
JF - Future Foods
M1 - 100591
ER -