Production and characterisation of potato patatin–galactose, galactooligosaccharides, and galactan conjugates of great potential as functional ingredients

• Published in: Food chemistry 2014-09, Vol.158, p.480-489
• Main Authors: Seo, Sooyoun, Karboune, Salwa, Archelas, Alain
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Carboxylic Ester Hydrolases - chemistry; Food toxicology; Functional properties; Galactan; Galactans - chemistry; Galactooligosaccharides; Galactose; Galactose - chemistry; Hot Temperature; Hydrophobic and Hydrophilic Interactions; Maillard reaction; Medical sciences; Oligosaccharides - chemistry; Plant Extracts - chemistry; Plant Proteins - chemistry; Potato patatin; Protein structure; Protein Structure, Secondary; Solanum tuberosum - chemistry; Solubility; Spectrometry, Fluorescence; Toxicology
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.02.141

•Glycated patatins (PTT) with galactose, galactooligosaccharides (GOSs) and galactan were produced.•Infrared and fluorescence spectroscopy data revealed significant changes in structures of PTT upon glycation.•Glycation with GOSs and galactan led to more heat-stable forms of PTT with high unfolding temperatures.•PTT:galactose conjugates exhibited similar thermal/pH stability as native PTT, but higher emulsifying stability.•An improvement in the antioxidative activity of PTT was obtained upon glycation with GOSs and galactan. Potato proteins are of high interest because of their high nutritional quality and multiple health benefits, but they are currently undervalued due to their limited solubility and stability. Glycated patatin (PTT) with galactose, galactooligosaccharides (GOSs) and galactan were produced through the Maillard reaction and characterised structurally and functionally. Fourier-transform infrared and fluorescence spectroscopy data revealed important changes in total secondary structures through glycation with GOSs (61.2%) and galactan (36.7%) and also significant tertiary structural changes leading to an exposure of tryptophan residues. These structural changes led to more heat stable forms of PTT with a higher unfolding temperature (70–90°C) than the unmodified protein (50–70°C) and with higher antioxidant activity. PTT:galactose conjugates exhibited similar thermal stability and pH-structural behaviour to native PTT. However, the high level of galactose conjugation to PTT and increased exposure of hydrophobic residues led to a significant increase in its emulsifying stability at pH 3.