Understanding the Effects of Lactose Hydrolysis Modeling on the Main Oligosaccharides in Goat Milk Whey Permeate

• Main Authors: Caroline Thum, Valerie Weinborn, Daniela Barile, Warren C McNabb, Nicole C Roy, Juliana Maria Leite Nobrega de Moura Bell
• Format: Article
• Language: English
• Published: MDPI AG 2019-09-01
• Series: Molecules
• Subjects: lactose hydrolysis; goat milk oligosaccharides; β-galactosidase; transgalactosylation; whey; mass spectrometry; processing
• Online Access: https://www.mdpi.com/1420-3049/24/18/3294

Enzymatic hydrolysis of lactose is a crucial step to improve the efficiency and selectivity of membrane-based separations toward the recovery of milk oligosaccharides free from simple sugars. Response surface methodology was used to investigate the effects temperature (25.9 to 54.1 &#176;C) and amount of enzyme (0.17 to 0.32% <i>w/w</i>) at 1, 2, and 4 h of reaction on the efficiency of lactose hydrolysis by <i>Aspergillus oryzae</i> &#946;-galactosidase, preservation of major goat whey oligosaccharides, and on the de-novo formation of oligosaccharides. Lactose hydrolysis above 99% was achieved at 1, 2, and 4 h, not being significantly affected by temperature and amount of enzyme within the tested conditions. Formation of 4 Hexose (Hex) and 4 Hex 1 Hex and an increased de-novo formation of 2 Hex 1 N-Acetyl-Neuraminic Acid (NeuAc) and 2 Hex 1 N-Glycolylneuraminic acid (NeuGc) was observed in all treatments. Overall, processing conditions using temperatures &#8804;40 &#176;C and enzyme concentration &#8804;0.25% resulted in higher preservation/formation of goat whey oligosaccharides.