Whole yogurt sweetened with glucose-galactose syrup obtained by nanofiltration: Effect on galactooligosaccharides concentration, physicochemical and sensory properties

•Glucose-galactose syrup has potential as a sweetener and source of GOS when added as a partial substitute for sucrose in foods such as yogurt.•The stability of total GOS in the different yogurts sweetened with glucose-galactose syrup is not affected during 28-day refrigerated storage period.•Glucose-galactose syrup sweetened yogurts will maintain a similar sensation of sweetness and overall acceptability to the control (sucrose yogurt) when up to 25% of the sweetness provided by sucrose is replaced.•Glucose-galactose syrup enhances the quality attributes of yogurt for its possible marketing as yogurt with galactooligosaccharides.•Oligosaccharides produced from lactose are of great interest because they are considered prebiotics and the best substitutes for Human Milk Oligosaccharides (HMOS). Glucose-galactose syrup is a sweetener obtained from whey. It is scarcely industrial produced due to its low level of sweetness and lower economic competitiveness compared to other traditional sugars. However, it could be used in the food industry as a partial substitute for sucrose or glucose and as a galactooligosaccharides (GOS) source. This study aimed to evaluate the total GOS content (GOS-3 and GOS-4), physicochemical properties, and consumer acceptance of yogurts in which the sweetness usually provided by sucrose was replaced by different proportions of glucose-galactose syrup (0, 25, 50, 75 and 100%). The results showed an increase in total GOS content from 0.54 ± 0.02 gL−1 for the sucrose-sweetened yogurt to 5.52 ± 0.04 gL−1 for the yogurt with 50% inclusion of glucose-galactose syrup. Moreover, they showed stability during a storage period of 28 days. Moreover, there was an increase in the content of minerals such as: calcium, magnesium, potassium and ash. Additionally, the sensory analysis showed a greater perception of sweetness in yogurts with syrup inclusion levels from 25 to 50% and similar overall acceptability to sucrose yogurt when replacements of up to 25% of sweetness were made.