Enrichment of bread with soymilk using response surface methodology

•The results of this study have demonstrated that soymilk can be a good alternative to water in the bread-making process.•The total substitution of water with soymilk improved the protein content of the bread by almost 15 %.•The inclusion of soymilk in the bread production did not affect the sensory quality.•The inclusion of soymilk in the bread production positively affected the crust color of the bread.