A soy protein product is obtained by extracting a soy protein source material with an aqueous calcium salt solution to form an aqueous soy protein solution and adjusting the pH of the mixture of aqueous soy protein solution and residual soy protein source to a pH of about 1.5 to about 4.4. The acidified soy protein solution then is separated from the residual soy protein source. The acidified soy protein solution may be dried, following optional concentration and diafiltration, to provide the soy protein product.