SÃO PAULO—Brazil has created millions of new consumers in recent years but a true middle class has yet to emerge, according to former Brazilian president Fernando Henrique Cardoso.

"What has been called the rising of a new middle class is fact an increase in consumption," Mr. Cardoso said.

"We need to jump from quantity to quality," he added, referring to the poor caliber of Brazil's public services.

Speaking from his home in São Paulo's Higienópolis neighborhood, the 82-year-old credited President Dilma Rousseff and her ruling PT Workers Party for focusing on the nation's poorest citizens. Low unemployment, rising salaries and easy credit have fueled a burst of consumer spending on cellphones, appliances and other household goods.

But Mr. Cardoso, who is honorary president the opposition Brazilian Social Democracy Party, or PSDB, said creating a class of shoppers isn't the same as building a solid middle class.