Ginja vs. cereja-ácida
Both ginja and cereja-ácida refer to the same fruit, the sour cherry (Prunus cerasus), but their usage depends on geography and context. In Portugal, ginja is the everyday word used for the fruit and its byproducts. In Brazil, where this specific fruit is not native and rarely found fresh, the descriptive term cereja-ácida is often used to specify the flavor or distinguish it from the sweet cherry (cereja), though ginja may appear on labels of imported goods.
Ginja
B2This is the standard term in European Portuguese for the sour cherry. It is culturally significant in Portugal, especially for the production of a famous liqueur called Ginjinha. In Brazil, ginja is less recognized by the general public and is mostly seen on jars of imported preserves or liqueurs.
Quando visiteres Óbidos, tens de provar o licor de ginja num copo de chocolate.
(When you visit Óbidos, you have to try the sour cherry liqueur in a chocolate cup.)
A compota de ginja é muito popular no pequeno-almoço em Portugal.
(Sour cherry jam is very popular for breakfast in Portugal.)
Estas ginjas são demasiado azedas para comer cruas.
(These sour cherries are too tart to eat raw.)
Comprei um frasco de ginja em calda importado de Portugal.
(I bought a jar of sour cherries in syrup imported from Portugal.)
A cor da ginja é geralmente mais escura que a da cereja comum.
(The color of the sour cherry is usually darker than that of the common cherry.)
Cereja-ácida
B2Literally translating to acidic cherry, this composite word is used primarily in Brazil and in botanical contexts to describe the specific variety of the fruit. Since the fruit is rare in Brazil, speakers use cereja-ácida to clarify that they are not talking about the standard sweet cherry (cereja).
Para fazer esta torta americana, precisamos de cereja-ácida em vez de cereja doce.
(To make this American pie, we need sour cherry instead of sweet cherry.)
É muito difícil encontrar cereja-ácida fresca nas feiras do Brasil.
(It is very difficult to find fresh sour cherry at street markets in Brazil.)
O termo científico para a cereja-ácida é Prunus cerasus.
(The scientific term for the sour cherry is Prunus cerasus.)
Gosto de balas com sabor de cereja-ácida porque não são enjoativas.
(I like sour cherry flavored candies because they are not cloying.)
A receita sugere usar suco de cereja-ácida para marinar a carne.
(The recipe suggests using sour cherry juice to marinate the meat.)
Summary
In short, use ginja if you are in Portugal or referring to Portuguese products like liqueur and jams. Use cereja-ácida if you are in Brazil or need to technically describe the tart variety of the fruit to distinguish it from a sweet cherry.