Silvio,

The way I see it is:

Batch = Fornada

"Fornada de pão" = Bread batch = todos os pães assados ao mesmo tempo

Lot = Lote

Lote de pão = Bread lot (with bread from different batchs but still put together in the same lot)

"Example Company X made a batch of 1,234 cookies, there are 10,000 cookies in this batch, in order to sell them they break the "batch" into 1,000 "lots" of 10 cookies each." (http://wiki.answers.com/Q/What_is_the_difference_between_lot_number_and_batch_number)