Red peppers, harvested in 1999, were used to study the effect of different
preservation processes on vitamin C content. Two sets of eight fruits each were
processed in a local vegetable processing industry following two traditional procedures.
In one case, peppers in pieces were fried in olive oil and, in the second, peppers
were roasted and peeled. Then, 5 ml fresh lemon juice were added and the glass
containers of 500 g were sealed and heated at 1038C for 40 min. These conditions are
the standard conditions in the product elaboration processes. The vitamin C content
was determined after 1 year of storage at room temperature. Another third set of 15
peppers was transported to the laboratory to be subjected to different preservation
processes: (i) blanching in boiling water during 5 min; (ii) freezing in a domestic
freezer, with and without a previous blanching step and storage at /188C during 30
days; (iii) drying in an oven set at 508C during 7 days; and (iv) freeze-drying in a
VIRTIS GENESIS 12 LE system (Biopharma Process Systems, Hampshire, UK).