Calabria — specifically the Diamante coast (known for the Diamante peperoncino variety) and the Cosenza and Crotone areas. The peperoncino arrived in southern Italy from the New World via Spanish trade routes in the 16th century and was adopted into Calabrian cooking with a speed and thoroughness found nowhere else in Italy.
The drying and preservation of Calabrian chilli peppers is as much a cultural practice as a culinary technique. Each September, strands of red peperoncini are threaded on string (the 'nduja necklaces) and hung from balconies and pergolas throughout Calabria — a regional tradition as visually iconic as anything in Italian food culture. The drying transforms the fresh chilli: concentrating its capsaicin, deepening its colour to a deep red-orange, and developing fruity-smoky aromatic compounds absent in the fresh state. Different drying methods produce different flavour profiles.
Sun-dried Calabrian peperoncino dolce has a fruity, sweet-spicy character different from the harsh heat of fresh chilli — the drying concentrates the carotenoids and develops Maillard-adjacent aromatic compounds from the cell walls. The hot variety (piccante) has a clean, focused heat. Used together in the correct ratio, they create the specific warmth-and-fragrance of Calabrian cooking.
Sun-drying on strings preserves the fruity, bright character — ideal for the sweet variety (dolce). Oven-drying at very low heat (50-60°C, 8-12 hours) produces a more uniform product. Smoking produces the specifically Calabrian 'peperoncino affumicato' used in 'nduja and soppressata. After drying, the dried peperoncino is ground — either on its own (for pure dried chilli powder) or with salt to create a seasoning blend. The sweet (dolce) and hot (piccante) varieties are kept separate and used in different proportions for different preparations.
The best Calabrian dried peperoncino is still sun-dried — the UV exposure creates specific aromatic compounds from the carotenoids in the pepper flesh. For home drying, a food dehydrator at 55°C for 8-10 hours approximates sun-drying without the bacteria risk. Keep dried peperoncino in airtight containers away from light — the carotenoids oxidise rapidly on exposure to light.
Drying at too high a temperature — the exterior dries too fast, trapping moisture inside, and the chilli develops mould rather than drying properly. Not selecting ripe, undamaged peppers — damaged peppers rot rather than dry. Grinding without fully dry peppers — wet powder clumps and develops off-flavours. Mixing sweet and hot without measuring — the ratio of dolce to piccante determines the heat level of everything made with the dried product.
Giorgio Locatelli, Made in Italy; Slow Food Editore, Calabria in Cucina