Extra Virgin Olive Oil Yields Superior Sottoli in Puglia

For cen­turies, the peo­ple of the south­ern Italian region of Puglia have used olive oil to pre­serve their agri­cul­tural pro­duce, ensur­ing its avail­abil­ity long after har­vest.

Since ancient times, veg­eta­bles stored in con­tain­ers such as amphoras have been cov­ered with olive oil. The Romans were well aware of its food-pre­serv­ing qual­i­ties.

Consumers of that era could enjoy off-sea­son foods, and oil-pre­served items fueled the food trade for cen­turies.

Moreover, olive oil has been read­ily avail­able in Puglia for cen­turies. Today, the region remains the heart of olive oil pro­duc­tion in Italy.

Nowadays, pro­duce pre­served in olive oil, known as sot­toli, rep­re­sent a sig­nif­i­cant por­tion of the food mar­ket in Puglia and through­out Italy.

Recent data indi­cates that 72 per­cent of Italians rou­tinely con­sume sot­toli, with sales exceed­ing 84,800 tons per annum and a total turnover for Italian pro­duc­ers of nearly €700 mil­lion.

“The most pop­u­lar sot­toli orig­i­nate from the Apulian tra­di­tions; they include arti­choke, car­damom, egg­plant and tomato,” said Gennario Belfiore, owner of his family’s food pre­serves shop in Matera.

Lampascioni bulbs, dipped and pre­served in extra vir­gin olive oil, are sold online glob­ally.

These veg­eta­bles grow under­ground, almost exclu­sively in Puglia’s arid and cal­care­ous soil and neigh­bor­ing Basilicata. They pos­sess a unique fla­vor, intense and slightly bit­ter, and are a sta­ple of Apulian cui­sine.

Apulian tra­di­tion also fea­tures turnips, chili pep­pers, ground chili, dried toma­toes, zuc­chini, gar­lic, spicy gar­lic, wild veg­eta­bles, onions, capers, chicory, puntarelle chicory and pep­pers.

“There are hun­dreds of dif­fer­ent sot­toli crafted by Apulian grow­ers and pre­served with olive oil,” Belfiore said. ​“Not only veg­eta­bles but also cheeses like pecorino and a long list of local recipes which per­fectly com­bine food with a bath of extra vir­gin olive oil.”

Recipes include dried tomato rolls with capers and anchovies, puntarelle sal­ads and cereal- and legume-based soups.

The in-olive oil preser­va­tion tech­nique and its asso­ci­ated fla­vors became so pop­u­lar that today, sot­toli are used by many regard­less of the sea­son; some­times, they might even be cho­sen over the equiv­a­lent fresh prod­ucts.

The exquis­ite nuances of locally grown toma­toes dipped in extra vir­gin olive oil are fea­tured in the fill­ings of the local puc­cia, a very large panino (sand­wich) that remains wildly pop­u­lar.

Lorenzo Maggi, a local cui­sine expert, took a bite while look­ing out at the beau­ti­ful coast­line of Salento.

While toma­toes are grown through­out the sum­mer and can eas­ily be found fresh on local mar­ket shelves, most of the fill­ing in Maggi’s puc­cia is two years old.

“The toma­toes were so good at the begin­ning,” he told Olive Oil Times. ​“And they have been sit­ting with extra vir­gin olive oil for over two years. Their fla­vors were not only retained; they now con­vey a spe­cific round fla­vor and a crispy tex­ture of which I am fond.”

Local puc­cia mak­ers, one of the most pop­u­lar street food ven­dors in the south­ern Italian region, tend to use fresh, sea­sonal prod­ucts in their panini. However, some fla­vors can only come from foods pre­served in olive oil.

Moreover, these nat­u­rally-pre­served prod­ucts allow them to diver­sify their pucci beyond the bound­aries of sea­sonal recipes.

“Pizzerias and restau­rants also use them year-round, some­times to give their appe­tiz­ers a tasty twist, and some­times to char­ac­ter­ize a serv­ing bet­ter,” Maggi said.

In recent years, the ris­ing prices of extra vir­gin olive oil have pushed a sig­nif­i­cant por­tion of the indus­try to focus on dif­fer­ent pre­serv­ing fats.

“It surely makes sense to use extra vir­gin olive oil for food pre­serves, but at what cost?” asked Donato Palancia, an ole­ol­o­gist and olive oil tech­ni­cian at Farchioni Olii.

“Olive oil has become a sig­nif­i­cant cost for food-pre­serv­ing indus­tries,” he added. ​“Only a few oper­a­tors can afford to use it. I see many indus­tries not using extra vir­gin olive oil any­more, and some not even olive oil.”

Despite the higher costs, Belfiore said extra vir­gin olive oil dif­fer­en­ti­ates his prod­ucts.

“It pairs with pro­cess­ing that hap­pens at the opti­mal moment of mat­u­ra­tion, so the qual­i­ties of our prod­ucts are retained,” he said. ​“The main dif­fer­ence between arti­sanal in-extra vir­gin olive oil qual­ity pre­serves and indus­trial food pre­serves avail­able from large retail­ers is taste, fla­vor and crisp­ness.”

Like some com­peti­tors, Belfiore’s com­pany exports extra vir­gin olive oil-based sot­toli to Europe, the United States and Canada. ​“We are also see­ing grow­ing inter­est from Japan and New Zealand,” he said.

Belfiore added that sot­toli has even helped intro­duce Mediterranean veg­eta­bles to global audi­ences, specif­i­cally cit­ing arti­choke sot­toli in Japan.

Whether arti­sanal or indus­trial in ori­gin, in-oil pre­serves require pre­cise pro­cess­ing pro­ce­dures built on under­stand­ing the risks posed by the pos­si­ble growth of bac­te­ria and other microor­gan­isms inside the prod­uct.

“All fats are effi­cient preser­va­tion tools for a fun­da­men­tal rea­son: they reduce con­tact with oxy­gen and there­fore min­i­mize oxi­da­tion reac­tions,” said Giancarlo Colelli, a full pro­fes­sor at the Apulian University of Foggia’s Science of Agriculture, Food and Environment depart­ment.

Oxidation can alter food, affect­ing its color and nutri­tional qual­ity. Exposure to oxy­gen causes ran­cid­ity, a com­mon olive oil defect.

By remov­ing oxy­gen from the food con­tain­ers, microor­gan­isms that need oxy­gen to grow can­not mul­ti­ply.

“That is not only good news; it can also be bad news,” Colelli warned. ​“While those microor­gan­isms will not grow, it also means that another class of microor­gan­isms, those that can grow with­out oxy­gen, will face much less com­pe­ti­tion and might develop more eas­ily.”

If the prod­ucts are not cor­rectly san­i­tized, tox­ins could develop and endan­ger con­sumers’ lives. Every year in Italy, hun­dreds of peo­ple suf­fer from intox­i­ca­tion of this kind, almost exclu­sively from home­made in-oil food pre­serves.

“I never eat home­made sot­toli because fol­low­ing proper pro­duc­tion pro­ce­dures is key, and that does not always hap­pen in a house­hold,” Colelli said. ​“Producers imple­ment a series of obsta­cles to pre­vent the growth of bac­te­ria and tox­ins.”

Examples of these obsta­cles include acid­i­fi­ca­tion. Whether by adding an acid or nor­mal fer­men­ta­tion, a lower pH con­di­tions the envi­ron­ment, pre­vent­ing tox­ins from form­ing.

“Take, for instance, egg­plant in oil. To make a prod­uct sta­ble over time, pro­duc­ers acid­ify the egg­plants, usu­ally by cook­ing them to inac­ti­vate enzymes,” Colelli said. ​“We lower the acid­ity and add olive oil so molds and most aer­o­bic bac­te­ria do not develop.”

“Once we have the prod­uct, we often give it a thor­ough antiox­i­dant treat­ment and pas­teur­iza­tion,” he added. ​“This cre­ates a base that lasts for years.”

While fatty acids are very heat-sen­si­tive, Colelli said extra vir­gin olive oil still has many pro­tec­tive com­po­nents.

“Between extra vir­gin olive oil and non-extra vir­gin olive oil, the extra vir­gin oil is cer­tainly bet­ter and is there­fore rec­om­mended,” he said. ​“Especially for prod­ucts where ther­mal energy treat­ments are not nec­es­sar­ily used at the end of pro­cess­ing, extra vir­gin olive oil has the great advan­tage of degrad­ing less, tast­ing good and hav­ing a high nutri­tional value.”

• Il Sole 24
• Alimenti Salute