Phenols in Olive Mill Byproducts Can Be Effective Preservatives in Fresh Meats

According to a recent study con­ducted in Italy, phe­nols from olive veg­e­ta­tion water can be effec­tive nat­ural preser­v­a­tives in fresh meat.

Olive Oil Times had the oppor­tu­nity to pre­view research that will be pub­lished in the November issue of LWT Food Science and Technology and which were achieved through the close col­lab­o­ra­tion of Stefania Balzan, Barbara Cardazzo, Enrico Novelli and Luca Fasolato from the University of Padova; Agnese Taticchi, Stefania Urbani and Maurizio Servili from the University of Perugia; Giuseppe Di Lecce and Maria Teresa Rodriguez-Estrada from the Alma Mater Studiorum-University of Bologna; and Izaskun Berasategi Zabalza from the University of Navarra.

“Nowadays, the replace­ment of chem­i­cal addi­tives with nat­ural com­pounds in food prepa­ra­tions is a mat­ter of great inter­est, both to con­sumers and to the food indus­try,” Giuseppe Di Lecce told Olive Oil Times. ​“Consumers not only have a strong expec­ta­tion of foods with the fewest or low­est pos­si­ble level of addi­tives but also tend to sharply dis­tin­guish between nat­ural and syn­thetic extra ingre­di­ents.”

Many peo­ple believe that processed meat is unhealthy. ​“The con­sump­tion of fresh ground meat prepa­ra­tions is very wide­spread due to their pleas­ant taste and ease of cook­ing, but accord­ing to a sur­vey on the health ben­e­fits of processed meats, half of the respon­dents believed that processed meat con­tains large quan­ti­ties of harm­ful chem­i­cals,” said Di Lecce, who has also served as a judge or panel leader at all five edi­tions of the annual New York International Olive Oil Competition (NYIOOC).

Nevertheless, food addi­tives like antiox­i­dants must be used to con­trol lipid oxi­da­tion dur­ing food pro­cess­ing and stor­age, in order to pre­vent ran­cid­ity, dete­ri­o­ra­tion of sen­sory qual­ity and pro­duc­tion of free rad­i­cals which are involved in a series of chronic degen­er­a­tive patholo­gies other than can­cer.

“On this basis, we wanted to test an alter­na­tive approach to the use of syn­thetic addi­tives in this type of food, as well as to ver­ify the effi­ciency of nat­ural antiox­i­dants,” he explained.

The well-estab­lished pos­i­tive con­tri­bu­tion of extra vir­gin olive oil to human health is mainly attrib­uted to the antiox­i­dant actions of a com­pos­ite class of hydrophilic phe­nols. Accordingly, in this study researchers used a puri­fied phe­no­lic extract obtained from fresh olive veg­e­ta­tion water aris­ing from the Moraiolo olive cul­ti­var.

The entire exper­i­ment was per­formed in three repli­cates, each one using slightly more than 40 kg (88.1 lbs) of shoul­der and belly pork that was ground, mixed with salt and divided into three batches. With the goal of avoid­ing sec­ondary and non-stan­dard­iz­able antiox­i­dant effects from other ingre­di­ents, no spices were added.

Each batch was fur­ther mixed and stuffed into bovine cas­ings by using a hydraulic pis­ton-type stuffer. The sausages, nearly 100 g (3,52 oz) each, were left to drip and then stored with­out pack­ag­ing in a dis­play cab­i­net under alter­nat­ing expo­sure to flu­o­res­cent light to sim­u­late retail shops and butcheries.

At zero, 7 and 14 days, a rep­re­sen­ta­tive num­ber of sausages from each batch were sam­pled and frozen in liq­uid nitro­gen before being stored at 80°C (?112°F) until analy­sis. At the same times, the same num­ber of sausages from each batch was cooked, cooled in an ice bath, stored for 72 hours at 2 – 4°C (35.6 – 39.2°F) and then frozen in liq­uid nitro­gen before being stored at ‑80°C (-112°F) until an analy­sis.

The meat prod­ucts were eval­u­ated before and after an aer­o­bic stor­age for 14 days. Adding the phe­nol extract at dif­fer­ent con­cen­tra­tions, researchers found a decrease in pH, dia­cyl­glyc­erols, per­ox­ide value, thio­bar­bi­turic acid reac­tive species, and cho­les­terol oxi­da­tion prod­ucts. Sensory analy­sis revealed sig­nif­i­cant dif­fer­ences between con­trol sam­ples and those enriched with the extract, but the enriched sam­ples were never con­sid­ered unpleas­ant by the pan­elists.

The results revealed that the puri­fied phe­nol extract showed effi­cacy in pre­vent­ing both pri­mary and sec­ondary lipid oxi­da­tion and in lim­it­ing the oxida­tive degra­da­tion of cho­les­terol in raw and cooked fresh pork sausages. Phenols proved to be an effec­tive antiox­i­dant in these food prod­ucts, thus result­ing a poten­tial ingre­di­ent to ensure qual­ity and safety of meat prepa­ra­tions.

“This approach has many advan­tages,” Di Lecce observed. ​“For the meat indus­try, in a per­spec­tive of a pro­gres­sive reduc­tion in the use of syn­thetic addi­tives toward the so-called clean label; for con­sumers, in terms of ben­e­fits from the health stand­point; for the olive oil sec­tor, with a view to a more sus­tain­able approach in man­ag­ing byprod­ucts and pro­vid­ing an added value to the waste­water,” Di Lecce con­cluded.