Microbiological quality of marinated vacuum-packaged chicken breast fillets

Abstract

This study evaluated the effect of dipping in a marinade solution on the microbiological quality of chicken fillets packaged under vacuum and stored at 4 °C. A total of 120 skinless breast fillets (used for the 2 trials) were marinated in control and three different treatment solutions: 6% NaCl (control), 6% NaCl and 2% sodium tripolyphosphate (STP) (T1), 6% NaCl and 2% sodium citrate (T2), and solution with 6% NaCl, 1% STP and 1% sodium citrate (T3). The fillets‐to‐marinating‐solution ratio was 1:2. After five hours of marination, breasts fillets were vacuum-packaged. At each sampling period (day 0, 7, 14, 21 and 28 of storage) 3 treatments and 3 control breast fillets were randomly selected for Enterobacteriaceae, Total viable count (TVC), Lactic acid bacteria (LAB) and anaerobic bacteria enumeration. In samples of the fillets marinated in a solution with 1% and 2% sodium citrate, a significantly lower number of Enterobacteriaceae (2.70 log CFU/g, 2.64 log CFU/g, P < 0.05, respectively) was found compared to the other two treatments, while the addition of 2% sodium citrate led to Enterobacteriaceae count decrease by 1.85 log CFU/g by the day 28. TVC and LAB count increased during storage in all treatments except in T2 treatment. The highest TVC was in control and in treatment with 2% STP (7.03 log CFU/g, 6.94 log CFU/g, P > 0.05, respectively). The addition of 2% sodium citrate inhibited LAB growth ranging from 2.33 to 2.90 log CFU/g during storage. The most significant increase was in anaerobic bacterial count over time, wherein their numbers were higher than 7 log CFU/g at the end of the storage, with the exception in the T2 treatment (3.97 log CFU/g on day 28). Based on the microbiological data obtained, the use of vacuum-packaging in combination with 2% sodium citrate marinade solution may be an effective means of extending the shelf life of the chicken breast fillets.

U ovom istraživanju ispitivao se uticaj korišćenja marinade na mikrobiološki status pilećih filea upakovanih u vakuum i skladištenih na temperaturi do 4 °C. Ukupno 120 pilećih filea bez kože (korišćenih za dva ponavljanja) marinirano je u kontrolnom rastvoru i tri različite vrste eksperimentalnih rastvora marinada: 6% NaCl (kontrola), 6% NaCl i 2% natrijum tripolifosfat (STPP) (T1), 6% NaCl i 2% citrat (T2) i rastvor sa 6% NaCl, 1% STPP i 1% citrata (T3). Odnos filea i marinade bio je 1:2. Nakon pet sati mariniranja filei su upakovani u vakuum. Svakog dana uzorkovanja (0, 7, 14, 21 i 28 dan skladištenja) po tri uzorka iz kontrolne i oglednih grupa su nasumično odabrani za utvrđivanje broja Enterobacteriaceae, ukupnog broja mezofilnih bakterija (UBB), bakterija mlečne kiseline (BMK) i anaerobnih bakterija. U uzorcima filea mariniranih u rastvoru sa 1% i 2% citrata utvrđen je značajno niži broj Enterobacteriaceae (2,70 log CFU/g, 2,64 log CFU/g, P < 0,05, pojedinačno), u odnosu na druge dve grupe, dok je dodavanje 2% citrata u marinadu dovelo do pada broja Enterobacteriaceae za 1,85 log CFU/g do 28 dana. Ukupan broj mezofilnih bakterija i broj BMK rastao je u svim grupama osim u T2 grupi. Najviši UBB bio je u kontrolnoj i grupi sa 2% STPP (7,03 log CFU/g, 6,94 log CFU/g, P > 0,05, pojedinačno). Dodavanje 2% citrata u marinadu inhibiralo je rast BMK i njihov broj se kretao u opsegu od 2,33 do 2,90 log CFU/g tokom skladištenja. Utvrđen je najznačajniji porast u broju anaerobnih bakterija tokom vremena i on je bio viši od 7 log CFU/g na kraju perioda skladištenja sa izuzetkom u T2 grupi (3,97 log CFU/g, 28. dan). Na osnovu dobijenih podataka mikrobioloških analiza može se zaključiti da vakuum pakovanje u kombinaciji sa 2% citrata u rastvoru marinade može biti efikasan način za produžavanje održivosti pilećeg filea. M