The lactic acid bacteria strain Enterococcus faecalis CECT7121 can provide a natural preservative for craft dry-fermented sausages, according to a new study.
The new research, published in Food Microbiology, demonstrates the protective benefits the strain has against harmful bacteria without compromising on the taste and texture of the sausage.
As part of a general shift towards natural and organic foods, consumers increasing prefer foods that do not contain synthetic preservatives or antimicrobial agents.
However, food safety must also remain a top priority for manufacturers, opening up new challenges to make safe foods that meet both the natural/organic and the food safety criteria - and for food ingredient firms to offer them appropriate ingredients to this end.
According to the researchers, the study "would indicate that the addition of E. Faecalis CECT7121 during the manufacture of craft dry-fermented sausages offers an interesting alternative for biopreservation".
They said it was an important study as poor hygiene conditions have been found to cause the loss of up to 25 per cent of the production, and there are few studies on meat products fermented at medium pH values.
Lactic acid bacteria (LAB) have been identified as the most adequate microorganism for the natural preservation of food.
The study's authors wrote: "Among the LAB, those belonging to the genus Enterococcus have antimicrobial activity, can proliferate among the pre-existing microflora and are important in the process of fermentation and preservation of food."
The E. faecalis strain was added to the manufacture of craft dry-fermented sausages and then its effectiveness as a biopreservative was analysed.
It does not contain the genes for haemolysin, which would affect the meat content, or gelatinase, which could result in a change in texture.
There were no statistical differences identified in the production of lactic acid between the control sausages and those inoculated with E.faecalis. Additionally, the pH variations were the same in both over time, reaching a minimum pH value of 5.1.
However, the test group of sausages had lower viable counts of Enterobacteriaceae, Staphylococcus aureus at the end of fermentation. Similarly, no viable entereobacteria and S.aureus were found at the end of the drying.
Also, importantly, the researchers found no difference in colour, aroma, taste or overall quality of the inoculated sausages when compared to the controls, meeting the vital criteria to provide equally tasty products without the use of artificial additives.
The researchers concluded: "In this work it was demonstrated that E faecalis CECT7121 does not express virulence factors, does not produce biogenic amines as undesirable compounds and is devoid of a capsule."
Published online ahead of print, doi:10.1016/j.fm.2008.01.008
"Characteristics of an environmental strain, Enterococcus faecalis CECT7121, and its effects as additive on craft dry-fermented sausages"
Authors: M Sparo, G G Nunez, M Castro, M L Calcagno, M A Garcia Allende, M Ceci, R Najle, M Manghi