EFFECT OF URTICA DIOICA L. ON THE GROWTH OF STAPHYLOCOCCUS AUREUS IN TRADITIONAL DRY FERMENTED SAUSAGE (“SUCUK”)

Abstract

ABSTRACT

The effect of Urtica dioica L. on the growth of Staphylococcus aureus was investigated in “sucuk,” a Turkish dry fermented sausage. The different levels of dried ground U. dioica L. (0, 1, 3 and 5%) were added to sucuk batters, and these batters were contaminated with S. aureus (10⁴ cfu/g). Numbers of S. aureus, Micrococcus/Staphylococcus and lactic acid bacteria (LAB) were determined during the ripening period. In addition, values of pH and a_w were analyzed.

The different usages of U. dioica L. and the ripening period had very significant effects on pH value and on S. aureus numbers (P < 0.01). Because U. dioica L. increased the value of pH, initial pH value was determined above 6.0 in groups including U. dioica L. During fermentation, the pH did not decrease rapidly in all groups (including the control). Because of this situation, the S. aureus number was increased. The usage of U. dioica L. has a very significant effect (P < 0.01) on the number of Micrococcus/Staphylococcus but does not have any effect on the numbers of LAB (P > 0.05). The a_w value was affected very significantly (P < 0.01) by U. dioica L. addition.

PRACTICAL APPLICATIONS

Staphylococcus aureus is an important foodborne pathogen in fermented dry sausage like “sucuk.” The behavior of this pathogen has not been investigated in fermented meat products with Urtica dioica L. In this research, the effects of different levels of U. dioica L. on the behavior of S. aureus were determined during sucuk production. The use of U. dioica L. increased the pH value in sucuk batter. Because of this, S. aureus growth was better in sucuks containing U. dioica L. than in the control group. In order to control the growth of S. aureus, lactic acid bacteria is required to be used as starter culture in sucuk with U. dioica L. as well.