Microbiological and sensory evaluation of meat sausage using thyme (Thymus vulgaris, L.) essential oil and powdered beet juice (Beta vulgaris L., Early Wonder cultivar)

Essential oils have been studied to replace synthetic chemical preservatives, among these oils, the thyme essential oil stands out. However, in addition to promoting microbial control, synthetic chemical preservatives impart a characteristic color to inlaid products, a parameter not attained by the application of essential oils. This study aimed to evaluate the effect of the joint addition of thyme essential oil and powdered beet juice to meat sausage, for a partial or total reduction of the addition of nitrates and nitrites. The thyme essential oil showed a high inhibitory action against Staphylococcus aureus and Escherichia coli in the concentration of 9.17 mg/mL, and bactericidal effect in the concentrations of 9.17 mg/mL and 36.68 mg/mL respectively, in all tests applied in vitro. When applied to meat sausages, it showed an inhibitory effect against coagulase-positive Staphylococcus, reducing the microorganism count, and partial inhibition of aerobic mesophilic bacteria. No interference was observed in the multiplication of thermotolerant coliforms in the meat product. When evaluated sensorially, the sausage presented good general acceptability, with acceptance levels above 75%. The combined uses of thyme essential oil and powdered beet juice showed potential viability for use in substitution for nitrates and nitrites in meat sausages. •Thyme essential oil has antimicrobial activity in vitro against Staphylococcus aureus and Escherichia coli.•Thyme essential oil and powdered beet juice promoted the control of microorganisms in meat sausages.•Meat sausages with thyme essential oil or powdered beet juice have good sensory acceptance.