Interactions between additives: Its effect on sorbate stability and Z. bailii minimum inhibitory concentration in model aqueous systems resembling salad dressings

CASTRO, M; OSCAR ALFREDO GARRO; CAMPOS, CA; GERSCHENSON, LN

FOOD SCIENCE AND TECHNOLOGY INTERNATIONAL

SAGE PUBLICATIONS LTD

Año: 2002 vol. 8 p. 33 - 39

1082-0132

The effect on sorbate stability of several additives (EDTA, ascorbic and acetic acids) frequently present in the formulation of salad dressings, and the minimal inhibitory concentration (MIC) of sorbate concerning Z. bailii growth in the presence of that additives were studied in aqueous model systems of pH 3.5. The addition of EDTA, ascorbic acid and the use of acetic acid protected sorbic acid from destruction. In particular, the presence of 0.075 g/kg of EDTA was essential for minimizing sorbates destruction and keeping, after 90 days of storage at 33 °C, its residual concentration above 0.400 g/kg. This value is the MIC for inhibiting the growth of Z. bailii when systems were packed in PET flasks and citric and acetic acids were used as acidulants. Packaging material, acidifying agent and EDTA level showed a strong influence on the effect of EDTA on sorbates stability. As an example, in the case of systems acidified only with citric acid and containing 0.075 g/kg or 0.500 g/kg of EDTA, it was necessary the use of glass flasks and the lowest concentration of EDTA to get a residual preservative concentration above the MIC after 90 days of storage at 33 °C.(A)