Micronized benzoic acid decreases the concentration necessary to preserve acidic beverages against Alicyclobacillus

• Published in: Journal of applied microbiology Vol. 115; no. 2; pp. 466 - 474
• Main Authors: Kawase, K.Y.F., Luchese, R.H., Coelho, G.L.
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell 01-08-2013; Oxford University Press
• Subjects: Alicyclobacillus; Alicyclobacillus - drug effects; Alicyclobacillus - ultrastructure; Benzoic Acid - chemistry; Benzoic Acid - pharmacology; Beverages - microbiology; Biological and medical sciences; Citrus; Citrus sinensis - microbiology; electron microscopy; Food Preservatives - chemistry; Food Preservatives - pharmacology; Fundamental and applied biological sciences. Psychology; Microbiology; micronization; preservative; supercritical CO2; Temperature; Benzoic acid; Alicyclobacillus; Preservative; Applied microbiology; Carbon dioxide; Micronization; Concentration; supercritical CO; Beverage; Supercritical state; Electron microscopy; preservative; electron microscopy; supercritical CO2; micronization
• ISSN: 1364-5072; 1365-2672
• DOI: 10.1111/jam.12227

Aims
The aim of this study was a challenge testing the effect of lower concentrations of micronized benzoic acid against two strains of Alicyclobacillus.
Methods and Results
The effect of micronized benzoic acid was compared with the usual levels of untreated commercial sodium benzoate and benzoic acid, at the challenge temperature of 45°C. The size of the benzoic acid particles was determined by scanning electron microscopy. The diameter of the micronized particles was around 10 μm with a maximum length of 200 μm, while the untreated preservative structures were irregular with lengths up to 500 μm. A continuous bactericidal effect against two Alicyclobacillus strains, throughout the 28‐day period, was observed with 50 mg l−1 of micronized benzoic acid, but when the untreated preservative was used, the same lethal effect was not achieved even after doubling its concentration.
Conclusions
The antimicrobial activity of benzoic acid was improved by micronization. The process proved to be an effective alternative to reduce the benzoic acid concentration necessary to ensure stability of an orange juice matrix.
Significance and Impact of the Study
The results proved that the micronization process represents an alternative to reduce the required food preservative concentration; this method increased the stability of the compound, which maintains its bioavailability.