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A Modification of Lerke Enzymic Test for Histamine Quantification
J J Rodriguez-Jerez1, M Ausilia Grassi2, Tiziana Civera2
1Higiene e Inspección de los Alimentos, Facultad de Veterinaria, Universidad Autónoma de Barcelona, 08193, Bellaterra (Barcelona), Spain.
Journal of Food Protection
|May 25, 2019
Summary
This study optimized the Lerke enzymic method for histamine determination. The modified method uses a 580 nm wavelength and 15-minute incubation for reliable, cost-effective screening of histamine in food and bacterial samples.
Area of Science:
- Analytical Chemistry
- Biochemistry
Background:
- Histamine determination is crucial for food safety and microbiology.
- Existing methods for histamine analysis may require lengthy procedures or high costs.
Purpose of the Study:
- To modify and optimize the Lerke enzymic method for histamine determination.
- To establish reliable and efficient conditions for histamine analysis.
Main Methods:
- Modification of the Lerke enzymic method.
- Investigation of optimum wavelength and incubation time at 37°C.
- Testing linearity of the method for histamine concentration.
Main Results:
- An optimum wavelength of 580 nm was identified.
- A 15-minute incubation time was found to be optimal.
- Linearity was observed for histamine concentrations between 1 and 25 ppm (μg/g).
Conclusions:
- The modified Lerke method offers a reliable, low-cost, and rapid technique for histamine screening.
- This optimized method requires minimal sample preparation.
- The method is suitable for analyzing histamine in food samples and bacterial strains.
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