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High-throughput pH monitoring method for application in dairy fermentations

Published online by Cambridge University Press:  22 August 2018

Valery Gutsal*
Affiliation:
Arla Innovation Centre, Agro Food Park 19, 8200 Aarhus N, Denmark
Sander Sieuwerts
Affiliation:
Arla Innovation Centre, Agro Food Park 19, 8200 Aarhus N, Denmark
Rodrigo Bibiloni
Affiliation:
Arla Innovation Centre, Agro Food Park 19, 8200 Aarhus N, Denmark
*
*For correspondence; e-mail: [email protected]

Abstract

Optimization of dairy fermentation processes often requires multiplexed pH measurements over several hours. The method developed here measures up to 90 samples simultaneously, where traditional electrode-based methods require a lot more time for handing the same number of samples. Moreover, the new method employs commonly used materials and can be used with a wider range of fluorescence readers than commercial 96-well plates with optical pH sensors. For this application, a milk-like transparent medium is developed that shows acidification properties with dairy starters that are similar to milk. Combination of this milk-like medium and 3 fluorescent indicators allow precise measurements of pH in a range of 4·0–7·0. The new method showed much higher throughput compared to the benchmark electrode systems while being as accurate, as shown by successful application for a comparison of various dairy starter cultures and for optimizing the inoculation rate.

Type
Research Article
Copyright
Copyright © Hannah Dairy Research Foundation 2018 

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