Measuring pH of Liquid Culture Media
Application Method

pH Measurement of Liquid Culture Media

Application Method

Reduce Errors by Choosing the Right Sensor to Measure pH of Liquid Culture Media

pH of Liquid Growth Media
pH of Liquid Growth Media

Measuring the pH of liquid culture media can be challenging. The complex composition of growth media makes accurate pH measurement difficult when using a conventional sensor. Common challenges include fluctuations in readings due to reduced outflow of electrolyte or junction clogging when proteins and sulfides present in the sample interact with silver ions and form precipitate. Issue such as these can increase sensor response time and affect the overall accuracy of the measurement process, indicating the need for a specialized sensor when measuring the pH of liquid culture media.

METTLER TOLEDO's InLab® Max Pro ISM proves to be ideal sensor for measuring the pH of liquid culture media. The sensor has an immovable glass sleeve junction that ensures stable readings and quick response times due to faster outflow of electrolyte. The sensor design makes it easy to clean and reduces the potential for junction clogging. A robust HA glass sensing membrane tolerates highly alkaline pH conditions without compromising accuracy. Taken together, these feature make the InLab Max Pro ISM highly effective when measuring the diverse pH range of liquid culture media.

To learn more about how this robust sensor can help you obtain fast, accurate and reliable results when measuring the pH of liquid culture media, download the application note now.

Unstable readings while measuring the pH of liquid culture media?
Watch our video to see how METTLER TOLEDO sensors can help overcome challenges.

Frequently Asked Questions (FAQs): Accurately Measuring the pH of Liquid Culture Media

What is liquid culture media?
Liquid media or nutrient broths are the most common media to support the growth of microorganisms. These microorganisms are important for bioprocesses such as development of food ingredients pharmaceuticals and chemicals, or can be important for certain types of laboratory testing.

What is the common composition of a liquid culture media?
Any growth media would generally consist of the following:

  1. A carbon source such as glucose
  2. A source of amino acids and nitrogen
  3. Various salts
  4. Water

What is the difference between liquid culture media and solid media?
Liquid media are often mixed with agar and poured into sterile petri dishes to create solid growth media.

Why is measuring the pH of liquid culture media important?
Apart from assessing the complete nutritional composition, stable pH becomes vital for optimum microbial growth in culture media. The pH of a culture medium should provide favorable H+ ion concentrations that are suitable for microorganism growth.
Enzymes present within bacteria are affected by pH. The alteration of pH causes their denaturation and also brings about an alteration of the ionic charges on the molecule. Usually, this causes a loss of the catalytic properties of the enzymes which halts metabolism. This has an adverse effect on microbial growth despite the presence of a nutrient-rich medium, which can cause test results to be in accurate or produce other issues.

What Is the optimum pH for growing microorganisms in a liquid culture media?
Most bacteria grow at a pH of 6.5 to 7.0, which is near neutral. Some bacteria can live in acidic environments with pH values as low as 1.0.