UV-Vis Spectroscopy - Use in Bioprocess and Fermentation Monitoring

Advancements in research development in bioprocess and fermentation for different food product applications, there is a necessity for real-time analytical tools to monitor bioprocess and fermentation. 

There are several methods used for bioprocess and fermentation monitoring. Some of the spectrophotometer methods that are used for bioprocess and fermentation monitoring are UV-Visible, Infrared(IR), and Raman. 

In this article main principles and UV-Vis spectrophotometer developments to monitor bioprocess and fermentation are discussed.

There is a need for a rapid and affordable method to monitor bioprocess and fermentation in biological and food applications, resulting in an increasing need for real-time analytical tools. 

Fermentation monitoring in various food and beverage applications such as beers, wines, and cultured dairy products is required to determine the quality and effectiveness during manufacturing. 

In this process, it is required to perform a quantitative analysis of the sugar content and its transition during the fermentation of a product. UV Vis spectrophotometers are used to perform such a quantitative analysis and to deliver quality products. 

Origin of the UV-Vis Spectrophotometer

Spectroscopy is an optical technique where absorption, transmission or reflection of light by the sample is measured. 

Light is an electromagnetic wave that travels in a certain wavelength. Each substance absorbs light in an unique way and so the wavelength also varies with the nature of substances. 

The two main techniques that are used to analyze food samples are atomic and molecular spectrophotometry. Recent developments in spectroscopy methods in the field of food analysis enable us to determine the food composition and help to understand the quality and safety of food. 

Various spectroscopy techniques used in food analysis is Ultraviolet and Visible (UV-Vis), near-infrared (NIR), mid-infrared (MIR), far-infrared (FIR), Raman, microwaves, radio waves, and Nuclear Magnetic Resonance (NMR). 

UV – Vis spectrophotometer is an effective method in molecular spectroscopy that uses ultraviolet and visible light that travels in a wavelength range between 200 to 800nm. 

The concentration of the analytes is measured with Beer-Lambert law in the food matrix. As a consequence of this, the chemical and physical properties of the samples can be determined and quantified.

Spectrophotometers to Detect Chemical Changes

UV/Vis spectrophotometer is an optical technique that measures the intensity of light as the light is passed through the sample. Every component in a sample has its own unique spectrum and absorbs light in a unique way. 

UV/Vis spectrophotometer measures the absorbance of light by the sample at a specific wavelength. These measurements of absorbance, transmittance, or reflectance provide a quantitative analysis of the sample that helps to determine the chemical composition of the sample.

During the fermentation process, the sugar in the product differs at each stage. Measurement of sugar concentration fluctuates at each stage of fermentation and is measured with quantitative analysis. 

With reference to Science Direct online article Biomass and Bioenergy (Volume 35, Issue 7) real-time monitoring of sugar concentration is a key to optimizing product formation and helps to maintain a healthy environment for microorganisms. 

UV/Vis spectrophotometer is the most commonly used method that effectively monitors this fermentation process and provides real-time feedback on the sugar content of the product. The traditional fermentation process is a complex process and does not provide accurate, real-time data.

Biomass concentration measurement is another important factor in fermentation studies. Traditionally biomass was measured by separating the dead cells and viable cells and counting them with a microscope manually or counting chamber. 

Even then the measurements are taken by this traditional method are not accurate and hence optical techniques such as UV spectrophotometer, IR spectrophotometer, or Raman are preferred methods of quantitive analysis for the fermentation process.

Fermentation is the most important method in food processing for long days to preserve the quality of food products. Foods are fermented by microorganisms such as bacteria, fungi, and yeast. 

These microorganisms produce enzymes such as hydrolyze, polysaccharides, proteins, and lipids which add flavor, aromas, and texture to the food that are tasty and attractive to humans. 

It is important to analyze food composition such as sugars, amino acids, vitamins, fermentation products and detect contaminants such as pathogenic microorganisms, toxins, antibiotics, allergens, and hormones. 

It is important for food manufacturers to determine the quality and safety of foods to deliver healthy foods to their consumers. The quality and safety of the food are analyzed periodically for chemical and biological analysis. 

These analyses use chemical techniques like spectrophotometry, chromatography, electrophoresis, and some biological method such as enzymatic determination and immunoassays. 

Conclusion

UV/Vis spectrophotometer has got its great importance in the research field of various industries such as quality control, bioprocess, pharmaceutical, chemical industries, cosmetics, and more. UV/Vis spectrophotometer is widely used for testing food and beverage. 

Advancements in spectroscopy instruments provide accurate, sensitive, and robust results from the analysis. 

The quantitative analysis of the UV spectrophotometer enables the determination of the food composition and monitoring of the food samples at different stages of fermentation. This helps in producing quality and safe food for the consumers.