Thanksgiving is known as a time to celebrate the past year's harvest and give thanks.1 Around the world, many countries have their own way of celebrating the harvest season, and these festivals usually focus on gathering and feasting on foods and wines drawn from the new crops.
Image Credit: B&W Tek
It is unsurprising that many Americans overeat on Thanksgiving, with some even believing that it is their patriotic duty. However, overeating can come at a high price, as evidenced by higher numbers of people being hospitalized from food-related complications this time of the year.2
Kombucha has gained popularity in the USA.3 It is a fermented beverage of Northeastern Chinese origin. In 2016, the Americas accounted for approximately 51% of global Kombucha sales.4
Like many fermented foods, Kombucha is loaded with beneficial effects like protection against hypertension, indigestion, constipation, psoriasis, arthritis and metabolic disease.5 This means that simply adding Kombucha to a Thanksgiving spread could prevent an untimely visit to an urgent care.
Due to its ability to be implemented for both inline and online monitoring and because of its capacity for real-time, non-destructive measurements, Raman spectroscopy is a valuable process analytical technology (PAT). The B&W Tek PTRam system has previously been used to explore PAT (Glucose and Lactate Monitoring with PTRam).
Raman spectroscopy is able to monitor microbial activity in a bioreactor through tracking changes in metabolic products and media components. Microorganisms produce the two main components of Kombucha - acetic acid and ethanol - from sugar during the brewing process.6
B&W Tek has been brewing Kombucha in the lab in preparation for Thanksgiving, monitoring the process in situ with the PTRam equipped with an immersion shaft with sapphire ball probe, collecting spectra at 15-minute intervals.
Math-treated Raman spectra of 300 to 800 cm-1 region over the first three days of fermentation are shown in Figure 1. This region is comprised of carbon-oxygen bonds of sugar and skeletal vibration of carbons.7
Figure 1. Relative Raman peak height of δ(C2–C1–O1) bending vibration (415 cm-1) of Kombucha broth7 (a), and math-treated Raman spectra of the exponential sugar uptake phase (growth phase). Image Credit: B&W Tek
By following the change in these Raman bands over time, B&W Tek can track the fermentation, as shown in Figure 2. Using B&W Tek BWIQ software, a model was built that yielded an R2 value of 0.93 for validation data sets over the growth phase and 0.99 for the calibration model.
Figure 2. Calibration model and validation data of glucose concentration at measured and predicted fermentation time. Image Credit: B&W Tek
The PTRam system and Vision software were used throughout this process for data collection and real-time monitoring. The B&W Tek Portable i-Raman Plus and i-Raman EX (1064 nm laser system) with BWSpec software can also be used in this application.
- Silverman, D.J., 2021. https://www.britannica.com/topic/Thanksgiving-Day (Accessed 11/21/2021).
- Brueck, H., 2017. https://www.businessinsider.com/why-thanksgiving-emergency-room-visits-spike-doctors-2017-11 (Accessed 11/21/2021).
- Villarreal-Soto, S.A. et al., 2019. Impact of fermentation conditions on the production of bioactive compounds with anticancer, anti-inflammatory and antioxidant properties in kombucha tea extracts. Process Biochemistry, 83, 44-54.
- Kombucha – Statistics & Facts, 2021. https://www.statista.com/topics/3513/kombucha/#dossierKeyfigures (Accessed 11/21/2021).
- Sreeramulu, G., 2000. Kombucha fermentation and its antimicrobial activity. J. Agric. Food Chem., 48, 2589-2594.
- Villarreal-Soto, S.A., 2018. Understanding Kombucha Tea Fermentation: A Review, Journal of Food Science, 83(3), 580-588
- Boyaci, I.H, et. al., 2013. Rapid analysis of sugar in honey by processing Raman spectrum using chemometric methods and artificial neural networks. Food Chemistry, 136(2013) 1444-1452.
This information has been sourced, reviewed and adapted from materials provided by B&W Tek.
For more information on this source, please visit B&W Tek.