Microbial profiling of bold green tea bottled beverages: A screening experiment

Area of Science:

• Microbiology
• Food Science
• Oral Health

Background:

• Bottled tea beverages are popular for convenience.
• Direct consumption from the bottle can introduce oral bacteria.
• The safety of consuming leftover bottled tea is not well-established.

Purpose of the Study:

• To investigate the bacterial growth in bottled green tea after direct consumption.
• To assess the storage potential and drinking safety of these beverages.
• To identify predominant bacterial species and their correlation with tea composition.

Main Methods:

• Saliva samples from 14 participants were inoculated into six types of bottled green tea.
• Bottles were incubated at 37°C for 24 hours.
• Bacterial identification was performed using 16S rDNA sequencing.

Main Results:

• Over 60% of the green tea samples showed low bacterial levels (<10³ CFU/mL) after 24 hours.
• Lactobacillus species (Limosilactobacillus, Lactiplantibacillus) were detected as predominant bacteria in some samples.
• No clear correlation was found between total catechin concentration and bacterial growth inhibition.

Conclusions:

• While catechins may influence bacterial composition, they do not guarantee inhibition of growth.
• Consumption of leftover bottled green tea may carry a risk of bacterial proliferation.
• Further studies are needed to establish clear safety guidelines for opened bottled tea beverages.