Assessment of Microbial Load in Made Tea and Antimicrobial Property of Made Tea Infusion

  • Md Mozammel Hoque Department of Food Engineering and Tea Technology, Shahjalal University of Science and Technology, Sylhet-3114, Bangladesh
Keywords: Antimicrobial activity - Microbial load - Peptone solution - Tea liquor - Tea.


IntroductionThis study aimed to find out that a cup of tea is or is not safe for human health from microbial contamination and to point out the antimicrobial property of made tea liquor.MethodsDifferent made tea brands were collected randomly from different super shop of Dhaka city. The Association of Official Agricultural Chemists (AOAC), 2005 was used as official methods of analysis. The Standard Plate Count (SPC) technique was used for total microbial load, yeast and fungal count. Most Probable Number (MPN) technique was used for the enumeration of coliform in tea samples.ResultsBacteria, yeast, mould and coliform were observed before and after boiling in all studied the samples. Before boiling, total microbial load and coliform were found at significantly higher of its’ acceptable limit (p<0.05) whereas yeast and fungus were found of its’ acceptable limit (p>0.05). After boiling, only coliform was observed significantly higher in all except Tetley tea at its’ non-acceptable limit (p<0.05). Fecal coliform was not present at every stage of this study. Made tea liquor has shown to have antimicrobial property.ConclusionsBoiling in tea preparation and its’ liquor antimicrobial property considerably reduced the level of microbial load to safe level for public consumption. 


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