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IJSTR >> Volume 5 - Issue 1, January 2016 Edition

International Journal of Scientific & Technology Research  
International Journal of Scientific & Technology Research

Website: http://www.ijstr.org

ISSN 2277-8616

Physico-Chemical And Microbiological Quality Of Some Consumer Preferred Plain Set Yoghurts Sold In Matara Municipal Area Of Sri Lanka

[Full Text]



K.K.G.U Hemamali, V.S Jayamanne, S.M. Amarathunge



consumer preference, international standards, local standards, microbiological parameters, physico-chemical parameters, plain set yoghurt, storage period.



As yoghurt is a health food, assessment of quality of commercialized yoghurt during storage period in refrigerator is needed. Lack of data on quality parameters of yoghurt brands in Sri Lanka is impediment to consumer health. This study is an attempt to fill that gap by providing data on evaluation of the changes of physico-chemical and microbiological parameters of some plain set yoghurt sold in Matara municipal area of Sri Lanka. Five different brands of plain set yoghurt samples were collected on the basis of consumer preference for the present study. From each brand, fifteen samples were analyzed by means of their physico-chemical (syneresis effect, pH, titratable acidity, total protein content) and microbiological composition (total plate count, total yeast and mould count) by using three replicates of each sample at 4, 7, 14, 21 and 28 days intervals from production date under refrigerated condition (4 C) and compared against local and international standards. All microbiological parameters and total protein content of all plain set yoghurt brands were not within the permissible range for local and international standards. Titratable acidity was only in the permissible range of local standards. All the physico-chemical parameters and microbiological parameters of collected samples were significantly affected by storage period. Good quality yoghurt of physico-chemical and microbiological parameters with hygiene conditions during processing and storage should be encouraged for consumption.



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