Abstract:
The present study is concerned with how to develop improved quality yogurt in terms of
texture, flavor, food value and low cost. Natural flora and traditional flavor in yogurt of
indigenous varieties have been continuously changing due to the introduction of imported
commercial starter cultures. Because of the necessity to preserve our natural starter cultures
and to increase the availability of them for industrial use, these cultures must be isolated
from artisanal yogurts, genetically characterized and investigated regarding their desirable
properties for commercial use in yogurt production. The aim of this project was to select
and isolate the better strains of Lactobacillus (starters) from the locally available yogurt
(both branded and non-branded) found in Dhaka, Bangladesh to optimize the yogurt
production with an improved quality. Total of 19 different yogurt samples were purchased
from different places for this study. Each isolated organism was used individually to
produce yogurt and later better starter cultures were selected and combined to find any new
or improved quality yogurt. Changes of pH and total titratable acidity were monitored and
the viability of probiotic bacteria was evaluated during and after refrigerated storage. One
of the most important sensorial attributes for yogurt is texture, which was assessed by
sensory analysis. Therefore, chemical, physical, microbial and organoleptic analyses for
samples were conducted at predetermined days. It was found yogurt isolates have potential
to be used in dairy industry in terms of their high technological and organoleptic
characteristics.
