Analysis of textural characteristics The viscosity for
yogurt sample was measured with an NDJ-1S viscometer
(Shanghai Fangrui Instrument Co., Ltd., Shanghai, China)
during the time of 3 min at constant speed of spindle
rotation of 20 rpm. The hardness of yogurt was determined
following the user guideline of the Stable Micro System
Mod. TA.XTPLUS (Stable Micro Systems Ltd., Godalming,
UK).