Abstract: The objective of this study was to dry sweet liquid whey using
drum dryer and to utilize the whey powder in French-type bread and cookies as
a sugar substitute. The sweet whey powder was characterized chemically for ash,
moisture, water activity, protein, salt, acidity and lactose contents. Optimization
parameters including drying temperature, drum speed and starch addition for
whey drying by drum dryer were tested to produce the best powder characteristics.
The optimum temperature was 140°C at a drum speed of 20 rpm with a corn
starch level of 2% (weight per weight). Sweet whey powder produced was used
as a sugar replacer in French-type bread and butter cookies at substitution
levels of 25, 50 and 75% of total sugars. The developed products were analyzed
chemically and sensorially. The two developed products were relatively high
in protein, ash, lactose and salts compared to the control samples. Regarding
the sensory evaluation, the results showed that the sugar substitution of 25
and 50% in bread and cookies were significantly (p<0.05) better than the
control. It can be concluded that sweet whey powder can significantly improve
the quality of the studied bakery items. |