| Summary: | The study aimes to determine the effect of different drying temperature and albumen level on
the quality of powdered yoghurt probiotic produced by foam-mat drying method. Yoghurt
was produced by 5% Streptococcus thermophilus and Lactobacillus bulgaricus starter with
ratio 1:1, and added 2% Lactobacillus casei as probiotic. The drying temperature of yoghurt
was 50, 60, and 70ºC, whereas the level of albumen was 0, 10, and 15%. The analyzed of
powder yoghurt quality include: 1) microbiological quality (total of lactic acid bacteria and
probiotic), 2) chemical quality (protein, moisture, pH, and acidity), and 3) physical quality
(solubilty). The data of yoghurt quality was analyzed statistically by two way ANOVA 3x3.
The results showed that total lactic acid bacteria (LAB) and probiotic of powdered yogurt
with drying temperature of 70o
C were lower (P<0.05) than temperature 60 and 50o
C, whereas
the level of albumen had no effect on microbiological quality. Drying temperature of 70o
C
could decrease the total lactic acid bacteria (LAB) and probiotic, moisture content, solubility
and increase the pH of powdered yoghurt. The level of albumen had no effect on moisture
content, solubility, acidity, and pH, but could affect significantly on the protein content of
powdered yoghurt. In conclusion, powdered yoghurt probiotic should be produced by drying
temperature of 60o
C and 10% albumen level.
Keywords: Yoghurt powder quality, Probiotic, Foam-mat drying, Albumen.
|
|---|