Characterization and Antioxidant Property of Probiotic and Synbiotic Yogurts

The effect of a prebiotic (fructooligosaccharides)
or a synbiotic components (prebiotic and probiotic)
on the viability, proteolysis and antioxidant properties of
probiotic and synbiotic yogurt during 28 days of storage at
4 �C has been investigated. Yogurt starters in conjunction
with either probiotic bacteria Lactobacillus plantarum CFR
2194, Lactobacillus fermentum CFR 2192 and/or fructooligosaccharides
(FOS) were used for yogurt preparation.
Titratable acidity and pH of all yogurt samples followed a
similar pattern of increase or decrease during storage.
Proteolysis in synbiotic yogurts was found to be significantly
(P\0.05) higher in comparison with that of control.
The addition of prebiotics had no effect
(P = 0.17888) on the viability of yogurt starters during
cold storage. No observable changes in the viability of
probiotic cultures in probiotic groups. However, supplementation
of FOS affected the growth significantly
(P\0.05) in promoting the growth of L. plantarum and L.
fermentum. Antioxidant activities, the index of nutritional
value of yogurt, were monitored. Results showed that the
DPPH-radical-scavenging activity (85 %) in synbiotic
yogurt containing L. plantarum and FOS was significantly
higher (P\0.05) in comparison with that of control yogurt
(72 %). Total phenolics and the ferric reducing power were
highest in synbiotic yogurts in comparison with that of
other test samples during the entire period of storage.
Addition of selected probiotics with FOS thus resulted in
an improved functionality of yogurt.