lower extent. They added also that, the counts of all The acidity contents as well as pH values (Table strains, without any exception, were significantly 3) did not significantly influenced by the kind of the increased as the fortification level was raised. Further, bacterial starter used but the acid production was it is worthy to mention that, each bacterial count of increasingly promoted when the GABA level in all yoghurt treatments, in relation to the GABA bioyoghurt was 150 mg/kg. Moreover, gradual fortification level, whether when fresh or along cold increment in the acidity content and hens decrement storage period, stilled conforming the figures in the pH value were associated with the cold storage provided by Codex Alimentarius Commission of period prolonging (Table 3). Fayed et al., (2012a) FAO/WHO (2002) which approved an international found that, the GABA containing yoghurt exhibited standard as established a minimum of 107cells/g for higher TA% and hence lower pH value versus those of the starter cultures of fermented milks and a the control. These results trends are in harmony with minimum of 106cells/g for specific starter bacteria for those of LAB count mentioned before in Table (2). The which a claim is made for specific microorganism that increasing of the fortification level with GABA was has been added as supplement. associated with TA% increment and consequently low pH value. 3.3. Titratable acidity% and pH value Table (2): Population of some strains of lactic acid bacteria (log count cfu/g) of bioyoghurt (ABT-2) as affected by the fortification level with gamma amino butyric acid (GABA) during cold storage period the ordinary versus yoghurt (YC-XII) as a control. ND: Not determined The means with the same did not significantly differ (P>0.05). 3.4. Carbonyl components:
lower extent. They added also that, the counts of all strains, without any exception, were significantly increased as the fortification level was raised. Further, it is worthy to mention that, each bacterial count of all yoghurt treatments, in relation to the GABA fortification level, whether when fresh or along cold storage period, stilled conforming the figures provided by Codex Alimentarius Commission of FAO/WHO (2002) which approved an international standard as established a minimum of 107cells/g for the starter cultures of fermented milks and a minimum of 106cells/g for specific starter bacteria for which a claim is made for specific microorganism that has been added as supplement. 3.3. Titratable acidity% and pH value The acidity contents as well as pH values (Table 3) did not significantly influenced by the kind of the bacterial starter used but the acid production was increasingly promoted when the GABA level in bioyoghurt was 150 mg/kg. Moreover, gradual increment in the acidity content and hens decrement in the pH value were associated with the cold storage period prolonging (Table 3). Fayed et al., (2012a) found that, the GABA containing yoghurt exhibited higher TA% and hence lower pH value versus those of the control. These results trends are in harmony with those of LAB count mentioned before in Table (2). The increasing of the fortification level with GABA was associated with TA% increment and consequently low pH value. Table (2): Population of some strains of lactic acid bacteria (log count cfu/g) of bioyoghurt (ABT-2) as affected by the fortification level with gamma amino butyric acid (GABA) during cold storage period versus the ordinary yoghurt (YC-XII) as a control. ND: Not determined The means with the same did not significantly differ (P>0.05). 3.4. Carbonyl components: