Chemical and Antioxidant Properties of Rayeb Milk Fortified with Thyme and Almond Oils,

The effect of fortification of Rayeb milk quality with thyme and almond oils was investigated. Control
Rayeb milk was made using Leuconostoc cremoris and Streptococcus lactis subsp. diaceteylactis culture.
Eight Rayeb milk treatments were made fortified with 0.1%, 0.2%, 0.3% and 0.4% thyme and almond oils.
Changes in chemical, antioxidant, viability of bacteria and organoleptic properties of Rayeb milk were
monitored during storage at 4º±1 for 7 days. The data indicated that essential oils had a slight effect on the
total solids and fat %. The values of acidity showed significant (P< 0.05) increase and decrease in pH were
noticed in Rayeb milk samples during storage at 4º±1 for 7 days. Total free fatty acids content increased as
increasing essential oil ratios in all treated samples. All samples exhibited good radical scavenging activity
with varied degrees, However the highest values were shown with almond oil samples on the first day. The
greatest antioxidant capacity was found in Rayeb milk samples enhanced with essential oils, as indicated by
a significant increase (P<0.05) in total flavonoids (TF), total phenolic and (DPPH) radical scavenging.
Meanwhile, the addition of essential oils improved the viability of lactic acid bacteria (LAB). The treated
samples fortified with 0.1% and 0.2% of essential oil and the control of Rayeb milk gained the highest
score for organoleptic properties.