Abstract:
Seeds from two varieties of mahlab, black and white mahlab
were obtained from the local market Khartoum North,
Khartoum State. They were then subjected to different tests
for chemical analysis, and the extracted oil was subjected to
various tests for physico-chemical analysis according to the
standard methods.
Hundred seed weights of the two mahlab varieties were
found to be (1.88g) , (4.13g) in black and white mahlab,
moisture content (6.03%), (6.22%), ash content (2.81%),
(2.12%) , protein (12%) , (28%) , (fiber 2.5%) , (1.87%) , oil
content was found to be 13.15%, 30.95% in black and white
mahlab seeds respectively. Saponification values in the two
varieties were varied from 184.23 in white mahlab to 180.3
in black mahlab. Refractive index was found to be (1.4700),
(1.4975), Specific Gravity (0.8167), (0.8511), free fatty acids (3.65%),
(3.93%), acid value (7.30), (7.86) mg KOH/g, peroxide value (4.43),
(2.54) meq O2 / Kg oil and Unsaponifiable matter (0.66%), (0.92%) in black
and white mahlab oil respectively. The major fatty acids were
found to be Palmitic (4.5%), Stearic (16.0%), Oleic (48.3%) and
Linoleic (31.6%) in black mahlab oil, while in white mahlab oil
was found to be as follows
palmitic (5.7%), oleic (46%), and
linoleic acid (48%).
Protein content was found to be 21 and 28% in black and
white seeds respectively. The total amounts of amino acids
VII
were found to be 12.55 and 18.38 g / 16 g N in black and
white seeds respectively. The percentage of essential amino
acids in black mahlab seeds was 39.5% and in white mahlab
seeds was 40.5%.
From the sensory evaluation analysis of the two mahlab oils, the results
revealed that there was a significant difference (P≤0.05) between the average
scores for color, odor and taste of the two mahlab oils and that white mahlab
oil seemed to be more acceptable compared to the black mahlab oil by
panelists.
