Food & Nutrition

Arab Journal of Food & Nutrition
16. A Study toward the Simplification of the Californian Method for the
Production of Black Table Olives, Using Two Local Cultivars (1995)
Mahmood Khalil Mahmood Radwan\ University of Jordan
Supervisor: Mohammad Ali Humeid
Co-Supevisor: Dr. Mohammad Isam Yamani
This study aimed at investigation of the possibility of simplifying some steps of
the Californian method for the production of black table olives. The experiments were
carried out on two local cultivars namely Nabali & Rasee’i, to overcome some
difficulties related to:
- The control of initial lye treatment which facilitates the subsequent lye
treatments
- The development and fixation of olive pigments which is negatively affected by
the lye treatment.
- The elimination of residual lye from the fruits after the final lye treatment.
The results showed that treatment of the fruits with boiling water for 25 seconds
reduced the time required for final lye treatment to the half whereas the conventional
initial treatment with 2% lye reduced the final lye treatment to 1/5 as compared with
the control.
The development of the color by oxidation with oxygen gas-as a new method
proved to be superior to the conventional oxidation by aeration; 3 hours were
sufficient to develop a black color in Rasee’i, and a dark brown color in Nabali olives.
In comparison, a 12-hour aeration failed to develop the same color in both olive
varieties.
The result of the sensory evaluation showed the sensory superiority of the table
olives neutralized with carbonic acid, as compared with olive treated with citric acid or
washed successively with water to eliminate the excess alkali.
Based on the results of this study, a modified method for pickling black table
olives is outlined as follows:
Soaking the fruits in 2% caustic soda until the skin is penetrated, then exposing
the fruits to oxygen gas in closed containers for 3 hours with intermittent shaking,
followed by soaking in 1% caustic soda until 2/3 of the flesh depth is penetrated. A
second oxygen treatment is applied, then the fruits are rinsed three times with water
and transfer to 7% brine, neutralization of alkali is performed by three times
percolation with CO 2 gas every three days for 10 minutes each, finally the fruits are
stored for few months under anaerobic condition.
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Volume 22 11, No. 25, 2011