Akademik Veri Yönetim Sistemi
JOURNAL OF FOOD ENGINEERING, cilt.65, sa.3, ss.325-331, 2004 (SCI-Expanded)
Knowledge of the physical and nutritional properties of Juniperus drupacea fruit, which is used to produce pekmez (a traditional Turkish fruit concentrate), is necessary for the design of equipment for harvesting, transporting, sorting, cleaning, separating, smashing, extracting and processing it into different food. In this research, the nutritional properties of J. drupacea fruit and its concentrate were determined, and the effects of different moisture contents on the physical properties of the fruit were investigated.
J. drupacea fruit pekmez is rich in some nutritional constituents, such as sugar (34.97 g/100 g), ash (3.79 g/100 g), Ca (1499 mg/kg), P (1445 mg/kg) and Zn (12.79 mg/kg). The average dimensions of the fruits were found to be 25.18 mm in length, and 23.09 mm in diameter, with a geometric mean diameter of 23.70 mm, a volume of 6422 mm(3), a sphericity of 0.947, a surface area of 1776 mm(2), a projected area of 480 mm(2), a mass of 5.98 g, and a thousand fruit mass of 6015 g at an initial moisture of 18.9% d.b.
At moisture contents from 8.9% to 41.2% d.b., the bulk density, fruit density and porosity varied from 488.1 to 465.6 kg/m(3), from 989.3 to 991.5 kg/m(3), and from 0.507 to 0.520, respectively. The terminal velocity increased from 5.07 to 6.14 m/s with an increase in the moisture content of the fruit. The static and dynamic coefficients of friction were measured at the different moisture contents on three different surfaces, and results varied between 0.235-0.637 and 0.197-0.540, respectively. The rupture strength decreased from 692.4 to 481.4 N with an increase in the moisture content of the fruit. The average values of extraction rate and extraction yield varied from 0.75 to 1.82degreesBx/h, and from 5.5 to 14.7degreesBx/100 g, respectively. The highest values of the extraction were obtained at an initial moisture content of 18.9% d.b.