SOME CHEMICAL, PHYSICAL AND PHYSIO-MECHANICAL QUALITY PROPERTIES OF COLD-ADAPTED PROMISING WALNUT GENOTYPES: TURKEY, BINGOL REGION

Özet

The objective of the present study was to examine some physical and chemical shell and kernel attributes of promising walnut genotypes selected from the Bingol province in Turkey. Bingol province possesses a rich walnut population almost all of which are seedling-grown. Shell cracking resistance, kernel firmness, kernel percentage, pellicle and cotyledon color, total oil ratio, total phenol content, and antioxidant capacity as DPPH were analyzed and evaluated. Shell cracking resistance ranged from 8.73 to 34.83 kgf with an average value of 17.96 kgf. Kernel firmness was found to range from 0.87 to 1.34 kgf. Lightness (L*) of pellicle was in the range of 47.06 and 63.01 while yellowness (b*) in the range of 25.02 and 31.98. Lightness (L*) of cotyledon changed mildly from 70.76 to 76.47 with a mean of 73.57 while cotyledon yellowness was in the range of 25.49 and 30.34. The total oil ratiowas found to vary between 45.04 and 56.88%. Total phenol content was in the range of 80.97 and 142.91mg.$kg^{-1}$ with an average value of 118.12 mg.$kg^{-1}$. The DPPH free radical scavenging capacity of the genotypes vaguely varied from 64.14 to 70.52% with a mean of 69.04%. Finding especially shell cracking index, kernel percentage, and pellicle color may contribute to walnut improvement programs.