Differentiation of organic and conventional memecik type green olives by picture forming methods and evaluation of their quality differences

The aim of this study is to evaluate the quality differences with physical and chemical analyses of the conventionally and organically cultivated Memecik type green olives and differentiation of these olives by using picture forming methods (circular and rising paper chromatography). Average olive weight (org.: 4.80 g, conv.: 5.86 g), average olive length (org.: 24.89 mm, conv.: 26.52 mm) and the ratio of flesh (org.: %78.09, conv.: %79.28) in organic olives at a lower level compared to the results obtained conventional olives and statistically significant differences were found between two groups (p<0.05). There was no significant difference between the width of the olive and flesh /seed ratios. The total dry matter (org.: %31.68, conv.: %38.67) and pH values (org.: 5.02, conv.: 5.23) of organic olives were measured lower than the conventional olives, titratable acidity (org.: %0.47, conv.: %0.37) and oleuropein values (org.: 2.65 abs, conv.: 2.41 abs) were measured higher than conventional ones (p<0.05). Total sugar (org.: %13.52, conv.: %5.74), total protein (org.: %6.35, conv.: %4.78), fat (org.: %49.78, conv.: %41.50), ash (org.: %3.94, conv.: %3.67) and total phenolic contents (org.: %259.19 mg GAE, conv.: %211.37 mg GAE) on dry matter basis is found the higher in organic olives (p<0.05). When the results of the colour parameters were evaluated, L*, b*/a* and H° values in organic olives, a*and a*/b* values in conventional olives were measured at significantly higher levels (p<0.05). There were no significant difference C values and b* values between organically and conventionally cultivation methods. Circular and rising chromatography methods were used to determine differences between organic and conventional olives. In circular chromatography method, %10 and %20 organic sample concentrations, % 20 and % 30 conventional sample concentrations with all AgNO3 concentrations (%0.25, %0.5, %0.75, %1) were determined as suitable concentrations. Differences were determined according to vivid colours and shape, depth and width of curled occurrence. In rising chromatography method, %20, %30 and %40 sample concentrations were determined as the suitable concentrations for both organic and conventional olives. The concentrations of binary AgNO3 and FeSO4 were determined as %0.25, %0.5 and %0.75 for conventional samples, %0.25 and %1 for organic samples. Differences were determined according to regional colour differences, vivid colour occurrence, width and frequency of bowl occurrence, thin line and picks at drop zone.