A. Memari; H. Shamsabadi; M. H. Rahmati; M. H. Razzaghi
Abstract
Introduction Olive is one of the plants, that has been cultivated for long in Iran. The average extracted oil is about 65 kg per tree. Four to five kg olives give approximately one liter oil. Olive harvesting problem, is one of the obstacles to development cultivation in Golestan province. Concurrency ...
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Introduction Olive is one of the plants, that has been cultivated for long in Iran. The average extracted oil is about 65 kg per tree. Four to five kg olives give approximately one liter oil. Olive harvesting problem, is one of the obstacles to development cultivation in Golestan province. Concurrency olive harvesting time with a number of field crops, seasonal precipitation and a lack of the workers are some limitations for development of this fields. Investigative study of the alternative methods instead of the traditional can be desirable strategy for cultivation development of this product. But gardeners are not eager to use this equipment due to lack of harvesting machine. With regard to the afore-mentioned items, the objective of this study was to determine the appropriate method, the optimal time and interaction effect of the two afore-mentioned factors on the measured traits in order to damage reduction during harvesting time. Materials and Methods This research was conducted with the two factors, i) date of harvesting and ii) harvesting method. In this regard, harvesting operation carried out at the three dates including; i) 19 December, ii) 3 January and iii) 18 January in 2015. At the three afore-mentioned harvesting dates; olives were harvested with the three methods including; i) traditional (hitting with the long wood by worker), ii) manual comb and iii) motorize pneumatic comb shaker. The measured traits during operations before and during the harvesting time were the abscission naturally percentage, at the start and the end of the harvest, amount of harvesting (harvested fruit percentage), the remaining fruits percentage on the tree, damaged fruits percentage and damaged fruit index. The experimental design carried out in this research was a split plot based on the randomized complete block design, with three replications. The main plots attributed to olive harvesting time at three levels. The sub-plots attributed to types of olive harvesting method at three levels. After sampling and data collection, the data were set in the Excel software. The obtained data analyzed by using SAS software. Analysis of variance (ANOVA) and comparison of means extracted from the output of analysis of the data with a probability level of 5%. Results and Discussion Interaction effect of harvesting time and harvesting method on maturity index was significant at 1% level (Table 1). The lowest and highest value of maturity index occurred at the time of 19 December and 18 January (2.28 and 4.07), respectively. The effect of harvesting time on naturally abscission percent was significant at the 5% level. The lowest (1.16) and highest (2.21) naturally abscission attributed at the time of 18 December and 18 January, respectively. The effect of harvesting method on the percentage of the remaining fruits on the tree was significant at the 1% level. The lowest (2.71%) and the highest (5.89 %) value of the remaining fruits occurred in the manually comb and traditional methods, respectively. The effect of harvesting method on the amount of remaining fruit on the tree per kg of harvesting was significant at the 1% level. The highest (62.86 gr) and the lowest (27.92 gr) value of this trait yielded in the traditional and manually methods, respectively. Interaction effect of the harvesting time × harvesting method on the damaged fruits was significant at 1% level. The highest and the lowest values of the damaged fruits took place in 19 December and in the traditional and the manual comb methods, respectively. The effect of harvesting time on abscission leaf percent was significant at the 1% level. The highest value of 13.2% and the lowest value of 4.47% occurred in 18 January and 19 December, respectively. Interaction effect of harvesting time and harvesting method on the damaged fruits index, was significant at the 1% level in 18 January. The highest (1.002) and the lowest (0.424) yielded in traditional and manually comb methods, respectively. Conclusion The results showed that in order to percentage of remaining fruits on the tree, remaining amount on the tree per kg, damaged fruit and damaging fruit index, the best method of olive harvesting is the manually comb method. The lowest percentage of leaves abscission naturally occurred on 19 December. The Lowest percentage of leaf abscission was on 18 January. So the best of olive harvesting method (variety Koroneiky) in the study area, the use of manual comb with maturity index 3.58 is suggested.
H. Kargarpour; T. Tavakoli Hashjin; A. Hemmat; B. Ghobadian
Abstract
Introduction The olive fruit (Olea europaea L.) is so sensitive to impact like many other crops that would lead to mechanical damage and bruising which reduce the quality of it. The olive fruit damage includes a brownish bruise at the bruised location. Most mechanical impact damage occurs during harvesting, ...
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Introduction The olive fruit (Olea europaea L.) is so sensitive to impact like many other crops that would lead to mechanical damage and bruising which reduce the quality of it. The olive fruit damage includes a brownish bruise at the bruised location. Most mechanical impact damage occurs during harvesting, handling and transportation. Bruise sensitivity of two common olive cultivars in Iran (cv. Roghani and cv. Conservolea) was studied by free fall method because of development of the area under olive cultivation in Iran, and necessity to mechanical harvest in near future. Materials and Methods Two cultivar of olive fruit named Conservolea and Roghani were collected from Research Orchard of Horticultural Department of Isfahan University of Technology. A free-fall device was designed and built to accomplish an impact experiment which included a load cell monitoring system to measure impact force. The effect of cultivar, height and mass were studied in a factorial experiment. The factors consisted of two cultivar, height at five levels, and mass at three levels with 10 replications. The experiments were performed according to completely randomized design. The effect of impact force and absorbed energy was also studied for the two cultivars. The dimensions of bruising was measured 24 hours after the tests by a caliper with an accuracy of 0.01 mm. The bruising area and volume was calculated assuming the elliptical model for the bruised region. Experimental data were subjected to analysis of variance (ANOVA). Mean comparison was performed based on least significant difference (LSD) test with. Results and Discussion For both cultivars the bruising occurred under the skin and near to the stone. This could show the effect of stone at bruising. The shape of bruised region was elliptical in cv. Roghani and spherical in cv. Conservolea. The bigger stone index and the lower flesh width of cv. Roghani might be one of the reasons of more volume of bruising in this cultivar. This variety could be due to less sphericity in cv. Roghani than cv. Conservolea. The distribution of bruising was more in Roghani cultivar since it had more oil and less water content that might led to more bruising distributed under impact condition so the volume of bruising was more than Conservolea cultivar. The effects of cultivar, height and mass were significant on area and volume of bruising. Increasing height and mass significantly resulted to increase the area and volume of bruising for both cultivars. The bruise area and volume were significantly higher in cv. Roghani. This could be due to differences in physical properties of the cultivars. Roghani cultivar had a higher pit/flesh ratio in comparison with Conservolea cultivars that could contribute to more area of bruising in this cultivar. Increasing the force and energy led to increase in bruise volume for both cultivars. In cv. Roghani, despite the lower levels of force and energy, the bruise volume was more than cv. Conservolea. The reason of lower energy and force in cv. Roghani might be as a result of lower mass than cv. Conservolea. Conclusion The results showed that the effects of independent variables were significant on the volume and area of bruising so that, increasing height and mass increased the volume and area of bruising. The Roghani cv. was significantly more sensitive to bruising compared to Conservolea cv. The energy and force levels were higher in cv. Conservolea since it was heavier than cv. Roghani while the volume of the bruise was more in cv. Roghani. This might be due to the lower sphericity and flesh/pit ratio in cv. Roghani. The shape of mechanical damage which was appeared with a brownish bruising on olive tissue was related to the geometric shape of the fruit i.e. for cv. Roghani and cv. Conservolea the bruising was elliptical in and spherical just like the geometric shape of the cultivars.
A. Rezaei; M. Loghavi; S. Kamgar; Y. Mehdipour
Abstract
Introduction
Olive (Oleo europaea) includes about 20 species of small trees from Oleaceae family. This point should be considered that Iran has allocated only a small universal market to its olive products in spite of having high production potentials; so that about 23 provinces of this country can ...
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Introduction
Olive (Oleo europaea) includes about 20 species of small trees from Oleaceae family. This point should be considered that Iran has allocated only a small universal market to its olive products in spite of having high production potentials; so that about 23 provinces of this country can produce olive products. Therefore mechanizing of olive production and encouraging to develop olive trade are among the effective methods for development of this market. On the basis of IOOC report, the production of olive oil in 2008-2009 in Iran and all over the world has been 3 and 2866.5 thousand tons, respectively. Currently, harvesting olive product is done by hand in Iran. The expensiveness of work force and providing the needed workers are considered as the biggest problem in olive harvesting. While harvesting the tall trees, the workers use beating method by wood sticks which causes the fruits to be damaged and their quality to be decreased. The harvesting method which the quality and quantity of the olive final products is under its effect and also high expenses of harvesting by hand are considered as the two important factors in developing the mechanical harvesting of olive. For this purpose, the mechanized harvesting of olive should be considered for producing olive conserve and olive oil and decreasing expenses of harvesting. Considering the conducted studies on one hand and shortage of informational resources in the country on the other hand, a research was designed and performed with the following purposes:
Designing and fabricating of a portable pneumatic branch shaking system.
Determining the best frequency and oscillation duration for harvesting olive by the constructed system.
Materials and Methods
The branch shaking system is made of two general parts:
(a) The set of branch shaker driving unit.
(b) The portable vibration arm.
For constructing the set of vibrating arm, two experiments “elasticity and inflectionˮ of tree branches were conducted and the maximum force of 362.40 N was registered and it was considered as the base of computations. Then a double-action pneumatic jack with the internal diameter of 32 mm and the rod diameter of 12mm with the stroke length of 200 mm was selected. An electronic circuit was designed and developed for ordering the solenoid valve to control the flow. The system was transferred to one of the olive garden’s located in kilometer 5 of Sarvestan – Fasa road in Fars province in order to be evaluated. The effects of three oscillation frequencies of 12, 16 and 20 Hz and three oscillation durations of 5, 10 and 15 seconds at constant amplitude of 5 cm on detachment percentage of olive fruit was investigated through a factorial 3×3 experiment based on completely randomized design with four replications. Then the most suitable frequency and vibration duration was selected for harvesting olive by this system.
For measuring the static detachment force of the fruits, a tensile force dynamometer system model FG-5100 made by Lutron Company was used with the accuracy of 0.1 N and a maximum capacity of 980 N.
Results and Discussion
The variance analysis of the investigated features on the basis of the factorial experiment based on completely randomized designs was conducted through using SPSS software. The results showed that both frequency of vibration and oscillation duration had significant effect on the shaker performance; with no significant interaction effects which implies the independence of the debated variables. Comparing the means by using Duncan test at 1% significance level for features of oscillation frequency and duration of shaking showed that at any constant duration of oscillation, increasing of oscillation frequency significantly increases the percentage of the olive fruit detachment. This increase is due to the increase of dynamic force with the second power of oscillation frequency compared to the static separating force (Murphy, 1950).
It was observed that the calculated dynamic force is larger than the static force for separating the fruit in frequencies of 16 and 20 Hz, but since the dynamic force is variable at each point of the branch, 84.50 percent of fruits are separated from branches at frequency of 16 Hz and 87.25 percent of the fruits are separated from branches at frequency of 20 Hz.
Conclusions
At the end, the frequency of 20 Hz with 5 second duration of oscillation was selected as the most suitable treatment for this branch– shaker in harvesting oil-type olives.
