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Showing 53 results for Sadeghi

Javad Pour-Reza, Javad Mirmohammadsadeghi,
Volume 2, Issue 2 (summer 1998)
Abstract

In a completely randomized design, 600 commercial day old broiler chickens were used to study the possibility of replacing corn with barley. Each of 10 experimental diets in which corn was replaced with barley at levels of 0, 5, 10, 20 and 40 percent, with and without tallow, were given to 4 replicates of 15 chickens each. At 42, 49 and 56th days of age, one male and one female from each pen were killed. Body weight gain, feed intake and feed conversion ratio were not affected by different levels of barley at 42th day of age. Increasing the level of barley had not effect on body weight gain at 56th day of age. Feed conversion ratio improved slightly due to addition of 4% tallow to the diets containing different levels of barley. Abdominal fat was increased due to added tallow in males and females. Increasing slaughter age increased abdominal fat in both sexes. Difference in abdominal fat in females was more than males.
A.r. Sadeghi Mahounack, F. Shahidi,
Volume 5, Issue 1 (spring 2001)
Abstract

The antifungal effect of sodium diacetate on inhibiting the growth of some bread spoiling molds was examined both in culture media and in flat bread “In situ”. In the first step, the antifungal effect of different concentrations of sodium diacetate: 0, 1000, 2000, 3000, 4000, and 5000 ppm were examined against Aspergillus sp., Aspergillus niger, Rhizopus sp., and Penicillium sp.

The results indicated that as the concentration of sodium diacetate increased, the mold growth decreased. At 5000 ppm the mold growth was inhibited up to fifth day (the last day of experiment). Based on these results, the antifungal effect of different concentrations of sodium diacetate was evaluated in bread “In situ”. In this stage Aspergillus sp. was selected as the indicator mold. The results indicated that if 3000 ppm of sodium diacetate is used, not only mold growth is inhibited but bread staling can also be prevented. This concentration of sodium diacetate does not have any harmful effect on texture and flavour, and can increase bread shelf life up to four days. Higher concentrations of sodium diacetate can inhibit mold growth completely, but have negative effects on texture and flavour. Therefore, 3000 ppm of sodium diacetate is recommended for increasing bread shelf life.


M. Loghavi, A. Mollasadeghi,
Volume 6, Issue 2 (summer 2002)
Abstract

In this study tractive efficiency (TE) of MF285 and U650 tractors during moldboard plowing were evaluated and compared. Field experiments were conducted at the Experimental Station, College of Agriculture, Shiraz University, using a randomized complete block design with a 3*3 factorial. The soil was sandy clay loam with an average moisture content of 18% b.d. from zero to 30 cm depth. Test treatments were combinations of three tractor types or conditions (U650, MF285 liquid ballasted and MF285 with no liquid or weight ballast) and three levels of plowing depth (10-15 cm, 15-20 cm and 20-25 cm). Plowing speed was kept constant at about 4 km/h throughout the experiment. The measured or calculated parameters included: tractor drawbar pull and rolling resistance, drive wheel slip and tractor tractive efficiency. Statistical analysis of the test results showed that the primary difference between the tractor types or conditions was in their wheel slip, such that the average wheel slip of U650 was lowest (12.6%) while that of unballasted MF285 was highest (27%) and was reduced to 17.7% with liquid ballasting. Also, while growth of unballasted MF285 wheel slip with increasing plowing depth was drastically high (11% to 48%), that of U650 was quite moderate (9.7% to 16.5%). Analysis of the calculated values of TE showed that there was no significant changes in the TE of U650 with increasing plowing depth and that with an average of 73.8%, it had a desirable performance. The TE of unballasted MF285 that was over 75% at shallow plowing, dropped to 46% with increasing plowing depth, while water ballasting improved the decreasing trend of TE with plowing depth and raised its minimum value to about 63%. The overall results of this study showed that unballasted MF285 tractors had desirable TE only at shallow plowing and that for medium and deep plowing, U650 or water ballasted MF285 tractors should be used.
A. A. Talebi, E. Rakhshani, S. E. Sadeghi, Y. Fathipour,
Volume 6, Issue 3 (fall 2002)
Abstract

Fertility, developmental time and adult longevity of walnut aphid, Chromaphis juglandicola (Kalt.) and its parasitoid wasp, Trioxys pallidus (Hal.) were studied under controlled conditions with a constant temperature of 26±2oC, relative humidity of 60±5%, and 16:8 (L:D) photoperiod. Populations of walnut aphid and parasitoid wasp were reared on walnut seedling in a growth chamber. The mean developmental period, daily fertility rate, and progeny sex ratio were combined to construct demographic life tables. From these tables, intrinsic natural rate of increase (rm), net reproductive rate (R0) and mean generation time (Tc) were calculated. The net reproductive rate (female offsprings per female per generation) and intrinsic rate of natural increase values were 34.69 and 0.278 in walnut aphid and 53.85 and 0.385 in parasitoid, respectively. The mean generation time was 12.75 days in walnut aphid and 10.35 days in parasitoid. Values of rw (weekly multiplication of the females) indicates that T. pallidus is able to multiply 14.81 times per week, whereas the population of walnut aphid multiplies by only 7.001 times in the same period. The population of parasitoids doubled within 1.8 days while the aphid took 2.49 days. Mean pre-imaginal period was 9.14±0.34 days for male and 9.16±0.12 days for female parasitoids on a mixture of different nymphal stages of host. In walnut aphid it was 9.30±0.10 days. The pre-imaginal periods of parasitoid decreases as the aphid host ages. Longevity of adult male and female was 6.17±0.22 and 6.87±0.23 days, respectively, and 12.24±0.94 days for walnut aphid.
A. Alami, M. Taeb, A. Lotfi, Y. Sadeghian Motahar,
Volume 7, Issue 1 (spring 2003)
Abstract

Thirty genotypes of pistachio cultivars and related species were evaluated for genetic diversity using three polymorphic isozymes, i.e. Esterase, Peroxidase and Malate dehydrogenase. Young leaves of pistachio were crushed with extraction buffer containing: 20% sucrose, 0.01 M dithiothretiol, 2% polyethylene glycol, and 8% polyvenyl polypyrollidone. Samples were analyzed using isoelectric focussing on polyacrylamide gels containing 2% (W/V) ampholyte. All the three isozymes revealed high degrees of polymorphism in pistachio cultivars and related species. Maximum polymorphism was observed for Est. enzyme. A total of 19 bands in Est. and 28 bands in MDH were observed in a wide range of pH gradient however, in Per. there were 11 bands all of which located in a narrow range of pH gradient. Cluster analysis based on the three system enzymes revealed that all the 30 pistachio genotypes were in 8 main classes and 20 subclasses and the extent of genetic similarity reduced from cultivated varieties to species, which were finally classified in 3 groups. Sarakhs variety, a wild type of P. vera, was classified in a group between cultivated varieties and species.
M. Toodehroosta, J. Mir-Mohammad Sadeghi,
Volume 7, Issue 2 (summer 2003)
Abstract

The purpose of this study is to investigate the income distribution among the farmers of two districts of lowland and upland of Savojbolagh township of Tehran Province, Iran. The data of this study were collected by filling out questionnaires through interviews with 350 farmers who were selected by stratified random sampling. For analysis, such techniques as Gini Ratio, comparing the quintiles, and comparing means of different variables were used. The results showed that the income inequalities in the upland district were larger than in lowland. Income mean in the fifth quintile relative to other quintiles was considerably large and this fact was more serious in upland. As in income distribution, similar inequalities were observed in land distribution. The source of income of the farmers included income from agricultural activities (crops, livestock and fruit production) and from nonagricultural activities (second jobs and other incomes). Inequalities in total income in lowland and upland were mainly generated from agricultural sources of income while non-agricultural sources were less important. Inequalities in income from agricultural sources in lowland were related to livestock, fruits, and crops, and in upland to livestock, crops and fruits, respectively.
A. A. Barati, J. Mir Mohammad Sadeghi, A. Khatoonabadi,
Volume 8, Issue 2 (summer 2004)
Abstract

Considering the population growth and limitation of expansion in cultivation areas, employment in non-agricultural jobs in rural areas is inevitable. The purpose of this study is to investigate the factors affecting the supply of labor of the rural families on non-agricultural jobs in the rural areas. A sample of 300 families from rural areas of the Ghoochan Township in 2000-2001 was studied. The data were collected through interviews and questionnaires. The analysis used a multivariable regression equation. The results showed that: 1. The wage level of the non-agricultural experience of the person had positive effect on the supply of labors to non-agricultural jobs. 2. However, this effect was negative for the number of days the person worked on farm. Finally, since wages earned from non-agricultural jobs was higher than that of agricultural jobs. Therefore, it is suggested that for the purpose of increasing the income of rural people, non-agricultural jobs in rural areas be facilitated and encouraged
A. Zare Shahneh, H. Sadeghi Panah,
Volume 8, Issue 4 (winter 2005)
Abstract

In order to determine the effects of fetal growth rate on plasma concentrations of glucose, triglyceride, total protein, and urea in ewes, this experiment was conducted at Animal Research Station of Tehran University Agricultural College. Sixteen pregnant Varamini ewes were allocated to 4 groups (n=4). During the breeding season, ewes of group 1 were mated by Varamini ram, animals in groups 2, 3 and 4 were mated by Moghani, Afshari and Shall rams, respectively. Because of the different genetic capacities of sires, fetal growth rate was expected to be different in various groups. Ewes in all groups were fed the same ration, so it was expected that differences in fetal growth rates would affect the mobilization of maternal fat and protein storage and blood levels of their metabolites. Blood samples were collected from jugular veins of ewes during the last 8 weeks of pregnancy and first week after lambing. Plasma levels of glucose, cholestrol, and triglycerid were not different among 4 groups. Total plasma protein in ewes carrying heavier fetuses was lower than in ewes with lighter fetuses (p<0.05). Conversely, plasma urea concentrations in ewes with heavier fetuses were higher than in ewes with lighter fetuses.
M. N. Gholami-Rouchi, J. M. Sadeghi, A. Dehghani,
Volume 9, Issue 1 (spring 2005)
Abstract

This research was conducted to measure the total factor productivity (TFP) of the rural small industries in Isfahan province comprising six types of industries: food, textile, metal, non-metal mineral, chemical, and cellulose. Among the 166 rural small industries sponsored by Jihad-Agriculture Organization of Isfahan in 2001(1380), 60 plants were selected. Cross-section information collected from the 60 plants by a questionnaire in that year confirmed the body of data for this study. The distribution of the types of the 60 selected plants followed the distribution of the types in the plant population. The analytical part of this research consisted of two sections. In the first section, the TFP of the rural small industries was established by applying Cobb-Douglas production function in which the value of the plant production was the dependent variable and the investment costs, total hours of labor, costs of raw materials, and the costs of energy and water were the independent variables. Factors affecting TFP were analyzed in the second section. The estimated coefficients of the first section and the actual data of the variables, were used to calculate the TFP for each plant. Then, another regression model was worked out in which the calculated TFPs were the dependent variable. The independent variables included the mean of the number of the employees' children, the percentage of the production employees with at least primary school level of education, annual number of the off days, dummy variable for the members of the cooperative association, and a few other variables. The results of the first section showed that the TFP of food industries was higher than that of other types of industries and there was no significant difference between the TFP of textile, metal, non metal mineral, chemical and cellulose industries. The results of the analysis for determining the factors affecting the TFP, showed that the existence of a research section in the plant, the insurance of the employees and the mean of the number of employees' children had a positive effect on the TFP. But, the level of the education of the production workers, the area of the plant buildings, and the number of the days off in plant had negative effects.
M. Alikhani, A. A. Alamooti, Gh. R. Ghorbani, N. Sadeghi,
Volume 9, Issue 3 (fall 2005)
Abstract

Whole plant sunflower and sunflower without head were ensiled in plastic containers using additives in a 2×2×2×2 factorial arrangement in a completely randomized design with three replicates. Additives were molasses, urea (at 4 and 0.5 percent wet basis respectively), and a bacterial inoculant (Agros 6gr/ton of forage as manufacture’s instruction). Compared with silages without head, ensiling sunflower as whole plant resulted in lower pH, neutral detergent fiber (NDF) and ash versus higher concentrations of crude protein and ether extract (EE). No significant effect of seed was observed on lactic acid concentration and dry matter degradability (P<0.05). With the addition of molasses, the cell wall components and the EE concentrations reduced, but dry matter content increased. Highest degradability of dry matter was also observed in molasses-treated silages (average 58.04, P<0.007). With the addition of urea a significant increase was seen in CP content of either whole plant or headless silages (P<0.0001) with no effect on other fermentation characteristics. Bacterial inoculation of silages elevated the levels of lactic acid (2.81% DM) with more pronounced effect on headless than whole plant silages. Regardless of type of additives, butyric acid concentrations were ideally minimal (near to 2%) indicating least clostridial damage. The qualitative visual evaluation of the silage on the basis of scale of 1-20 for the smel, colour and structure of the silage and giving number to the mold damage on the basis of 1-10 placed all the treatment in an acceptable quality, although the mold damage was highest in silages without molasses. Results of this experiment indicated that better quality of silalges could be provided by adding molasses and ensiling whole plant sunflower. Improving quality of silages contained molasses might necesitate the additiion of a source of water-soluble carbohydrate at ensiling.
S. S. Hosseini, E. Hassanpour, S. Y. Sadeghian,
Volume 10, Issue 3 (fall 2006)
Abstract

The first Iranian hybrid monogerm cultivar of sugarbeet was developed in 2000 after an 8-year period of R&D activity. The cultivar is not only a high yielding variety but enjoys a good resistance to bolting and Sercospora. The study sought to estimate the rate of return to the public investment made to develop this variety, using the economic surplus approach. The results revealed that the investment has got an internal rate of return of 117 percent and that it has produced an exchange saving of $28.7 million. This finding indicates that the investment has been highly productive and that the field suffers underinvestment.
M. Moradi Shahrbabak, M. Sadeghi, S. R. Miraei Ashtiani, M. B. Sayadnejad,
Volume 10, Issue 3 (fall 2006)
Abstract

This research was carried out to investigate the heterogeneity of milk yield variance components in different production levels of holstein cattles. The first lactation milk yield records of 95945 Holstein cattles, which had calved in 651 herds through years 1991 to 2000, were used in this research. Data was collected by the Animal Breeding Center of Iran and adjusted for two-time milking per day. Records were classified into three classes: low (less than 5275 kg), average (5275-6874 kg), and high (more than 6874 kg) based on the level of production. Variance components and genetic parameters were estimated using single and three-trait animal models for each class and three classes with Derivative Free Restricted Maximum Likelihood methods (DF-REML). Bartlett test showed significant differences for variance components between classes. Milk yield heritability was estimated as 0.205, 0.276, and 0.196 for low, average, and high class, respectively, in both single and three-trait analysis. The gentic correlation coefficient between classes ranged from 0.80 to 0.85, Phenotypic correlation coefficients between classes were low and ranged from 0.17 to 0.19. The highest rank correlation coefficient between estimated breeding value by single and three-trait model was obtained in average class. The average changes in the rank of common animals in the top 1% of cows were greather than the top 5% of bulls. Adjustment for heterogeneity of variance components suggested selecting more top cows from herds with high level of production.
Kh. Jalili, S. H. R. Sadeghi, D. Nikkami,
Volume 10, Issue 4 (winter 2007)
Abstract

Improper management of watershed land utilization has many ill effects on the available resources. Land use optimization is one of the proper strategies to achieve sustainable development and to reduce resource dissipation. Focusing on Brimvand watershed in Kermanshah province which comprises an area of 9572 ha, the present study was conducted to find out the most suitable land allocation to different land uses viz. garden, irrigated farming, dry farming and rangeland to achieve soil erosion minimization and benefit maximization. The soil erosion, net benefit and standard land capability maps were supposed as the inputs of the objective functions and to defined constraints. The multi-objective linear problem was then solved using simplex method with the help of ADBASE software package and ultimately the optimal solution was gained. Additionally, the results of the study revealed that the amount of soil erosion could reduce by 7.78% whereas the benefit increases at the rate of 118.62%, in case of implementation of optimal solution. The above mentioned optimization led to dry farming decrease and garden increase over that area. The results of sensitivity analysis also showed that objective functions were strongly susceptible to the variation of maximum constraint of irrigated farming and garden areas.
A. Mazaheri, B. Hatami, J. Khajehali, S. E. Sadeghi,
Volume 11, Issue 41 (fall 2007)
Abstract

Sarta longhorned beetle, Aeolesthes sarta, is one of the most destructive wood borer pests of fruit and shade trees in Iran. In this research, the reproductive parameters were studied under laboratory conditions. Fifteen pairs of newly developed adults (1-2 days after emergence from overwintering sites) were caged separately on 15 logs of Ulmus carpinifolia and fertility table was made using this data. The results showed that 3.9±0.2 days after emergence, females began to oviposit for 16.6±0.6 days, as oviposition period. Mean number of laid eggs was 122.6±17.5 per female. The mean longevity of male and female was 26±0.6 and 29.4±0.4 days, respectively. Females had no mortality during oviposition period, so gross reproductive rate (GRR) and net reproductive rate (R0) (famale/female/generation) were equal (61.6±8.7). Intrinsic rate of increase (rm), mean generation time (T) and doubling time of the population (t) were 0.0067±0.24-5 famale/female/day, 612.5±0.4 and 102.7±3.6 days, respectively. The finite rate of increase (λ) (female/female/day) was 1.006±0.24-5. Intrinsic rate of increase (rm) was very low (0.00672), because of longer lifetime of females (mean 602 days), low longevity during reproductive period (maximum 22 days) and long mean generation time (612.5 days).
A. Sadeghi, F. Shahidi, S.a. Mortazavi, M. N. Mahalati, S.h.r. Beheshti,
Volume 12, Issue 43 (spring 2008)
Abstract

The aim of this study was to use Alpha-amylase termamyl 2-x for maltodextrin production from corn starch and evaluate its industrial uses. Based on the results obtained in laboratory, this process was accomplished in pilot plant scale. The process included preparation of starch suspension, pH adjustment, addition of enzyme, heating under stirring, continuous control of DE and Brix, enzyme inactivation in adequate DE, separation of soluble sections by centrifuge and finally spray-drying of the maltodextrin liquid. In this investigation, the amount of DE at dry matter was calculated under three enzyme concentrations (0.2, 0.25 and 0.3 ml of Alpha-amylase termamyl 2-x per Kg of starch) and in three different hydrolysis temperatures (60, 65 and 70 ºC) at constant pH (6). A completely randomized design with factorial arrangement and 5 replications was conducted. To study the relationship between DE and different parameters, multiple linear regression was used. Finally, for approximation of DE (based on enzyme concentrations, temperatures and hydrolysis times) a regression model was used. The results from different enzyme dosages at the same temperature and time of hydrolysis differed significantly (p≤ 0.05). Meanwhile, the best enzyme concentration and hydrolysis temperature for maltodextrin (high DE) production after 300 minutes were 0.25 ml of enzyme per kg of starch and 70 ºC, respectively. In these conditions, the least residual starch concentration and residual Alpha-amylase activity were observed.
S.h Sadeghi, S.h Pourghasemi, M Mohamadi, H Agharazi,
Volume 12, Issue 46 (fall 2009)
Abstract

The use of suitable empirical models for estimation of soil erosion and sediment yield is essential because of nonexistence or shortage of associated data in many watersheds. In the present study, the applicability of the USLE and its different versions Viz. MUSLE-S, AOF, MUSLT, MUSLE-E, USLE-M and AUSLE in estimation of storm-wise sediment yield from standard plots installed in dry farming, ploughed and rangeland treatments was evaluated. To conduct the study, the entire input data were collected from plots installed in three replicates in each treatment in Khosbijan Natural Resources Research Station in Arak Township. The models’ estimates were then compared with the observed sediment data for 12 storm events. Contrary to high correlation among different models’ estimates, the models used in estimation of measured sediment data were found inapplicable. However, significant relationship (r=94.4%) and non-significant relationship with correlation coefficients less than 50% were found between MUSLE-E, and MUSLE-S and MUSLE-E estimates and measured data in rangeland, dry farming and ploughed treatments, respectively.
S Zandsalimi, M Mosadeghi, A Mahbobi,
Volume 12, Issue 46 (1-2009)
Abstract

Organic fertilizers are the sources of many human-pathogenic microorganisms which potentially threaten the human health. This study was carried out to explore the possible effects of soil and manure types on filtration, transport and fate of manure-borne bacteria through undisturbed soil columns. The manure treatments consisted of cow manure, poultry manure and sewage sludge which were distributed at the rate of 10 Mg ha-1 on the surfaces of intact columns of two sandy clay loam and loamy sand soils. The manure-treated soil columns were leached by tap water with similar unsaturated flux of 4.8 cm h-1 up to four pore volumes (PV). The influent and leachate were sampled at different PVs. Gram-negative bacteria concentrations were determined for the influent and the columns’ leachate. Average influent concentration, average effluent concentration, relative filtration, and transported bacteria fraction during the leaching events were determined. Significant differences (P<0.05) were observed between the poultry manure and the other two manures in terms of average influent (i.e. manure-released) bacteria concentration. Stable structure and preferential pathways facilitated the bacteria movement in the sandy clay loam soil columns. The loamy sand soil strained 1.45 times more bacteria than the sandy clay loam soil due to its weak structure and blocked-dead pores. Relative contamination of the effluent was higher for poultry manure when compared with the other fertilizers. The low ionic strength of sewage sludge suspension caused the lower filtration of bacteria through the soil columns. The high concentration of soluble organics in cow manure resulted in a relative transport of the bacteria 1.12 times greater than the poultry manure. In general, management of organic fertilizers especially household poultry manure, as a considerable source of pathogenic bacteria, is important to control the environmental risks of pathogenic pollutions. Moreover, the soil texture and structure significantly affected the fate of manure-borne bacteria.
A Kochaki, A Sadeghi, F Shahidi, A Mortazavi, M Nasiri,
Volume 13, Issue 47 (4-2009)
Abstract

This study was intended to use the sourdough LAB containing specific starter cultures for Barbari bread production and reduction of its staling. For sourdough preparation, fresh microbial cells were collected by centrifugation from LAB cultures. Then 1.5% of flour (w/w) from these washed cells with the same amounts of wheat flour and tap water and 0.25% (w/w) active dry yeast extract, containing Saccharomyces cerevisiae were mixed. The effects of fermentation time (8, 16 and 24 hours), fermentation temperature (28, 32 and 36 ºC) and type of starter culture (Lactobacillus sanfransicencis, Lactobacillus plantarum and a mixture of both LAB) were analyzed in a completely randomized design with factorial experiment with 4 replications. Bread staling was determined by its measuring crumb hardness and specific volume in 1, 24, 48 and 72 hours after baking. Correlation between variables was obtained by multivariate regression, and regression models were exhibited. The results showed that sourdough had significant effect (p≤0.05) on reduction of Barbari bread staling at 1, 24, 48 and 72 hours after baking in comparison with control sample. Moreover, the sample prepared with Lactobacillus plantarum (24 h fermentation time and 32 ºC fermentation temperature) had the maximum specific volume and the least staling, 72 hours after baking.
M Jalali Hajiabadi, A Sadeghi, N Mahbobi Sofiani, M Chamani, Gh Riazi,
Volume 13, Issue 47 (4-2009)
Abstract

In order to study the effects of L-carnitine on performance and some blood biochemical parameters of rainbow trout, the present experiment was conducted with 144 fish (130±5 g) for 8 weeks. In a completely randomized design, the experimental fish were divided into 9 groups with 3 treatments and 3 replicates and 16 fish in each group. Levels of L-carnitine supplements were 0 (control), 1 and 2 g per kg of diet. Results indicated that specific growth rate (SGR), total body weight, weight gain and protein efficiency ratio (PER) were significantly increased by 1g/kg L-carnitine supplements (P<0.05). L-Carnitine also improved feed conversion ratio (FCR) of fish. Crude protein of fish fillet was increased, but its crude fat was reduced at 1g/kg L-carnitine treatment. Similarly, cholesterol, total protein, albumin and globulin of fish blood serum were significantly (P<0.05) increased by the same levels of L-carnitine in the diet, however, blood glucose level remained unchanged. L-Carnitine reduced visceral fat index and increased hepatosomatic index. In conclusion, the results of the present study indicated that the addition of 1g L-carnitine per kg of diet could improve the performance of rainbow trout at grower stage.
A Akbari, M Shahedi, N Hmadami, Sh Dokhani, M Sadeghi,
Volume 13, Issue 47 (4-2009)
Abstract

Sun drying is a well-known food preservation technique that reduces the moisture contents of agricultural products. Shrinkage, rehydration ability and color of food materials during air drying adversely affect the quality of the dried products. Since all fresh tomatoes can not be consumed at the time of harvest, preservation provides a larger market, allowing consumers to buy the preserved tomato through the year. A natural convection solar dryer consisting of a solar air heater and a drying chamber was manufactured in this research. Tomato slices were dried in the solar dryer and compared with open sun drying. Also, tomato slices were dried in a laboratory oven (operated at temperature 50, 60, 70, 80°C). With increasing the temperature, the time required to arrive certain moisture content is decreased. Also results showed that drying time in the solar dryer is shorter than open sun drying. In other words, drying time was reduced 17 to 45% by the solar drying in comparison to open – sun drying. The experimental shrinkage data showed a linear behavior with moisture content. Also, the experimental data didn't show a strong effect of temperature on the rehydration ability of the product. Thus, the effect of temperature and method of sun drying on the shrinkage phenomenon and the rehydration ability can be neglected. Tomato slices dried at 50°C had better appearance (lightness and red color) than at 80°C.

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