Cabinet Dryer Research Articles

Environmentally friendly technology for the production of powder for the food industry by drying the technically ripe fruits of the caper plant

The paper describes the innovative technology for the production of powder for the food industry by means of drying ripe fruits. It is shown that drying methods have a significant effect on the composition of the fruit when dried. Experiments have shown that the composition of the fruit changes when dried in the shade, and that these parameters do not change only when dried by lyophilization. The authors show that the composition of the fruit changes due to the high temperature in the cabinet dryer.

Electrostatic-Maillard formation of coconut protein Concentrate-Pectin conjugate for Oil-in-Water Emulsion: Effects of Ratio, Temperature, and pH

Polysaccharide protein conjugate is usually prepared by electrostatic interactions or Maillard reaction. In this study, coconut protein concentrate (CPC)-pectin conjugate was synthesized by a combination between the electrostatic and early stage Maillard reaction. The objective was to evaluate the effect of CPC-pectin ratio, temperature, and pH on emulsion stability index (ESI) and emulsion activity index (EAI). Furthermore, the obtained conjugate was used to stabilize the red palm oil emulsion. The conjugate was prepared by mixing CPC and pectin solution, and dried in a cabinet dryer. Factors, such as CPC-pectin ratio (1:3, 1:2, 1:1, 2:1, 3:1), incubation temperature (50, 60, 70, 80, 90 °C), and pH (3; 3.5; 4; 4.5; 5) were evaluated. The result show that CPC contained 67.40% ± 0.93 protein. ESI and EAI of CPC was not detected. CPC-pectin ratio, temperature, and pH had a significant effect on ESI and EAI, except temperature was not significant effect on EAI. Early stage Maillard reaction was confirmed by FTIR analysis since the peak intensity of amida I increased and amida II decreased. The best CPC-pectin conjugate was found at CPC-pectin ratio of 1:2 (w/w), incubation temperature of 80 °C, and pH of 4. ESI, EAI, droplet size and zeta potential of red palm oil emulsion were 165.263 min; 72.314 m 2 /g; 553.4 nm and −45.5 mV, respectively. The emulsion droplets were uniform in size and equally dispersed. In summary, drying of conjugate on cabinet dryer induced early stage Maillard reaction and the conjugate can be used to stabilize red palm oil emulsion.

Effect of Various Drying Temperatures on Characteristics of Mustard Green Flour and Leaves During Drying

Vegetables can be extended their shelf life by processing them into vegetable flour. Flour processing technology is inseparable from the drying process which means removing water from a material until it reaches a certain moisture content. This study aims to determine the effect of various temperatures at various stages of drying on the characteristics of the material to become mustard green flour. Drying it using a cabinet dryer at temperatures of 45 oC, 55 oC, and 65 oC. Observations were made at 0 h of drying (analysis of raw materials), 2 h, 4 h, and after turning into mustard green flour. The results showed that the drying temperature had an effect on the changes in the characteristics of the material during the drying process until it turned into mustard green flour. During the drying process, there was a decrease in moisture content, ash content, total chlorophyll, and physical color of the mustard green flour. Drying temperature has an effect on decreasing moisture content, ash content, total chlorophyll and physical color of mustard green flour, while drying time affects total chlorophyll and physical color of mustard green flour.

Standardization of blanching and sulphitation technique on physico-chemical parameters for dehydration of banana pseudo stem central core for powder making using cabinet dryer

Standardization of blanching and sulphitation technique on physico-chemical parameters for dehydration of banana pseudo stem central core for powder making using cabinet dryer

Deflectors as the performance booster component in designing a side-ventilated heat pump cabinet dryer for vegetables

Unbalanced drying air and temperature distribution in a dryer is among the major cause of non-uniformity in moisture content of dried food. Thus, the distribution of air and temperature in corner-ended, corner-ended with deflector, curved-ended, and curved-ended with defectors were investigated. Velocities used were 2 m/s, 4 m/s, and 6 m/s while temperatures ranged from 40-60?C. The design with lowest deviations in simulated and actual drying parameters was fabricated to dry mushrooms. Results showed that adding deflectors improved drying air and temperature distribution. The corner-ended with deflector dryer configuration was superior to other designs, with 6 m/s and 60?C being optimal. A mass transfer simulation of the corner-ended with deflectors configuration had moisture evaporate from 1.00-0.11 in 2000 seconds. A comparison of moisture ratios in the two dryers gave R? = 0.9965, which was acceptable. Drying at 55-60?C gave the best Lentinan content and rehydration ratio for mushrooms.

Macronutrient Profile of Analog Rice Based on Cornstarch, Modified Cassava Flour, and Suweg Flour

Analog rice is a food diversification product made from raw materials of various flours as an alternative to paddy rice which is produced from tubers and cereals which have a chemical content similar to rice. Cornstarch, modified cassava flour (Manihot esculenta), and suweg flour were chosen as the ingredients of analog rice due to the macronutrient content of carbohydrates, protein, fat which expect might improve the nutritional content of the analog rice. The aim of this study was to determine the macronutrient levels of analog rice of cornstarch, mocaf, and suweg flour. Research stages: the production of analog rice using formula cornflour:mocaf 1:1 and the addition of suweg flour of 0%, 5%, 10%, 15% and 20%. Then the ingridients was mixed with water and stirring. Preconditioning processed were done by steaming for 5 minutes at 90 oC. Therefore the formula were shaping manually in order to produce rice grains. The analog rice were drying in a cabinet dryer for 5 hours at 60°C. The chemical analysis, among starch content, amylose content, amylopectin content, protein content and lipid content using AOAC 2003.06-2006. The results of the this study showed that the analog rice based on cornstarch, mocaf, and the addition of suweg flour had starch content range from 82.06 to 84.06%, amylose content ranged from 26.91 to 28.53, amylopectin content ranged from 54.37 to 56.12%, protein content ranged from 0. .46 to 1.25%, and lipid content ranged from 0.02 to 0.43%. The result concluding that the higher addition of suweg flour on rice analog might increase the starch, amylopectine, protein and fat content while decrease the amylose content. Therefore, cornstarch, modified cassava flour and suweg flour are potentially used as analog rice raw materials.

Qualitative and Quantitative Analysis of Phytochemical Constituents of Alternanthera brasiliana (L.) Kuntze and Cassia alata (L.) using Different Organic Solvents

The therapeutic qualities of Alternanthera brasiliana and Cassia alata are due to the phytochemicals contained in these plants. This research was conducted to study the phytochemical analysis of leaf extracts of these plants using methanol, hexane, and chloroform solvents. The leaves were collected, cleaned, and dried for eight hours at 60°C in a cabinet dryer. Using the solvent extraction method, the extract was made. Qualitative and quantitative analysis was done to determine the occurrence of flavonoids, terpenoids, tannins, phenols, amino acids, alkaloids, phlobatannins, glycosides, and saponins. The extraction yields in methanol, hexane, and chloroform were 15.77%, 3.01%, and 3.16% for A. brasiliana and 26.91%, 19.5%, and 18.32% for C. alata. Alkaloids, terpenoids, tannins, phenols, glycosides, flavonoids, carbohydrates, phlorotannins, and saponins were all found in A. brasiliana. Alkaloids, tannins, phenols, glycosides, flavonoids, carbohydrates, and saponins were found in C. alata. Total phenolic, flavonoid, and tannin content in methanol extract for A. brasiliana were found to be 127.76 mg GAE/g, 136.48 mg GAE/g, and 58.88 mg GAE/g. The total phenolic, flavonoid and tannin content found were 41.76 mg GAE/g, 103.21 mg GAE/g, and 58.67 mg GAE in hexane extract. Similarly, 102.4 mg GAE/g, 112.49 mg GAE/g, and 41.76 mg GAE/g in the chloroform extract. Total phenolic, flavonoid, and tannin content of C. alata in the methanol extract were 36.3 mg GAE/g, 22.43 mg GAE/g, and 10.89 mg GAE/g, in the hexane extract, 25.98 mg GAE/g, 16.68 mg GAE/g, and 3.25 mg GAE/g, in the chloroform extract, 28.52 mg GAE/g, 20.33 mg GAE/g, and 4.56 mg GAE/g. From extraction yields and qualitative and quantitative analysis, methanol was the best solvent.

Phytochemical Screening of Ethnomedicinal Herbal Extracts and their Effect on Microbial Quality of Sukuti

The effect of herbal extracts of four ethnomedicinal herbs (Zanthoxylumarmatum, Litsea cubeba, Heracleum nepalense, and Evodia fraxinifolia) of culinary importance on the microbial quality of sukuti (a traditional dried meat product) was studied. Herbal extracts were prepared by grinding each herb to particle size < 250 μm, extracting in 50% (v/v) ethanol, and concentrating in a rotary vacuum evaporator at 50oC. Four of the spoilage and pathogenic microorganisms, viz., Salmonella, Staphylococcus, E. coli, and Lactobacillus were isolated from market sukuti samples and used as test organisms for the study. Herbal extracts at the concentration of 40, 20, 10, and 2 mg/ml were tested against the test organisms to determine the antimicrobial property of the extracts. The herbal extract showing the greatest antimicrobial activity was selected for use in optimized product (sukuti) development. The total phenolic content of the herbal extracts was also determined. The analyses were performed in triplicate. The data were checked for homogeneity before being analyzed with ANOVA in Genstat Release v12. The Fisher's Least Significant Difference (LSD) method was used to compare data means at a 5% level of significance. Zanthoxylum armatum at 40 mg/ml concentration showed the largest zone of inhibition (ZOI) against the test organisms and was therefore selected for final product development. Meat strips (1 cm × 1 cm × 25 cm) were marinated with Zanthoxylum armatum (40 mg/ml) extract at the rate of 2%, aged (24 h at 4 ± 2oC), and dried in a cabinet dryer for 2 days at 55oC. The total plate counts (TPCs) of control (untreated)- and herbal (treated) sukuti were carried out for 20 days at an interval of 10 days to determine the microbial stability of the final product. The TPC for the treated sample was significantly lower (p<0.05) than that of the untreated sample.

Phytochemical constituents and antioxidant activity of fresh and cooked Tamarillo - an indigenous fruit - using different drying methods

Cyphomandra betacea is a shrub and flowering plant family of Solanaceae generating an egg shaped fruit. Tamarillo or tree tomato is the common name of the fruit. It is cultivated in Nilgiris districts of Tamilnadu and this fruit contains vitamins A,C,E and provitamin A and appreciable amounts of proteins, calcium, phosphorus, iron, zinc which helps to boost immunity. People consume the fruit as fresh, salad and juice forms. Chlorogenic acid content of the fruit helps to burn cholesterol and reduces the blood sugar level by functioning liver and pancreas. The fruit has sodium and potassium that helps to maintain blood pressure by regular intake. Anthocyanins and antioxidants of the fruit acts against free radicals and fights cancer. The aim of the study was to dry the fruits using different methods namely shade drying, cabinet drying, freeze drying and to identify the phytochemical constituents and analyse the antioxidant activity. The study shows that the fruit is attributed to an appreciable amount of bioactive components and good antioxidant activity. Tamarillo is a subtropical fruit, making fruits in dried form can preserve and secure out of season and available all over the year and the antioxidant activity of the fruit beneficial for human health.

Effect of blanching and drying processes on shelf‐life of Parkia speciosa seed and pods

AbstractParkia speciosa Hassk is an underutilized legume containing numerous nutrients with high perishability. The study was planned to extend the shelf‐life of P. speciosa seeds and pods with different treatments. Blanched and unblanched seeds and pods were subjected to freezing, freeze drying, cabinet drying, and sun drying. Samples were analyzed for nutritional, phytochemical, rehydration ratio, and overall acceptability score. Significant variation in nutritional value was observed in fresh and processed seeds as well as pods. Due to blanching, some minerals leached out resulting in lower ash content. Protein content was reduced slightly due to blanching and drying. Hot water blanching prior to drying, or freezing, inactivated the oxidative enzymes and preserved nutritional value. Freeze‐dried seed and pods had the highest % dehydration compared to other treatments. Blanched and unblanched, freeze‐dried samples had overall acceptance in an acceptable range for seed and pods. Freeze‐dried seeds and pods had longer storability without significant degradation of total antioxidants, phenols, ascorbic acid, overall acceptability, and rehydration ratio. Rehydration of freeze‐dried seeds and pods after blanching was highest. The study concluded that freeze drying along with blanching as pretreatment is effective in extending the shelf‐life of P. speciosa without a change in sensory profile.Novelty impact statementPerkia speciosa is one of the highly nutritious and underutilized legume, are explored for a shelf‐life extension for their seeds and pods, herein. Mere exposed to minimal pre‐processing treatments, they are made available in the longer term without any nutritional loss, appreciable rehydration extent, and overall acceptability profile as well. Thus, these minimal pre‐processing tactics adoption by agri‐entrepreneurs land the basis for value addition, malnutrition eradication, food security, and commercialization to contribute to the overall growth of the nation.

Drying methods effect on bioactive compounds, phenolic profile, and antioxidant capacity of mango powder

The effects of various drying methods (spray drying, cabinet drying, vacuum drying, tunnel drying, rotary oven drying, and gas oven drying) on the phenolic profile, bioactive compounds, and antioxidant capacity of mango powder have been considered with the aim of discover the effective drying technique. To identify and quantify the phenolic profile, the Folin-Ciocalteu method was used, while 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging studies were utilized to elucidate the antioxidant capacity. Results showed that total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and total carotenoid content (TCC) showed substantial variations (p < 0.05) between different drying methods, and the antioxidant properties were influenced to different degrees by drying methods. The antioxidant capacity of dried mango powder is strongly correlated with phenolic compounds (polyphenol, flavonoids, and anthocyanin). Caffeic acid was predominant among the 16 phenolics in mango powder. Flavonoids had higher retention factors (RF) than phenolic acids. Finally, our findings indicate that both cabinet drying and vacuum drying are appropriate for mango powder production. However, taking into account both economic viability and phenolic compound quality, cabinet drying would be the supreme choice for the outturn of mango powder as antioxidant-rich flavor enhancers.

Nutritional Evaluation of Orange-fleshed Sweet Potatoes (Ipomoea batatas) Flour Extracted from Various Processing Techniques

Orange flesh sweet potato (OFSP) is one of the world’s most important food security-promoted root crops. Unfortunately, the crop is underutilized in Nigeria due to its poor storability technics and rapid deterioration in storage. To establish baseline data for its better storage and utilization for upgrading its value chain, an alternative approach of processing is thereby expedient to curb the menace. Thus, the nutritional evaluation of orange-fleshed sweet potato (Ipomoea batatas) flour extracted from various processing techniques was evaluated. OFSP used for the study was sourced from National Root and Tubers Research Institute, Umudike, Nigeria. The experiment was carried out in the Department of Crop Production Laboratory, University of Agriculture and Environmental Science, Owerri, Nigeria. The three different processing techniques used were peeled; scratches peeled, and puree samples. The result of the proximate composition, mineral analysis of the flours and the puree showed significant differences among the samples evaluated. However, the crude protein content for both puree and scratched OFSP was insignificantly different. The puree sample recorded the highest protein content (5.48±0.24) and moisture content (85.95±3.89), respectively, and was closely followed by scratched OFSP with (5.02±0.01) while the least was recorded in the peeled sample (4.03±0.04). The study concluded that scratched OFSP through cabinet drier processing was considered the best alternative to the puree method of storage of orange-fleshed sweet potatoes and the best method of processing in areas where electricity is erratic or not available.

Drying Kinetic of Oven and Cabinet Dried Red Date Fruit

This study was carried out to evaluate the effect of pre-treatment technique (blanching) and temperature on the drying characteristics of the red date variety. Thin layer drying experiments were conducted at varying drying temperatures of 50, 60 and 70 °C using electrical laboratory oven and cabinet dryer with a constant air velocity of 1.4 m/s. Other sets of samples were blanched at 50 °C for 2-, 5- and 10-minutes before being dried at varying drying temperatures of 50, 60 and 70 °C respectively under the same drying conditions. The drying process took place mainly in the falling rate period indicating that the mechanism that governed moisture movement in the samples was diffusion. The drying curve showed that blanched red date fruits had higher drying rate than the un-blanched samples. The result is useful for farmers, researchers, and the processing industry in designing a reliable machine for processing red date fruit which will boost the small and medium scale production of the fruit in Nigeria.

Dehydrated Food Waste for Composting: An Overview

Food waste disposal has recently received much attention worldwide due to its major impact on environmental pollution and economic costs. Using high moisture content of food waste has the highest negative environmental impact due to increased greenhouse gas emissions, odor, and leachate. Drying technologies play an important role in reducing the moisture content of food waste, which is necessary for environmental sustainability and safety. The first part of this review highlights that sun-drying is the most cost-effective drying method. However, it has not been widely recommended for food waste management due to several limitations, including the inability to control sunray temperature and the inability to control end-product quality. Thermal drying eliminates moisture from food waste quickly, preventing hydrolysis and biodegradation. Thermal dryers, such as the GAIA GC-300 dryer, and cabinet dryer fitted with a standard tray, are the best alternative to sun drying. The second part of this review highlights that dehydrated food waste products are slightly acidic (4.7–5.1), have a high electrical conductivity (EC) value (4.83–7.64 mS cm-1), with high nutrient content, due to low pH levels, dehydrated food waste is not suitable for direct use as a fertilizer for the plants. So, the dried food waste should be composted before application to the plants because the composting process will dominate the limitation of phytotoxins, anoxia, salinity, and water repellence. Trench compost can be a good choice for decomposing dried organic waste because trench compost relies solely on soil decomposing microorganisms and insects.

Effect of Pre-Treatment on Drying of Red Amaranth and its Utilization in Noodles Preparation

Red amaranth is a perishable, colored leafy vegetable that can be preserved through a variety of methods, including dehydration. The current study was conducted to investigate the effect of pre-treatments (blanching, sulphitation, and blanching plus sulphitation) and drying methods (cabinet and solar) on drying rate and color intensity of red amaranth (leaves and stems) and the development of red amaranth enriched noodles. Drying rate and color intensity were varied in different degrees based on applied pre-treatment and drying method. For drying of red amaranth leaves, blanching plus sulphitation followed by cabinet drying showed highest drying rate (0.67 h-1), whereas blanching followed by cabinet drying showed fastest drying rate (0.69 h-1) for red amaranth stems. Color absorbance study revealed that sulphitation pre-treatment and cabinet drying leads highest color absorbance (0.261) in red amaranth leaves, while blanching and cabinet drying provides highest color intensity (0.121) in stems. The use of red amaranth leaves powder in noodles preparation at 5% and 10% wheat flour substitutions gave significantly different (p&lt;0.05) sensory parameters. Substitution of 5% wheat flour by sulphited and cabinet dried red amaranth leaves powder gave the highest overall acceptability of developed noodles.

Mathematical Modelling of Potassium Meta-Bisulphite Treated Mango (Mangifera indica) Slices cv Dasheri

Fresh and ripe mango (Mangifera indica) slices cv Dasheri were dehydrated in a cabinet dryer at drying air temperatures of 50, 60, and 70 oC at a slice thickness of 5 mm. Before dehydration, the mango slices were pre-treated with potassium meta-bisulphite (KMS) at three levels (0.5 %, 1.0 %, and 1.5 % KMS, respectively). Five semi-theoretical and empirical thin-layer drying models (Newton [Lewis], Logarithmic, Demir et al. 2004, Henderson &amp; Pabis, and Wang &amp; Singh) were employed to select the best model that describes the drying process. Moisture diffusivity and activation energy of the mango slices were also evaluated. It was observed that the drying took place in the falling rate period. Demir et al. 2004 and Logarithmic models were found to satisfactorily describe the drying process of the mango slices using R2, x2, SSE, and RMSE as the criteria for selecting the best model. The mango slices' moisture diffusivity and activation energy range from 6.79 to 10.02×10-8 m2/s and 10.03 to 14.73 kJ/mol. Thus, KMS pre-treatment can minimise the mango slices' drying duration and drying cost.

Drying kinetics and quality aspects of bitter gourd (Momordica charantia) dried in a novel cabinet dryer

An attempt was taken to investigate the effect of drying air temperature and slice thickness on the drying kinetics and quality of bitter gourd (Momordica charantia) dried in a novel cabinet dryer (HSTU Fruit and Vegetable Dryer). Fresh bitter gourd was sorted, cleaned, and sliced at 4 mm, 6 mm, and 8 mm thickness. All the samples were blanched in boiling water at 100°C for 3 mins. Then the slices with an initial moisture content of 96.47±0.6% were dried, spreading as a thin layer in the trays of the cabinet dryer using three drying air temperatures of 60, 70, and 80°C until the desired final moisture content (MC) of 4.66±0.4% was obtained. The results indicated that the shortest drying time (2.08 hrs) was required by the sample of 4 mm thickness, which was dried at 80°C to reduce moisture from 96.47±0.6% initial (wet basis, wb) to 4.66±0.4% final moisture (wb). The sample of 8 mm thickness dried at 60°C took the longest drying time (6.67 hrs). The higher drying rate (34.32 gm H2O/min.cm2 ) was noticed at a constant drying rate period in the case of a 6 mm thick slice at 70°C. Whereas a lower drying rate (9.29 gm H2O/min.cm2 ) was observed for drying 8 mm slices using 60°C air temperature. Even though, the effect of blanching on drying characteristics of bitter gourd was not noticed so much, the drying rate was found to be increased slightly of pretreated bitter gourd thus drying time was shorter. A comparison on colour analysis of both fresh and blanched bitter gourd showed that a 6 mm slice dried at 70°C was found better in retaining green colour than other samples. The rehydration ratio (6.63±0.62) and the percentage of water uptake (86.75±0.58) of rehydrated pretreated bitter gourd were also higher in a dried sample of 6 mm. Therefore, pretreated bitter gourd is suggested to dry quickly using 70oC in a cabinet dryer slicing at 6 mm thickness to obtain a better quality dried product.

Adsorption Isotherms and Thermodynamic Properties of Dried Tomato Slices

Moisture adsorption isotherms and thermodynamic properties of dried tomato slices obtained from four tomato varieties were investigated. Freshly harvested tomatoes were pretreated with potassium metabisulphite solution (0.2%, weight/volume) before drying in a cabinet dryer at 60± 2° C. Moisture adsorption behavior of the dried tomato slices was determined using the static gravimetric method at 25, 30 and 40o C. The data fitted to GAB, M.BET, DLP, Smith and Oswin sorption models. The isosteric heat of sorption was also determined. Moisture adsorption isotherm of dried tomato slices from UC82B, Roma, Eva-F1 and Kerewa varieties exhibited a sigmoid isotherm curve typical of type II BET classification. Increase in temperature resulted into a decrease in the equilibrium moisture content. The GAB, DLP and modified BET model adequately modeled the isotherms of dried tomato slices. The relationship between isosteric heat of sorption and the equilibrium moisture of dried tomato slices were accurately described by exponential model.

Effect of Some Processing and Storage Methods on the Quality of Okra (Abelmoschus esculentus)

Three experiments, comprisin packaging of fresh Okra for storage, dipping of fresh fruits in hot water before packaging to store and drying of sliced Okra fruits, were carried out in the laboratory at the Department of Horticulture, Kwame Nkrumah University of Science and Technology. The objective of the study was to assess the effect of some processing and storage methods on the quality of okra. The experimental design used for the storage work was Completely Randomized Design (CRD). There were 10 treatments for the experiment. A portion of plot measuring 14m x 40.5m was demarcated for planting and drying was done by using a solar cabinet dryer located at the old site of Forestry Research Institute of Ghana, located on the compound of the Kwame Nkrumah University of Science and Technology. Results from the first experiment which involved packing and storing of fresh okra fruits indicated that, Fresh okra fruit packed in both polypropylene and polyethylene bags and store at 7- 9 C can stay up to 24 days with no significant (p ≤ 0.05) weight lost. However produce packed in perforated polypropylene and polyethylene bags gave a higher salvage of 82.1% compared to 77% from those packed in the imperforated bags of the two packaging materials. The second experiment which involved hot water treatment of okra fruit before packaging for storage indicated a very fast rate of deterioration of fruits, with no fruit being salvaged at the end of the storage period. The third experiment involving slicing and drying of okra fruits in a solar cabinet dryer indicated that samples from both stages of maturity dried for 24hours lost comparatively less weight than those dried for 48hours. This shows that the longer the drying period, the more the lost in weight. From the three experiments it was concluded that packaging and storage of fresh okra fruit enables the fruit to keep longer and remained in the useable state than unpacked storage. Harvesting fruit at 4 and 6days, after setting for storage is appropriate, however those harvested at 6days after setting will come out with greater number of unusable fruit after the storage period. On the choice of packaging material one should prefer polypropylene to polyethylene for bitter results. Also perforation of the chosen material had advantages over the imperforated ones. Hot water treatment of okra fruits can be applied under situations where the fruits may be used within 16 days or less but not longer.

FARMERS' PROSPERITY THROUGH SOLAR DRYING OF DATES

Drying is an essential process in the preservation of agricultural products. Various drying methods are employed to dry different agricultural products. Each method has its own advantages and limitations. Choosing the right drying system is thus important in the process of drying agricultural products. Care must be taken in choosing the drying system. Study comparing traditional drying and other drying methods for the reduction of the drying time and to a significant improvement of the product quality in term so color texture and taste. Drying reduces the possibilities of the contamination by insects and microorganisms so that product is prevented. An experimental study was performed to determine the drying characteristics of dates halves using hot air dryer, solar dryer and open sun drying methods. The date fruits (Phoenix dactylifera) are as a food of high energy value. It is very popular both nationally and internationally. Date fruits are perishable fruit crop grown in coastal region of kutchh of Gujarat state. The date fruits are harvested at ripening stage so the fresh fruits have not longer shelf life. The date halves were dried under hot air flow dryer at temperature level of 50, 60 and 70oC under pre-treatment of blanching and un-blanching. The rate of moisture of blanched sample should only 7.5 % reduction at 54hr drying period while un blanched sample should 13.9 % reduction at 102 hr. In case of date halves drying, the constant weight of sample was achieved at 56 h of drying period in solar cabinet dryer as compared to 320 h for open sun drying. The moisture content was reduced from 69.5 to 8.7 % (w.b.) under solar cabinet dryer for drying of 56 h, while the moisture content was reduce 69.5 to 12.3 % (w.b.) under open sun drying for drying period of 320 h. It was found that the highest moisture removal was 67% for the drying time of 54 h. under hot air flow dryer at 70 oC while minimum moisture removal was 63.6 % for drying time of 320 h. under open sun drying method. In hot air flow drying method, the drying rate for date halves was found to be 32.54, 46.37 and 62.03 g/h at temperature level of 50, 60 and 70 oC respectively for blanched samples, while it was 31.56, 45.53 and 60.93g/h at same temperature levels for unblanched samples.