Average Moisture Content Research Articles

Optimizing Soil Moisture Conservation and Temperature Regulation in Rainfed Jujube Orchards of China’s Loess Hilly Areas Using Straw and Branch Mulching

The implementation of the “Returning Farmland to Forest” project in the loess hilly region of China has led to the establishment of large-scale economic forests, which have become the dominant industry driving local economic development. However, the region faces challenges such as drought, water shortages, and an uneven distribution of precipitation, which have a severe impact on the growth of economic forests, including jujube trees. Water stress significantly reduces yield and efficiency, posing a threat to the sustainable and healthy development of jujube ecological and economic forests. Therefore, this study aimed to address these issues by implementing straw mulching (SM) and jujube branch mulching (BM) measures in the mountainous jujube economic forests. Through long-term monitoring and statistical analysis, the study investigated the effects of different mulching treatments on soil moisture and soil temperature. The research findings reveal that both SM and BM significantly increased soil moisture in the 0–280 cm soil layer during the jujube growing season (p < 0.05). In both normal precipitation (2014) and drought (2015) years, SM increased average soil moisture content by 5.10% and 4.60%, respectively, compared to the uncovered treatment (CK). SM also had a positive impact on the soil moisture content in each layer of the soil profile. However, BM only increased soil moisture content in the 40–100 cm and 220–280 cm soil layers. Additionally, SM and BM reduced the variation of soil moisture, with SM showing a more significant effect in regulating soil moisture and achieving more stable moisture levels. During the jujube growing seasons in 2014 and 2015, SM and BM decreased soil temperature in the 0–10 cm soil layer. The temperature difference compared to CK decreased with increasing soil depth. SM had an overcooling effect, while BM reduced the temperature before the fruit expansion period and maintained warmth afterward. Both SM and BM also reduced the daily range and variation range of soil temperature, with SM having a more pronounced effect. The temperature of the 0–20 cm soil layer exhibited the strongest correlation with air temperature, and SM showed the weakest response. In conclusion, adopting straw mulching and jujube branch mulching in rain-fed jujube orchards in the loess hilly region not only saves materials and reduces costs but also contributes to water retention and temperature regulation. Straw mulching, in particular, plays a more significant role in moisture retention and temperature regulation and is advantageous for soil management in rain-fed jujube orchards. These research findings provide a scientific basis for optimizing water and heat management in orchards with limited water resources.

Energy and quality analysis of forced convection air-energy assisted solar timber drying

Discontinuities due to weather conditions and daylight affect solar drying, so to address that, a working mechanism of air energy-assisted solar drying was developed in this study. An air-energy assisted solar dryer was used to dry timber, from a green average moisture content of 183%–11.3% in 161.5 h, where the moisture diffusion coefficient ranged from 1.28 ×10-10 m2/s to 6.41 ×10-9 m2/s. The effective solar radiation intensity during drying ranged from 221.3 to 750.3 W/m2. The overall drying efficiency was 30.7%, and the effective solar heat supply ratio was 58.5%. The specific moisture extraction rate and specific energy consumption were measured within a range of 0.32–3.0 kg/kWh and 924 - 11390 kJ/kg, respectively. The average power consumption per m3 of wood volume was 254.2 kW h/m3. The results showed that the energy-assisted solar dryer was suitable for a condition with low radiation and various weather conditions.

Sifat Fisika dan Mekanika Kayu Acacia aulacocarpa dari KHDTK Wanagama

This study aims to determinethe physical properties and mechanical properties at axial (base, middle, and top) and radial (near the pith, middle, and near the bark) positions, as well as the relationship between the specific gravity and mechanical properties of Acacia aulacocarpa wood. Three 27-year-old trees planted at KHDTK Wanagama wereused. Wood physical and mechanical propertieswere tested per British Standard 373:1957. The statistical analysis used was a two-way ANOVA and a follow-up test of Tukey HSD. The results showed that the average moisture content was 98.95%; the green and air-dry sepesific gravity were 0.58 and 0.61. Radial, tangential, and longitudinal shrinkage from green to oven-dry conditions (total shrinkage) were 2.02%, 5.09%, and 0.33%. The tangential/radial (T/R) ratio was 2.80%. The static bending strength of stress at proportion limit, MoE, and MoR were 498.13 kg/cm2, 116.16x1000 kg/cm2, and 1043.68 kg/cm2, respectively. The compressive strength parallel to the grain and perpendicular to the grain were 596.05 kg/cm2 and 227.25 kg/cm2, respectively. The results of the variance analysis showed that the radial position factor has a significant effect on green moisture content, green and air-dry specificgravity, total radial shrinkage, T/R ratio, static bending strength at stress of proportion limit, MoE, MoR, compressive strength parallel to the grain, and compressive strength perpendicular to the grain. However, the axial position factor did not show any significant differences in the physical and mechanical properties of the wood. Furthermore, air-dry specific gravity has a significant moderate to high positive correlation with all mechanical properties.
 Keywords: Acacia aulacocarpa, physical properties, mechanical properties, axial position, radial position

Production of biodegradable composite plates from cross-linked starch and cellulosic fibers

Plastic used in food packaging causes permanent damage to living things. Therefore, biodegradable packaging has gained importance. In this study, biodegradable composite plates made from cross-linked wheat starch and cellulose-based fibers were examined for their physical and mechanical properties. The mechanical and physical properties were significantly altered when the obtained composite plates were examined. According to texture analysis, the plate with the lowest brittleness and with the highest crushing toughness value was produced from 7% carboxymethylcellulose. The densities of the composite plates obtained from cross-linked wheat starch were found to be 0.171 g/cm³, and their densities were found to be lower than the composite plates produced from natural wheat starch. It was determined that the plate with the highest water resistance was produced from 7% carboxymethyl cellulose. Added cellulosic fibers (commercial cellulose, linter fiber, hemp fiber) reduced moisture absorption from the air, reducing the average moisture content to 8.71. All of the plates produced with 7% linter fiber, which has the lowest moisture content, completely disappeared from nature within 40 days.

Experimental Study of Glued Laminated Timber (Glulam) from Jackfruit Wood and Coconut Wood for Timber Beams of Level Houses in East Nusa Tenggara

Wood is a construction material that is familiar to the wider community. Wood can be used in construction. The purpose of this study was to determine the specifications of the physical properties, mechanical properties, tensile strength and flexural strength of laminated wood (glulam), in jackfruit and coconut wood beams originating from the East Nusa Tenggara region in multi-storey house buildings. The tests carried out included testing the water content, testing the tensile strength and bending strength, testing the tensile strength and bending strength on glulam beams using epoxy glue adhesives. The results of this study showed that jackfruit wood and coconut wood aged 15 years and 20 years had an average moisture content of 15 years, namely 15% and 26%, the average specific gravity was 0.54 (tons/m3) and 0.46 (tons/m3). Meanwhile, the average water content for 20 years is 15% and 32%, the average specific gravity is 0.58 (Ton/m3) and 0.45 (Ton/m3). The tensile strength of intact and glulam wood of jackfruit and coconut wood was obtained from laboratory results on SNI 7973-2013 calculations, the average tensile strength of intact jackfruit and coconut wood was 84.40 MPa and 80.73 MPa. The flexural strength of intact beams and glulam of jackfruit and coconut wood aged 15 years was obtained from laboratory results on SNI 7973-2013 calculations of the flexural strength of intact beams for 15 years, the average being 71.81 MPa and 26.07 MPa. At 15 years of age, the flexural strength of glulam beams was the highest variation 1 and variation 2 (Jackfruit, Coconut, Jackfruit) mean 76.00 MPa and 41.85 MPa. The flexural strength of intact beams and gulam of jackfruit and coconut wood aged 20 years was obtained by laboratory results on SNI 7973-2013 calculations of flexural strength of intact beams, which were 80.27 MPa and 29.73 MPa respectively. At the age of 20 years, the highest flexural strength of glulam beams were variations 1 and 2 (Coconut, Jackfruit, Coconut) with an average of 80.40 MPa and 48.76 Mpa.

Calibration of volumetric soil moisture using Landsat-8 and Sentinel-2 satellite imagery by Google Earth Engine

Water scarcity for agriculture is increasingly evident due to climatic alterations and inadequate management of this resource. Therefore, developing digital models that help improve water resource management to provide solutions to agronomic problems in northern Mexico is necessary. In this context, the objective of the present research is to calibrate the Optical Trapezoid (OPTRAM) and Thermal-Optical Trapezoid (TOTRAM) models to estimate the volumetric soil moisture at different depths through vegetation indices derived from Landsat-8 and Sentinel-2 satellite images using Google Earth Engine (GEE). Agricultural areas under gravity irrigation and rainfed runoff in the Comarca Lagunera, the lower part of the Hydrological Region No. 36 of the Nazas and Aguanaval rivers were selected for in-situ measurements. The OPTRAM and TOTRAM normalized moisture content (W) estimates were compared with in-situ volumetric soil moisture (Ɵ) data. Results indicate that the predictions of OPTRAM errors using Sentinel-2 images showed RMSE between 0.033 to 0.043 cm3 cm-3 and R2 between 0.66 to 0.75, whereas Landsat-8 errors showed RSME from 0.036 to from 0.036 to 0.057 cm3 cm-3 and R2 between 0.70 to 0.81. On the other hand, TOTRAM errors showed RMSE between 0.045 to 0.053 cm3 cm-3 and R2 between 0.62 to 0.85 through calibrations. This study made it possible to evaluate the most accurate combinations of the pixel distributions of each model and vegetation indices for the estimation of volumetric soil moisture within the different phenological stages of the crops.

Engineering Properties of Onion Seeds for Sustainable Agricultural Machinery Design

The engineering properties of the crop are an important factor in effectively designing agricultural machines. In terms of onion seeding or planting, various physical, mechanical, and frictional properties play a crucial role in the development of planting machines and performance assessment. The study on the engineering properties of onion seeds and their implications for agricultural machinery design supports the adoption of sustainable agricultural practices. Efficient and precise planting systems can optimize resource utilization, reduce wastage, and enhance overall agricultural productivity. This focus on engineering aspects in machinery design indirectly contributes to sustainable agriculture practices, which prioritize minimizing environmental impacts while ensuring food security. Ultimately, by emphasizing the importance of engineering properties, the study promotes the development of agricultural systems that align with sustainability goals. In this study, various engineering properties of onion seeds concerning the different soaking times have been studied. An experiment was performed to assess the change in engineering properties of onion seeds (Gavran, Puna fursungi, and KSP-117) by soaking them in water with a predefined duration (Dry seed, Day 1 and Day 2). The average moisture content of onion seeds varied from 9.44 to 40.87 % (d.b.). Sphericity, aspect ratio, geometric mean diameter, and thousand seed weight varied in the range from 0.72 to 0.77, 0.71 to 0.76, 2.05 to 2.18 mm, and 3.50 to 6.75 g, respectively. The bulk density of onion seeds was observed in the range of 489.64 to 526.24 kg/m3. It was observed that there was a gradual increment in bulk density with an increase in soaking time. However, a gradually decreasing trend was observed in the case of true density. The true density of onion seeds varied from 1127.14 to 1245.64 kg/m3. The coefficient of friction of onion seeds on a selected material (Wood, Plastic, Mild steel, and Aluminum) showed gradual growth concerning the soaking time.

Enhancement of thermal and techno-economic performance and prediction of drying kinetics of paddy dried in solar bubble dryer

The development and performance evaluation of a solar Bubble drier (SBD) for drying agricultural produce are presented in this study. In order to evaluate the solar bubble dryer's performance in terms of drying characteristics and end-product economics, it was compared to the solar tunnel dryer (STD). A solar tunnel dryer is a structure with a tunnel-like shape that is covered in UV-stabilized polythene sheet so that industrial and agricultural items can be dried off. While there was no load, the maximum temperatures inside the solar bubble dryer and solar tunnel dryer were 56.25 and 49.30 °C, respectively. When there was a full load, the maximum temperatures inside the dryer were 49.55 and 33.20 °C, respectively. For solar bubble dryers, the average final moisture content ranged from 13.07±0.335 % to 18.74±0.716 % (w.b.), while for solar tunnel dryers, it ranged from 13.60±0.575 % to 20.60±0.751 % (w.b.). The mean drying rate also varied depending on the drying air temperature and air flow mode, ranging from 0.081±0.020 to 0.006±0.005 kg/kg dm-h for solar bubble dryers and 0.056±0.025 to 0.005±0.002 kg/kg dm-h for solar tunnel dryers. The thermal efficiency of the developed dryer was found to be 58.39% for solar bubble dryers and 48.09% for solar tunnel dryers, which are significantly higher than that of other general Sun drying (36%). However, the drying rate varied between 0.081 to 0.006 g of water evaporated per g of dry matter per hour when solar bubble dryer was adopted and 0.014 to 0.007 g for solar tunnel dryer. Economic analysis showed that the SBD and STD had payback periods of 3.23 and 2.54 years, respectively. However, the cost of drying came lower for the SBD than the STD, which were Rs. 1.51 per kg and Rs. 1.76 per kg.

ANN and RSM based Modeling of Moringa Stenopetala Seed Oil Extraction: Process Optimization and Oil Characterization

Moringa Stenopetala is a plant species that is endemic to the southern region of Ethiopia. It is primarily cultivated for its nutritional value and is considered an important food source. The present research aimed to analyse the physicochemical properties of Moringa Stenopetala seed oil (MSO) obtained through solvent extraction method utilising hexane as the solvent. The collection of seeds was conducted in Adama, which is situated in the East Shawa zone of Oromia, Ethiopia. Prior to the extraction procedure, the seeds' average moisture content, crude ash, fibre, protein, and oil content were analysed and found to be 6.27%, 7.8%, 2.7%, 26.5%, and 43.2%, respectively. Using the Response Surface Method (RSM) and Artificial Neural Network (ANN), the extraction process was modeled. The study utilised numerical solutions to determine the optimal process parameters for maximising oil yield during extraction. The results indicated that a particle size of 0.85mm, a temperature of 85°C, and an extraction time of 4.75 hours were the most effective parameters. Furthermore, an investigation was conducted on the physical and chemical properties of the oil obtained under optimised conditions.

An Assessment of the Cultivation Potential and Suitability for Human Consumption of Mediterranean Mussels (Mytilus galloprovincialis Lamarck, 1819) from the Yalova Coast of the Marmara Sea

This study aimed to determine into potential suitability of juvenile Mediterranean mussel (Mytilus galloprovincialis) for cultivation and human consumption collected from various stations (Kapaklı, Çınarcık, Koru, and Deveboynu) along the Yalova coast of the South Marmara Sea during the spring season. Specifically, meat yield, condition index, moisture content, density of fouling organisms on the shells, and heavy metal concentrations (copper, zinc, mercury, cadmium, lead, and arsenic) were analysed. The average meat yields for Çınarcık, Deveboynu, Kapaklı, and Koru were found to be 24.51±2.96, 21.72±3.92, 23.75±2.31, and 21.54±4.01, respectively. Similarly, the average condition index were found to be 7.29±1.16, 6.02±0.97, 7.30±0.77, and 5.94±1.39 for Çınarcık, Deveboynu, Kapaklı, and Koru, respectively. The average shell component index for Çınarcık, Deveboynu, Kapaklı, and Koru were detected that 72.06±2.75, 74.39±4.13, 69.99±2.55, and 74.68±4.54, respectively. Additionally, the average moisture contents were found to be 82.63±1.95, 83.34±3.23, 84.02±1.82, and 83.40±4.17 for Çınarcık, Deveboynu, Kapaklı, and Koru, respectively. The statistical analysis revealed significant differences (p<0.05) in these parameters among the stations. Moreover, the quantities of competitive and fouling organisms, such as polychaetes and barnacles, were found to be highest in the Deveboynu and Koru stations. It has been determined that copper, zinc, mercury, and lead levels of the mussels are suitable for human consumption in all stations. However, arsenic values exceeded legal limits in Çınarcık, Koru, and Deveboynu, and cadmium values exceeded legal limits in all stations.

Nutritional Composition of Seeds of False Mopane (Guibourtia coleosperma) from Shakawe and Kasane Areas, Northern Botswana

The seeds of Guibourtia coleosperma serve as potential source of nutritious food for rural communities in northern Botswana though underutilized. The objective of this study was to determine the proximate and mineral composition of G. coleosperma seeds collected from northern Botswana. Seed samples were collected from Shakawe and Kasane areas in northern Botswana. The proximate composition and mineral contents of the seed were determined following standard procedures. The data were analyzed using T-test. Seeds collected from Shakawe had average moisture (%), crude fat (%), crude fiber (%), crude protein (%), ash (%), total carbohydrate (%) and energy (kcal/100g) contents of 8.48 ± 0.29, 9.24 ± 0.31, 4.72 ± 0.60, 15.34 ± 0.48, 2.40 ± 0.02, 59.81 ± 1.00 and 383.80 ± 4.81, respectively. The corresponding values for seeds collected from Kasane were 9.00 ± 0.10, 10.17 ± 0.37, 7.13 ± 0.21, 16.44 ± 0.43, 2.45 ± 0.02, 54.80 ± 0.58 and 376.50 ± 2.22, respectively. Seeds collected from Kasane had significantly higher (p< 0.05) crude fat, crude fiber, crude protein and ash contents than seeds collected from Shakawe. However, the total carbohydrates content of seeds collected from Shakawe was significantly higher (p< 0.05) than those collected from Kasane. No significant differences (p> 0.05) were observed for moisture and energy contents between the seed samples collected from the two locations. The predominate proximate component in the seeds was total carbohydrate followed by crude protein and, therefore, the seeds can serve as good sources of energy and protein. The average zinc, iron, magnesium, potassium, calcium, sodium (mg/100 g) and phosphorus (mg/g) contents of seeds collected from Shakawe were 2.96 ± 0.53, 2.40 ± 0.27, 116.80 ± 2.82, 468.69 ± 19.28, 316.70 ± 21.15, 1.21 ± 0.67 and 1.35 ± 0.04, respectively. The corresponding values for False Mopane seeds collected from Kasane were 2.53 ± 0.31, 3.34 ± 0.18, 173.65 ± 5.83, 460.86 ± 10.53, 367.59 ± 15.37, 3.51 ± 0.44 and 1.45 ± 0.12, respectively. The values for iron, magnesium, calcium and sodium were significantly higher (p< 0.05) for seeds collected from Kasane than those collected from Shakawe. However, no significant differences (p> 0.05) were observed between the seed samples collected from the two locations for zinc, potassium and phosphorus. Quantitatively, the predominant mineral observed in seed was potassium followed by calcium. The seeds could serve as good source of magnesium, iron, zinc, calcium and potassium since they contribute higher proportions of the recommended daily intake of these minerals. The results showed that location has a significant effect both on the proximate composition and mineral contents of False Mopane seeds.

PENGEMBANGAN COOKIES BERBASIS TEPUNG BIJI KLUWIH (Artocarpus Communis)

Cookies are a snack favored by Indonesians because they have an attractive taste and shape. Currently the use of flour from tubers and other local foods such as kluwih seed flour in making cookies can increase the nutritional value of cookies as well as reduce dependence on flour. This study aims to determine the effect of adding kluwih seed flour on the organoleptic and chemical properties of cookies, using an experimental method with a completely randomized design (CRD) with 1 treatment factor, namely the difference in the addition of kluwih seed flour (10%, 15% and 20%). The research was conducted at the Organoleptic Laboratory of the Department of Nutrition, Health Polytechnic of the Aceh Ministry of Health and the Laboratory of Animal Nutrition and Animal Feed Technology, Faculty of Agriculture, Syiah Kuala University. Statistical analysis using the ANOVA test. On average, the panelists gave favorable responses (4.16 - 4.38) to the color, taste, aroma and texture of cookies with the addition of 10% kluwih seed flour (F1), while for cookies with the addition of 15% kluwih seed flour (F2) and 20% (F3) of the panelists gave somewhat favorable response (3,77−3,86). The results of the chemical properties test showed that the three treatments for cookies had an average moisture content of 2.69-3.02%, ash 1.17-2.57%, fiber 1.70-3.55%, protein 5.16-6. , 03% fat 23.82-23.98% and carbohydrates 65.74-66.30%. Conclusion, the addition of kluwih seed flour had a significant effect on the organoleptic properties of cookies (Pvalue 0.05), and had no significant effect on the chemical properties of cookies (Pvalue 0.05). Keywords: Cookies, kluwih seed flour, chemical test, organoleptic test

Permeability of wood impregnated with polyethylene wax emulsion in vacuum

Polyethylene wax (PEW) has emerged as a commonly used material for maintaining the quality of wood. The emulsification of solid PEW before being injected into wood can effectively overcome the shortcomings of the high-temperature melting and injection process of solid PEW. The permeability of Eucalyptus (Eucalyptus saligna) and Mongolian Scotch pine (Pinus sylvestris var. Mongolica) to PEW emulsion in vacuum environment was investigated using impregnation tests, and steaming pretreatment and microwave irradiation pretreatment were applied. The small particle size and low viscosity of the PEW emulsion, whose median particle size was 0.256 μm and viscosity was 52.2 mPa s (at 60 r/s), facilitated its penetration into the wood capillary system. The weight percent gain (WPG) of Eucalyptus and Mongolian Scotch pine post impregnation in vacuum was positively correlated with both the vacuum-holding time and the impregnation temperature, but after 60 min of impregnation the WPG of both wood species decreased significantly. Both pretreatment methods could substantially improve the wood permeability and effectively promote the penetration of the PEW emulsion into the wood. The maximum WPG was achieved when Eucalyptus and Mongolian Scotch pine were respectively steamed for 80 min and 120 min. There was an increase of 0.24 times for the former and an increase of 0.53 times for the latter compared to unpretreated wood. Both species exhibited the highest WPG after water immersion for 60 min (with average moisture content close to their fibre saturation point) and microwave irradiation for 30 s, which was respectively 0.28 and 0.75 times higher than that of unpretreated wood. There was a significant variation in WPG between the two species with the same pretreatment method. The relatively lower density and better-developed capillary system of Mongolian Scotch pine allowed more efficient penetration of PEW emulsion. It is recommended that, considering the time cost and practical enhancement, microwave irradiation should be given priority to when pretreating wood.

Process development for paneer preparation from sheep milk of Hassan breed

Sheep milk has high nutritional value and high concentrations of proteins, fats, minerals, and vitamins as compared to the milk of other domestic species. The high levels of protein, fat and calcium make it an excellent matrix for cheese production (Park et al., 2007). In order to explore the possibilities of preparation of value added product from the local sheep breeds (Hassan breed, Karnataka), a study been taken place to prepare the paneer using curd and citric acid as coagulants. Nutritional composition of Paneer samples prepared from sheep milk of Hassan breed is presented in Table 1. The average yield, moisture, Fat, Protein, Lactose, Acidity and total Ash contents of paneer prepared from sheep milk of Hassan breed using curd as coagulant are 91, 53.90, 23.28, 15.6, 2.67, 0.22 and 2.85, respectively. The average yield, moisture, Fat, Protein, Lactose, Acidity and total Ash contents of paneer prepared from sheep milk of Hassan breed using citric acid as coagulant are 70, 52.12, 23.06, 15.12, 2.53, 0.28 and 2.91, respectively.

Insight into oil-water interfacial behaviors of whey protein isolate and sterol towards stabilizing high internal phase Pickering emulsion gels

This investigation elucidated stabilization of high internal phase Pickering emulsion gels (HIPPEGs) on the basis of oil-water interfacial adsorption properties of particles. The particles were prepared by whey protein isolate (WPI) and two structurally different sterols, including ergosterol (ES) and γ-oryzanol (γS). Initially, oil-water interfacial adsorption properties were improved in the presence of sterol. And WPI-γS exhibited higher contact angle and lower dynamic interfacial tension than WPI-ES. Quartz crystal microbalance with dissipation monitoring measurement further proved that adsorption mass and viscoelasticity of WPI-γS was higher than those of WPI-ES. Furthermore, WPI-sterol HIPPEGs showed lower average particle size and moisture content, higher absolute value of ζ-potential than WPI-stabilized HIPPEGs. Apparent viscosity, storage modulus and loss modulus of WPI were improved after the addition of sterol. Moreover, WPI-γS HIPPEGs exhibited higher stabilities and viscoelasticity than WPI-ES HIPPEGs. Additionally, compared with WPI-stabilized HIPPEGs, WPI-γS-loaded HIPPEGs showed shorter relaxation time and more uniform color distribution, indicating that droplet flow was restricted and more uniform, followed by WPI-ES-loaded HIPPEGs. Finally, super-resolution microscope results exhibited that sterol inhibited emulsion droplets aggregation due to steric hindrance. HIPPEGs stabilized by WPI-γS showed more homogeneous and smaller droplets than WPI-ES-loaded HIPPEGs. This work provided a theoretical support for stable HIPPEGs formed with protein-sterol particles, which would be applied to replace trans fats and cholesterol in various food products.

Mathematical Modelling of Heat and Mass Transfer during Jackfruit Drying Considering Shrinkage

Shrinkage is an obvious phenomenon that occurs when drying plant-based food materials, and it has a crucial influence on heat–mass transfer mechanisms, energy consumption in drying, and dried product quality. The present study aims to develop a theoretical shrinkage model considering the drying kinetics and shrinkage velocity approach during the convective drying of jackfruit. Since there is no theoretical model in the literature that considers the transfer process along with shrinkage phenomena for jackfruit drying, this work focuses on presenting the drying and shrinkage kinetics behaviour through the development of a mathematical model. Two distinct models were developed, each considering the presence or absence of shrinkage phenomena. Model validation was carried out by comparing the predicted results with experimental data from drying tests conducted at 60 °C, and model accuracy was evaluated through statistical error analysis. In the shrinkage-induced model, the shrinkage exhibited a linear relationship with drying time, as the moisture content decreased from 5.25 to 0.47 kg/kg on a dry basis when the temperature increased to 54 °C. Notably, the shrinkage-induced model demonstrated superior performance, displaying low mean absolute error (MAE) values—0.27 kg/kg on a dry basis for moisture content, 2.07 °C for temperature variation, and 0.04 for shrinkage, when compared to the model without shrinkage. Furthermore, the mean relative error (MRE) values for the shrinkage-induced model were 45.71% and 33.33% lower than those of the model without shrinkage for average moisture content and temperature, respectively. The findings of this study provide valuable insights for the food drying industry, offering new knowledge about drying kinetics and shrinkage characteristics that can contribute to the development of energy-efficient drying systems.

Intermittent Drying of Soybeans in Conical Spouted Beds: Modeling Approach

Intermittent drying is a promising methodology to conventional drying which offers benefits related to energy and better-quality products. However, modeling of this technique remains a challenge. Thus, this study aims to propose a fully predictive model for intermittent drying in conical spouted bed dryers. A single-phase model is used to account for the heat and mass transfer on the soybean surface and their inside, and the predictions are compared with the experimental results. The proposed model provides physically consistent results and is coherent with the experimental data, mainly for drying under moderate air temperatures with moderate and long resting periods. As the average moisture content and the average particle temperature are estimated based on the spatial discretization used in the numerical solution, as well as on the boundary conditions adopted, the internal gradients of moisture and temperature are also estimated by the model, thus providing a physically consistent representation of the internal gradient behavior. Therefore, this study describes the successful application of an accurate model for continuous and intermittent drying. Accordingly, it contributes to obtain optimal drying parameters in order to minimize drying costs and improve product quality.

Evaluation of the German Angora Rabbit Fiber Produced in the Northeast Region of India

ABSTRACT The physical and mechanical properties of German Angora rabbit fiber obtained from the Northeast region of India were studied. The fiber fineness, staple length, diameter, and medullation of the overall fleece of the rabbit were 0.22 ± 0.04 tex, 09.10 ± 2.21 cm, 23.5 ± 1.04 µm, and 85.46 ± 1.23%, respectively. The cross-sectional shape was found elliptical to oval, and the average tenacity, breaking elongation, specific work of rupture, and initial modulus were 24.78 ± 11.48 cN/tex, 28.78 ± 09.06%, 3.46 ± 2.31cN/tex, and 1065.13 ± 826.67 cN/tex, respectively. The whiteness index average ash and moisture content were 61.24 ± 2.32, 1.36 ± 0.12, and 10.43 ± 0.57%, respectively. Three blend ratios of Angora rabbit fiber and viscose fiber (50:50, 25:75, and 0:100) were used to make yarns having 55 tex, 86 tex, and 97 tex linear density from each blend. Tenacity and breaking elongation significantly (p = .00) increased with an increase in the rabbit fiber composition in the blend and was maximum at the 50:50 blend (7.79 ± 1.92 cN/tex and 7.64 ± 1.70%, respectively). Yarn diameter increased with the increase in yarn count. With the decrease in the rabbit fiber composition from 50% to 25% in the yarn, the friction coefficient increased and the abrasion resistance decreased significantly (p = .00).

Numerical and experimental study on the heat and mass transfer of kiwifruit during vacuum freeze-drying process

In this work, the heat and mass transfer characteristics of kiwifruit samples during vacuum freeze-drying process have been investigated numerically and experimentally. The numerical simulation with moving grid method is adopted to simulate the radial and axial moving sublimation interfaces during vacuum freeze-drying. The simulated average moisture content and temperature of kiwifruit during drying are validated with the measured data, with the mean average error (MAE) of 14.7%. The findings demonstrate that the sublimation interface shifts toward the center during the drying process and the sublimation rate and pressure gradient are significant in the early stage of drying. After 10 h of drying process, the sublimation rate dropped by 80% due to the increase of the thickness of the dried region and the decrease of the shelf plate heat transfer. In addition, it is noted that the increasing shelf plate temperature and chamber pressure would cause an increase of sublimation rate, thereby reducing the drying time. Although increasing the sample thickness can improve the sublimation rate, the drying time becomes longer due to the presence of more ice crystals in thicker kiwifruit samples.

The physicochemical quality of yellow chrysanthemum flower (Chrysanthemum indicum) brewed drink

Chrysanthemum flowers (Chrysanthemums indicum) are processed into several products such as brewed drinks because they have good health benefits. The production process of commercial chrysanthemum flower brewed drinks still uses a conventional dryer with solar energy, this can reduce the quality of dried chrysanthemum flower both physical and chemical quality. Our objectives were to evaluate the chemical and physical quality of yellow chrysanthemum flower brewed drink by a cabinet dryer (CD). The materials used were fresh yellow chrysanthemum flowers with a moisture content of 83.00% (wb). The experimental design of this study used six treatments, including CD at 40°C, 50°C, 60°C, fresh flowers, and commercial chrysanthemum brewed drinks obtained from the market with storage of 1 day and 2 weeks. The parameters analyzed were moisture content, water activity, shrinkage, colour, antioxidant activity, total phenol, and sensory analysis. After evaluation demonstrated that the drying method using a CD at 60°C was the most optimal drying, with an average moisture content value of 15.18% (wb), the value of water activity is 0.25, shrinkage value for length and width, respectively 18.17% and 14.89%, the antioxidant activity of 87.67%, total phenol of 15.17%, and sensory evaluation results with the best formulation obtained in the sample with drying CD at 60°C.