Drying Time Research Articles

RANCANGAN PROTOTIPE MESIN PENGERING GABAH BERBASIS TEKNOLOGI HYBRID

Until now, the process of processing paddy into rice still relies heavily on the traditional and commonly used methods. During the drying stage, the harvested rice grains are spread out and sun dried. To address this issue, an effective solution is needed to enhance the quality of of rice seeds. Therefore, a post harvest rice handling technology is being developed with a hybrid technology based grain drying tool, where solar energy is still harnessed through photovoltaic solar panels (PLTS). The purpose of this research is to design, develop, and test a prototype grain drying machine abased on hybrid PLTS technology. The research focuses on calculating the power drying, and evaluating the PLTS system. The methods used include testing grain drying with variations in temperatures of 45ºC, 50ºC, dan 51ºC , as well as a grain weight of 8 kg. the greatest energy consumption during drying is directed towards the PLTS battery system, and calculations are performed to determine the duration of battery usage. The research findings reveal drying efficiencies of 9.7%, 12.8%, and 13.12% and final mouisture contents of 16.3%, 14.6% and 14.1 % at temperatures of 45ºC, 50ºC, and 51ºC respectively. The optimal drying times are 2 hours at 45ºC and 50ºC, and 1.5 hours at 51ºC. the battery usage time with a power of 209 W is 2.3 hours.

Effects of ultrasonic pretreatment and drying approaches on the drying kinetics and rehydration of sprouted mung beans

AbstractSprouting is one of the most traditional methods used to decrease most of the antinutritional elements in legumes. The assistance of ultrasound appears to enhance the drying step of the sprouted legumes. The aim of this study was to examine the influence of ultrasound pretreatment and drying methods (hot‐air and infrared) on the drying time, mass transfer kinetic, effective moisture diffusivity (Deff), and rehydration ratio of sprouted mung beans. The ultrasound process (40 kHz and 150 W) was performed in an ultrasonic bath for 0, 5, 10, 15, and 20 min. The results showed that the ultrasonic pretreatment increased the moisture diffusion capacity (higher moisture loss) and reduced the drying time of sprouted mung beans. Also, the drying time of samples in the infrared dryer was significantly less than that in the hot‐air dryer (p < .05). The Deff determined by Fick's second law was varied from 1.36 × 10−10 to 1.88 × 10−10 m2 s−1, and from 1.18 × 10−9 to 1.85 × 10−9 m2 s−1, for samples dried in hot‐air and infrared dryers, respectively. Comparing the coefficient of determination (r), sum of squared error (SSE), and root mean squared error (RMSE) values of 10 models, it was concluded that the Midilli model represents the drying characteristics of sprouted mung beans better than the others. The rehydration ratio of dried samples in hot‐air and infrared dryers increased when the ultrasound pretreatment time was increased. In general, the use of ultrasound pretreatment (about 20 min) and an infrared dryer is a promising drying technique for sprouted mung beans with higher mass transfer and a shorter drying time.

An Investigation of the Use of Microwaves and Airborne Ultrasound in the Convective Drying of Kale: Process Efficiency and Product Characteristics

This study evaluated different hybrid drying modes, combining traditional convective drying with microwave radiation and airborne ultrasound for the dehydration of green leafy vegetables. The central composite design method was used to analyze the impact of microwave and ultrasonic waves on kinetics, energy consumption, and various quality parameters, like color, ascorbic acid, polyphenol, carotenoid, and chlorophyll content in Brassica oleracea, var. acephala. The results of the applied experimental design, i.e., the surface response methodology, showed that the application of microwaves and ultrasound decreased the drying time considerably and enhanced the moisture evaporation from the kale leaves, significantly improving the drying rate and energy efficiency. The drying rate increase demonstrated varying results with changes in air temperature. Specifically, ultrasound resulted in a 69–100% increase, microwaves in a 430–698% increase, and a combination of ultrasound and microwaves in a 463–950% increase at 70 and 50 °C, respectively. Specific energy consumption decreased by 42–51% for ultrasound, 80–87% for microwaves, and 82–90% for ultrasound and microwaves at 70 and 50 °C, respectively. The drying parameters were also found to be better at a higher temperature, but the increase in the drying rate caused by microwaves and ultrasound was notably lower. Moreover, the analysis of the key kinetic parameters and material qualities led to the conclusion that the synergistic action of microwave- and ultrasound-assisted convection contributes to better drying effectiveness and product quality, demonstrating greater retention of vitamin C, phenolics, and natural dyes of up to 90%.

Preserving nutrient content in red cabbage juice powder via foam-mat hybrid microwave drying: Application in fortified functional pancakes.

Red cabbage, a highly nutritious cool-season cruciferous vegetable, is rich in anthocyanins; however, the instability of anthocyanins during processing and storage poses challenges. This study aimed to optimize the foam-mat drying process of red cabbage juice (RCJ) with a high anthocyanin content using a hybrid microwave hot air-drying system (MW-HAD) as a dehydration method compared to conventional techniques (HAD) using response surface methodology (RSM). Additionally, the produced red cabbage juice powder (RCJP) was used to enrich the pancake formulation. The developed model exhibited a high degree of reliability with optimal conditions and was determined for microwave power, temperature, foaming agent carboxymethylcellulose (CMC), and egg white protein (EWP) as 360 W, 60°C, 0.3%, and 1.2%, respectively. Moisture content (%) was decreased from 93.47 to 8.62 at optimum process conditions. In comparison to the control (60°C), foam mat drying with the MW-HAD hybrid system reduced the drying time (DT) by more than 90.9% due to the higher drying rate, while many physicochemical properties, especially total anthocyanin content (TAC), were better preserved. Utilization of RCJP in the production of anthocyanin-rich functional pancakes resulted in enhanced nutritional qualities compared to control pancakes with increased protein (35.07%), total phenolic (75.8%), dietary fiber (82.9%), and anthocyanin content (100%). In conclusion, MW-HAD demonstrates significant potential as a promising drying method to reduce the DT and preserve the physicochemical properties of RCJP. Furthermore, the application of the optimized RCJP in anthocyanin-rich functional pancakes highlights improved nutritional qualities, making a substantial contribution to the advancement of functional foods.

EFFECT OF DRYING TIME AND TEMPERATURE OF LPG FUEL CONSUMPTION DURING THE DRYING OF BAGE FISH TYPE TRAY DRAYER

Lemuru fish is a typical Sumbawa dish made from many types of fish and processed through various processes such as salting, salting and drying. The purpose of this research is the time and temperature of the drying process. The independent variables are: variations in temperature (50ºC, 60ºC, 70ºC) and time (180 minutes, 240 minutes, 300 minutes). After analysis, the following conclusions can be drawn. The drying speed is 180 minutes at 70°C. The highest drying speed was 0.98 g/minute, while the lowest was 300 minutes at 50 °C and a value of 0.56 g/minute. The air content temperature is 60⁰C and 70⁰C according to the quality standard for dried fish (SNI 82732016). Temperature 50 ⁰C 240 and time 300 minutes air content 32.67 n 28.33%. Drying time of 50% temperature 180 minutes gives 8.87% efficiency at lowest temperature 70ºC 300 minutes gives 3.64% The lowest material consumption is 180 minutes at 50ºC gives a value of 0.087 kg, the highest fuel consumption at 70ºC gets a value of 0.31 kg

Techno-economic analysis of a solar-assisted heat pump dryer for drying agricultural products.

Postharvest losses (PHLs) of biomaterials, such as vegetables and fruits, significantly impact food security and economic stability in developing nations. In Tanzania, PHLs are estimated to range between 30% and 40% for cereal crops and even higher for perishable crops such as fruits and vegetables. Open-sun drying (OSD) is the most extensively employed method because of its affordability and simplicity. However, OSD has several drawbacks, including difficulties in managing drying parameters, long drying times owing to adverse weather, and product contamination. The solar-assisted heat pump dryer (SAHPD) is a technology designed as an alternative solution for drying biomaterials and reducing PHL. A limited number of SAHPDs have been constructed in developing nations. Most of the works have concentrated on the performance analysis of the systems. This neglects the techno-economic assessment, which is important to provide both a quantitative and qualitative understanding of the financial viability of the technology. The present study therefore investigates the techno-economic analysis of a novel SAHPD for drying agricultural products, particularly vegetables and fruits. To determine whether the SAHPD technology is technically and economically viable, tomatoes and carrots were dried and analyzed to determine their thermal and economic performance. The results show that the initial moisture contents of tomatoes (Lycopersicum esculentum) and carrots (Daucus carota) were reduced from 93% and 88% to 10% in 11 and 12 h, respectively. The coefficient of performance (COP), drying time (DT), specific moisture extraction ration (SMER) and thermal efficiency () were found to be 3.4, 2.3 kg/h, 1.33 kg/kWh and 54.0%, respectively. The economic analysis was assessed using the annualized cost, lifecycle savings, and payback period for the dryer's life span of 15 years. The initial investment of the SAHPD was $5221.8 and the annualized cost was $1076.5. The cumulative present worth for 15 years was found to be $23,828.8 and $27,553.1 for tomatoes and carrots, respectively. The payback period for tomatoes was found to be 3 years, whereas for carrots it was 2.6 years. Based on thermal and economic performance assessment results, the developed SAHPD is technically and economically viable to be considered for further investments.

Development of acrylic based antimicrobial water‐based ink using curcumin for active packaging applications

AbstractThis experiment was conducted to formulate a water‐based ink with antimicrobial properties for packaging applications. Two distinct types of inks were developed, one with synthetic yellow color pigment and the other with curcumin, as an antimicrobial and a natural yellow pigment. The resulting two inks were then printed on polyethylene terephthalate (PET) films, and the physiochemical characteristics of the ink were thoroughly examined. The coated inks had an average thickness of 10 microns for both the inks. The viscosity of the water‐based ink and the antimicrobial water‐based ink were determined to be 54cp and 30cp, respectively and the drying time of the inks was 10 sec. At the same time, the gloss value increased from 30% to 50% in the case of antimicrobial ink. The antimicrobial efficacy of the antimicrobial water‐based ink, as demonstrated against S. aureus and E. coli, surpassed that of the conventional water‐based ink. These findings showed that the antimicrobial water‐based ink had a good drying time, increased gloss, and favorable storage stability. Using curcumin as a pigment in water‐based ink may be significant for printing applications of active food packaging materials. It can also help lower the risk of contamination of the food components with microbes.Highlights Synthesis of antimicrobial water‐based ink Active packaging printing Curcumin as an antimicrobial Curcumin used as a natural color pigment in the ink Acrylic resin synthesis

Defect-free asymmetric Matrimid® gas separation membranes using dihydrolevoglucosenone (Cyrene™) as a greener polar aprotic solvent than traditional solvents

Industrial membrane manufacturing via nonsolvent-induced phase separation (NIPS) generates large volumes of solvent-contaminated wastewater. An effective solution is to reduce the inherent toxicity of NIPS casting solutions, or dopes, by substituting traditional polar aprotic solvents with potentially benign alternatives such as dihydrolevoglucosenone (Cyrene™). This study demonstrates the reproducible preparation of high-flux defect-free asymmetric Matrimid® gas separation membranes via dry/wet NIPS using Cyrene™ as a majority dope formulation component. Defect-free membrane performance, as benchmarked for pure gas H2/N2 and O2/N2 separations, is maximized with high loadings of Cyrene™ relative to the volatile co-solvent tetrahydrofuran (THF) in casting solutions (volume ratios up to 3.20:1), which exceed the value of 1.68:1 used for Udel® polysulfone in our previous study. Cyrene™'s poor thermodynamic compatibility with the water coagulant and ability to produce highly viscous dopes ensure minimization and/or elimination of sublayer macrovoids while enabling defect-free membrane preparation at low (i.e., 12–14 wt %) Matrimid® and THF concentrations. Defect-free H2 permeance values up to 164 ± 14 GPU were achieved with a combination of high Cyrene™:THF volume ratios, low Matrimid® concentrations, and short dry step times (i.e., <15 s). Membrane performance achieved in this study matches or exceeds other literature reports of defect-free asymmetric Matrimid® membranes prepared with traditional NIPS solvents.

Kinetic analysis, mathematical modeling and quality evaluation of mint drying in greenhouse solar dryer

The goal of this study is to evaluate the potential of the Greenhouse Solar Dryer (GSD) for drying the mint leaves and compare it with other traditional drying methods. The top 10 mathematical models introduced by literatures were selected to describe the drying kinetics of mint leaves. The results showed that the average drying time in the GSD is 32 % and 50 % less than the open sun and shade place drying, respectively. Wang and Singh model with R2 = 0.9944, RMSE = 0.02021 and χ2 = 0.00052, logarithmic model with R2 = 0.9918, RMSE = 0.02556 and χ2 = 0.00078, and Henderson-Dabbie with model with R2 = 0.9774, RMSE = 0.04189 and χ2 = 0.00175 were determined as the best models for GSD, sun and shade place drying, respectively. The amount of changes in the color of the dried mint according to the index of total changes (ΔE) was recorded as 0.53 in the shade place, 0.60 in the GSD, and 0.89 in the open sun drying, respectively. The average of dried mint essential oil that was extracted by hydro-distillation method was 0.0254, 0.0237 and 0.0101 for shade place, GSD and open sun drying, respectively. Comparison of the average amount of extracted dried mint essential oil using ANOVA test, two LSD and Tukey HSD (Honestly Significant Difference) tests showed that there is no significant difference between the two treatments of drying in the shade place and GSD, while both of them have a significant difference with the open sun.

Tailoring surface and bulk morphologies to control transport properties of sulfonated block copolymer films

We examine the effects of solvent composition and solution-casting protocol on the structure of a lamellar sulfonated pentablock copolymer (SPC) membrane. Films are prepared by a layering process, wherein the film is built up through sequential bar-coating steps. Process variables include bar gap height, which controls drying time and layer thickness, and solvent selectivity toward each block in the SPC, which controls solution-state structure and biases the domain orientations at the surface. We find that irrespective of solvent selectivity, one-layer films have poorly ordered structures in the bulk with minimal restructuring near the surface. However, when the process involves sequential deposition of two or more layers, then the bulk structure of dry films can be well-predicted by the solution-state structure, and domain orientations at the surface are templated by polymer-solvent interactions. Consequently, processing conditions strongly influence through-plane transport properties of the SPC films. When the casting process generates disordered lamellae in bulk with a perpendicular lamellar orientation at the surface, both water and protons can move across the film. However, when the process generates highly ordered lamellae in bulk and parallel lamellar orientations at the surface, transport of both water and protons is inhibited by limited pathways. Significantly, the methodology outlined in this work can be extended to other ionic block copolymer platforms, allowing researchers to tailor bulk and surface morphologies for optimization of critical transport properties.

Moisture gradients in sawn timber during aggressive kiln drying investigated with X-ray computed tomography

ABSTRACT Reducing the time for drying sawn timber to a certain moisture level without deteriorating its quality is increasingly important for an economic and energy-efficient industrial timber-drying process and to support the transition to a sustainable society. It is, however, crucial to ensure that the quality of the timber, i.e. the degree of distortion, cracking, discolouration, and moisture variation within and between the pieces in a drying batch, is not compromised. Drying-simulation software tend to be too conservative in drying-rate recommendations, which has been observed in practise particularly for large cross-section timber of Norway spruce. This study investigated the drying rate and checking occurrence of centre-yielded Norway spruce planks when dried with more aggressive schedules than normally used in practise, i.e. using higher dry-bulb temperatures and/or lower relative humidities than recommended in the conventional optimisation programmes used in the sawmill industry in Sweden. The objective was to investigate the possibility to considerably reduce the total drying time without compromising the quality of the dried timber. The quality of the planks was indirectly assessed by estimating their moisture-content distributions, calculating the moisture gradients and monitoring checking. This was achieved with 4D (3D + time) X-ray computed tomography and a recently developed image processing algorithm based on elastic image registration. The key findings in this study suggest that Norway spruce timber can be dried with significantly higher temperatures and lower relative humidities than suggested by simulations, leading to reduced total drying time without inducing checking. This methodology can help to improve the design of drying schedules to reduce drying time and energy consumption while maintaining timber quality at a level accepted by the customers.

Effect of seawater dry-wet cycling on the durability of concrete repair materials

In order to investigate the durability of concrete repair materials in marine environments, this research selected four typical repair materials commonly used on the market to carry out indoor seawater dry and wet cycling tests and real marine environment exposure tests. The research results show that: the compressive strength and abrasion loss variations of these four repair materials under indoor seawater dry-wet cycling are closely related. Among them, magnesium phosphate mortar demonstrates better resistance to seawater erosion in both environments. The chloride ion penetration depth of four repair materials increases with seawater dry and wet cycling time. Its law of change is closely related to the law of change of the most probable pore size inside the material, while the epoxy resin mortar and acrylic-modified mortar have a high depth of chloride ion penetration under the real marine environment due to the microcracks and porous phenomena appearing on the surface of the material. In addition, the results of the tests in the real marine environment differed somewhat from those in the indoor environment, highlighting the need to conduct real marine environment tests. The results provide theoretical support for selecting and evaluating concrete repair materials in the marine environment.

INFLUENCE OF THE HEATING AGENT TEMPERATURE ON THE KINETICS OF THE CONVECTIVE DRYING PROCESS AND THE CONTENT OF BIOACTIVE COMPOUNDS IN APPLE POMACE

An environmentally ecological approach to the reuse of agro-industrial products in the food industry involves extracting biologically active substances or using them as supplementary products rich in dietary fibers. Apple pomace obtained after juice extraction presents a product rich in biologically active substances, soluble and insoluble fibers, organic acids, and minerals. Convective drying of apple pomace is an alternative method for long-term preservation by maintaining the biologically active substances. The research aimed to study the influence of temperature in the range of 60-80 °C on the drying of apple pomace to a final moisture content of 12.0±0.13% using the convective method, and the effect of temperature on the yield of bioactive compounds and antioxidant activity in Gold Delicious apple pomace. Changing the air temperature during convective drying from 60 to 80 °C reduced the drying time by 1.6 times and demonstrated a 1.4-fold increase in drying rate. The increase in the thermal agent's temperature led to an increase in the kinetic characteristic values; KI values increased by 4%, and KII values increased by 44%. Spectrophotometric analysis demonstrated that apple pomace dried at a temperature of 70 °C had the highest total content of polyphenols, tannins, and carotenoids. Thus, the convective drying method of apple pomace in the temperature range of 60-80 °C exerts a significant influence on the composition of biologically active compounds in the apple pomace composition.

Spatiotemporal distribution of precipitation and its characteristics under tropical atmospheric systems of Brazil: Insights from a large sub‐hourly database

AbstractThe study of rainfall properties at various spatiotemporal scales is deeply important for understanding a large range of socio‐environmental processes and variables (e.g., water resources, agriculture, socio‐ecosystemic services, natural risk assessment). However, such studies on rainfall characteristics, especially at sub‐hourly resolutions, are scarce in large areas of South America due to the lack of a high‐resolution temporal database. The Brazilian National Centre for Monitoring and Early Warning of Natural Disasters (CEMADEN) has gradually implemented, starting in 2013, a sub‐hourly monitoring network composed of approximately 3500 automated rain gauges distributed across Brazil, enabling access to new hydrological studies in this vast tropical country featuring a range of biomes. This study analysed the characteristics of rainfall events for the whole of Brazil on sub‐daily and sub‐hourly timescales, using 7 years of data (from 2014 to 2021) provided by CEMADEN. Rainfall events were defined by the minimum inter‐event time (MIT) and the minimum depth (1 mm). Seven MITs (30, 60, 120, 180, 360, 720, and 1440 min) were considered to evaluate the behaviour of rainfall event characteristics and their relationships. The Gaussian mixture model method was applied to identify regions with similar rainfall patterns according to the MIT. Six groups with homogeneous characteristics were identified, evidencing the climatic diversity of Brazil. The results show that the MIT strongly influences precipitation properties (especially the dry time and the number of events). The highest number of events occurred in the North‐east Coast region, which exceeded 200 events per year (MIT &lt; 60 min), while the lowest number of events was observed in the Semiarid region, which reached only 38 events per year with an MIT of 1440 min. Moreover, the events with the highest rainfall intensities were found in the Central region. The results found in this study provide a better understanding of precipitation and its characteristics in Brazil, highlighting the climatological diversity of this country.

FORMULASI DAN EVALUASI KESTABILAN FISIK SEDIAAN MASKER GEL PEEL-OFF DARI SARI BUAH LEMON CUI (Citrus microcarpa Bunge.)

Lemon cui also known as fish lemon or kalamansi lemon is known to contain one of them vitamin C which has the potential as an antioxidant so that it can be applied as active ingredient in peel off mask preparations. The aims of this study weretoobtaining the best PVA concentration in the manufacture of peel-off gel masks from lemon cui juice that meet the stability test requirements. physique. The method of making a sample of lemon cui juice is obtained by grinding it using a blender, adding 100 mL of water and then separating the pulp to obtain the juice. The formulation of peel-off gel mask preparations uses variations in the concentration of PVA (Polyvinyl Alcohol), namely F1 (10%), F2 (13%) and F3 (16%). Physical stability tests included organoleptic tests, homogeneity tests, spreadability tests, pH tests, adhesion tests and drying time tests.The results showed that the preparations F1, F2 and F3 showed physical stability based on the results of organoleptic tests, homogeneity tests, spreadability tests, pH tests, adhesion tests and drying time tests before and after accelerated storage conditions. Based on the test results obtained, it can be concluded that the formulation of the Lemon Cui peel-off gel mask preparation from the three concentrations of PVA met the requirements for physical stability. The best PVA concentration is 10% because it has the best dry time.

МОДЕРНИЗАЦИЯ ГРЕБНЕОБРАЗОВАТЕЛЯ ДЛЯ ВОЗДЕЛЫВАНИЯ КАРТОФЕЛЯ

The conditions for watering potatoes when cultivating them on ridges have been tested and justified. The KG-2.8 ridge former cultivator was modernized to form a ridge of the specified parameters. In addition to the ridge-forming cultivator, a groove former was installed on each row to form a groove on the upper part of the ridge of a trapezoidal shape, capable of effectively retaining water during irrigation or rain and wetting the entire volume of the ridge. The groove maker has a trapezoidal roller, which is made with the ability to remove and install it on the ridge former body along the axis of the row of planted potatoes. It has been established that with the traditional shape of the ridge, when watering potatoes at an air temperature of more than 300C, intense drying of the soil occurs due to the fact that a significant part of the water simply flows into the aisle and does not have time to completely wet it. And after it begins to flow down the rows, watering is stopped. This drying leads to the fact that soil moisture after irrigation at a rate of 250 m3/ha in the area where the root system and potato tubers are located decreases in 4-5 days to a maximum humidity of 20%, at which the growth of tubers stops. It has been established that the use of a groove former together with a ridge former makes it possible to create conditions for the accumulation of water in a groove on the ridge and its subsequent filtration inside, to prevent the flow of water between rows and to create conditions for the exclusion of water runoff. Intensive wetting of the entire volume of soil in the ridge allows you to increase its drying time to 8 days, which will significantly reduce costs.

ИССЛЕДОВАНИЕ УСТАНОВКИ С ИНФРАКРАСНЫМ НАГРЕВОМ ЗЕРНА

Thermal post-harvest processing of grain currently intended to improve its quality is highly energy-intensive and expensive. The development of new means of mechanization with infrared heating of grain, capable of reducing specific energy costs for heat treatment processes, as well as ensuring resource conservation, is a pressing and important scientific and technical problem. To reduce the cost of drying, disinfection and micronization of grain, as well as improve the quality of its heat treatment, we have developed an experimental model of an installation with infrared heating. The study of the developed installation was carried out in grain drying mode. The technological process of drying wheat grain with an initial moisture content of 18...19% was chosen as the object of study. The total specific energy consumption for grain drying was taken as an optimization parameter. The rational values of the selected factors were determined as a result of a study of the developed installation with infrared heating of grain: grain drying time t1 = 1000C; the temperature created by the infrared heater inside the installation casing is tin = 650C. Next, a series of experiments was carried out on the developed installation in the above modes. In each experiment, measurements were taken of the heating temperature of the grain, the percentage of reduction in grain moisture content and the throughput of the installation were determined, and the total specific energy consumption was recorded. The heating temperature of the grain was in the range of 37 - 38.5 ºС, while the moisture content of the grain decreased by 2.56%. The developed installation provides the required quality of grain drying, maintaining a throughput of about 800 kg/h and a minimum total specific energy consumption, which amounted to 4342.3 kJ h/kg.

Effects of ultrasound and microwave pretreatments of carrot slices before drying on the color indexes and drying rate

The aim of this study was to examine the impacts of microwave pretreatment (MWP) and ultrasonic pretreatment (USP) on drying time (DT), mass transfer kinetics, effective water diffusivity (Deff), rehydration rate, color index (L*, a*, b*), and the surface shrinkage of carrot slices when dried in a hot air dryer (70 °C). The microwave process was performed for 0, 15, 30, 45, and 60 s before drying of carrot slices. In addition, the ultrasound process was performed in an ultrasonic bath (40 kHz and 150 W) for 0, 5, 10, 15, and 20 min. The results confirmed that the MWP and USP decreased the DT (higher water loss) of carrot slices. Deff values for microwave-pretreated slices were considerably higher than those for nontreated carrot slices (p < 0.05). The Deff calculated by Fick's second law was increased from 8.69 × 10−10 to 10.96 × 10−10 m2 s−1, and from 7.56 × 10−10 to 9.39 × 10−10 m2 s−1, for samples pretreated by microwave and ultrasound, respectively. The empirical value for the drying curves were fitted to the common thin film-equations, and Page's equation was the most suitable to describe the dehydration rate of carrot slices. The average rehydration ratio of nontreated, microwave-treated, and ultrasound-treated carrot slices were 432.3 %, 449.2 %, and 360.9 %, respectively. The redness, yellowness, and surface shrinkage parameters of pretreated samples by microwave were higher than the nontreated slices. The lightness and redness parameters of pretreated carrot slices by ultrasound were higher than the nontreated samples under all conditions.

Effect of individual factors on the extraction of phenolic compounds from turmeric rhizomes (Curcuma longa) and moringa leaves (Moringa oleifera

Phenolic compounds are of great interest for their high antioxidant power and their numerous health benefits. These biomolecules are present in large quantities in many food and medicinal plants, such as the rhizomes of Curcuma longa and the leaves of Moringa oleifera. However, extraction methods for these bioactive compounds underestimate the plant's potential. The aim of this study was therefore to evaluate the influence of seven factors involved in the process of extracting phenolic compounds from Curcuma longa rhizomes and Moringa oleifera leaves. The seven main factors, i.e. drying time, mesh size, ethanol concentration, solvent/sample ratio, stirring speed, temperature and extraction time, influence the extraction of total polyphenols from Curcuma longa rhizomes and Moringa oleifera leaves. However, the optimum conditions for sample drying time are 48 to 72 h for Curcuma longa rhizomes and 60 to 72 h for Moringa oleifera leaves. Those for mesh size and sample/solvent ratio are 250 to 500 µm and 1/20 to 1/10 respectively. The best solvent concentration was between 60 and 80% for Curcuma longa rhizomes and between 40 and 60% for Moringa oleifera leaves. In addition, the best stirring speed is between 200 and 300 rpm and the best extraction time between 15 and 30 min. In addition, the best extraction temperatures are between 40 and 50°C for Curcuma longa rhizomes and between 50 and 60°C for Moringa oleifera leaves. These factors should therefore be taken into account for maximum extraction of total polyphenols from Curcuma longa rhizomes and Moringa oleifera leaves.

Physicochemical Characteristics of Carrot Chips (Dried Slices) with Differences in Temperature and Drying Time

Carrots are one of the vegetable commodities that are rich in nutrients. This research is about drying carrots to extend the shelf life of vegetable products and maintain the nutritional content contained in carrots. Carrots are dried to produce a product like nutritious carrot chips. This research uses vacuum oven drying with different temperatures and drying times to determine the correct temperature and drying time to maintain carrot chips' nutritional content and physical appearance. The research design was a Completely Randomized Design (CRD) with two factors, namely drying temperature (50°C, 60°C, 70°C) and drying time (6 hours, 8 hours, 10 hours). Carrot chips with different temperatures and drying times significantly affected water content, total carotene, color index, and texture. Carrot chip products with vacuum oven drying at 60°C for 10 hours gave results with a water content of 4.24%, the highest total carotene value of 57.15 mg/100g, color appearance with an L* index of 35.68, a * of 20.91, b* of 17.63, texture value of 281.65 N/m2. As well as having organoleptic test results that were liked by the panelists regarding the color and texture of the carrot chips.