Cabinet Dryer Research Articles

Phytochemical composition, antioxidant activities and anti‐obesity potential of selected vegetables as affected by drying methods

AbstractObesity has reached epidemic statistics worldwide and there is an urgent need to explore more available options in addressing the condition. The potential of vegetables as natural sources of enzyme inhibitors that can regulate the progression of obesity is of great interest particularly due to possible synergistic antioxidant activities. In this study, we evaluated the phytochemical composition, antioxidant activities, and in vitro enzyme inhibition properties of selected vegetables as influenced by sun and cabinet drying methods. While a significant increase was observed in the phytochemical composition of most of the vegetables, the two drying methods had varying effects on all parameters. Cabinet drying yielded higher saponin (2.86–4.67 mg/100 g), phenolics (19.30–57.02 mg/100 g), and alkaloids (31.58–37.61 mg/100 g) contents while sun drying gave better results for flavonoids (88.13–234.15 mg/100 g). The DPPH (11.45%–29.61%) and ABTS (22.70%–35.48%) antioxidant activities varied significantly. Cabinet‐dried cabbage and sun dried carrot flours displayed the highest inhibition against alpha amylase and pancreatic lipase, respectively. A strong positive correlation was observed between phenolics and amylase inhibition and also between saponin and pancreatic lipase inhibition. Consequently, vegetable flours could serve as versatile products for the therapeutic management of obesity and related diseases.

Development of a top-lit-up-draft biomass gasifier as a sustainable heat source for effective drying of plantain slices in a cabinet dryer

This paper explored the development of a top-lit-up-draft biomass gasifier as a sustainable heat energy alternative to the traditional sun drying and the costly, unreliable heat energy sources such as grid-electricity and petrochemical fuels commonly used for cabinet dryers, especially in developing countries like Nigeria. The gasifier utilized the principle of top-lit-updraft biomass gasification system to thermochemically converts agricultural residues into clean heat energy. The designed gasifier has reactor diameter and height of 28cm and 90cm, fuel consumption rate of 55kg/hr, gasification airflow rate of 82.1m3/hr, DC fan motor of 15W, equipped with 30Ah battery power source, and capable of supplying heat energy of 260.16MJ/h. Performance testing using input variables of fuel loading (10kg-20kg), fan speed (4000rpm-6000rpm), and fuel type (palm-kernel shell, coconut shell, coconut husk, and wood shavings) assessed the gasifier responses such as fuel gasification time, flame temperature, thermal and combustion efficiencies, and carbon monoxide (CO) emission of the flame. Results revealed maximum thermal efficiency, peak flame temperature and longest gasification time of 86.02%, 8750C, and 130min respectively, when operated with palm-kernel shell at maximum fan speed and fuel loading, which emitted average CO of 1ppm lower than the least international air pollutant threshold of 9ppm. Highest combustion efficiency of 99.9% was attained using wood shavings at maximum fan speed and fuel loading. The results highlighted the potential of the gasifier as an effective heat source for drying applications, particularly for drying plantain slices in a cabinet dryer.

Physicochemical and functional characteristics of egg white powder as affected by pre-treatment and drying methods

Egg white is often regarded as a high-quality protein source that contains all essential amino acids required by humans. A fresh egg in liquid form has a short shelf life, thus drying it into powder can be the best alternative for a longer short life. This research aimed to evaluate the physicochemical and functional characteristics of egg white powder (EWP) as affected by pasteurization as pre-treatment and drying methods. There were six treatments in the preparation of EWP, i.e., pasteurization, unpasteurization and combined with three drying methods (spray-, cabinet-, or freeze-drying). The physical and functional properties of EWP were determined i.e., the yield, color, water activity, bulk density, flowability, foaming, emulsification, water absorption (WAC), oil absorption capacity (OAC), and gel strength. The chemical properties i.e. moisture content, fat, ash, protein content, protein digestibility, and antioxidant activity were also determined. The results showed that pasteurization and different drying methods affected the physicochemical and functionality of EWP. Pasteurization treatment significantly increased the bulk density of EWP prepared by spray- and cabinet drying, WAC of EWP prepared by spray- and cabinet drying, gel strength of EWP prepared by spray drying, the protein content of EWP prepared by spray drying, protein digestibility of EWP prepared by spray- and cabinet drying; however, significantly decreased the aerated and tapped bulk density of EWP prepared by freeze-drying, gel strength of EWP prepared by cabinet- and freeze-drying, the protein content of EWP prepared by cabinet- and freeze-drying, protein digestibility of EWP prepared by freeze-drying, antioxidant activity of EWP prepared by spray-, cabinet-, and freeze-drying. Different drying methods significantly affected the color parameters, bulk density, gel strength, moisture content, protein content and protein digestibility. This study suggested that the best characteristic of EWP was that of unpasteurized and prepared by freeze-drying method.

Brazilin Content, Color Stability, and Antioxidant Activity of Sappan Wood (Caesalpinia Sappan L.) Traditional Drink by Different Blanching and Drying Methods

Caesalpinia sappan L (CS) heartwood is used as a natural red colorant in several Asian ethnic traditional drinks both as sole ingredient or mixed with other herbs. However, the pigment is unstable and easily degraded during storage which affects consumer acceptance. This research aimed to investigate the effect of different blanching and drying methods on the color stability, brazilin content, and antioxidant activity of CS heartwood drinks. Steam blanching, water blanching, sun drying and cabinet drying were examined in this study. The most common method applied in traditional production, without blanching and sun drying, was used as a control. The experimental design used was complete randomized design with triplicates. Data are presented as mean ± standard deviation and analyzed by SPSS statistics version 20. The results showed that blanching and drying methods affected the color intensity. For a pure CS heartwood herbal drink, the sample prepared with water blanching and cabinet drying (BCD) showed the highest red value, leading to a 48 % improvement compared to the control. This red value is in accordance with the brazilin content. Sample BCD showed the highest brazilin content, which was 376 % higher than that of the control. Similarly, the BCD sample had the highest antioxidant activity and total phenolic content, with IC50 values of 98.99 ppm and 213.12 mg GAE g–1, respectively. This result revealed that brazilin might act as an antioxidant. Similar to the pure CS drink, the highest quality of mixed herbal drink was obtained by BCD sample. The results suggest that the combination of water blanching and cabinet drying (BCD) was the best method to improves the quality of CS heartwood drink both in pure and mixed herbal drinks as a functional drink. HIGHLIGHTS Samples treated with blanching and drying had higher brazilin content of Sappan heartwood drink There is a correlation between brazilin content and color intensity as well as antioxidant activity Blanching and cabinet drying improved the color stability of Sappan heartwood drink Blanching and cabinet drying increased the total phenolic and flavonoid content of Sappan heartwood drink GRAPHICAL ABSTRACT

Comparative Study on Calcium-enriched Finger Millet Tisane: Optimizing Soaking and Roasting Methods

This study focuses on the development of a calcium-rich herbal tisane using finger millet, a grain known for its high calcium content, aimed at enhancing dietary calcium intake. Two distinct processing methods were employed to optimize the calcium content of the tisane. In Treatment 1, Finger millet was roasted and combined with spice powder, while in Treatment 2, Finger millet underwent soaking, cabinet drying, roasting, and then blending with spice powder. The calcium content and overall quality of both treatments were evaluated, revealing a marginal increase in calcium concentration in Treatment 2, attributed to the additional processing steps. Specifically, Treatment 2 yielded a maximum calcium content of 396 mg compared to 380 mg in Treatment 1, demonstrating the effectiveness of the additional soaking and drying steps in enhancing calcium bioavailability. The final product was further enriched with a blend of spices, including dry ginger, cinnamon, cardamom, Arjuna bark, fennel seeds, and Tulsi leaves, contributing to its healthful properties. Organoleptic evaluations, conducted to assess sensory attributes such as flavor, aroma, and overall acceptability, indicated that both treatments were well-received by consumers. This suggests the product's potential for consumer acceptance and market viability. The findings suggest that calcium-enriched Finger millet tisane could serve as a valuable functional beverage, particularly for populations at risk of calcium deficiency. Its nutrient profile, combined with favorable sensory attributes, positions it as a promising option for improving dietary calcium intake and promoting overall health. Further research on larger sample sizes and bioavailability studies could reinforce its potential as a functional health beverage.

Aspek Gizi dan Fungsional Tepung Bawang Dayak (Eleutherine palmifolia (L) Merr) : Kajian Pengeringan Menggunakan Fluid Bed dan Cabinet Dryer

Dayak onion is a type of medicinal plant that grows in several areas and has been used for generations to cure various diseases in Kalimantan, Indonesia. Dayak onion contains bioactive compounds such as phenolic, flavonoids, saponins, tannins and naphtoquinones which can act as antioxidants, anti-microbials, and anti-inflammatories. Currently the application of Dayak onions is still rare even though it has many benefits. This study aims to characterize nutritional and functional aspects of dayak onion flour with various drying temperature using fluidized bed dan cabinet dryer. The research design used is factorial design. The characterization of Dayak onion flour carried out was yield, moisture content, ash, protein, fat, concentration of IC50, WHC and OHC. Microbial contamination tests carried out included ALT, E.coli, and mold. In the research results, the best nutrition and functional aspect of Dayak onion flour was drying with temperature 40? in the cabinet and fluidized bed dryer. Determination of the best results is taken based on the De Garmo test where the two samples have the highest value of effectiveness in each method. The best concentration of IC50 is Dayak onion flour using the cabinet dryer with a temperature of 35? that was 3703,43 ppm. In addition, no growth of E.coli and mold bacteria was found and the number of bacterial colonies was still classified as safe when compared to the SNI for cassava flour so that dayak onion flour was safe against microbial contamination.

Optimizing the drying process with the surface response method for snap beans, sweet corn, and carrots

Abstract Vegetables contain many nutrients that are susceptible to loss when dried. Pre-treatment is needed to reduce nutrient loss during drying. This research aims to determine optimal pre-treatment and drying conditions for dried vegetables. Optimization using the D-optimal response surface method for snap beans, carrots, and sweet corn. The optimized process conditions are drying temperature (45°C, 50°C, 55°C); blanching technique at 75°C (immersion, steaming); freezing treatment (with freezing -20°C 24 hours, without freezing); and type of dryer (cabinet dryer, dehydrator). The research results show that immersion blanching (75°C), freezing (-20°C, 24 hours), and cabinet dryer type at 50°C are the best conditions for processing dried snap beans. The best method for drying sweet corn is immersion blanching (75°C), freezing (-20°C, 24 hours), and drying in a dehydrator-type drying at 50°C. Immersion blanching (75°C), freezing (-20°C, 24 hours), and dehydrator-type dryer at 55°C are the best methods for drying carrots.

Comprehensive assessment of drying performance, physical characteristics, bioactive compounds, and antioxidant capacity of mallow (Malva verticillata) vegetables: A comparative study of a modified tray dryer and conventional drying methods

Drying vegetables in a suitable dryer is an imperative concern in the food-processing sector. To address this issue, a cabinet-type tray dryer has been developed by modifying its design, employing a comprehensive approach ensuring uniform air velocity and temperature in all the trays, and naming it a modified tray dryer (MTD). A comparative analysis of drying performance, physical characteristics, functional attributes, and antioxidant capacity of mallow (Malva verticillata) vegetables dried in MTD and existing three drying methods such as sun, shade, and traditional cabinet drying was accomplished. The performance evaluation study revealed that MTD demonstrated a faster moisture removal capacity and required less drying time compared to other drying methods. Statistical analysis revealed that drying methods had a significant (p < 0.05) impact on the physical properties, functional qualities, and bioactive functions of the dried mallow powder (MP). The higher chlorophyll content (27.41 ± 0.84 mg/100 gm of dry matter, DM), total phenol content (15.71 ± 0.95 mg GAE/g DM), and DPPH activity (8.82 ± 0.81 mg TEAC/g DM) were noticed in the mallow vegetable powder dried in MTD than shade, sun and traditional cabinet drying methods. A slightly lower value (statistically insignificant) of ascorbic acid content (9.64 ± 0.78 mg/100 gm DM) and total flavonoid (1.44 ± 0.05 mg QE/g DM) was achieved in contrast to other drying methods. The antioxidant capacity of the analyzed data was lowest for shade drying compared to other drying methods, while MTD exhibited the highest capacity. Therefore, this study might assist in selecting a suitable dryer for drying vegetables. The findings suggest that MTD can be an alternative drying technique as a quicker drying technique and for obtaining better-quality dried products in terms of antioxidant and functional properties than the traditional and existing process of vegetable drying.

A new synergistic hydrocolloid with superior rheology: Locust bean /xanthan gum binary solution powdered by different drying methods

In the current study, a novel gum powder containing locust bean and xanthan gums was prepared by three different drying methods of their synergistic aqueous solutions: direct cabinet drying (CD), drying after alcohol precipitation (PD), and direct freeze drying (FD). The purpose of this process is to develop ready-to-use synergistic gum powders with improved rheological properties by modifying intermolecular interactions. Significant improvements in viscosity, consistency efficiency and pseudoplastic character were observed for PD, followed by CD and FD, as well as the higher values of G′ and G″ values of PD, indicating a stronger entanglement network development between the macromolecules for PD. PD exhibited better elasticity and shear resistance compared to FD and CD in the strain sweep test. In Lissajous curves, straight line shapes were found for synergistic solutions at low strain, which continued for increasing strain values for PD and CD. However, the pronounced viscous behavior was found for FD at 500% strain. Compared to CD and FD, PD exhibited a more desirable thixotropic character. A lower zeta potential was observed in the production of synergistic gums using the PD process. Gel strength was found to be higher for PD. Therefore, PD was a more effective method to produce a ready-to-use synergistic powder with better viscoelastic properties and a more stable solution.

Effects of Different Solvents on the Antioxidant Activity of Several Seaweed Species from Semporna, Sabah, Malaysia

Sabah is the main seaweed producer in Malaysia especially red seaweeds which are commercially cultivated for the production of food gum known as carrageenan. Seaweeds are also high in phytochemical such as antioxidant compounds. Three seaweeds species from the Semporna Seawater, Sabah, namely Kappaphycus alvarezii, Caulerpa lentillifera and Sargassum polycystum were chosen for this study for the analysis of their antioxidant activities. K. alvarezii species is commercially cultivated whereas the other two (C. lentillifera and S. polycystum) are wild species. All seaweeds species underwent drying process in a cabinet dryer prior to the analyses. Six types of solvents which were water, ethanol, methanol, chloroform, ethyl acetate and hexane were used for the extraction process. Every concentrated, extracted solutions were then measured for their antioxidant activities based on total phenolic content (TPC), diphenylpicrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP) and β-carotene bleaching assay. Results showed that TPC of S. polycystum was significantly higher (p&lt;0.05) than K. alvarezii but not significantly different (P&gt;0.05) from C. lentillifera. Even though the extraction yield of water was the highest, but the greatest antioxidant activity values were seen in methanolic extraction in comparison to the other solvents in TPC, DPPH and FRAP. This indicated that most of the antioxidant compounds in all the three seaweed samples are polar. However, high antioxidant activity in terms of β-carotene bleaching assay were seen in other solvent extractions, which were chloroform, hexane and ethyl acetate. This indicated that seaweed also contain non-polar antioxidant compounds such as β-carotene. Overall, the best extraction method of antioxidant compounds in seaweed samples was using methanol as the extractant.

Development of Coconut Protein Concentrate-Xanthan Gum Conjugate by Wet-Dry Heating Method for Red Palm Oil Emulsification

Protein-polysaccharide conjugation is commonly achieved by wet and dry heating methods. Therefore, this study aimed to produce red palm oil (RPO) emulsifiers by conjugating coconut protein concentrate (CPC) and xanthan gum (XG) through a combination of wet and dry heating method using a cabinet dryer. Several factors, including reaction time (3, 4, 5, 6, and 7 hours), pH (3, 5, 7, 9, and 11), and protein-polysaccharide ratio (1:3, 1:2, 1:1, 2:1, and 3:1) were evaluated for their effect on the Emulsion Activity Index (EAI) and Emulsion Stability Index (ESI). The ability of the obtaining conjugate to emulsify RPO was evaluated, and the results showed that CPC contained 67.40% protein. Reaction time, pH, and protein-XG ratio had a significant effect on EAI and ESI. Meanwhile, optimal conditions for the formation of the CPC-XG conjugate, based on EAI and ESI, were a reaction time of 5 hours, pH 9, and protein-polysaccharide ratio of 2:1. Fourier Transform Infrared (FTIR) analysis showed that the CPC-XG conjugate had a change in absorption at a wavelength number of around 1640 cm -1 , indicating the presence of a Maillard reaction product. Furthermore, the CPC-XG conjugate used in RPO emulsion has a characteristic EAI value of 23.74 m 2 /g, ESI of 271.32 minutes, a droplet size of 790 nm, and a zeta potential of -36.9 mV. These results suggest that the CPC-XG conjugate produced by the wet-dry heating method has the potential for producing stable RPO emulsions.

A Study on Isolation of Fibre from Red Cabbage to Enhance Athletic Performance

Achieving peak performance in sports is a multifaceted process that goes beyond training and skill development. Nutrition, particularly dietary fiber, is a crucial aspect often overlooked in this pursuit. Fiber, a complex carbohydrate found in plant-based foods, is essential for the overall health and performance of sports people. Red cabbage, also known as purple cabbage, is a nutritious vegetable with antioxidant properties. It is rich in vitamins C and K, dietary fiber, and supports gut health by nourishing gut bacteria, enhancing digestion, and reducing inflammation. Two samples of red cabbage were dried: one sample was sun-dried for 3 days, and the other sample was dried in a cabinet dryer at 9 ° C for 8 hours. The results indicated that the sample dried in the cabinet dryer showed high fiber content, and the isolation of fiber was done in this sample. This study contributes valuable insights into maximizing the nutritional benefits of red cabbage and finger millet to enhance sports performance of the sports person.

Pengaruh Lama Pengeringan Cabinet Drying Terhadap Karakteristik Kimia dan Organoleptik Manisan Kering Pala Banda

The research aimed to determine the proper drying time to produce dried sweets banda nutmeg with the best chemical and organoleptic properties. This study used a completely randomized design with one factorial with four treatment levels: sun drying, drying cabinet dryer 18, 19, and 20 hours. The parameters analyzed were chemical tests (moisture content, ash content, and total sugar) and organoleptic tests (color, aroma, taste, texture, overall). The results showed that treatment with a drying time of 18 hours produced the best-sweets banda nutmeg with chemical characteristics of 11.44% water content, 0.84% ​​ash content, 45.89% total sugar, and based on the hedonic organoleptic test showed like color (3 .20), liking (3.04), liking texture (3.08). In contrast, for hedonic quality, it offers a brown-yellow color (2.48), nutmeg flavor (3.36), and slightly chewy texture (2.16 ).

Development and performance assessment of a hybrid solar cabinet dryer for fish drying

The fish products can be stored for longer period in dry condition, but most of the fresh fish in remote areas of our country are spoils due to lack of proper preservation. To overcome this problem, hybrid solar dryer can play an important role to make drying continuous during night and daytime also off sunshine hours. In this project, a hybrid solar cabinet dryer has been designed, constructed, and performance tested for fish drying. The dryer consists of a drying chamber, solar collector, two trays of dimensions (60×60) cm and paraffin wax as PCM. It also consists of photovoltaic cell modules, heating element, electric battery, and other electric equipment such as inlet and outlet fans. The dryer has been operated as both a solar energy dryer during normal sunny days and a hybrid solar dryer during cloudy days. Paraffin wax system inside drying chamber absorbed heat energy in Sunny time. At the same time the battery is charged from the solar system and therefore the water kept in the tank reaches a certain temperature by absorbing heat from nature, which provides heat by circulating the water inside the drying chamber during inclement weather. Electric fans are used at the inlet of the solar collector and outlet of the dryer to maintain adequate air flow inside the drying chamber. During the night and cloudy weather paraffin wax and heater system deliver heat to maintain the set temperature in drying chamber. The grain bed in the dryer is heated by air that comes from a separate solar collector, and at the same time, the drying cabinet collects solar energy directly through the transparent walls and roof. The dryer demonstrated the capacity to dry fish to an appropriate moisture level in a reasonable amount of time, and concurrently, it insured that the fish would be of high quality. The drying rate of hybrid solar dryers is evaluated on fresh fish and compared with solar dryers and sun drying under the same climatic conditions.

Effect of Drying Methods on the Moisture Content and Microbiological Properties of Three Varieties of Dried Onion Slices (Allium cepa)

Post-Harvest losses of onions occurring due to poor handlings and spoilage by microorganisms is worthy of concern. Value addition through drying during peak seasons can reduce losses remarkably. This study sought to evaluate the effects of different drying methods on the microbial load of dried onion slices. Three varieties of onion (red, white and cream) were purchased National Institute for Horticultural Research (NIHORT) Kano sub-station and processed into dried slices using three dryers namely; Solar Cabinet Dryer (SCD), Electric Powered Dryer (EPD) and Kerosene Powered Dryer (KPD) at three different temperatures (50, 60 and 70oC). The dried onion slices were then evaluated for their microbial load; Aerobic Plate Counts (APC), Coliform Counts (CC) and Fungal Counts (FC) using three different media and according to standard methods. The results revealed that MC of onions were reduced from 88.29% to as low as 5.19% during drying. The APC, CC and FC of red onion ranged from 3.67–5.39×102 cfu/g, 1.35–5.39×102 cfu/g and 3.44–4.83×102 cfu/g respectively. The load for white onion ranged from 3.11–5.19×102 cfu/g, 1.31–5.29×102 cfu/g and 3.43–4.53×102 cfu/g respectively while that of cream onion ranged from 3.30–5.33×102 cfu/g, 1.33–5.39×102 cfu/g and 3.42–4.57×102 cfu/g respectively. All the readings fell below the international recommended safe limit for food consumption. The EPD samples at 60oC and 70oC had the significant lowest (p≤0.05) fungal counts in all the onion varieties. Therefore, electric oven dryer at 70oC was the best drying methods and temperature for onion for long time storage.

Performance Evaluation of a Hot-Air Groundnut Cabinet Dryer

Groundnut, also known as peanut, is an important source of food and oil, with the seeds being high in protein, fibre, and healthy unsaturated fats which are consumed in large quantities in most parts of the sub-Saharan Africa and the world at large. The post-harvest processing of peanut, most-especially drying that involves dehydrating the crop to safe moisture content for home and commercial purposes still need more attention as local drying prevailed in the country. An existing hot-air cabinet dryer was improved and evaluated for the drying of peanuts under the humid rainforest climate of Akure, Nigeria. The dryer was tested using three varieties of groundnut (red, white and kampala varieties), three drying air temperatures of 400C, 500C and 600C, two drying air velocities of 1.67 m/s and 2.78 m/s and two product loadings of 3 kg and 4.5 kg per batch. The thermal efficiency, drying rate, drying time and moisture loss were determined as the evaluation parameters of the dryer. The evaluation conducted revealed thermal efficiency range of 46% – 96% with average thermal efficiency of 71.31%. The drying rate of the dryer ranges from 0.36 kg/h – 0.21 kg/h, with an average drying rate of 0.28 kg/h at maximum and minimum drying time of 10 h and 6 h respectively. The moisture loss by the groundnut in the dryer ranges from higher value to lower value of 1.05 kg to 0.55 kg for the red variety; 5.4 kg to 1.01 kg for the white variety; and 1.02 kg to 0.55 kg for the kampala variety respectively. Results further revealed that the drying air temperature has the greatest effect on the thermal efficiency, drying rate, drying time and moisture loss as compared with the drying air velocity. It was further discovered that the drying rates of the three varieties were relatively equal. However, the drying rates were in the order: white &gt; kampala &gt; red variety. It can be concluded that the hot-air dryer handled the drying of the three varieties of groundnut optimally with higher performances and in conformity to standard practices.

Design and Evaluate a Cabinet Dryer for Drying of Food and Agriculture Waste

Design and Evaluate a Cabinet Dryer for Drying of Food and Agriculture Waste

Impact of Substrate Disinfection on Yield and Efficiency of Drying Methods for Quality Preservation of Elm Oyster Mushroom Hypsizygus ulmarius (Agaricomycetes) and Its Medicinal Value.

This paper evaluated the effect of different substrate disinfection methods viz. hot water treatment, autoclaving and steam pasteurization at 100°C, 121°C, and 65°C, respectively, on yield of Hypsizygus ulmarius and effects of sun drying, oven drying and cabinet drying techniques at 25 ± 2°C, 40 ± 2°C, and 50 ± 2°C, respectively, on nutritional qualities of H. ulmarius. Hot water treated substrate gave higher yield (215.36 ± 1.49 g) and biological efficiency (71.78%) compared with autoclaved (194.45 ± 3.36 g and 64.81%) and steam pasteurized substrate (194.45 ± 3.36 g and 65.28%). The different drying methods used for drying the fruit bodies significantly influenced the nutrient profile of H. ulmarius. Highest moisture (6.95%), fiber (16.94%) and protein content (22.49%) was retained in sun dried fruit bodies whereas ash content (5.52%) was highest for oven dried fruit bodies. Cabinet dried fruit bodies showed significantly higher percentage of fats (1.82%) and carbohydrates (53.58%). In the DPPH assay the cabinet dried fruit bodies showed the highest antioxidant activity followed by sun dried and oven dried fruit bodies with respective IC50 values as 104.21 ± 0.14, 117.17 ± 0.07 and 163.57 ± 0.02. The drying methods proved to be effective in controlling the bacterial growth for a period of two months after which significant bacterial growth was noted.

Comparative assessment of indirect cabinet solar dryers in various operating modes versus direct cabinet dryers: A techno-economic analysis

A cost-effective indirect cabinet-type solar dryer was designed and developed to remove the moisture in green peas until their moisture content reaches 14–15 % with minimal energy supplied from external sources. The green peas were placed beneath the absorber plate of the modified solar cabinet dryer (MSCD) thereby preventing its exposure to direct sunlight. The performance of MSCD was assessed at three different air velocities and was compared with a conventional solar cabinet dryer (CSCD) operated in passive mode. Experimentation showed that when hot air from the upper chamber of MSCD was fed to its lower chamber at 0.0406 kg/s, the dried green peas were free from shrinkage, uneven drying, and browning. However, when hot air was fed to the lower chamber of MSCD at 0.00585 kg/s and 0.027 kg/s the dehydrated green peas underwent shrinkage. At the same time, the green peas dried in CSCD underwent shrinkage, uneven drying, and browning despite its higher efficiency (about 13.5 %) and shorter span (2 h and 30 min) taken for drying when compared to MSCD. Hence, CSCD and MSCD operated at an air velocity of 0.00585 kg/s, and 0.027 kg/s was found to be not suitable for dehydrating green peas. The efficiency of MSCD when hot air from the upper chamber was fed to its lower chamber at 0.0406 kg/s was 10.64 % and the payback period was 0.47 years.

Aplikasi enkapsulan hydroxy propyl methyl cellulose dan gum arab pada pembuatan bubuk semangka

Watermelon is a widely produced fruit in Indonesia. Abundant production and limited utilization make watermelons susceptible to quality loss and damage. Watermelon can be processed into powder to expand the variety of processing and reduce post-harvest losses. Various drying methods can be carried out, while a cabinet dryer at a temperature of 60-65 °C for 6 hours is considered the simplest method. Moreover, encapsulants such as hydroxy propyl methyl cellulose (HPMC) and gum arabic can be added. This study aims to apply different encapsulants in the watermelon powder manufacturing process and evaluate their effect on the physicochemical properties of the watermelon powder. A nested factorial randomized block design was used. The nest factor is the type of encapsulant, while the concentration is the nesting factor. The difference in concentration was 2.5 %, 5 % and 7.5 % for both HPMC and gum arabic. Each treatment was repeated four times. Watermelon powder quality parameters evaluated were moisture content, hygroscopicity, total phenol, antioxidant activity, color, and pH. ANOVA with = 5 % was implemented for statistical analysis and continued with Duncan's Multiple Range Test if a significant difference was observed. The increasing concentration of gum arabic increased the water content (2.19-3.42 %). While hygroscopicity decreased (21.84-17.33 %), total phenol decreased from 1370.91 to 765.23 mg GAE/kg sample. The antioxidant activity of the sample using the DPPH method was decreased (89.29-52.90 %). The use of gum arabic can maintain the red color of powder and the pH in the range of 5.39-5.57. On the other hand, HPMC application can reduce water content (3.32-2.15 %), hygroscopicity level 23.53-17.17 %; total phenol 1172.05-539.09 mg GAE/kg; antioxidant activity 65.88-29.54 %. The HPMC can maintain the red color of powder and increase the pH (5.83-6.30).