Dehydration Techniques Research Articles

Effective pervaporation dehydration of acrylic acid using alginate/BaTiO3 and alginate/TiO2 mixed matrix membranes

To develop an efficient pervaporation technique for acrylic acid dehydration, four types of BaTiO3 and TiO2 particles with various shapes and structures (commercial solid TiO2-S, synthesized sea urchin-like TiO2-U, commercial solid BaTiO3-S, and synthesized porous BaTiO3-P) were incorporated into sodium alginate (NaAlg) to fabricate mixed matrix membranes (MMMs) for comparison. 18 h crosslinking with CaCl2 was conducted to improve the acid-resistant property of Alg-based membrane. The filler particles and MMMs were systematically characterized via SEM, FTIR, BET, XRD, AFM, EDX, and TGA. The hydrophilicities of MMMs were enhanced with increasing filler contents, evidenced by the decreased water contact angles and raised water swelling degrees. When applied to pervaporate 5 wt% water/acrylic acid solution at 25 ℃, the MMMs significantly improved total permeation fluxes and separation factors compared to the pristine Alg membrane. When TiO2 particles were incorporated, the Alg/TiO2-U MMMs obtained lower separation factors than the Alg/TiO2-S MMMs due to the increased acrylic acid transport through big nanorod gaps and interfacial voids formed by the sea urchin-like TiO2-U shapes. On the other hand, the Alg/BaTiO3-P MMMs were superior to the Alg/BaTiO3-S MMMs in the dehydration performance, which was attributed to their porous structures. The optimal separation efficiency occurred at Alg/2 % BaTiO3-P MMM (water purity of 99.8 wt% and separation factor of 8700) with a stable performance over 168 h. When the optimal filler content was exceeded, the separation factor would decrease owing to the extra voids resulted from particle agglomeration. Moreover, the pervaporation performance could be enhanced with increasing feed temperature. In contrast, the separation selectivity was reduced, but the total permeation flux was improved, with increasing feed water concentration. It was further confirmed that the Alg/2 % BaTiO3-P MMM could successfully pervaporate a three-component mixture (10.3 wt% water/acetic acid/acrylic acid) at 65 ℃ to produce high-purity water (98.3 wt%). In conclusion, the design of Alg/BaTiO3 and Alg/TiO2 MMMs provides a potential approach for effective acrylic acid dehydration.

Assessing different tomato cultivars for dehydration suitability and selection of optimum dehydration technique

Assessing different tomato cultivars for dehydration suitability and selection of optimum dehydration technique

Impact of Dehydration Techniques on the Nutritional and Microbial Profiles of Dried Mushrooms.

The global consumption of dried mushrooms has increased worldwide because of their rich nutritional value and culinary versatility. Dehydration methods such as sun drying, hot air drying, freeze drying, and microwave drying are employed to prolong the shelf life of a food product. These methods can also affect the food product's nutritional value and the final product's microbial profile. Each technique affects the retention of essential nutrients like vitamins, minerals, and bioactive compounds differently. Additionally, these techniques vary in their effectiveness at reducing microbial load, impacting the dried mushrooms' safety and shelf life. This review addresses the gap in understanding how different dehydration methods influence dried mushrooms' nutritional quality and microbial safety, which is crucial for optimizing their processing and consumption. It targets researchers, food processors, and consumers seeking to improve the quality and safety of dried mushrooms. This review comprehensively examines the impact of major dehydration techniques, including sun drying, hot air drying, microwave drying, and freeze drying, on the nutritional and microbial profiles of dried mushrooms. Each method is evaluated for its effectiveness in preserving essential nutrients and reducing microbial load. Current research indicates that freeze drying is particularly effective in preserving nutritional quality, while hot air and microwave drying significantly reduce microbial load. However, more well-designed studies are needed to fully understand the implications of these methods for safety and nutritional benefits. These findings are valuable for optimizing dehydration methods for high-quality dried mushrooms that are suited for culinary and medicinal use.

Inactivation kinetics of Bacillus cereus and Aspergillus niger spores in dehydrated onion shreds after pulsed light and infrared treatments

Fresh onions are dehydrated to increase their shelf-life. Primarily, open dehydration techniques like solar dehydration come with the problem of contamination through natural air convection. A solar conduction dryer that uses conduction, convection, and radiation for dehydration of food samples is exploited in this study. The food samples are often contaminated by Bacillus and Aspergillus species spores. As a remedy, pulsed light treatment as a non-thermal technology and infrared treatment as a thermal technology are studied and compared. Bacillus cereus and Aspergillus niger spores are chosen as a representative of bacterial and fungal contamination in onions. Dehydrated onion shreds with varying water activities (0.4, 0.5, 0.6) were treated. The spore inactivation was best described by Weibull model as compared with first-order model. Scanning electron microscopy images of the microbial cells showed surface distortions on the bacterial and fungal spores. The effect of the treatment technologies on the colour, flavour (thiosulphinate and pyruvic acid concentration), total phenolic and flavonoid content, and ascorbic acid concentration are compared. Overall, pulsed light treatment showed promising inactivation with a maximum log reduction of 4.5 log B. cereus spores·g−1 and 3.1 log A. niger spores·g−1 at 2.131 J·cm−2 in samples with water activity 0.6. The inactivation rate increased with an increase in water activity. The colour was better retained in pulsed light treated samples. The thiosulphinate content (9.24 μmol·g−1), total phenolics (0.268 mg GAE·g−1), and flavonoid content (0.344 mg QE·g−1) in the sample were improved upon pulsed light exposure.Graphical

Innovative microencapsulation of hemp seed oil using plant-based biopolymers: A comparative analysis of dehydration techniques on core stability, digestibility and release pattern

This study explores various dehydration methods, including freeze drying (FD), spray drying (SD), and the supercritical carbon dioxide solution-enhanced dispersion (SEDS) process, to encapsulate hemp seed oil (HSO) within a complex matrix of hemp seed protein isolate and alginate. One noteworthy aspect of this study involves the in-depth analysis of the structural characteristics of the delivery systems, highlighting their pivotal role in shaping HSO release patterns. The findings indicate that SEDS microcapsules (SEDS-M), with their smallest particle size and smooth, spherical morphology, effectively preserved structural integrity and provided controlled oil release across diverse pH levels (3–9) and salt concentrations (0–200 mM). During the gastrointestinal phases, minimal oil release occurred during oral digestion (<25%) for all samples, while the significant gastric release occurred in FD (39.8%) and SD microcapsules (33.4%). With their highest storage stability, SEDS-M demonstrated superior delayed and sustained release (27.9%) during gastric transit, making them ideal for protecting sensitive ingredients and ensuring targeted intestinal delivery.

Advancements in Coffee Manufacturing: From Dehydration Techniques to Quality Control

Advancements in Coffee Manufacturing: From Dehydration Techniques to Quality Control

Comparative study on dehydration of isopropanol and acetonitrile by pervaporation using PEBA/PANI/zeolite mixed matrix membranes

ABSTRACT Isopropanol (IPA) and Acetonitrile (ACN) solvents form azeotrope with water and separation by conventional processes is energy intensive. So, Pervaporation (PV) process became quite prominent and an alternative technique for dehydration of azeotropic mixtures. The selection of membrane places a crucial role in pervaporative separation and Mixed Matrix Membranes (MMMs) were widely employed. In this context, MMMs designated as PEBA-PANI and PEBA-PANI-4A were prepared by embedding PANI, zeolite 4A fillers in PEBA matrix. The synthesised zeolite particles, pristine PEBA and MMMs were characterised by XRD, FTIR, as well as contact angle measurements. Further, surface morphology and average particle size of zeolite particles are observed using SEM. Sorption studies with varying composition of isopropanol, and acetonitrile aqueous mixtures were correlated with their PV performances. The PEBA-PANI-4A MMMs showed higher % sorption of 11.34 and 8.57 for IPA–Water and ACN–Water systems respectively. Similarly greater pervaporation flux and selectivity of 0.28 kg/m2h and 720 were obtained for IPA–Water and 0.068 kg/m2h and 564 for ACN–Water systems at 10 wt. % water concentration. The PV results revealed that the MMMs exhibited better performance than pristine PEBA. All three membranes showed greater sorption, flux and selectivity for IPA-Water system than ACN-Water system.

Advanced Dehydration Techniques Standardized for Flowers of Gomphrena globosa L.

The present experiment was conducted on standardizing dehydration technique for Gomphrena globose flower by using embedding drying methods in room temperature and hot air oven at 55°C was done. The experiment consisted of 10 treatments with 3 replications designed in completely randomized design. Treatments used were as; T1-Boric acid (room temperature), T2-Silica gel (room temperature), T3-Sand (room temperature), T4-Sawdust (room temperature), T5-Cocopeat (room temperature), T6-Boric acid (hot air oven at 55 °C), T7-Silica gel (hot air oven at 55 °C), T8-Sand (hot air oven at 55 °C), T9-Sawdust (hot air oven at 55 °C), T10-Cocopeat (hot air oven at 55 °C). The most reduction in flower fresh and dry weight, measuring 2.36 and 2.12 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The least reduction in flower fresh and dry diameter, measuring 1.92 and 1.81 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The highest drying duration for gomphrena in T3 (Sand) and T4 (Sawdust) treatments was 234.21 and 210.40 hrs at room temperature. The boric acid and silica gel demonstrated outstanding performance in terms of quality parameters, including texture, color, and overall appearance. Among all treatment, embedding drying with silica with hot air oven dehydration at 55°C was found to be best in term of reduction in weight, diameter and overall colour, appearance and texture of Gomphrena globose flowers.

Dehydration Impact on Antioxidant Potential and Phenolic content of Backhousia citrodora leaves

The most popular method for food preservation is dehydration. In order to enhance the overall quality and prolong the longevity of herbal products, it is imperative to carefully choose optimal dehydration conditions. The dehydration of Backhousia citriodora, also known as lemon myrtle leaves (LML), was conducted via three distinct techniques: conventional dehydration at temperatures of 40, 50, and 60°C (referred to as CD40, CD50, and CD60, respectively); vacuum dehydration at the same temperature as conventional dehydration with a pressure of 50 mbar; and heat pump dehydration at a constant temperature of 45°C. The antioxidant capacities, specifically the radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP), along with the total phenolic content (TPC), were evaluated. HPD samples came up second to VD samples in terms of TPC retention, DPPH activity, and FRAP test, whereas CD samples had the lowest biochemical content across all dehydration conditions. The TPC and antioxidant activity in the CD sample exhibited a substantial reduction as the dehydration temperature increased. After dehydration, the CD60 sample had the largest reduction in TPC, DPPH, and FRAP values. Maximising the retention of biochemical content is of utmost importance in post-harvest processing as it serves as an indicator of greater retention. Therefore, the selection of appropriate dehydration techniques and conditions is critical in achieving this objective.

Effects of Cold Plasma Pretreatment and Cultivar on the Drying Characteristics, Biochemical, and Bioactive Compounds of 'Tropica' and 'Keitt'Mangoes

PurposeMango is a well-known and widely consumed fruit for its savoury taste and nutritional benefits. However, a lack of efficient postharvest handling prior to its storage could gradually lead to undesirable changes that cause postharvest losses. Dehydration techniques such as hot air drying have shown to minimize the water activity thereby preserving fruit shelf-life. Pretreatment prior drying has the advantage of shortening the drying times, consuming less energy, substituting chemical use, and maintaining the quality attributes of agricultural products. Therefore, the main purpose of this research is to assess the application of cold plasma (CP) as a pretreatment step before drying ‘Tropica’ and ‘Keitt’ mango slices.MethodsThe effect of low-pressure cold plasma pretreatment duration (5 and 10 min) and mango cultivar differences was investigated on drying properties, quality attributes, and microbial load. Thin layer mathematical models fitted were fitted to the data collected to describe the drying behaviour.ResultsMango cultivars behaved differently during drying as ‘Keitt’ samples had a shorter drying time (10 h) compared to ‘Tropica’ samples (12 h). Logarithmic model best predicted the drying behaviour with a determination coefficient R2 of 0.99 and RMSE of 0.0664. Change in bioactive compounds, antioxidant capacity, and microbial load of ‘Tropica’ and ‘Keitt’ mango slices were significantly affected by CP pretreatment and drying (p < 0.05).ConclusionThe findings of this study showed that cold plasma improved the drying rate of dried mango slices. Total phenolic and antioxidant activity were improved with cold plasma treatment of 10 min. In summary, cold plasma improves drying kinetics and the quality attributes of mango fruit.

Simulation of ice deposition in a freeze dryer condenser: A computational fluid dynamics study

The development and validation of a mechanistic model for the deposition of ice within a freeze-dryer condenser using Computational Fluid Dynamics is presented in this paper. Freeze-drying, a dehydration technique used widely in the pharmaceutical and food industries, involves the sublimation of frozen product moisture under controlled conditions. The efficiency of the condenser has a significant impact on the overall process efficiency and product quality. Therefore, a comprehensive understanding of ice deposition is essential for freeze-drying processes. The proposed condensation model integrates fundamental heat and mass transfer principles with the specific interactions that occur at the solid-vapour interface during ice deposition, and integrates it further with transport phenomena in the condenser, including fluid flow, heat and vapour transport influencing the deposition kinetics of the ice. To validate the model, experiments were conducted under controlled freeze-drying conditions, and the results compared with the results of the developed model. The numerical results fell within the confidence interval of the measured values, which shows a high degree of agreement between the model predictions and the experimental data, and confirms the reliability of the proposed approach. Using the validated model, a parametric study was also conducted, to evaluate the effects of condenser temperature, sublimation rate and the presence of inert gas on the pressures within the system and the efficiency of the deposition. The mechanistic model provides detailed insights into the ice deposition kinetics during freeze drying, and enables process engineers to optimise the condenser design and operating parameters in order to improve performance and product quality.

Allulose‐crystallized fruits: Effect of non‐thermal air‐drying and UV‐A light dehydration of osmotic solutions

AbstractThe purpose of this research was to confirm the suitability of allulose to produce crystallized fruits under nonthermal conditions and the suitability of UV‐A light dehydration to concentrate the osmotic solutions. Mangoes and apples were subjected to osmotic drying with either sucrose or allulose, which was followed by an air‐drying step at room temperature to further concentrate the crystallized fruits. There was no significant difference in the dehydration kinetics parameters between the two sugars in each crystallized fruit. Color evaluations showed that allulose was able to better preserve the color of the original raw fruits in the final crystallized samples. Electron microscopy images suggested a more uniform diffusion of allulose as compared to sucrose for both fruits. Similarly, liquid chromatography and infrared spectroscopy analyses confirmed the successful absorption of both sugars into both fruits, with allulose having a final higher concentration in both mango and apple (51.7 ± 5.6% and 70.8 ± 7.7% w/w, respectively) as compared to sucrose (48.6 ± 2.9% and 58.3 ± 3.4% w/w, respectively). UV‐A light dehydration showed to be able to increase the recovery of the sugars from osmotic solutions better than in conditions without UV‐A light exposure. When only air flow was used, it was possible to remove 85.3 ± 4.6% and 78.6 ± 0.6% of the original moisture in the sucrose and allulose solutions, respectively. In contrast, under UV‐A light dehydration, the percentage of the original water removed from the sucrose and allulose solutions was 95.2 ± 1.8% and 83.1 ± 1.9%, respectively.Practical applicationsThere is an increasing trend toward producing foods that are healthier for the general population. The use of rare sugars like allulose offers a promising alternative to accomplishing this. In addition, it has become imperative to develop processes that are more sustainable. The use of air‐drying at room temperature can represent an effective approach to develop more sustainable food manufacturing processes. More specifically, the use of UV‐A light dehydration (which is a non‐thermal food dehydration technique) for the recovery of solutes or the concentration of osmotic solutions can also represent an effective aid in this type of processes.

Potential of vacuum impregnation and osmotic dehydration techniques in producing jaggery-fortified apple snacks

Jaggery is proposed as a non-conventional osmotic agent to produce nutritious sustainable apple snacks via vacuum impregnation and osmotic dehydration, followed by air drying or freeze drying.

IoT implemented Osmotic Dehydrator

Osmotic dehydration is a dehydration technique that allows the preservation of the organoleptic characteristics of the food and its nutritional properties compared to other preservation methods, such as hot air drying or solar drying. Studies on this dehydration process are usually carried out on a laboratory scale and with the constant presence of the evaluator, interrupting the process for sampling. That is why the main objective of this research was to build an automated osmotic dehydration equipment implementing the Internet of Things (IoT). The measurable factors involved in the process were determined, and the necessary sensors and actuators were chosen along with the best IoT alternative for the process. A prototype was built, which allows for controlling the agitation of the osmotic solution, temperature control, and remote monitoring of concentration and temperature variables. The equipment was tested by evaluating its performance in the dehydration of melon and apple, where the ANOVA tests demonstrated the significance (p &lt; 0.05) of the factors chosen as part of the equipment design and their interaction with the process. In the apple samples, a weight loss of up to 44.007% and a water loss of 53.234% were obtained. For melon, the process showed greater efficiency in dehydration, with values of 75.259% for weight loss and 75.979% for water loss.

Optimization and modeling of vacuum impregnation of pineapple rings and comparison with osmotic dehydration.

The vacuum impregnation (VI) process parameters (vacuum pressure=20-60kPa; VI temperature=35-55°C; concentration of the sucrose solution=40-60°Brix; and vacuum process time=8-24min) for pineapple rings were optimized based on the moisture content (MC), water loss (WL), solids gain (SG), yellowness index (YI), and total soluble solids (TSS) content of pineapple rings using response surface methodology (RSM). A relationship was developed between the process and response variables using RSM and artificial neural network (ANN) techniques. The effectiveness of VI was evaluated by comparing it with the osmotic dehydration (OD) technique. The optimum condition was found to be 31.782kPa vacuum pressure, 50.441°C solution temperature, and 60°Brix sucrose concentration for 20.068min to attain maximum TSS, YI, SG, and WL, and minimum MC of pineapple rings. The R2 values of RSM models for all variables varied between 0.70 and 0.91, whereas mean square error values varied between 0.76 and 71.58 and for ANN models varied between 0.87-0.93 and 0.53-193.78, respectively. Scanning electron micrographs (SEM) revealed that parenchymal cell rupture was less in VI than in OD. The VI pineapple rings exhibited more pores and high SG, as compared to OD, due to the pressure impregnation. Spectroscopic analysis affirmed that the stretching vibrations of intermolecular and intramolecular interactions were significant in VI as against OD. The VI reduced the drying time by 35% compared to OD, with the highest overall acceptability score and lower microbial load during storage. PRACTICAL APPLICATION: Pineapple is a perishable fruit, which necessitates processing for extended shelf life. This study highlights the potential of the vacuum impregnation process as a promising alternative to conventional preservation methods such as osmotic dehydration for pineapples.

Toward a10 dB net-gain waveguide amplifier in an Er3+-Yb3+ co-doped phosphate glass.

High-gain materials and high-quality structures are the two main conditions that determine the amplification performance of optical waveguides. However, it has been hard to balance each other, to date. In this work, we demonstrate breakthroughs in both glass optical gain and optical waveguide structures. We propose a secondary melting dehydration technique that prepares high-quality Er3+-Yb3+ co-doped phosphate glass with low absorption loss. Additionally, we propose a femtosecond laser direct-writing technique that allows controlling the cross section, size, and mode field of waveguides written in glass with high accuracy, leveraging submicron-resolution multi-scan direct-writing optical waveguide technology, which is beneficial for reducing insertion loss. As a proof of concept demonstration, we designed and fabricated two kinds of waveguides, namely, LP01- and LP11-mode waveguides in the Er3+-Yb3+ co-doped phosphate glass, enabling insertion loss as low as 0.9 dB for a waveguide length of 2 mm. Remarkably, we successfully achieved an optical amplification for both the waveguides with a net gain of >7 dB and a net-gain coefficient of >3.5 dB/mm, which is approximately one order of magnitude larger than that in the Er3+-Yb3+ co-doped phosphate glass fabricated by the traditional melt-quenching method. This will open new avenues toward the development of integrated photonic chips.

Role of Drying Technologies on the Drying Kinetics, Physical Quality, Aroma, and Enzymatic Activity of Pineapple Slices

With a loss of about 50% of fruits and vegetables annually, there is a continuous need to improve food handling from the farm to the consumer. The solution may come partially from the selection of proper processing techniques that produce healthy and high-quality sustainable food, preserve natural resources, and contribute to prospering local economies. Pineapple is one of the most consumed fruits worldwide due to its remarkable sensorial and health-promoting attributes. Nevertheless, pineapple’s high moisture content (81–86%) impedes its long-term preservation, resulting in product losses and economic, social, and environmental challenges. Drying is the oldest processing technique for most fruits and vegetables. However, the investigation of modern technologies, such as infrared drying of pineapple, is limited. Moreover, industries are investigating different methods to dry faster, thereby saving energy and reducing environmental impact. Hence, this study used four drying methods to dry pineapple slices to allow the estimation of the most promising technique: infrared drying (ID), freeze-drying (FD), convective drying (CD), and relative humidity convective drying (RHCD). The impact of these dehydration techniques on drying kinetics, physical attributes (color, texture, rehydration, microstructure), aroma, and enzymatic activity (polyphenol oxidase, peroxidase) were reported. The results showed that ID had the highest coefficient of effective moisture diffusivity and drying rates and the shortest drying period (33.45%, 36.18%, and 76.12% lower than CD, RHCD, and FD, respectively). Drying curves were successfully fitted with the parabolic and logarithmic models, which showed higher coefficients of determination and lower reduced chi-square and root mean square error than the Newton and inverse logarithmic models. FD and ID triggered minor browning indexes, leading to the brightest products. RHCD and ID slices had the highest textural values and aroma concentrations, while FD samples showed the lowest. However, FD samples had a higher rehydration ratio than other dried products and showed slight structural modifications. Regarding polyphenol oxidase and peroxidase inactivation, ID was superior, followed by CD, RHCD, and FD. The actual results suggest that infrared drying could be an efficient technique for the obtention of high-quality dehydrated pineapple fruits in a short time.

Study of relations between chemical, colour and fluorescence properties of raw and dried meat powders of cow and yak (Bos grunniens)

Gluteus medius, Longissimus thoracis, and Semitendinosus muscles from the cow and yak (Bos grunniens) reared in the Kyrgyz Republic were dried by convective (hot air) drying and freeze drying. The dried muscles were grinded into fine powders and along with raw muscles were evaluated for water activity (aW), chemical composition (moisture, fat, protein), colour characteristics (L, a, and b values), fluorescence of intrinsic fluorophores (tryptophan, vitamin A, and riboflavin). Processing of measured data tables using common components and specific weights analysis (CCSWA) showed close relations among the chemical, colour, and fluorescence data. CCSWA discriminated muscles depending on chemical composition, animal type, and drying technique applied based on the chemical properties, colour characteristics, and fluorescence spectra. The freeze drying was approved as a preferable dehydration technique comparing with convective drying as the one causing less discoloration to meat. Partial Least Squares Regression (PLSR) models developed using fluorescence spectra allowed accurate quantitative predicting of water activity (aW), moisture, fat, and protein contents, and colour characteristics (L, a, and b values).

Effects of Tray and Freeze Drying on Physico-chemical and Structural Properties of Fig Fruit Powder

A study was conducted on the drying of fig fruits using tray-drying [50 °C, 60 °C, 70 °C for 3 h] and freeze-drying [(-)43 °C for 24 h] dehydration techniques. The physico-chemical properties of fig fruit powder were studied. Different temperatures and methods of drying had effects on the moisture content, water activity, physico-chemical properties, and structural properties. Moisture content and water activity were in the range of 6.5-8.5% (w.b.) and 0.40-0.60, respectively. Powders of 15- 30 μm size range and with a flaky texture had moderate flowability. FTIR analysis exhibited peaks of varied range. XRD analysis showed that the powders were predominately amorphous in nature, and C-type starch was present.

Convective drying of pumpkin: Brief literature review and new data for organically produced indigenous pumpkin (Cucurbita pepo L.) over an expanded temperature range

Selected cultivars form part of the neglected and underutilized species (NUS), which can contribute to building sustainable and resilient food systems, particularly for food-insecure households. Advances in the drying of pumpkin cultivars are briefly reviewed. Background on drying, including pretreatment techniques, is discussed. It emerged that convective air drying remains the most used dehydration technique, while most pretreatment and drying approaches, although innovative and promising, have not yet been investigated for pumpkin species. Areas for future scientific investigations are also suggested. A closer look at the literature data revealed notable inconsistencies for pumpkin diffusivity data even for the same species. For this reason, independently of the review, new data are reported in this study for the Cucurbita Pepo cultivar in a quest for more accuracy and a wider temperature validity range. A convective dryer using hot air was used to determine the drying characteristics of pumpkin (Cucurbita pepo L.) slices at four different temperatures (40, 45, 50, 55 and 65) °C at a constant velocity of 1.5 m/s. The extended temperature range and the large number of experimental temperatures were meant to increase the newly reported properties’ accuracy and validity range. The Page model stood out as the most accurate approach to describe the investigated dehydration process. Pumpkin effective diffusivity was calculated as 3.74–7.30 × 10−9 m2/s while the activation energy was 21.07 kJ/mol based on experiments undertaken in the present study. The newly obtained data did not solve the problem associated with inconsistencies between the two data sets found in the literature for drying the same pumpkin cultivar. The reported data would be helpful in the accurate determination of diffusivity data instrumental for convective drying process modelling and optimization.