Pa ge 1 Pa ge 76 American Journal of Food Science and Technology (AJFST) Effect of Pre-treatments on the Osmotic Dehydration and Mass Transfer Behaviour of Sweet Potatoes (Ipomoea batatas LamIpomoea batatas Lam.) MFH Shikder1, Md Nahid Hossain Jany1*, Juwel Rana2, M. Burhan Uddin1 Volume 4 Issue 1, Year 2025 ISSN: 2834-0086 (Online) DOI: https://doi.org/10.54536/ajfst.v4i1.4479 https://journals.e-palli.com/home/index.php/ajfst Article Information ABSTRACT Received: February 05,, 2025 Accepted: March 03, 2025 Published: May 08, 2025 Food security is increasingly threatened by rapid population growth, climate change, and resource constraints, necessitating efficient preservation techniques to minimize post-harvest losses. This study investigates the osmotic dehydration process of two sweet potato (Ipomoea batatas Lam.) varieties, Local Sada and Kamala Sundari, under varying sugar concentrations (40%, 50%, 60%), temperatures (30°C, 40°C, 50°C, and 60°C), slice thickness (3 mm or 5 mm), and pre-treatment conditions (blanched or unblanched). The research problem addresses the high perishability of sweet potatoes post-harvest, leading to significant food losses, and the lack of optimized osmotic dehydration parameters tailored to specific sweet potato varieties. The novelty of this study lies in its comprehensive examination of multiple processing parameters simultaneously within a single experimental framework, allowing for an in-depth understanding of mass transfer mechanisms and varietal differences. Results indicate that increased sugar concentrations and temperatures enhance dehydration rates, with blanching further accelerating mass transfer by increasing cell permeability. However, varietal differences were significant: Kamala Sundari exhibited slower yet more controlled dehydration, maintaining better structural integrity, while Local Sada dehydrated faster but showed higher susceptibility to structural collapse. Slice thickness also played a crucial role, as thinner slices (3 mm) dehydrated more quickly but were prone to texture loss compared to thicker slices (5 mm). Unblanched samples, despite slower dehydration rates, retained better textural attributes. These findings have strong industrial relevance, providing a framework for optimizing osmotic dehydration conditions tailored to different sweet potato varieties, ensuring improved product quality and reduced post-harvest losses in food processing industries. Keywords Food Preservation, Mass Transfer, Osmotic Dehydration, Pretreatment, Structural Integrity, Sweet Potato 1 Department of Food Technology & Rural Industries, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh 2 Department of Nutrition & Food Engineering (NFE), Daffodil International University (DIU), Bangladesh * Corresponding author’s e-mail: nahidhj.research@gmail.com INTRODUCTION Food security worldwide is increasingly threatened by rapid population growth, climate change and an overburdened set of resources (Sarker et al., 2023). Protecting nutrient-rich crops through processing is vital. Sweet potatoes (Ipomoea batatas L) have become an important crop in developing nations due to their high calorific yield, nutritional profile, and ability to adapt to marginal growing conditions (Otálora et al., 2024). Food production is vital in providing essential nutrients and increasing food security, and it is critical to economic and public health stability (Peng & Berry, 2018). Tropical and sub-tropical regions rely heavily on tuber crops such as sweet potatoes for caloric intake (Rinaldo, 2020). However, the high amount of moisture makes it highly perishable following harvest and usually results in food loss (Nath & Sil, 2008). Osmotic dehydration is a widely used method in the food industry to preserve fruit and vegetables by reducing the amount of water they contain while conserving their nutritional and sensory quality. To do this, food items are submerged into an osmotic solution composed of salt or sugar, which creates an osmotic pressure gradient to remove water from food structures while permitting solvent diffusion (Silva et al., 2014; Cheng et al., 2023; Osae et al., 2024). Sweet potatoes (Ipomoea batatas L.) are particularly well known for their rich nutrient content; therefore, sweet potato dehydration produces intermediate moisture products, which improve shelf life and flavor profiles (Malakar et al., 2021). Dehydration by osmotic is highly dependent on various variables, including the amount of osmotic solution applied, processing temperature, sample thickness, pretreatment methods (blanching) used as well as sweet potato variety differences that influence cell structure, moisture content and chemical composition that ultimately impact dehydration rates as well as final product characteristics (de Souza Silva et al., 2011). Osmotic dehydration depends on many variables, including the quantity and temperature of osmotic solutions used, sample thickness, method of pretreatment (blanching) utilized and sweet potato varieties whose cells alter cell structures, moisture content and chemical composition to influence rate of dehydration as well as final characteristics (Lagnika et al., 2021). Sweet potatoes degrade rapidly due to their high moisture levels, leading to significant post- harvest losses (Sarker et al., 2023; Araújo & Pena, 2023). However, the effect of key processing parameters such as sugar concentration, temperature, slice thickness, and pretreatment (blanching, etc.) on sweet potato degradation remains uncertain (Kadir et al., 2024; Dermesonlouoglou et al., 2025). Unblended on the kinetics of osmotic dehydration has not been sufficiently researched, nor Pa ge 77 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 has the significance of varietal differences such as Sada vs Kamala Sundari in dehydration behavior been recognized fully. This study addresses these gaps by investigating how processing variables affect water loss and solids gains during osmotic dehydration, in combination with varietal characteristics to optimize dehydration processes for product quality and effectiveness. This study aims to investigate the effects of sugar concentration in the solution (40%, 50% and 60%) as well as the temperature, the thickness of slices (3 and 3 millimeters), and the pre-treatment method (blanched or. non-blanched) on the dehydration behavior of two varieties of sweet potato such as Local Sada as well as Kamala Sundari. The research focuses on studying the mechanisms of water loss and gain of solids during the process of osmotic dehydration in order to improve processes to ensure efficient removal of moisture while preserving the desirable structural and sensory characteristics (Lagnika et al., 2021; Pandiselvam et al., 2022). The uniqueness of this research is the holistic method of analysis. In contrast to previous studies that looked at individual parameters on their own the research we are conducting simultaneously examines various critical variables, including slice geometry, pretreatment and differences between varietals within a single experimental framework (Antonio et al., 2008; Corrêa et al., 2017; Wu et al., 2020; Wang et al., 2025). This integrated analysis will provide extensive insight into the mechanisms of mass transfer in osmotic dehydration. The report will also offer practical recommendations for the development of specialized methods to preserve sweet potatoes. The findings will aid in the reduction of postharvest losses as well as increasing the shelf-life of this vital crop, with a substantial impact on industry and food security. MATERIALS AND METHODS Raw Materials and Identification Two kinds of sweet potatoes, Local Sada and Kamala Sundari, were purchased from a local market in Mymensingh, Bangladesh. A plant pathologist at Bangladesh Agricultural University verified the variety’s identity using morphological traits. Only fresh tubers with no defects were used in the tests. Preparation of Raw Materials Tubers were cleaned under running tap water to eliminate soil, cleansed with a food-grade product, rinsed with distilled water, and dried by air. They were then peeled with a stainless-steel peeler to reduce the loss of flesh and cut into 5 and 3 mm pieces using an automated slicer to ensure uniformity across the samples (Kwaw et al., 2023; Šovljanski et al., 2024). Pre-Treatment (Blanching vs. Unblanching) Slices were split in two parts. To blanch slices, they were soaked in water at a temperature of 90°C for 3 minutes before being chilled in ice water for 2 minutes in order to stop the cooking. The samples that were not blanched were processed with no heating treatment (Osae et al., 2024). Osmotic Dehydration Process Analytical-grade sucrose solutions were made at 40, 40%, 50%, and 60% (w/v) after dissolving the necessary amount of sucrose in the distilled water. Slices of sweet potato (both blanched and unblanched with a thickness of 3 mm and 5 mm) were immersed in a solution of sugar at a fruit-to-solution ratio of 1:10. Dehydration was conducted in a temperature-controlled water bath at 30°C, 40°C, 50°C, or 60°C for 6 hours, with a peristaltic pump circulating the solution at 500 ml/min (tube bore size: 8.0 mm). The samples were taken at predetermined intervals (30, 60, 120, 180, 240, 300, and 360 minutes) to determine the amount of mass transferred (Antonio et al., 2008; Pang et al., 2021; Rastogi, 2023). Total Solids Determination The quantity of total solids in those sweet potato pieces was measured using gravimetric analysis by drying in a vacuum oven at 70°C for 24 hours according to the procedure explained in the work of AOAC (Association of the Official Analytical Chemistry). Sweet potato slices were then transferred to aluminum dishes pre-weighed to ensure that all dishes’ weights were precisely recorded (Tayyab Rashid et al., 2020; Osae et al., 2024; Rindang et al., 2024). The dishes and the slices were then put in a vacuum oven set at 70°C for a drying time lasting 24 hours (Balladin & Headley, 1999). After drying, the samples were allowed to cool down to room temperature with a desiccator to avoid moisture absorption from the surroundings. The aluminum dishes that held dried samples were weighed to determine the weight (Pang et al., 2021). The content of total solids (TS) was calculated by using the following equation (Equation 1): Total Solid (TS),% =(W3-W1)/(W2-W1) (1) Where, W1 = Weight of aluminum dish, W2 = Weight of dish and sample, W3 = Weight of dish and the vacuum dried samples Determination of Mass Transfer The mass transfer during the osmotic dehydration process of sweet potato slices was assessed by measuring two key parameters: Water Loss (WL) and Solid Gain (SG). Water Loss (WL) To determine the loss of water during dehydration osmotically of slices of sweet potatoes, we estimated their decrease in weight after dehydration by capturing their mass at the beginning (Mi) prior to observing how dehydrated each slice was at various intervals of sampling (30, 60, 120, 180, 240, and 360 mins) by using Genina- Soto et al.’s (2001) equation that is described below (Equation 2): Water loss (WL),% =(Mi-Mo)/Mi (2) Where, Mi is the initial mass of the sweet potato slice, and Mo is the mass of the osmotically dehydrated slice at a specific time interval. Pa ge 78 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 Solid Gain (SG) Solid gain was assessed by measuring the growth in the solids content of the sweet potato slices because of the absorption of sugar in the Osmotic solution. The total solids of both the original slices (TSi) and the dehydrated osmotically soaked cut (TSo) were determined by gravimetric analysis by using a vacuum oven to dry at 70°C for a period of 24 hours (Pang et al., 2021). The gain in solids was calculated by using the following equation (Equation 3): Solid Gain (SG),% =(TSo-TSi)/Mi (3) Where, TSo = Total solids of the sample after osmotic dehydration, TSi = Initial total solids of the sample before dehydration, and Mi = Initial mass of the sweet potato sample. This part should contain adequate detail to reproduce reported data. It can be divided into subsections to demonstrate data type and collection, and also if several methods are described. Methods already published should be indicated by a reference; only relevant modifications should be described. The methodology should be written concisely in detail by maintaining the continuity of the texts. RESULTS AND DISCUSSION This research set out to assess the effects of sugar solution concentration on the dehydration of osmotic fluids by analyzing various parameters, including concentration (40%, 50% or 60%), temperature (30°C, 40°C, 50°C, 60°C), sample preparation method (blanched versus non-blanched), and sample size (3mm thick samples for uniformity during the experiment). Key findings and conclusions can all be drawn based on the experiment’s results. Osmotic Dehydration Behavior Effect of Pretreatment on the Dehydration Behavior of 3mm Thick Sweet Potato (var. Local Sada) Results indicate that increasing sugar solution concentration between 40% and 60% increases the efficiency of osmotic dehydration significantly due to an increase in pressure gradient caused by an increase in concentration (Antonio et al., 2008). Dehydration rates at 40% concentration were lower than at 50% and 60% concentration, suggesting a minimum concentration is necessary for effective moisture removal (these results align with established principles of osmosis (Table 1); an increase in concentration accelerates water molecules through a semipermeable membrane that surrounds food ingredients) (Jain & Chauhan, 2022). Temperature was an integral component of osmotic hydration (Wang et al., 2025). Rising from 30°C to 60°C would decrease viscosity in this sugar mixture and thus accelerate mass transfer (Lagnika et al., 2021). Additionally, rising temperatures boost energy kinetics for water molecules, allowing easier escape from samples. However, extreme temperatures such as 60°C may cause changes to color, texture, nutritional quality, and other aspects. These extreme changes were especially prevalent with blanched samples due to increased thermal changes (Wang et al., 2025). Blanching, which involves brief exposure to hot water or steam, enhances permeability within a sample’s cell structure, facilitating faster water removal during osmotic dehydration. This was particularly evident at higher sugar concentrations (50% and 60%) and temperatures between 50°C and 60°C. Unblanched samples exhibited slower dehydration rates due to their intact cell walls, which presented resistance against diffusion; blanching improved dehydration efficiency but may have led to some loss of soluble solids, as seen previously. Interactions among sugar concentration, temperature, and sample type (blanched vs. unblanched) revealed complex dynamics (Osae et al., 2024). For instance, while a 60% sugar solution mixed with 60°C resulted in the highest dehydration rates, it might not be optimal in terms of sensory or nutritional attributes of samples; thus, a balance must be found between dehydration efficiency and product quality preservation. Furthermore, blanched samples benefitted more from increased temperatures than unblanched ones, emphasizing the necessity of tailoring processing conditions according to specific characteristics of the raw material used (Wu et al., 2020; Pang et al., 2021). Table 1: Water loss over time at various temperatures and sugar solution concentrations for 3mm thick sweet potato slices (var. local sada) Pa ge 79 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 Effect of Pretreatment on the Dehydration Behavior of 3mm Thick Sweet Potato (var. Kamala Sundari) This research studies the dehydration characteristics of sweet potato slices from two varieties, Local Sada and Kamala Sundari, under varying conditions of sugar solution concentration (40%, 50%, and 60%), temperature, and pretreatment methods (blanched or unblanched). Local Sada was tested with 3mm and 5mm slices, while Kamala Sundari only required 3mm slices for experiments (Table 2). Our findings indicate that higher sugar concentrations and elevated temperatures significantly accelerate both varieties’ water loss and solid gain. However, varietal differences were evident; Kamala Sundari showed slower dehydration rates but superior structural integrity than Local Sada. Blanching enhanced dehydration efficiency in both cases, leading to greater softening with local Sada. Table 2: Water loss over time at various temperatures and sugar solution concentrations for 3mm thick sweet potato slices (var. kamala sundari) Pa ge 80 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 A comparison between these varieties underscores the role that thickness and cellular structure have on dehydration kinetics. Thinner slices (3 mm) dehydrated faster for local Sada than thicker (5 mm), emphasizing geometry’s role in mass transfer. On the contrary, Kamala Sundari displayed more controlled dehydration conditions that preserved quality attributes more effectively than Local Sada; these insights highlight the necessity of customizing dehydration parameters to specific sweet potato varieties to optimize both efficiency and product quality; such tailored approaches can help achieve desired outcomes while mitigating adverse side effects like excessive shrinkage or nutrient loss (Rastogi, 2023). Effect of Sugar Solution Concentration, Temperature, Blanching on Dehydration Behavior of 5mm Thick Sweet Potato (var. Local Sada) Results indicate that increasing sugar solution concentration dramatically accelerates osmotic dehydration. At 40% sugar concentration, dehydration rates were relatively lower than 50% and 60% sugar concentrations (Table 3). This can be explained by the higher osmotic pressure gradient created by more concentrated solutions, which drives water out more effectively (de Souza Silva et al., 2011; Silva et al., 2014). At every temperature condition, 60% sugar solutions demonstrated superior dehydration efficiency. These findings confirm the principles of osmosis, where an increased concentration gradient causes water molecules to migrate out from food materials into hypertonic solutions more quickly (Omar et al., 2020). Reducing sugar intake could have unintended side effects such as excessive shrinkage or structural collapse of sweet potato slices; dehydration effectiveness must be balanced against high-quality products for best results. Temperature was an integral component in controlling osmotic hydration; higher temperatures between 30°C and 60°C resulted in greater degrees and rates of dehydration for all levels tested. As temperatures increased from 30°C to 60°C, dehydration efficiency improved across all sugar concentrations tested; at higher temperatures, the viscosity of sugar solutions was reduced, which improved mass transfer rates, while water molecules gained energy through friction, which assisted their migration away from sweet potato slices at elevated temperatures. 60°C was found to have the highest dehydration rates when combined with 50 and 60% sugar solutions. While higher temperatures may increase dehydration efficiency, they must still be used carefully to avoid adverse consequences (Jany et al., 2016; Potatoes et al., 2023). Blanching significantly improved the osmotic dehydration process. Blanched samples exhibited higher water loss and solid gain than unblanched ones across all sugar concentrations and temperatures. Blanching disrupts the cellular structure, increasing membrane permeability and facilitating faster water diffusion and solute absorption. Neutralizing enzymes responsible for browning dehydrated products were particularly successful at neutralizing enzymes responsible for browning at higher sugar concentrations and temperatures (50, 60, and 80%) with temperatures reaching 50°C and 60°C. Unblanched samples experienced slower dehydration rates due to Table 3: Water loss over time at various temperatures and sugar solution concentrations for 5mm thick sweet potato slices (var. local sada) Pa ge 81 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 wall-like cells offering resistance against water diffusion (Rastogi, 2023). However, cell membranes in samples that were not blanched acted as barriers, slowing the dehydration process. A mixture of 60% sugar solution at 60°C and blanched samples resulted in maximum water loss, demonstrating its effectiveness as an efficient dehydration method. Unblanched samples treated with 40 % sugar solution at 30°C experienced minimal water loss due to reduced osmotic pressure variation and temperature-driven diffusion. These findings highlight the importance of an efficient strategy for optimizing osmotic dehydration processes that prioritize effectiveness and quality products (Rashid et al., 2020). Effect of Sugar Solution Concentration, Temperature, and Blanching on Dehydration Behavior of 5 mm Sweet Potato (var. Kamala Sundari) Sada and Kamala Sundari varieties were investigated for dehydration behavior when subjected to various sugar concentrations (40 %, 50%, 60% and 60 %), temperatures, and pretreatment conditions (blanched and non-blanched). Both varieties displayed that higher sugar concentrations and temperatures increased water loss through dehydration by osmosis; however, each variety showed different rates and amounts of dehydration. Kamala Sundari displayed slower dehydration rates than Local Sada because of its larger cells, which could aid in resisting the diffusion of moisture more efficiently. Blanching aided in dehydration for both kinds, but Kamala Sundari showed greater structural strength, while local Sada was more susceptible to collapse and shrinkage (Table 4). Comparative analyses of two varieties show how their distinct characteristics affect dehydration. Despite similar processing conditions, Kamala Sundari was better at preventing dehydration while maintaining its unique characteristics than Sada from the local farm. Kamala Sundari varieties with skins that were not blanched showed slower but more even dehydration that preserved the sensory and texture throughout dehydration, highlighting Table 4: Water loss over time at various temperatures and sugar solution concentrations for 5mm thick sweet potato slices (var. kamala sundari) Pa ge 82 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 the importance of adjusting dehydration parameters to specific types of sweet potatoes. By tailoring the conditions for the specific variety, it is possible to get optimal results for dehydration without suffering adverse side effects like excessive shrinkage and loss of nutrients, which ultimately enhance sweet potato’s use in food services (Corrêa et al., 2017). Mass Transfer Behavior Kinetics of Solid Gain in 3mm Thick Sweet Potato Slices (var. Local Sada) During Osmotic Dehydration The study aimed to determine the impact of sugar concentration, temperature, and the pre-treatment of the sample (blanched as opposed to. not blanched) on the behavior of mass transfer in 3mm-thick slices of sweet potato (var. Local Sada) in the course of the dehydration process, which took place over a 4-hour duration (Table 5). The study was carried out with 40, 50%, and 60% sugar solutions and temperatures ranging between 40°C and 60°C. The process of osmotic dehydration is intrinsically time- dependent. Understanding the dynamics of time in the loss of water and gain of solids is essential for determining the optimal treatment parameters (Mari et al., 2024). The results show an increase in sugar solution concentration had a significant impact on the mass transfer rate, specifically in terms of loss of water and gain. The water removal rate was quite low with a sugar concentration of 40 in the sample compared to 50 and 60 %. This could be due to the greater Osmotic pressure gradient produced from the concentrated solution, which draws water out of sweet potato slices more efficiently. In particular, that solution with 60% sugar showed the highest water loss in all temperatures. However, it is important to remember that higher sugar concentrations led to a higher gain in solids (sugar uptake) through sweet potato slices. This is to be expected because the force for the diffusion of solutes into food items is increased with sugar concentration. While this can improve the sweetness and preservation potential of the food item, the excessive gain in solids could negatively impact sensory qualities like texture and taste (Silva et al., 2014). In the initial stages of the osmotic dehydration process (approximately 60-90 minutes), the loss of water and gain in solids occurred rapidly. This can be explained by the pronounced concentration gradient between slices of sweet potato and the supertonic sugar solution that causes water dispersal from the samples and the influx of solutes. When sugar concentrations were higher (50 % and 60 %) and higher temperature (50°C or 60°C) this initial phase was more evident as blanched samples showed greater mass transfer rates compared to the unblanched samples. The temperature played an important role in determining the speed and amount of mass loss during Osmotic dehydration. As temperatures increased from 40°C up to 60°C, both water loss and solid gain accelerated in all sugar concentrations. This is explained by two primary reasons: higher temperatures reduce the viscosity of sugar solution, increasing the mass transfer rate. The higher temperatures enhance the energy of the kinetic energy of solute and water molecules, making it easier for them to move through the cell membranes of slices of sweet potato (Pang et al., 2021; Rastogi, 2023; Mari et al., 2024). Notably, the highest levels of loss of water and solid gain were seen at temperatures of 60°C, specifically when combined with 50% or 60% sugar solutions. However, exposure for a long time to extreme temperatures can cause undesirable consequences like over-shortening, collapse of the structure, or degrading of heat-sensitive nutrients. So, even though increased temperatures Pa ge 83 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 improve the efficiency of mass transfer, however, they should be monitored to avoid negative consequences on the quality of the product (Mari et al., 2024; Aćimović, 2024). The study revealed distinct variations in mass transfer behavior between unblanched and blanched samples. Blanching, a pre-treatment involving short exposure to steam or hot water, appears to improve the permeability of sweet potato’s cell structure, permitting faster water removal and more solid gain when dehydration occurs via osmosis. This effect was especially evident when sugar concentrations were higher (50 % and 60 %) and at higher temperatures (50°C or 60°C). The unblanched samples had a lower rate of loss of water and solid gain, possibly because their cell walls were intact, which were more resistant to mass transport. While blanching increased the efficiency of dehydration, it could have caused some loss of soluble solids during the pre-treatment process, as was observed in earlier studies. This is a trade-off between dehydration speed and the retention of nutrients, which should be considered when selecting the pretreatment methods (Peng & Berry, 2018). The interaction between sugar content and temperature and sample types (blanched instead of unblanched) showed complex dynamics. Combining 60% sugar solution and a temperature of 60°C produced the highest % ages of water loss and solid gain. However, this is not ideal for preserving sweet potato slices’ nutritional and sensory qualities. The blanched samples benefited more at higher temperatures than non-blanched ones, highlighting the necessity of tailoring the processing conditions to the unique nature of raw materials. These findings indicate the necessity of a comprehensive approach to maximizing osmotic dehydration processes, considering both the effectiveness and quality of the product (Osae et al., 2024). Table 5: Solid gain dynamics in 3mm thick sweet potato slices (var. local sada) Kinetics of Solid Gain in 3mm Sweet Potato Slices (var. Kamala Sundari) During Osmotic Dehydration Dehydration characteristics of sweet potato slices from two varieties, Sada and Kamala Sundari, were studied under different sugar concentrations (40%, 50%, and 60%), temperatures, and pre-treatment methods (blanched and unblanched). Higher sugar concentrations and temperatures significantly increased both types’ water Pa ge 84 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 loss and solids gain. There were slight variations between their rates and intensities of dehydration; Kamala Sundari showed significantly slower dehydration rates due to its cell structure and retention characteristics compared with Local Sada. Blanching increased dehydration efficiency for both types, yet Kamala Sundari had greater structural integrity, while Local Sada was more susceptible to swelling and collapse. Even though processing conditions were similar, Kamala Sundari displayed more precise dehydration methods that preserved texture and quality than local Sada. Kamala Sundari samples that had not been blanched showed slower yet more stable dehydration while maintaining taste quality, indicating the need to adjust osmotic dehydration parameters for specific varieties of sweet potatoes (Table 6). Utilizing optimal conditions based on a variety of characteristics can assist in reaching desired dehydration outcomes without unintended side effects such as excessive shrinkage or loss of nutrients, expanding sweet potato’s food-related applications (Rastogi, 2023). Table 6: Solid gain dynamics in 3mm thick sweet potato slices (var. kamala sundari) Kinetics of Solid Gain in 5mm Thick Sweet Potato Slices (var. Local Sada) During Osmotic Dehydration Results demonstrate that increasing sugar solution concentration significantly alters mass transfer behavior, particularly regarding water loss and solid gain. At 40% sugar concentration there was less water removed compared to 50% and 60% concentrations due to higher osmotic pressure gradients created by more concentrated solutions creating an effective gradient to draw moisture away from sweet potato slices more effectively (Table 7). Of all temperature conditions studied, 60% sugar solution demonstrated the greatest water loss. However, it should be noted that higher sugar concentrations also led to an increase in solid gain (sugar uptake) by sweet potato slices, expected as solute diffusion increases with sugar concentration. Although increasing solid gain may enhance the sweetness and preservation potential of the product, excessive solid accumulation may have adverse impacts on sensory qualities such as texture and flavor (Antonio et al., 2008; Sarker et al., 2023). Temperature was an essential component in determining the rate and extent of mass transfer during osmotic dehydration, with both water loss and solid gain increasing exponentially between 40°C and 60°C for all sugar concentrations. Higher temperatures decrease viscosity of sugar solution and improve mass transfer rates, while Pa ge 85 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 increasing water and solute molecules’ kinetic energies to assist them in passing across sweet potato slices’ cell membranes more freely. At 60°C, the highest water loss and solid gain rates were observed, especially when combined with 50% and 60% sugar solutions. More prolonged exposure to higher temperatures can produce adverse side effects, including excessive shrinkage or structural collapse and degradation of heat-sensitive nutrients. While higher temperatures improve mass transfer efficiency, they must also be managed carefully to avoid adverse consequences on product quality (Wu et al., 2020). Experiments have revealed significant variations in mass transfer behavior between blanched and unblanched samples. Blanching, which involves short exposures to hot water or steam, appears to increase the cell structure permeability of sweet potatoes, leading to faster water removal and higher solid gain during osmotic dehydration. This effect was particularly visible at higher sugar concentrations (50% and 60%) and temperatures between 50°C and 60°C, where unblanched samples showed slower rates of water loss and solid gain due to their intact cell walls’ more excellent resistance to mass transference. Blanching may increase dehydration efficiency yet can result in the loss of some soluble solids during pre-treatment, according to previous studies (Rashid et al., 2020; Wu et al., 2020; Kwaw et al., 2023; Rastogi, 2023; Ahmad & Zaidi, 2023). Interactions among sugar concentration, temperature, and sample type (blanched vs. unblanched) revealed intricate dynamics. At 60% sugar solution and 60°C, water loss was highest while solid gain was greatest; however, this combination may not be optimal in preserving sensory and nutritional attributes of sweet potato slices. Blanched samples showed greater benefit from higher temperatures than unblanched samples, emphasizing the significance of adapting processing conditions according to each material’s specific properties. These interactions underscore the necessity of taking a holistic approach when optimizing osmotic dehydration processes, taking both efficiency and product quality into consideration (Lagnika et al., 2021). For applications requiring rapid dehydration and increased sweetness, such as fruit Table 7: Solid gain dynamics in 5mm thick sweet potato slices (var. kamala sundari) Pa ge 86 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 preservation or intermediate moisture food production, using a 60% sugar solution at 50°C-60°C with blanched samples would be most efficient. On the other hand, milder conditions (e.g., 40%-50% sugar solution at 40°C-50°C with unblanched samples) may be preferable. Kinetics of Solid Gain in 5mm Thick Sweet Potato Slices (var. Kamala Sundari) During Osmotic Dehydration Dehydration behavior of 5mm Sweet Potato slices from Local Sada was evaluated using different sugar solution concentrations (40%, 50% and 60%), temperatures and pre-treatment conditions (blanched vs unblanched). Higher sugar concentrations and elevated temperatures significantly accelerated water loss through osmotic dehydration; thicker 5mm slices showed slower dehydration rates due to longer diffusion paths for moisture removal (Table 8). Blanching improved dehydration efficiency by increasing cell permeability but led to greater softening and structural collapse than unblanched samples which retained better texture even at slower dehydration rates (Mari et al., 2024). Comparison between blanched and unblanched 5mm slices illustrates the trade-offs between dehydration speed and product quality. Blanching may speed mass transfer more rapidly, yet its use compromises the structural integrity of slices that are more easily prone to breakage. Unblanched slices showed a more gradual and controlled dehydration process, which better protected their physical properties than that of blanching did - as reported by Neri et al. (2011). These results highlight the significance of optimizing processing conditions based on slice Table 8: Solid gain dynamics in 5mm thick sweet potato slices (var. kamala sundari) thickness and pretreatment to strike an equilibrium between efficiency and quality, increasing sweet potato applications such as intermediate moisture foods or fruit preservation while maintaining their desirable sensory attributes (Rindang et al., 2024). Practical Implications and Industrial Relevance This study’s results have far-reaching ramifications for food processing industries worldwide. By studying the effects of sugar concentration, temperature, slice thickness, and pre-treatment on osmotic dehydration kinetics, our findings provide a solid framework for process optimization in industrial settings. Specifically, designed dehydration systems could maximize efficiency while protecting quality sweet potato products. Examples of optimal conditions identified (using a 60% Pa ge 87 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 sugar solution at 50-60°C for blanched 3 mm slices, for instance) can be scaled up using continuous processing systems equipped with temperature-controlled baths and high-efficiency peristaltic pumps; such systems will ensure consistent product quality, reduce energy consumption, and reduce postharvest losses while simultaneously minimizing postharvest losses. Additionally, this method could serve as a model for dehydrating other moisture crops while broadening industrial applications. Future efforts should focus on conducting small-scale experiments and economic feasibility analyses to test the scalability of optimized conditions; additionally, integrating modern control systems for process management can further increase efficiency while maintaining quality throughout commercial operations. CONCLUSIONS The study provides a thorough understanding of the osmotic degradation behavior of slices of sweet potato focused on two kinds (local Sada as well as Kamala Sundari) and various parameters like sugar concentration in the solution (40, 50 60, 80%) as well as temperatures and slices’ thickness (3 mm or 5 mm) and the pre-treatment conditions (blanched as opposed to. non-blanched). The results highlight the crucial importance of these variables in determining the effectiveness of dehydration and solid gain as well as the quality of the product. The higher sugar levels and the elevated temperatures generally increased water loss and solid gain in all tests. However, differences between the different species were apparent in Kamala Sundari, which showed slower but controlled dehydration than Local Sada, which demonstrated higher removal of moisture but higher vulnerability to the collapse of the structure. Slice thickness had a significant impact as thin slices (3 mm) dehydrated faster than those with thicker slices (5mm); however, the latter exhibited better structural integrity throughout processing. Blanching has been found to accelerate dehydration through increasing cell permeability, but it also weakened texture, particularly in smaller slices and the Local Sada type. Although less prone to drying, the samples that were not blanched maintained more physical characteristics, making them suitable for use in applications where texture is essential. These findings highlight the importance of adjusting the dehydration parameters, including the sugar content, temperatures, and pre-treatment, to the unique features of sweet potato varieties and the desired characteristics of the product. The study provides valuable insights for the food processing industry by optimizing osmotic dehydration conditions for specific sweet potato varieties, reducing post-harvest losses, and enhancing product quality. These findings also apply to other high-moisture crops, broadening food preservation strategies. Future research should explore alternative osmotic agents, integrate advanced drying techniques, and assess the economic feasibility of industrial-scale implementation. This study advances food dehydration science, offering practical guidance for both research and industry applications. REFERENCES Aćimović, M. (2024). Osmotic Treatment of Orange and Pink Sweet Potato-Mass. 18(3), 59–68. Ahmad, F., & Zaidi, S. (2023). The influence of ultrasound-assisted osmotic dehydration as a pre- treatment method on the quality of vacuum dried pineapple. Food and Humanity, 1(January), 137–146. https://doi.org/10.1016/j.foohum.2023.05.004 Antonio, G. C., Alves, D. G., Azoubel, P. M., Murr, F. E. X., & Park, K. J. (2008). Influence of osmotic dehydration and high temperature short time processes on dried sweet potato (Ipomoea batatas Lam.). Journal of Food Engineering, 84(3), 375–382. https://doi.org/10.1016/j.jfoodeng.2007.05.033 Araújo, A. L. de, & Pena, R. da S. (2023). Combined Pulsed Vacuum Osmotic Dehydration and Convective Air-Drying Process of Jambolan Fruits. Foods, 12(9), 1–18. https://doi.org/10.3390/foods12091785 Balladin, D. A., & Headley, O. (1999). Evaluation of solar dried thyme (Thymus vulgaris Linné) herbs. Renewable Energy, 17(4), 523–531. https://doi.org/10.1016/ S0960-1481(98)00757-5 Cheng, X., Wang, S., Shahid Iqbal, M., Pan, L., & Hong, L. (2023). Effect of ultrasound-assisted osmotic dehydration on the drying kinetics, water state, and physicochemical properties of microwave vacuum-dried potato slices. Ultrasonics Sonochemistry, 99(July), 106557. https://doi.org/10.1016/j. ultsonch.2023.106557 Corrêa, J. L. G., Rasia, M. C., Mulet, A., & Cárcel, J. A. (2017). Influence of ultrasound application on both the osmotic pretreatment and subsequent convective drying of pineapple (Ananas comosus). Innovative Food Science and Emerging Technologies, 41(November 2016), 284–291. https://doi.org/10.1016/j.ifset.2017.04.002 de Souza Silva, K., Caetano, L. C., Garcia, C. C., Romero, J. T., Santos, A. B., & Mauro, M. A. (2011). Osmotic dehydration process for low temperature blanched pumpkin. Journal of Food Engineering, 105(1), 56–64. https://doi.org/10.1016/j.jfoodeng.2011.01.025 Dermesonlouoglou, E., Seretis, G., Katsouli, M., Katsimichas, A., Taoukis, P., & Giannakourou, M. (2025). Effect of Pulsed Electric Fields and Osmotic Dehydration on the Quality of Modified-Atmosphere- Packaged Fresh-Cut and Fried Potatoes. Foods, 14(3). https://doi.org/10.3390/foods14030420 Genina-Soto, P., Barrera-Cortes, J., Gutierrez-Lopez, G., & Nieto, E. A. (2001). Temperature and concentration effects of osmotic media on OD profiles of sweet potato cubes. Drying Technology, 19(3–4), 547–558. https://doi.org/10.1081/DRT-100103933 Jain, D. K., & Chauhan, O. P. (2022). Development of Osmotically Dehydrated Sweet Potato ( Ipomoea batatas ( L .) Lam .) Slices Incorporated with Pineapple Juice and Evaluation of its Chemical and Nutritional Properties. 2(2), 115–128. Jany, M. N. H., Mazumder, M. A. R., & Uddin, M. B. (2016). Effect of varietal differences on the osmotic dehydration of sweet potatoes (Ipomoea batatas Pa ge 88 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 Lam). International Journal of Agricultural and Food Science, 6(2), 4–18. Kadir, N., Yeasmen, N., Bhuiyan, M. H. R., Khan, M. J., & Iqbal, A. (2024). Osmotic and convective hot air drying of sweet gourd. Food Science and Biotechnology, 33(2), 363–374. https://doi.org/10.1007/s10068- 022-01193-x Kwaw, E., Osae, R., Apaliya, M. T., Alolga N, R., Sackle Sackey Aikins, A., Olivia, A., Nancy, A., & Veronica, O. (2023). Influence of different osmotic dehydration pretreatment on the physiochemical and sensory characteristics of fried cassava chips (Manihot esculenta). Journal of Agriculture and Food Research, 12(March), 1–6. https://doi.org/10.1016/j. jafr.2023.100613 Lagnika, C., Riaz, A., Jiang, N., Song, J., Li, D., Liu, C., Wei, Q., & Zhang, M. (2021). Effects of pretreatment and drying methods on the quality and stability of dried sweet potato slices during storage. Journal of Food Processing and Preservation, 45(10). https://doi. org/10.1111/jfpp.15807 Malakar, S., Manonmani, T., Deb, S., & Dash, K. K. (2021). Osmotic Dehydration in Food Processing. Food Processing, 67–89. https://doi. org/10.1201/9781003163213-4 Mari, A., Andriotis, P., Drosou, C., Laina, K. T., Panagiotou, N., & Krokida, M. (2024). Enhancing Shelf-life Stability of Refrigerated Potatoes through Osmotic Dehydration and Ohmic Heating Optimization: A Strategy to Mitigate Enzymatic Browning. In Potato Research (Issue 0123456789). Springer Netherlands. https://doi.org/10.1007/s11540-024-09805-1 Nath, S., & Sil, S. (2008). Preservation and storage of perishable fresh fruits and vegetables in the lowlands of Papua New Guinea. AMA, Agricultural Mechanization in Asia, Africa and Latin America, 39(4), 75–80. Neri, L., Hernando, I. H., Pérez-Munuera, I., Sacchetti, G., & Pittia, P. (2011). Effect of Blanching in Water and Sugar Solutions on Texture and Microstructure of Sliced Carrots. Journal of Food Science, 76(1), 1–2. https://doi.org/10.1111/j.1750-3841.2010.01906.x Omar, S. R., Razak, S. A., & Ramly, N. Z. (2020). Texture analysis of starfruit (Averrhoa carambola) chips pre- treated with glucose syrup and osmotic dehydration. Malaysian Applied Biology, 49(3), 123–127. https://doi. org/10.55230/mabjournal.v49i3.1555 Osae, R., Adjonu, R., Apaliya, M. T., Engmann, F. N., Owusu-Ansah, P., Fauzia, A. S., Otoo, G. S., Kwaw, E., & Alolga, R. N. (2024). Freeze-thawing and osmotic dehydration pretreatments on physicochemical properties and quality of orange-fleshed sweet potato slice during hot air drying. Food Chemistry Advances, 5(October 2022), 100843. https://doi.org/10.1016/j. focha.2024.100843 Otálora, A., García-Quintero, A., Mera-Erazo, J., Lerma, T. A., Palencia, M., & Mercado, T. (2024). Sweet potato, batata or camote' (Ipomoea batatas): An overview about its crop, economic aspects and nutritional relevance. Journal of Science with Technological Applications, 17(October), 1–10. https://doi.org/10.34294/j. jsta.24.17.100 Pandiselvam, R., Tak, Y., Olum, E., Sujayasree, O. J., Tekgül, Y., Çalışkan Koç, G., Kaur, M., Nayi, P., Kothakota, A., & Kumar, M. (2022). Advanced osmotic dehydration techniques combined with emerging drying methods for sustainable food production: Impact on bioactive components, texture, color, and sensory properties of food. Journal of Texture Studies, 53(6), 737–762. https://doi.org/10.1111/jtxs.12643 Pang, L., Lu, G., Cheng, J., Lu, X., Ma, D., Li, Q., Li, Z., Zheng, J., Zhang, C., & Pan, S. (2021). Physiological and biochemical characteristics of sweet potato (Ipomoea batatas (L.) Lam) roots treated by a high voltage alternating electric field during cold storage. Postharvest Biology and Technology, 180(May), 111619. https://doi.org/10.1016/j.postharvbio.2021.111619 Peng, W., & Berry, E. M. (2018). The concept of food security. In Encyclopedia of Food Security and Sustainability (Vol. 2). Elsevier. https://doi.org/10.1016/B978-0- 08-100596-5.22314-7 Potatoes, D. F., Dadashi, S., Javid, N., Heshmati, M. K., & Dehghannya, J. (2023). Dehydration on Physical and Impact of Coating and Osmotic Dehydration on Physical and Microstructural Properties of Deep- Fat Fried Potatoes. https://doi.org/10.20944/ preprints202311.1261.v1 Rashid, M. T., Jatoi, M. A., Safdar, B., Wali, A., Aadil, R. M., Sarpong, F., & Ma, H. (2020). Modeling the drying of ultrasound and glucose pretreated sweet potatoes: The impact on phytochemical and functional groups. Ultrasonics Sonochemistry, 68(March), 105226. https:// doi.org/10.1016/j.ultsonch.2020.105226 Rastogi, N. K. (2023). Developments in osmotic dehydration of foods. In Drying Technology in Food Processing: Unit Operations and Processing Equipment in the Food Industry. Elsevier Inc. https://doi.org/10.1016/ B978-0-12-819895-7.00015-8 Rinaldo, D. (2020). Carbohydrate and bioactive compounds composition of starchy tropical fruits and tubers, in relation to pre and postharvest conditions: A review. Journal of Food Science, 85(2), 249–259. https://doi.org/10.1111/1750-3841.15002 Rindang, A., Mardjan, S., Darmawati, E., Hartulistiyoso, E., & Ahmad, U. (2024). Study on Mass Transfer and Physicochemical Properties of Avocado During Osmotic Dehydration. Trends in Sciences, 21(12). https://doi.org/10.48048/tis.2024.8567 Sarker, A., Ahmmed, R., Ahsan, S. M., Rana, J., Ghosh, M. K., & Nandi, R. (2023). A comprehensive review of food waste valorization for the sustainable management of global food waste. Sustainable Food Technology, 2(1), 48–69. https://doi.org/10.1039/ d3fb00156c Silva, K. S., Fernandes, M. A., & Mauro, M. A. (2014). Effect of calcium on the osmotic dehydration Pa ge 89 https://journals.e-palli.com/home/index.php/ajfst Am. J. Food. Sci. Technol. 4(1) 76-89, 2025 kinetics and quality of pineapple. Journal of Food Engineering, 134, 37–44. https://doi.org/10.1016/j. jfoodeng.2014.02.020 Šovljanski, O., Lončar, B., Pezo, L., Saveljić, A., Tomić, A., Brunet, S., Filipović, V., Filipović, J., Čanadanović- Brunet, J., Ćetković, G., & Travičić, V. (2024). Unlocking the Potential of the ANN Optimization in Sweet Potato Varieties Drying Processes. Foods, 13(1). https://doi.org/10.3390/foods13010134 Wang, J., Bi, J., Wang, F., & Lyu, J. (2025). Effect of osmotic dehydration with binary/ternary sugar solutes on macro-& micro-structure, chromaticity and thermal stability of dehydrated peach slices prepared by heat pump drying. Food Chemistry, 468(December 2024), 142487. https://doi.org/10.1016/j.foodchem.2024.142487 Wu, X. fei, Zhang, M., Ye, Y., & Yu, D. (2020). Influence of ultrasonic pretreatments on drying kinetics and quality attributes of sweet potato slices in infrared freeze drying (IRFD). Lwt, 131(July), 109801. https:// doi.org/10.1016/j.lwt.2020.109801