Search

Solar drying systems are becoming a popular alternative to traditional energy-based drying systems for agricultural products due to their effectiveness and reduced fuel consumption. Although the efficiency of solar drying systems has been thoroughly investigated, their sustainability has not been studied enough. This study aims to fill that gap by conducting a life-cycle assessment of two new solar drying systems built in Udaipur, Rajasthan, India. The environmental implications of an innovative cylindrical solar-assisted drying system and a phase-change material-based solar drying system were evaluated using cradle-to-gate life-cycle analysis. The study uses the ReCiPe 2016 endpoints (H) technique to calculate various aspects such as midpoint, endpoint, single score, normalization result, and network diagram for phase-change material-based solar drying and cylindrical solar-assisted drying. Results show that phase-change material-based solar drying has an average of 40% more impact on the environment than cylindrical solar-assisted drying, with a high impact found in human non-carcinogenic toxicity, mainly due to the production of phase-change materials. However, cylindrical solar-assisted drying system crossover phase-change material based solar drying in terms of its impact on human carcinogenic toxicity and fossil resource scarcity. The contribution to global warming of phase-change material-based solar drying is 13.7% more than that of cylindrical solar-assisted drying. The endpoint characterization indicates that phase-change material-based solar drying exceeds in terms of human health (40%) and ecosystem (37.04%), whereas cylindrical solar-assisted drying surpasses phase-change material-based solar drying in terms of impacts on resources, at 14%. The early drying in phase-change material-based solar drying makes up for its higher impact than that in cylindrical solar-assisted drying, which takes 3 hours longer to dry. This study offers guidance and methods for making the best choice of solar-powered dryers. [ABSTRACT FROM AUTHOR]

Cissus quadrangularis is an extensively utilized medicinal plant in India which has numerous health benefits. Hence, the drying kinetics of Cissus was studied using fluidized bed dryer to identify suitable drying conditions and to understand moisture removal and its connection to process variables. The present research aimed to determine a suitable drying model of fluidized bed drying of Cissus quadrangularis Linn., determine the effective moisture diffusivity of the drying process and the activation energy, and investigate the effects of temperatures on the drying kinetics of Cissus. The drying experiments were conducted at three different air temperatures (40, 50 and 60 °C), bed thickness of 5 cm, constant air velocity of 8 m/s and 0.5-1 cm length Cissus samples. The experimental drying data was fit into thirteen thin layer models and the best model describing the drying of Cissus was selected based on the correlation coefficient (R), root mean square error (RMSE), and reduced chi-square (X2). The drying process occurred in a falling rate period for all the drying air temperatures and a constant rate period was not observed. Among all the thirteen models tested, approximation of diffusion was found to explain the thin layer drying behavior of C. quadrangularis accurately. The effective moisture diffusivity for Cissus was in the range of 1.54 - 3.12x 10-10 m²/s and the activation energy was 30.76 kJ/mole, respectively. Hence, fluidized bed drying is more effective for convective drying of Cissus and the drying models are useful for selecting the best operational condition for fluidized bed dryer and design of an equipment. [ABSTRACT FROM AUTHOR]

The experiment was carried out in the laboratories of the Department of Food Engineering and the Department of Plantation Spices Medicinal & Aromatic Crops, and the Central Horticultural Laboratories, Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India during 2018-2019 and 2019-2020. With an objective of study the performance of drying methods at different temperatures on physical and quality parameters of dry chilli. The experiment was conducted in Randomized Complete Block Design (RCBD) replicated thrice with seven treatments of different drying methods viz., sun drying, solar drying and oven drying at 50°C, 55°C, 60°C, 65°C and 70°C. The experimental results were maximum fruit length (7.00 cm), fruit diameter (10.22 mm), chroma (38.13), minimum total color difference (11.82) and browning index minimum (85.81) were found in the oven drying at 65oC and the fruit weight (0.81 g) was maximum observed in the sun drying method. However, the minimum bulk density (0.31 g cc-1) and the maximum dehydration ratio (3.88) were detected by oven drying at 70°C. The highest ß-carotene content (224.41 µg 100 g-1) was observed during oven drying at 50°C, where as minimum ß carotene content was recorded by sun drying. In sun drying method low quality due to oxidation as the dried chilli was exposed directly to light and sun. An increase in drying air temperature and long period of drying time has a negative effect on quality of dry chilli. [ABSTRACT FROM AUTHOR]

Hand hygiene remains one of the most effective methods of preventing healthcare-associated infections. Hand drying is the end point of hand hygiene. Hand drying after hand hygiene is less explored, and the practice varies in different facilities. This explorative study was done to know the various hand-drying methods and practices of healthcare workers in Indian settings. This was a descriptive cross-sectional questionnaire-based observational study initiated from a tertiary care setup in Uttarakhand. Healthcare workers over 18 years of age directly involved in patient care were enrolled. A semi-structured questionnaire with both open-ended and close-ended questions was used with snowballing sampling technique. Statistical analysis was done using Statistical Package for Social Sciences (SPSS). Out of the eligible 395 respondents, 62.8% were female. The mean age of the respondents was 31.34 ± 8.44 years and average working hours were 8.87 ± 2.97 (range 4-24) hours. Only 72.7% did hand hygiene always before touching a patient. Nurses were more compliant about hand hygiene than doctors (P < 0.0001). A total of 82.8% were aware of appropriate hand-drying methods. Staff in the Intensive care unit Intensive care unit (ICU) setup were more aware of hand drying practices (P = 0.033). A total of 21.8% wiped their hands on their clothing to dry their hands. This was more in staff from paraclinical departments (P = 0.001). A total of 35.7% used handkerchiefs to dry hands. Resident doctors used handkerchiefs more than senior doctors or nursing staff (P = 0.01). A total of 49.9% of respondents spent less than 10 seconds in hand drying. Hand-hygiene knowledge is high among healthcare workers in India, but the knowledge of appropriate hand-drying practices is lacking. There is wide variation in the practice of hand drying. Better hand drying guidelines and incorporating hand drying as the essential endpoint of the hand hygiene ritual are warranted. [ABSTRACT FROM AUTHOR]

Spray drying is a widely used technique for production of milk powder. This is a high level energy consumption process. There are scanty published studies on single-stage spray drying plant for skim milk powder production. In this study, thermodynamic analyses, i.e., energy and exergy analyses and exergoeconomic analysis of single stage spray drying unit has been executed for skim milk powder production. The analyzed parameters are specific exergy destruction ratio, exergy efficiency, relative irreversibility factor, energy improvement potential, exergy improvement potential, specific energy destruction ratio, energy efficiency, and relative energy destruction ratio. The energy and exergy equations were used for computation of these parameters. The energy efficiency and exergy efficiency of plant were computed as 89.63 and 49.19%, respectively. The energy and exergy improvement potential were maximum for drying chamber followed by booster pump, which indicated that there was vast scope in the technical improvement for drying chamber. Highest cost of processing was obtained for drying chamber (percentage relative cost difference: 59.84%) followed by cyclone separator (percentage relative cost difference: 48.98%). Based on these analyses, improvement of high improvement potential components of the spray drying plant may be carried out. [ABSTRACT FROM AUTHOR]

• Drying methods significantly alter Moringa fruit pulp powder's composition, color, and ascorbic acid content. • Freeze-drying maintains maximum moisture, while oven drying minimizes it. • Freeze-dried MPP shows superior whiteness and less browning, ideal for food applications. • Freeze-drying improves water solubility, absorption, total phenol, and flavonoid content in MPP. • Freeze-dried MPP boasts top-notch in vitro antioxidant and antidiabetic activities, promising for functional foods. Moringa oleifera , a medicinal plant of considerable interest, has been extensively studied for its leaves' functional properties, while its pods have received relatively less attention, despite being widely consumed in India and other regions. This study investigates the effect of various drying methods on the crude composition, color, ascorbic acid content, water solubility, water absorption, total phenol content, total flavonoid content, and in vitro antioxidant and antidiabetic activities of Moringa pod pulp powder (MPP). The study reveals significant variations in the proximate composition, color attributes, and bioactive compounds of MPP resulting from freeze drying, microwave drying, oven drying, and sun drying methods. Freeze drying preserves the highest moisture content, while oven drying results in the lowest. Carbohydrate, protein, fat, ash, and crude fiber contents remain consistent across all drying methods, confirming MPP's nutritional value. Furthermore, freeze drying leads to higher ascorbic acid retention, highlighting its effectiveness in preserving this essential vitamin. The study demonstrates that freeze drying enhances water solubility, water absorption, total phenol content, and total flavonoid content in MPP. Notably, freeze dried MPP exhibits the highest in vitro antioxidant activity and antidiabetic potential, with significant α-amylase, α-glucosidase, and ACE inhibition properties. The findings underscore the importance of drying methods in preserving the quality and bioactive compounds of MPP, making it a valuable ingredient for various applications in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Sea cucumbers, members of the echinoderm class Holothuroidea, are marine invertebrates with ecological significance and substantial commercial value. With approximately 1700 species, these organisms contribute to marine ecosystems through nutrient cycling and face various threats, including overfishing and habitat loss. Despite their importance, they are extensively exploited for diverse applications, from seafood to pharmaceuticals. This study investigates sea cucumbers' nutritional profile and bioactive elements, emphasizing their role as sources of essential compounds with potential health benefits. The demand for sea cucumbers, especially in dried form, is significant, prompting exploration into various drying techniques. Examining the global trade in sea cucumbers highlights their economic importance and the conservation challenges they face. Conservation efforts, such as awareness campaigns and international collaboration, are evaluated as essential steps in combating illicit trade and promoting the sustainable stewardship of sea cucumber populations. Practical Application: Around 1700 species of sea cucumbers were identified as vital ecological scavengers in the Holothuroidea class. High commercial value due to their health benefits, particularly their demonstrated inhibitory effect against various types of cancer. "Beche‐de‐mer" holds a 90% market share and is regarded as a luxury food item in Southeast Asian countries. Due to overexploitation, the species is classified as Schedule I under the Wildlife Protection Act (WPA) in India, prompting the implementation of a blanket ban on their harvesting to ensure its conservation. [ABSTRACT FROM AUTHOR]

• Yacon is rich in polyphenols, fructooligosaccharide which leads browning reactions. • Different pre-drying treatment with anti-browning agents were applied to yacon slices. • Dipping with KMS (0.3%) with citric acid (0.05%) for 20 min was most effective. • Mechanical cabinet drier (60 °C) showed best quality yacon powder with less browning. Yacon (Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson) is a sweet-tasting tuber that is considered a functional food due to its richness in many bioactive compounds like polyphenols, phytoalexins, fructooligosaccharide (FOS), etc. Its full potential has not been utilized in India due to browning problem during its processing and short life span owing to high moisture content so the present study was conducted. The goal of this research was to standardize the optimal pre-drying treatment with the use of different anti-browning agents and drying mode for reducing browning and prolonging shelf life while eliminating unnecessary functional changes. Different pretreatments methods like blanching and dipping methods were analyzed and it was observed that dipping treatment with KMS (0.30%) in combination with citric acid (0.05%) for 20 min followed by drying in mechanical cabinet drier at 60±2 °C showed best quality characteristics of yacon powder with least biochemical changes due to browning. Sensory evaluation also favored the standardized pre-treated yacon powder. Mechanical cabinet drier took least time (7.4 h) to dry as compared to other drying modes. The cabinet drier powder retained highest amount of TSS (81 °B), reducing sugar (39.09%), total sugar (68.82%), carbohydrates (74.07%), proteins (0.78%), ascorbic acid (22.95 mg/100 g), total phenols (309.72 mg/100 g), antioxidant activity (93.80%), rehydration ratio (5.40) and L* value (68.93). While the same powder retained least amount of moisture (4.31%), a w (0.203), yield (11.12%), NEB (0.06), HMF (1.43 ppm), furfural (0.018ppb), ash (3.55%) and acid insoluble ash (0.71%) showed no significant differences. Further, the mechanical cabinet dried powder with very low moisture and water activity which makes it shelf-stable food, received highest sensory scores for various parameters as compared to powder obtained through solar tunnel drier and sun drying. [ABSTRACT FROM AUTHOR]

India like other developing countries adopts many food preservation technologies using fossil fuels. But the fossil fuel resource depletes over the years and is non-renewable. Therefore, solar drying technology is preferred as a sustainable method for food preservation. The present study is aimed at a sustainable livelihood initiative for drying fruits and vegetables through solar technology intervention using an indirect forced convection type solar dryer. Such a dryer of 15 kg capacity has been designed and fabricated for drying mangoes. Performance indicators such as instantaneous collector efficiency, drying efficiency, drying rate, COP, heat utilization factor, and moisture content on a dry basis are evaluated as 59%, 32.25%, 0.15178 kg/hr, 0.77, 0.229, and 2.55, respectively by considering maximum outlet collector temperature, drying chamber temperature and atmospheric temperature. Economic indicators such as pay-back period and cost-benefit ratio are also evaluated as 1.439 and 2.0008, respectively. The dryer can be used by rural people of Odisha for earning their livelihood. [ABSTRACT FROM AUTHOR]

Reversible airflow fixed bed dryer (RAFBD) is an energy‐efficient, cost‐effective, and dependable dryer for using renewable energy sources in parboiling mills. In this study, a medium‐sized and high‐moisture parboiled paddy, ASD‐16, was dried in the RAFBD to determine its deep drying characteristics and thermodynamic properties. The chosen paddy variety is a commonly cultivated paddy in the southern region of Tamil Nadu, India. The RAFBD experimental setup was designed to dry 30 kg of parboiled paddy. For the statistical analysis, the experimental data for the deep‐bed drying at hot air temperatures 50–80°C and velocities of 0.1 and 0.15 m/s were used at constant specific humidity. To predict drying characteristics, 12 drying models were compared. Based on their statistical parameters, the Midilli et al. model was selected. For the tested conditions, the coefficients for effective moisture diffusion, heat transfer, and mass transfer were between 9.82 × 10−8 and 2.13 × 10−7 m2/s, 0.3802 and 1.325 W/m2 K, and 0.375 × 10−4 and 1.26 × 10−4 m/s, respectively. Furthermore, the determined activation energy ranged from 20.4964 to 20.4390 kJ/mol. Practical Applications: ASD‐16 is one of the popular paddy varieties cultivated and used in parboiling mills in the study region. The outcome of this research can contribute to the application of a cost‐effective dryer for drying high‐moisture paddy. Furthermore, the drying time and bed height proposed in this work can reduce the drying time in the mills and improve energy efficiency. The drying kinetics and suitability of the models found in this study will contribute to the design and development of low‐cost dryers for the local parboiling industries. As rice husk, which is a waste from paddy processing, is used for the heating process, industries can reduce the cost of energy for closed‐roof drying. This study provides a clear insight to the researchers and designers in standardizing the capacity of the dryer, drying temperature, and airflow rate for any similar kind of paddy variety. [ABSTRACT FROM AUTHOR]

Accomplishment of an ideal root canal treatment is attributed to various essential factors such as proper instrumentation, chemomechanical preparation, obturation and post endodontic restoration. The main aim of this study is to test the null hypothesis that is the moisture condition of root dentin would not affect the bond strength and sealer penetration. This is an in vitro study conducted in Department of Conservative Dentistry and Endodontics, M A Rangoonwala Dental College, Pune, India over a period of two years (from 2021 to 2023). One hundred and twenty single-rooted Premolars with fully formed apices and similar root morphology were obtained and stored in 0.1% thymol solution. The specimens were randomly assigned to 3 broad experimental groups (n=40) according to the drying protocol such as Group A- Paper points (P), Group B- diode laser (L) and Group C- isopropyl alcohol (A). For each drying protocol, the specimens were further assigned to 2 subgroups (n=20) with respect to the sealers used: AH Plus (AH) and Apexit Plus sealers (APx). The effect of drying protocol using paper points, isopropyl alcohol and diode-lasers on the bond strength and tag penetration of two different sealers to the root dentin was evaluated. Maximum overall push-out Bond strength was seen in group AH+L and least in group APx+ L. Inter-site push-out bond Strength was highest in the coronal third followed by the middle and least in the apical third of all the groups. Maximum over all depth of penetration was seen in group AH+L and minimum in group APx+L. AH plus sealer showed better bond strength, sealer penetration and adaptation to the dentinal walls compared to Apexit plus sealer, irrespective of the drying protocol followed. All the drying protocols used did not show statistically significant results in the apical thirds of root canals of all the groups.

Groundwater in north India remains a vital food and water security resource for more than one billion people. Both summer monsoon drying, and winter warming pose considerable challenges for rapidly declining groundwater. However, their impacts on irrigation water demands and groundwater storage under the observed and projected future climate remain unexplored. Using in situ observations, satellite data, and a hydrological model that considers the role of irrigation and groundwater pumping, we show that summer monsoon drying and winter warming accelerate groundwater depletion in north India during the observed climate, which will continue in the projected future climate. Summer monsoon precipitation has significantly (P‐value = 0.04) declined (∼8%) while winters have become warmer in north India during 1951–2021. Both satellite (GRACE/GRACE‐FO) and hydrological model‐based estimates show a rapid groundwater depletion (∼1.5 cm/year) in north India with a net loss of 450 km3 of groundwater during 2002–2021. The summer monsoon drying followed by winter warming cause a substantial reduction in groundwater storage due to reduced groundwater recharge and enhanced pumping to meet irrigation demands. Summer monsoon drying and winter warming will continue to affect groundwater storage in north India in the future. For instance, summer monsoon drying (10%–15% deficit for near‐far periods) followed by substantial winter warming (1–4°C) in the future will further accelerate groundwater depletion by increasing (6%–20%) irrigation water demands and reducing groundwater recharge (6%–12%). Groundwater sustainability measures including reducing groundwater abstraction and enhancing the groundwater recharge during the summer monsoon seasons are needed to ensure future agricultural production. Plain Language Summary: Groundwater in north India is facing rapid depletion due to summer monsoon drying and winter warming. The decline in summer monsoon precipitation and warmer winters have led to major droughts, resulting in a massive loss of groundwater between 2002 and 2021. Summer monsoon drying coupled with winter warming climate will increase irrigation water demands and reduce groundwater recharge. This necessitates the implementation of groundwater sustainability measures to ensure future agricultural production during monsoon droughts. Key Points: Examined the role summer monsoon drying and winter warming on groundwater storage in IndiaRapid groundwater depletion (∼1.5 cm/year) resulted in a net loss of 450 km3 of groundwater during 2002–2021Summer monsoon drying followed by substantial winter warming under the warming climate will further accelerate groundwater depletion [ABSTRACT FROM AUTHOR]

Effect of temperatures (40, 50, and 60°C) on quality attributes of small cardamom (Elettaria cardamomum Maton) during hot air convective (HAC) drying was investigated. Kinetics of moisture, color and aroma during the HAC drying were analyzed. Among seven 2‐ and 3‐term exponential models, the Logistic model was best‐fitted to the drying data. Moisture transfer rates were found out to be 1.62 × 10−8, 2.51 × 10−8, and 3.64 × 10−8 m2 s−1 at 40, 50, and 60°C, respectively, and the activation energy of diffusion was 34.96 kJ mol−1. When surface color (L*, a*, and b*) and aroma (essential oil yield) were considered as another two quality criteria during the drying of cardamom capsules, samples dried at 50°C was observed to be the best. With drying time, the value of L* decreased, a* value increased, and b* value of cardamom samples increased. Weibull model yielded the higher correlation coefficient between the predicted and the experimental data of color parameters (L* and a*) whereas the Zero‐order model was fitted well for b* values for the entire temperature range. Aroma calculated as essential oil yield (% dry basis) increased with drying time due to the release of a large number of volatile components during the drying. Practical Application: Small cardamom so far is known to have best among the spices in terms of quality. Although India is among the largest consumer and producer of cardamom, cardamom growers adopt the age‐old processing practices. Furthermore, there is the absence of systematic study and scientific understanding in the existing practice of cardamom drying. The existing design and development of a dryer suitable for cardamom capsules are highly dependent on moisture, color, and aroma profile during drying. Studying drying kinetics along with postprocessing quality evaluation such as color and aroma would support as preliminary information for the development of suitable dryers for optimum retention of color and aroma of cardamom capsules during the drying. [ABSTRACT FROM AUTHOR]

The objective of this paper is to develop a universal diffusion model of drying kinetics that can be applied to a variety of shrinkable products such as fruits and vegetables. The main objective is to examine the physical changes that occur during convective air‐drying process of Thompson seedless type cylindrical grapes. These include changes in the physical properties of the product, such as the moisture content, the temperature of the product, and the size of the product. The authors develop a two‐dimensional transient diffusion model and MATLAB that takes into account convection, radiation, and evaporation phenomena under a variety of operating conditions for simulating grape drying and shrinkage. The differential equations are solved for moisture transfer within a cylinder using the finite difference method. A lab‐scale experimental test setup has also been developed and tests are performed. The results obtained from the mathematical model are compared with experimental results and found to be in agreement with a maximum error of 14%. The model is also validated with the results reported in the literature. Meteorological data are used to determine the time‐dependent radiation flux density (I(t)) on a particular day. For each of the investigated conditions, the effective moisture diffusivity (Deff) is determined using Fick's diffusion equation. Volume reduction of a product due to drying process was assumed to be equivalent to moisture removal. A coefficient of effective diffusivity was calculated using drying data collected at constant cabin air temperatures between 50 and 70°C. The maximum radius and length of the grape were reduced by 40.33% and 42.40%, respectively, when the size of the grape was considered to be 6.5 mm radius and 25 mm length. The results of the present mathematical model may be useful for accurately predicting the temperature, moisture content, and size change of the product. Practical Application: Drying food to preserve it is an energy‐intensive process. Solar drying is one of the oldest methods used to preserve agricultural produce. Solar thermal energy has tremendous potential for commercial and industrial drying applications with air temperatures as high as 80°C. Solar drying is prevalent in India because farmers have easy access to solar drying systems. Through the installation of such a system, agricultural products can be dried in agricultural regions. This work provides farmers with added value for their particular products. Solar dryers system ensure significant fossil fuel energy savings. Solar dryers must meet rigorous requirements for dependability and continuous operation. This research contributes to the design, optimization, and control of food drying processes. For each drying time, the extent of moisture distribution, product temperature, and product size are determined. For dryers operating under a variety of operating conditions, this aids in system performance forecasting. In addition, the effect of interior cabin temperature variation is investigated, which aids in identifying drying characteristics. [ABSTRACT FROM AUTHOR]

India is one of the highly developing countries in the world and it has the second-largest agricultural source of income, which covers 61% of the entire income of the country. The most valuable income group, by giving the appropriate training in this technology, will make their entire country to become one of the most highly developing counties in the world. In recent years, many developing, developed, and underdeveloped countries face shortages of fish, fruits, and vegetables due to natural disasters like earthquakes, tsunami, and any other unexpected events. Now the main issue of this paper is to preserve the food products from post-harvest to consumer-level, which cover 60% of losses due to the unavailability of preservative methods. This paper mainly focused on the conventional methods to advanced solar drying technologies for perseverating fish, fruits, and vegetables and also it discusses the technology used for drying the yield range of fish like Atheriniformes, Catfish, Chilwa, etc. Fruits like banana, mango, and papaya, and vegetables like bitter gourd, cabbage, and cocoa beans have been reviewed and also discussed some problems along with their solutions in concern with food products drying, thereby the selection of dryer for drying products will be made easy by this review article. On the whole, this investigation would help researchers in fish drying to choose the better drying methods for acquiring better results for particular fish, fruits, and vegetables that enable any entrepreneur to select the appropriate method reducing the cost and time. [ABSTRACT FROM AUTHOR]

Drying is one of the complex processes, comprising parallel heat and mass transfer reactions. It extends the shelf life of perishable agricultural produces (like green leafy vegetables) by decreasing the level of water activity. In the present work, hot water and ultrasound pretreatments were conducted, prior to the dehydration of fresh morisa xak (Amaranthus caudatus) leaves by microwave drying for improving color stability. In order to assess the color degradation kinetics of chlorophyll, the impact of drying techniques on hunter color parameters (L*, a*, b*) and total color difference (TCD) has been evaluated. Thermal degradation of chlorophyll of the green leaves followed the first order kinetics and Arrhenius equation was employed to describe the temperature dependence of the reaction rate constant. From the study, the protective effect of ultra sound pretreatment on the color stability of morisa xak leaves prior to microwave drying can be observed. Practical Applications: Morisa xak is popular and an important green leaves consumed by North Eastern Part of India. As it has high moisture content, morisa xak leaves has been prone to deterioration during post‐harvest storage. Microwave drying has been preferred over traditional hot air drying method due to its high drying rates and better drying quality. As chlorophyll is the main coloring pigment in green leaves, its deterioration is very common during drying. In the current investigation, different pre‐treatments (hot water and ultra sound) were applied to morisa xak leaves before microwave drying to improve the chlorophyll content. The results of the study indicated that the application of ultra sound pretreatment before microwave drying could be a promising technique in comparison with hot air drying method for drying of green leaves with minimum degradation in chlorophyll. [ABSTRACT FROM AUTHOR]

• Several potential barriers to the implementation of solar drying technology in India are identified. • The DEMATEL scheme is utilized to prioritize the identified barriers. • The sensitivity analysis is performed to test the robustness of the proposed methodology. • Political instability is identified as the most significant barrier to the implementation of solar drying technology in India. • Several potential recommendations for the removal of these barriers are also suggested to ensure the contribution towards the achievement of UN sustainable development goals. In the present scenario, food security is one of the major concerns in the Indian context; engendered due to increased population and other associated anthropological activities. Despite high levels of food production, the current poor ranking of the country in the Global Hunger Index (GHI) has put an alarming trend for policy-makers as well as the contributors working towards food security improvement. The significant post-harvest losses in several durables and perishable food products affect society adversely. The use of solar dryers is one of the most efficient, cost-effective, and sustainable techniques for various food-processing and preservation applications; without any compromise with their morphological structure. Besides having the pre-eminent product quality along with several economic, environmental, and social impacts, the adoptability of solar dryers has not touched a benchmark; as per expectation due to various associated potential barriers. In this work, a systematic framework, utilizing the MCDM tools; has been suggested for the identification and prioritization of several barriers responsible for such a hampered adoption rate. The study comprises three major sections- (a) Identification and categorization of potential barriers, (b) Prioritization of identified barriers using DEMATEL scheme based priority weights, followed by (c) the sensitivity analysis to confirm the robustness of the proposed methodology. The findings suggested that political instability and interference have a significant impact on the adoptability of solar-thermal-based drying technology. Several potential recommendations for the removal of these barriers are also suggested to ensure the contribution towards the achievement of UN sustainable development goals. [ABSTRACT FROM AUTHOR]

An experiment was carried out in the laboratories of the Department of Food Engineering, Department of Vegetable Science, and Department of Plantation Spices Medicinal and Aromatic crops, Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal, India. The work was performed during 2018–2019 and 2019–2020 with different drying methods including sun drying, solar drying and oven drying. In oven drying, different temperatures such as 50, 55, 60, 65, and 70 °C were considered. A randomized complete block design (RCBD) was designed with seven treatments and three replications. Experimental results were significantly varied among the treatments as influenced by different drying methods and temperatures. Minimum time taken (480 min) to reach safe moisture content was recorded in T7 (oven drying at 70 °C), whereas maximum values in color components such as L* value (24.55), a* value (32.14), b* value (20.53), and pungency score (7.85) were recorded in T6 (oven drying at 65 °C). However, the highest texture (1180.81) was observed in T1 (sun drying). Biochemical parameters were significantly varied among the treatments. The maximum amounts of ascorbic acid (56.06 mg/100 g) and oleoresin content (10.72) were found in T3 (oven drying at 50 °C), whereas minimum values of biochemical parameters were recorded by T1 (sun drying) and T2 (solar drying) methods, respectively. Mathematical relationships were found in different drying methods and temperatures. Models such as the Lewis, Page, Modified Page, and Henderson and Pabis models were selected to fit the data. Maximum R2 value (0.9835) was found in both the Page and Modified Page models with similar values of drying method and temperature at 65 °C. This value was the highest among all models in all drying temperatures. However, the lowest χ2, and RMSE values (0.000818 and 0.027261, respectively) were recorded with the Page model. [ABSTRACT FROM AUTHOR]

Assessing the probability of failure of typically adopted cover depths to resist the onset of carbonation-induced corrosion under the influence of seasonal rains is important for the durability design of reinforced concrete elements. The exposure scenario commonly manifests in the tropics, wherein the majority of monsoonal rainfall remains confined to location-specific annual wet-spells. The study aimed to develop an improved methodology for the identification of annual wet-spell and proposed an index based on the judicious combination of wet-spell characteristics to enable the mapping of its severity over a region of interest and facilitate the selection of Moisture Reference Years (MRYs). The developed paradigm was implemented using gridded meteorological data sets to map the severity of annual wet-spell at 1° resolution for India. The map provides an improved severity classification compared to rainfall amount over regions of scanty rain but considerable wet-spell duration. The estimates of time conducive for carbonation over a period of 100 successive MRYs, as deduced from the simulated moisture distribution data for the five climatic zones of India, were also found to correlate well with the corresponding index values. Finally, the √t modeling of the carbonation depth using the derived estimates of conducive duration and assessment of failure probabilities of typical cover depths suggested that a nominal depth of 45 mm is able to resist carbonation at a safety level of 90% for all the five climatic zones. [ABSTRACT FROM AUTHOR]

Jaggery is a traditional Indian sweetener prepared from sugarcane juice through evaporation process and is considered as medicinal sugar due to its nutritional and thereupatic properties. To improve the shelf-life of solid jaggery, making jaggery in the form of granules with moisture content of 1-2% was recommended. A Polyhouse solar dryer for drying granular jaggery with a capacity of 200 kg was developed at Regional Agricultural Research Station, Anakapalle, Andhra Pradesh, India. Traditionally, granular jaggery was dried in openyard resulting in contamination with dust, insects, birds and rain. A comparative study was carried for drying granular jaggery with initial moisture of 9.3 to 10.5% (db) in both polyhouse solar dryer and in an open yard during the month of March-April, 2019. The study revealed that the rate of drying was faster in poly house compared to open yard drying. The temperature inside the polyhouse dryer was 59% higher than the ambient conditions. The percent saving in time for drying of granular jaggery in poly house dryer was 38% to attain optimum moisture content of 1.7% for stable shelf life besides maintaining hygienic conditions. The quality parameters of jaggery in terms of sucrose and reducing sugars percentage showed insignificant changes in both methods. However, the color of the granular jaggery was well retained in polyhouse dryer compared to open yard drying. Hence, this study will be helpful for small and micro entrepreneurs for large scale drying of granular jaggery under hygienic conditions utilizing renewable energy resources. [ABSTRACT FROM AUTHOR]

Low-temperature drying (withering) is the first stage in black tea processing. Determination of appropriate end moisture content of green tea leaf as well as temperature and relative humidity (RH) maintained during withering eventually aid the final quality of the processed tea. Therefore, the tea leaf withering (partial drying) properties were evaluated in an environmental chamber using mathematical models. The temperatures and RH considered were 25, 30, 35 °C and 80, 85, 90%, respectively. A total of nine combinations of temperature and RH were considered by keeping one parameter constant. The conditions were taken adhering to that of the climatic conditions of Assam, India. The withering data from experiments were fitted into five drying models using the curve fitting method. The Page model gave better predictions with an R² value of 0.9989 at 30 °C temperature and 90% RH. The total phenolic and flavonoid contents of the tea leaf samples were evaluated. The best results were 50.60 ± 0.02 mg GAE·g-1 (GAE - gallic acid equivalent) and 22.47 ± 0.01 mg QCE·g-1 (QCE - quercetin equivalent) at 30 °C withering temperature. [ABSTRACT FROM AUTHOR]

Different levels of ethyl oleate and potassium carbonate were tried to produce raisins by following DOV method. The application of ethyl oleate and potassium carbonate is found suitable for faster drying of grapes (Vitis virifera L.) in DOV method and able to produce quality raisins. However, application of solution (15 ml ethyl oleate and 25g potassium carbonate in 1L water) on first day and on 4th day (11 ml ethyl oleate and 18 g potassium carbonate in 1L water) was found most effective than other treatments. Further, studies on canopy management, load management and refinement of other agro-techniques are needed to obtain quality raisins by adopting DOV under tropical conditions of India. [ABSTRACT FROM AUTHOR]

High temperature and humidity of many reason of India in the summer season is the major challenge for human comfort also in the drying. In the present work, experiments have been performed to examine the cooling and dehumidification process in the summer season for human comfort and industrial application with the help of calcium chloride (CaCl2) based desiccant material solid desiccant wheel integrated with solar heating arrangements. In this study experimental findings are also evaluated by the mathematical model. During the dehumidification of air in the process unit humidity changes from 17.75 to 29.03 g H2O/kg dry air to 2.8–3.9, 6.8–8.15, 8.92–10.9 & 9.79–11.87 g H2O/kg dry air for flow rate at 1, 2, 3 & 4 m/s, respectively. The process air outlet temperature is increased in the range of 2.58–3.53 K for all air flow rates. After humidification of process outlet air, human comfort condition (HCC) is produced with temperature and humidity in the range of 30–33 °C and 7.77–12.47 g H2O/kg dry air for different air flow rates. Overall airflow for velocity 2–4 m/s can be recommended for the HCC condition. The proposed modelled expression indicates less than 10 % error between the actual and modelled value for different sections. [ABSTRACT FROM AUTHOR]

A natural circulation solar dryer has been evaluated for drying differently processed turmeric. The predrying treatments namely, hydrothermal treatment using water boiling and steam boiling; and drying methods namely, drying of sliced and unsliced turmeric rhizomes have been investigated. The open sun drying and untreated unsliced turmeric rhizome was used as control. The maximum thermal efficiency of this passive solar dryer has been obtained as 22.4% for the water boiled sliced turmeric, and while that for the steam boiled unsliced turmeric was 14.1%. The thermal efficiency was comparatively lower for untreated turmeric. The quality parameters namely, polishing loss, curcumin content, volatile oil content, total recovery, and color, were found better for steam boiled unsliced turmeric dried in solar dryer. Based on combined perspective of thermal efficiency and quality, drying of unsliced rhizome pretreated with steam in natural circulation solar dryer is recommended as compared to other processing practices. The dryer is economically feasible as indicated by the cumulative present worth of life cycle savings and payback period. Practical Applications: In India, turmeric is an essential part of cuisine. The drying operation consumes maximum time and energy in postharvest processing of turmeric. The conventional practice of drying is open sun. The aim of the article was to find the best drying method and pretreatment method for drying in a natural circulation solar dryer, which will also result in saving conventional energy. It was found that the drying in this solar dryer results in lesser drying time and better quality as compared to conventional method of open sun drying. [ABSTRACT FROM AUTHOR]

In India, groundnut is mainly used for oil extraction or consumed in roasted form prompting a need for diversification to further increase its value and utility. In the present study, spray drying of groundnut milk was carried out using three variables of spray dryer i.e., inlet air temperature (180–220 °C), atomization air pressure (2–3 bar), feed pump speed (24–36 rpm) using Box-Behnken design of Response Surface methodology. The moisture content of powder decreased with an increase in inlet air temperature and atomization air pressure. The bulk density increased with increase in atomization air pressure. Maximum dispersibility (98.48%) was observed at an atomization air pressure of 2.57 bar. The insolubility index of the powder increased and lightness value (L*) decreased with an increase in inlet air temperature. The optimized conditions for spray drying of groundnut milk were inlet air temperature: 186 °C, atomizing air pressure: 2.5 bar and feed pump speed: 27 rpm. Unlabelled Image • Optimized level of spray drying parameters. • Spray dried groundnut milk powder with good sensory acceptability. • Relationship of spray drying parameters with quality of groundnut milk powder. [ABSTRACT FROM AUTHOR]

Magnesium metal is used in automobile, sports and aircraft industries. It is also used in aluminum alloys and titanium production. The main raw material for magnesium production is anhydrous magnesium chloride which can be produced from sea water bitterns, magnesite and dolomite. Sea water bitterns from Bhavanagar, Gujarat, India has been used to produce magnesium chloride in the present study using low temperature spray drying. As bitterns solution contains lot of sodium and sulfate, efforts have been made to remove both these elements before spray drying. The purified solution is subjected for spray drying and the variables covered during spray drying are feed flow rate, inlet temperature and atomization pressure. With increase in flow rate from 2 to 5 mL/min, % of magnesium chloride content in the product is reduced from 57.58 to 52.73 %. Temperature and atomization pressure are not having significant effect on percentage of magnesium chloride in the product. The spray dried powder contains moisture content which is removed by thermal decomposition. Thermal drying studies such as temperature, duration of thermal drying have been carried out. The final product of MgCl21.31H2O is suitable for magnesium metal production using fused salt electrolysis. [ABSTRACT FROM AUTHOR]

Jackfruit (Artocarpus heterophyllus) production is abundant during the summer season in Southeast Asia and is also produced throughout the year in some parts of South India. Attributed to the absence of viable process technology, the pulp is predominantly consumed fresh and has not been used effectively for other applications such as in ice cream, beverages, custard preparations, or as a flavor enhancer. The conversion of the high sugar‐containing pulp to powder is difficult. Hence, the foam‐mat drying of jackfruit pulp was carried out using different foaming agents and stabilizers. The effect of maltodextrin (MD; 3%, 4%, and 5% w/w), glycerol‐monostearate (GMS; 2%, 3%, and 4% w/w), or soy protein (SP; 0.5%, 1%, and 1.5% w/w), and 0.5% methylcellulose added to the pulp at a concentration of 8 °Brix on foam expansion (FE; %), foam retention (FR; %), total carotenoids (TC; mg/100 g pulp), and overall acceptability (OA) were investigated, and their levels were optimized using central composite design of response surface methodology. The foam mats were dried at a drying air temperature of 70°C along with a foam thickness of 4 mm. The samples were evaluated based on drying time, foaming, functional, biochemical, and sensory qualities. The optimum levels of MD and GMS were 3.96% (4.0%) and 3.01% (3.0%), respectively, which led to the foam‐mat‐dried jackfruit powder with properties within the desirable range. At these optimum conditions, the predicted FE, FR, TC, and OA were 69.84%, 89.42%, 0.152 mg/100 g pulp, and 7.73, respectively. The optimum levels of MD and SP were 3.95% (4.0%) and 1.02% (1.0%), respectively, and the corresponding properties (considered as responses) of this foam‐mat‐dried jackfruit powder such as FE, FR, TC, and OA were 74.45%, 84.80%, 0.14 mg/100 g pulp, and 7.6, respectively. Practical Application: This study is one of the few studies that is focused on the development of a technique for the long‐term preservation of jackfruit powder for further applications that will also reduce the wastage of jackfruit attributed to its fast perishability. This technology can be replicated in other parts of the world. This article has demonstrated foam‐mat drying as a useful technique to achieve high‐quality jackfruit pulp powders with desirable drying, foaming, functional, biochemical, and sensory qualities using different foaming agents and stabilizers. [ABSTRACT FROM AUTHOR]

• Purpose of ETC aided hybrid solar dryer is to provide prominent heat. • The designed dryer is easy to operate and is found to be eco - friendly. • Drying kinetics of cassava is determined using IBM SPSS 23 statistical package. • Proximate analysis reveals that ETC dried cassava is better than sun dried cassava. A prototype hybrid Photovoltaic Thermal (PV – T) solar dryer aided with Evacuated Tube Collector (ETC) is presented for drying of cassava slices under the meteorological conditions of Thanjavur, Tamilnadu, India. Further the morphological, structural and physical properties of thin layer drying kinetics are studied and compared with natural sun drying. The designed dryer reduces the moisture content of cassava from 91.5% (wb) to 10.67% (wb) which is considered to be a safe level for storage in 8 h. There is a wide scope to save the conventional fuel by adopting the designed solar dryer as the air temperature inside the chamber rise is 30–40 °C than the ambient temperature. Non – linear regression analysis is performed to find out the drying kinetics of cassava using IBM SPSS 23 statistical package. Two - term model is proved to be the most suitable model for predicting thin-layer drying behaviour of cassava slices with R2 = 0.982, χ2 = 0.017553 for hybrid dryer and R2 = 0.998, χ2 = 0.001247 for open sun drying. XRD results exhibit 'A' type crystalline pattern that indicates semi–crystalline nature of cassava for both hybrid and sun dried cassava. Structural, morphological and proximate composition analysis reveals that the quality of hybrid dried cassava is better in terms of physical and chemical compositions than sun dried cassava. The proposed hybrid dryer is capable of producing high standard dried products for exporting and can make a good profit. [ABSTRACT FROM AUTHOR]

Betel leaf or "Paan" is contemplated as "a neglected green gold of India" due to its nutritional, economic, medicinal, social and cultural values. However, surplus production of the leaves during the glut season and lack of adequate storage facilities compels the betel leaf growers to sell it at a throw away price. Therefore, to overcome this problem, the preservation techniques like shade drying, hot air oven drying and vacuum oven drying have been widely used, but these methods produce lower quality dried betel leaves or consume more time to dry. Freeze drying is a well-known technique to dehydrate heat sensitive products without damaging its actual quality. Hence, the current study was taken up to compare quality of freeze-dried betel leaves with shade dried, hot air oven dried and vacuum dried betel leaves. Drying conditions for shade drying, hot air oven drying, vacuum drying and freeze drying were 32 ± 3°C, 60°C, 60°C and 0.5atm, and - 40°C and 0.21 atm, respectively. Eight different thin layer drying models were studied and compared based on coefficient of determination (R2), root mean square error (RMSE) and chi square. A sensory study on dried leaves was also conducted on 9-point hedonic scale. The results showed that Page model was the best fitted model for freeze drying (R2 = 0.992) and vacuum drying (R2 = 0.995) methods, whereas Peleg model and Verma et al. model were found to be best fitted for shade drying (R2 = 0.997) and oven drying (R2 = 0.993) methods, respectively. The results also revealed that both freeze dried and shade dried contained the highest essential oil content (1.5%) compared to oven dried (1.0%) and vacuum dried (0.8%) betel leaves. However, shade dried leaves were found to be the most preferable by the panelists during organoleptic evaluation followed by freeze drying, hot air oven drying and vacuum drying. Therefore, it can be stated that freeze dried leaves are analogous to shade dried leaves in terms of quality. However, freeze drying took much lesser time (10h) to dry compared to shade drying (10 days). Hence, freeze drying can be considered as a suitable preservation technique for drying of betel leaves. [ABSTRACT FROM AUTHOR]

Dry flower market has grown exponentially as consumers become eco-conscious and choose dry flowers as eco-friendly and biodegradable alternative to fresh flowers. Dried flowers and other plant parts are nature's everlasting gift which can be treasured over years. They have tremendous potential as substitute for fresh flowers and foliage as their charm can be maintained from few months to years with lesser cost. The market demand of dry flowers and ornamentals is increasing day by day and can become lucrative income generating hobby for entrepreneurs in India either by producing or marketing dried flowers and ornamentals. [ABSTRACT FROM AUTHOR]

A declining trend in Indian summer monsoon precipitation (ISMP) in the latter half of the 20th century is a scientifically challenging and societally relevant research issue. Heavy aerosol loading over India is one of the key factors in modulating the ISMP. Using the state-of-the-state-of-the-art chemistry-climate model, ECHAM6-HAMMOZ, the impacts of South Asian anthropogenic sulfate aerosols on the Indian summer monsoon precipitation were investigated against: (1) 2010 La Niña (excess monsoon), (2) 2015 El Niño (deficit monsoon) in comparison to (3) normal monsoon 2016. Sensitivity simulations were designed with 48% enhancement in South Asian SO 2 emissions based on a trend estimated from Ozone Monitoring Instrument (OMI) satellite observations during 2006–2017. The model simulations showed that sulfate aerosols reduce ISMP by 27.5%–43.3 %, while simulations without sulfate loading enhanced ISMP by 23% in 2010 La Niña and reduction by 35% in 2015 El Niño. This paper reports that sulfate aerosols loading over India reduce precipitation by aerosol-induced direct and indirect effects by inducing atmospheric cooling, weakening in the convection, and reduction in moisture transport to Indian landmass. This paper emphasizes the necessity of alternate use of energy to reduce sulfate aerosol emissions to solve water issues in South Asia. [Display omitted] • Sulfate emission reduces Indian summer monsoon precipitation through aerosol-radiation and aerosol-cloud interactions. • Over 27% of the summer monsoon rainfall deficit in a normal year are linked to Asian anthropogenic sulfate emissions. • Sulfate-induced rainfall reduction is the maximum for La Niña year. • SO 2 loading increases atmospheric stability and weakens moisture transport to India. [ABSTRACT FROM AUTHOR]

Background: Rice is the major crop in India in terms of area, production and consumption. Rice occupies about 23% of the gross cropped area and 35% of the total area under food grains in the country. Rice is of one key importance to the economy as well as a staple food for Telangana people, requiring about 50 lakh tons annually to feed the state population. In recent times the area under rice cultivation has been increased and is expected to hit the one crore acre mark by rabi season 2022. In any type of crop production system an accountability of inputs, energy spent, yield and costs must be monitored, by that one can modify it or substitute it for obtaining the better results. Methods: Due to decline in the share of agriculture workers in the country, there is a need to adopt new technologies in rice cultivation. Dry direct seeding of rice refers to direct sowing of rice seeds in the dry field rather than by transplanting seedlings from the nursery. A study was conducted to compute the inputs and energy consumptions in manual transplanted rice production (MTR) and dry direct seeding rice production (DDSR) methods of paddy cultivation in the combined Nalgonda district of Telangana State, during 2020-21. Firstly, the different operations performed in these two methods were listed out, then by using suitable energy equivalents total energy consumed in two methods of operations were calculated. Result: The human energy spent in the manual transplanted rice production and dry direct seeded rice productions were 506 and 92.84 MJ/ha respectively. Specific energy noted for dry direct seeded rice production and manual transplanted rice productions were 2.10 and 2.28 MJ/kg respectively. A total saving of Rs. 16,000/-ha-1 was recorded by practicing the dry direct seeded rice production method over the manual transplanted rice production method. On comparing both the methods for overall energy consumption, manual energy consumption and cost of cultivation DDSR method was found to be more efficient than MTR method in the district. [ABSTRACT FROM AUTHOR]

In the absence of effective drying techniques, a lot of food gets wasted as there is a lack of post-harvest processes. In India, most of the agricultural produces like paddy, maize, wheat, corn, oil seeds, pulses, chillies, etc. require a temperature range of 50–80 °C for effective drying. Hence, in these conditions, solar drying techniques seem to be the most economical; also, it is safe and eco-friendly. Various types of solar dryers are used across India and worldwide; these are direct solar dryer, green house dryer and indirect solar dryer. Nowadays, indirect type solar dryers are most commonly used because of their several advantages over direct solar dryers. In case of indirect type solar dryers, the products to be dried are kept inside a separate compartment known as drying chamber. Hot air is obtained from the solar collectors either by direct heating method or by using a secondary heating medium and then supplied to the drying chamber for heating of the products. This paper presents a detailed review of various innovative designs of indirect type solar dryers and compares the performance of different types of dryer configuration in terms of collector efficiency, dryer efficiency, drying time and maximum air temperature. Also, the effects of various operating parameters on the thermal performance of such dryers have been discussed. [ABSTRACT FROM AUTHOR]

Lemongrass (Cymbopogon citratus) is an aromatic, medicinal oil-bearing grass that grows spontaneously in tropical regions like Malaysia and India. The effects of drying periods (fresh sample, 1 day, 2 days, and 3 days of drying) on essential oil yield and chemical composition of C. citratus was investigated. The chemical composition of the oils was analyzed using gas chromatography flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC/MS). The post-harvest drying periods were found to be beneficial for improving oil yield of C. citratus. The highest essential oil concentration (0.392% v/w) was obtained from samples dried for 2 days post-harvest compared to 1 day (0.28%) and 3 days (0.31%) post-harvest periods. The major components were α-citral and β-citral followed by myrcene for both fresh and dried samples. Drying periods had no significant effect on the main components of the lemongrass essential oil. Nevertheless, the post-harvest drying periods had a marked effect on the proportions of monoterpenes. [ABSTRACT FROM AUTHOR]

Betel leaf is the green gold of India for its food and medicinal values. In India, betel leaf is cultivated around 55,000 hectors of land encompassing about 20 lakhs Boroj and employing same number of agricultural families. But due to its perishability and short shelf life, 35-70% wastage takes place every year due to storage and transport, logistics. So, drying can be an effective tool to preserve the betel leaf for a long time period. Therefore, the aim of the study was to optimize the drying time as a function of leaf surface area and drying temperature as well as determine the changes in drying characteristics for changes in drying temperature and leaf surface areas. Piper betel leaf cultivated in Midnapore district, West Bengal, India, was considered as raw material for the study. The experiments were conducted at three range of temperature and leaf surface area. Temperature and leaf surface area both have a significant effect on drying rate and in decrement of total drying time (p<0.05). With increase in surface area of exposure and drying temperature the moisture diffusivity initially increases but later on decreases. Three drying mathematical models were applied and one response surface model was developed in this study. Wang & Singh model and response surface model both were found to be best (p<0.05) for describing the drying kinetics. [ABSTRACT FROM AUTHOR]

Melaleuca linariifolia Sm. (Genus: Melaleuca ; Family: Myrtaceae) cultivated for its ornamental usages in the Kumaun Himalayan region of Uttarakhand is commercially known as flax-leaved paper bark tree. The present study analyzes the chemical variation of the essential oils obtained from aerial parts and flowers of M. linariifolia. The effect of post-harvest shade drying on the essential oil composition was also assessed in the study. Total of 16 compounds accounting for 94.2 % and 94.6 % were identified in the aerial parts and flowers essential oil, respectively. 1,8-Cineole (71.8 %–73.8 %) was identified as the predominant compound in both the studied essential oils followed by limonene (1.7 %–9.3 %) and α-terpineol (4.2 %–6.7 %). Moreover, the fresh aerial parts had 73.8% of 1,8-cineole content which increased up to 79.2% post-harvest drying. The study revealed oxygenated monoterpenes as the major class constituents with 1,8-cineole as the marker component ranging from 67.7 % to 79.2 % during the post drying analysis. While assessing the biological activities, the antioxidant activity of the oils was investigated in vitro using three assays: DPPH radical scavenging activity, Iron(II) complexing activity, and H 2 O 2 radical scavenging activity. The oil also inhibited the activity of α-amylase with IC 50 of 3.26 ± 0.04 μg/ml and protein denaturation with IC 50 of 3.0 ± 0.03 g/ml. This is the first-time report of essential oil analysis of M. linariifolia flowers and post-harvest drying study from bhabar region of the Kumaun Himalayas. The high essential oil yield, rich chemical composition and biological activities suggest the cultivation of Melaleuca species as an industrial crop. [Display omitted] • The flowers of Melaleuca linariifolia show high essential oil yield than aerial part (leaves + stem) of the plant. • Chemical composition of essential oil of Melaleuca linariifolia was analyzed by using GC-FID and GC-MS techniques. • Post harvest shade drying results increase in percentage concentration of marker compound 1,8-cineole upto 79.2%. • Biological activity analysis confirms potent in-vitro antioxidant, inhibition of α-amylase, and inhibition of protein denaturation activities in essential oil. • This study provides a directive for development of high yielding and commercially benign species of Melaleuca linariifolia. [ABSTRACT FROM AUTHOR]

Tamarind is widely consumed as fruit and spices in India. Tamarind contains pulp, seeds, shell and fibres. The pulp, which makes up between 30 and 50% of the mature fruit, is rich in reducing sugars, pectin, protein, fiber, and cellulose substances. Study of various physical engineering properties such as moisture content, fruit size, length, width, thickness, and weight (pulp, seed, shell, etc.) is important for designing the post-harvest machineries of tamarind. Major unit operations for processing of tamarind includes drying, dehulling, deseeding, pressing and storage. Traditional and mechanical approaches are used for these operations. Mechanical approaches of tamarind processing are carried out by dehuller and deseeder machinery. One of the crucial unit procedures in the processing of tamarind is deseeding which can be done by deseeder, mechanically. Processing of raw tamarind into value-added goods may increase its worth in addition to increase in shelf life. Additionally, it boosts the income of producers and processors. Value added products of tamarind are pulp, tamarind juice concentrate, tamarind pulp powder, tamarind pickle, tamarind jam, tamarind syrup, tamarind candy, tamarind kernel powder, dried fruit block, tamarind chutney and beverages. Tamarind is also rich in major amino acids phytochemicals and hence it carries the properties of antidiabetic, antibacterial, antivenomic, antioxidant. This paper provides an overview of the engineering properties, processing technologies, value added products, technologies and machineries developed/available for tamarind and its health benefits which will further help in machinery, protocol, technology and product design and development. [ABSTRACT FROM AUTHOR]

Persimmon (Diospyros kaki) is an important, underutilized fruit crop of India. The thin layer drying of persimmon slices would make it a perfect snack that can be used in various recipes. The drying process of persimmon slices was optimized using Box–Behnken design in response surface methodology. Three categorical independent drying variables, such as temperature (50–70°C), air velocity (0.5–1.5 m/s), and sample thickness (4–8 mm), were considered for the study. The response variables include drying time, ascorbic acid content, browning index, and rehydration ratio were investigated. The air temperature and sample thickness showed a significant effect on drying time. Browning index and rehydration ratio were significantly affected by air temperature and air velocity. As per the given experimental design constraints, the optimum solutions obtained were air temperature (58°C), air velocity (1.40 m/s), and slice thickness (4 mm). The predicted responses for the optimized combination of the drying process were drying time (442.55 min), ascorbic acid (8.61 mg/g dry matter), browning index (0.396 absorbance unit), and rehydration ratio (5.47%). Therefore, this study would be beneficial for scaling up industrial drying of persimmon slices for commercial production to ensure smooth processing and achieve a profitable path. [ABSTRACT FROM AUTHOR]

• 6 kg/batch mixed-mode solar thermal dryer designed and developed for drying of natural rubber sheets. • Natural rubber sheets in the dryer dried in 3 days compared to 7–8 days in conventional way. • Two drying models derived: one based on dimensionless value (τ) and other on time (t) value. • Average energy and exergy efficiencies were 9.09% and 2.48% respectively. • The dryer dried sheets were superior to the open sun dried ones in terms of colour and other physical properties. • Techno-economic analysis showed a payback period of 2.2 y. In the north-eastern geographical setting of India, lies Tripura, the second largest state of India in terms of natural rubber cultivation. Often, the unpredictable weather and lack of appropriate drying methodology deteriorates the quality of the dried natural rubber fetching less income to the unorganized small scale farmers. Installation of modular solar thermal dryers in this region can resolve this problem. In this study, a 6 kg/batch mixed-mode solar thermal dryer was developed and installed at Agartala for performance investigation. Moisture content of the natural rubber sheets dried in the solar thermal dryer was reduced from 40% to 4% vis-à-vis 11% in open sun drying condition in 3 days' time on wet basis. Six drying models were studied and validated against the experimental data. The average energy and exergy efficiencies of the system for natural rubber sheet drying were 9.09% and 2.48% respectively. Quality of the solar dryer dried sheets were found to be superior to the open sun dried ones. Techno-economic analysis showed a payback period of 2.2 y. Innovative features of the developed solar thermal dryer include (a) recirculation of spent dehumidified air to minimize thermal energy loss (b) 90% UV cutoff in the drying chamber leading to better colour retention of the product (c) solar photovoltaic operated dehumidifier for use during night to prevent reabsorption of moisture. The higher throughput, better quality and ease of operation can make this mode of natural rubber sheet drying an attractive option among akin communities. [ABSTRACT FROM AUTHOR]

Mango leather produced from dried mango pulp is a traditional fruit product in India. Traditionally it is processed through natural convective drying or sun drying of ripe mango pulp. Mango leather was produced through sun, convective (hot air), freeze, and microwave drying. Drying kinetics was studied with the help of nine empirical models used extensively in food industries. Root mean square error (RMSE), correlation coefficient (R²), and the sum of square errors (SSE) these four statistical measures were examined for nine different models to learn the best-fitted model. The Fourier-transform infrared spectroscopy study was conducted for compositional analysis of differently dried samples in the wavelength range of 400-4000 cm-1 at ambient temperature. For sensory analysis, the test panel was constructed as per ISO 8586-1. ISO 4120:2004, ISO 5496:2005, ISO 10399:2004 standards were maintained for selecting panel members. Quantitative descriptive analysis of different mango leather was estimated as per the protocols defined in ISO 11035:1994. [ABSTRACT FROM AUTHOR]

The present study aims at establishing the resourcefulness of a low-temperature/low-humidity dryer, namely, Refrigeration Adsorption Dehumidified Dryer (RADD) for the drying of carrots, vis-à-vis a fluidized bed dryer (FBD). Notably the RADD is a customized design developed by the Agro-Processing and Technology Division of CSIR-NIIST, India. The differently dried carrot samples were compared for the drying rate, rehydration ratio, shrinkage kinetics and physicochemical quality characteristics such as moisture content, morphology, color and sensory attributes. The moisture content of carrot was reduced from an initial value of 80 g moisture/100 g of sample to 10 g moisture/100 g of sample (wet basis). Though the drying rate was higher in FBD than RADD, the percentage removal of moisture content was higher in the latter due to the synergistic effect of heating and dehumidification of drying air. Similarly, rehydration of RADD-dried carrots was slower (4 h) than their FBD counterparts (3 h). But, within the aforementioned duration, RADD-dried carrots achieved ∼96% of rehydration weight attained by the FBD-dried carrots. The total phenolic and flavonoid contents and amount of β-carotene retained in dried carrot samples were higher after RADD. The color parameters of dried samples were not significantly different between the two drying techniques. [Display omitted] • Performance comparison of Refrigerated Adsorption Dehumidified Drying (RADD) and Fluid Bed Drying (FBD) is done. • Retention of bioactive compounds is high in RADD. • Rehydration ratio and Drying rate is high in FBD. • Colour and Textural attributes are better in RADD. • RADD is found to be an interesting alternative for FBD for drying agro produces and heat sensitive materials. [ABSTRACT FROM AUTHOR]

Open sun Crops drying is common in India even though a considerable time and dust accumulated. This is a serious issue. Workman ship and time reduction is needed to increase the productivity. Introduction of Green house solar dryer should be a right choice as against the conventional drying. The novel research focuses for retaining the nutritional values at higher level, very clean and with very less time for drying and supports the farmers at very affordable cost of drying. The four dryers are fabricated with two different roof materials and shapes. Each dryer bottom surface it is staked with three layers namely, black painted plywood, black PVC sheet of 3 mm thickness and stainless steel wire mesh tray. The results were noticed that moisture in the green peas is reduced from 76% to almost 9% in all dryers. The parabolic poly ethylene greenhouse solar dryer took 20 solar hr., whereas OSD took 32 solar hrs, in turns the saving of drying time is 37.5% compared to OSD. Different thin layer models were studied to fit with experimental data. Among all the thin layer models, Midilli and Kucuk model with PPEGHSD had shown a better agreement than the other models for the green peas. The performance and nutrition analysis have been carried out to ensure the quality of the dried products. It is observed that all the nutrition element values in the PPEGHSD are higher than the all other dryers and is suggested for the successful food grains drying. [ABSTRACT FROM AUTHOR]

An attempt has been made for drying of Bauhinia variegata flowers along with retaining its quality attributes. The effect of various pre‐treatments namely, steam blanching (0–6 min), potassium metabisulfite (KMS) (0–3,000 ppm), citric acid (0%–1%), and dipping time (0–45 min) was evaluated on physico‐chemical as well as phytochemical potential of dried B. variegata flowers. The optimized conditions (blanching time 1.20 min, KMS 1,031 ppm, citric acid 0.35%, and dipping time 18.72 min) for the pre‐treatment of B. variegata flowers resulted in desirable retention of the quality attributes (moisture: 14.34%, ash: 3.50%, phenolic: 407.67 mg/100 g, ascorbic acid: 66.38 mg/100 g, protein: 24.18 mg/100 g, tannins: 301 mg/100 g, antioxidant activity: 87.40%, flavonoids: 280.73 mg/100 g, and overall acceptability: 7.57). Cluster analysis revealed that all variables have significant and equal effect on the quality attributes of dried B. variegata flowers. Analysis through FTIR and HPLC counter confirmed the significant effect of the variables. Novelty impact statement: The Kachnar (Bauhinia variegata) is not only distributed throughout the India but has its roots throughout the world. It has gained popularity as a medicinal tree traditionally and is being utilized for curing different diseases. Despite of its composition and various health benefits, its commercial utilization is limited because of its availability at limited places for limited time. At various locations, the optimised conditions will aid in obtaining the joy of this nutritive flower for a much longer period of time. [ABSTRACT FROM AUTHOR]

In present communication, a solar dryer having semi-transparent photovoltaic thermal (SPVT) roof has been used to dry bitter gourd. Experimentation has been done and results were validated with linear regression method through mathematical modelling as well as for non-linear Artificial Neural Network (ANN) modelling has been used. The experimental data namely, ambient air temperature, moisture evaporated, bitter gourd surface temperatures, solar intensity on different surfaces of dryer, room temperature and relative humidity have been recorded for the climatic condition of Varanasi, UP, India. The numerical value of convective heat transfer coefficients for bitter gourd found to be between 0.69–14.45 W/m2 K. The results for mass transfer (moisture evaporated) during drying of bitter gourd from theoretical model (linear regression method and ANN) and experiments showed good agreement. Further, net electrical energy, thermal energy and overall thermal energy were found to be 0.62, 3.77 and 5.41 kWh/m2/day respectively. The payback period at 10% interest rate and 4% inflation rate with ₹ 50 ($0.77) and ₹ 100 ($1.54) saving rate per kg were found to be 1.47 and 0.72 years respectively. [ABSTRACT FROM AUTHOR]

Vegetable preservation through drying technology is an effective method to minimize wastage while satisfying the essential nutrition requirements. It is necessary to expand the existing technologies to preserve seasonal and regional specific vegetables. The present study is intended to find suitable conditions to increase preservation capacity through solar drying. A single slope solar dryer (SSSD) is designed, fabricated and ivy gourd is taken as a vegetable sample. Experiments are carried out in the highest temperature region in South India at 10.925°N latitude, 79.838°E longitude. The safe moisture content of the passive and active mode solar dryer was attained in 9 and 7 hr whereas it took 11 hr in sun drying. During the dehydrating process, the temperature of the system varied from 35 to 71°C. Existing kinetics models are used to optimize the "goodness of fit" and proposed a novel model to suit India's environmental conditions. Exergy analysis and thin layer drying kinetic studies are performed and studied the influence of various parameters in the dehydrating of ivy gourd. The study revealed that the air temperature, RH, global radiation, and airspeed, significantly influence the drying kinetics. However, all the above four drying parameters are interconnected to enhance the drying process and which in turn enhance the drying kinetics process. Obtained results are explained with suitable discussions. Practical Application: Almost 40–50% amount of food items annually are rotten all over the global due to deficiency of proper preservation methods. Solar drying is found as a sustainable approach for food preservation; however, the food items dehydrated under sun dehydrating lose their nutritional, medicinal properties due to slow and nonuniform dehydrating rate. In this article, the newly designed SSSD is developed and a thin‐layer dehydrating mathematical correlation for freshly harvested ivy gourd is conducted. The results showed that forced convection solar drying setup could enhance the product quality of ivy gourd and also decrease the dehydrating time. [ABSTRACT FROM AUTHOR]

The present study was conducted at College of Agricultural Engineering, Bapatla, Andhra Pradesh, India during the month of January, 2021 to develop photovoltaic power assisted forced circulation solar greenhouse dryer and to evaluate its performance for drying of paddy. A free standing greenhouse structure with arch roof was selected to have high light transmission and low cost of construction. To get adequate and uniform light inside the greenhouse east-west orientation was selected. A frame of solar greenhouse dryer having 4.467 m length, 2.134 m width and 2.591 m height was constructed and was covered with twin wall polycarbonate sheet of 6 mm thickness. Freshly harvested paddy was filled in perforated tray with size 142.5×80×12.5 cm up to 10 cm height the trays were placed in drying chamber consists of three tires and two columns. Forced ventilation was provided with four 40 W DC fans which were powered with two 150 W photovoltaic panels. During drying, the green house and ambient air temperature, relative humidity data was collected at every 1 h interval using data logger, the moisture content of the paddy was determined at every 2 h interval. The paddy was dried till getting 12% (w.b.) final moisture content. The highest greenhouse dryer temperature of 48.1°C was recorded as compared with highest ambient temperature of 34.2°C. Moreover, the air flow rate achieved was varied between 75.52‒34.25 m³m-1. In this dryer the paddy was dried from 25.3‒12.0% (w.b.) moisture content in 21 h whereas open sun drying took 28 h of drying time. [ABSTRACT FROM AUTHOR]