Reduction Of Post-harvest Losses Research Articles

Effect of Asparagus Chitosan-Rutin Coating on Losses and Waste Reduction During Storage

Abstract Storage is a crucial component of a sustainable and efficient food supply system. Reduction of postharvest losses and waste is a vital strategy to improve efficiency, ensure product availability, and reduce environmental impact. Asparagus (Asparagus officinalis L.) boasts a high nutritional value and complex of phytonutrients. Yet, the storage period for fresh asparagus is quite short, leading to rapid quality deterioration. An effective method to extend storage periods involves postharvest treatments using the natural biopolymer chitosan. The aim of the research was to assess the effectiveness of applying sustainable postharvest treatments based on chitosan and rutin, with a focus on losses and waste reduction during asparagus storage. The impact of the applied storage technology on the visual appeal and sensory attributes of asparagus, along with its effects on respiratory metabolism, weight loss, soluble solids, soluble carbohydrates, chlorophylls, and carotenoids, was systematically assessed. The findings indicate that the post-harvest treatment using chitosan and rutin effectively preserves the visual characteristics of asparaguswhen the storage period is prolonged to a week. A major advantage of this technology is a substantial reduction in waste, achieving the levels of 1.0-1.5%. The proportion of standard products post-storage ranged from 94.4% to 96.0%. The treatment with chitosan and rutin efficiently reduces weight loss by half and suppresses the respiration rate, leading to decreased losses in soluble solids, carbohydrates, chlorophylls, and carotenoids during storage. These outcomes underscore the effectiveness of the applied coating in impeding metabolic processes, resulting in minimized quantitative and qualitative losses in the product quality during a prolonged storage.

A Scoping Review of Postharvest Losses, Supply Chain Management, and Technology: Implications for Produce Quality in Developing Countries

Highlights A scoping review of 385 articles containing relevant literature, research studies, and connections among postharvest losses, produce quality, supply chain management, and technology use was performed. Several postharvest factors, including handling, pre-cooling, washing and sanitation, sorting and grading, packaging, storage, and transport, play key roles in maintaining produce quality, but stakeholders in developing countries or emerging economies often lack access, infrastructure, equipment, and capital, resulting in significant losses. Supply chain management plays an important role in reducing postharvest losses, yet managerial, socioeconomic, and supply hindrances create impediments to fresh food industries in developing countries. Recently developed technologies in cold storage, artificial intelligence, and tracking and tracing can have a significant impact on produce quality, and while developing countries have adopted new technologies rapidly, there are still financial, social, and regulatory obstacles limiting uptake. Abstract. Rising global population and increased demand for fresh food, especially in developing countries, underscore the critical need to address postharvest losses to ensure food security. Effective postharvest practices, supply chain management, and technology are key factors to sustaining produce quality. However, the magnitude and nature of these factors vary between developed and developing countries. Developed countries tend to have more efficient supply chain management systems, a highly skilled workforce, and greater access to advanced technologies, leading to a higher level of produce quality and fewer postharvest losses. In contrast, developing countries often suffer from inadequate infrastructure, a lack of access to modern technologies, a lack of skills to properly grade, sort, package, transport, and store produce, as well as poor quality control. Addressing these issues through improved supply chain management, the adoption of appropriate technologies, and training and education could lead to a reduction in postharvest losses, produce quality that is maintained, and a safer, more secure food supply. This article presents a scoping review of literature on postharvest factors, technologies, and practices resulting in the deterioration and losses of fruits and vegetables in fresh food supply chains, with an emphasis on developing countries. Existing and emerging technologies and supply chain management practices that maintain quality and facilitate the delivery of high-quality produce were highlighted. First, a conceptual framework for supply chains is presented to guide discussion on technical, economic, and policy opportunities and to provide insights that may strengthen the resilience of food systems in developing countries. Next, techniques and practices used in the produce industry were summarized, including how effective supply chain management can maintain quality and reduce postharvest losses at key distribution stages. Finally, recent literature on technology, applications, and barriers to adoption is presented, and strategies to strengthen supply chain resilience in developing countries are discussed. Keywords: Developing countries, Food loss, Food security, Postharvest losses, Postharvest management, Produce quality, Smallholder farmers, Supply chain management, Technology adoption.

Colour, nutritional composition and antioxidant properties of dehydrated carrot (Daucus carota var. sativus) using solar drying techniques and pretreatments

Carrot is a seasonal perishable tuberous root vegetable which presents a preservation challenge owing to its elevated moisture content. Recently, carrot processing has received more attention because of its many health-promoting qualities and the reduction of postharvest losses in a cost-effective safe way. This study was designed to sort out the effective solar drying technique including pre-treatment that would retain the color and quality characteristics of dehydrated carrot. Carrot slices were subjected to dry using open sun drying (D1), solar drying long chimney (D2), solar drying short chimney (D3) and box solar drying (D4) techniques with the pretreatments of ascorbic acid 1 % (C3), citric acid 5 % (C4), potassium metabisulfite 1 % (C5) and potassium sodium tartrate 0.3 % (C6) before drying. Drying characteristics, nutritional attributes, phytochemicals and antioxidant of the dehydrated carrot samples were compared with the fresh sample and untreated (control) sample. Results showed that D4 was a good drying method to preserve nutritional quality with good appearance. Among the pretreatments, C5 and C4 resulted improved nutritional quality retention, enhanced visual acceptability and enriched antioxidant activities. PCA (Principal Component Analysis) and correlation matrix revealed that D4 with C5 retained the maximum amount of vitamin, minerals, total phenolic content, antioxidant and admirable dehydrated carrot color by inactivating enzymatic reaction. Therefore, box solar drying with potassium metabisulfite pretreatment would be very promising for functional carrot drying retaining acceptable color and nutrition composition.

Use of a forced convection solar dryer for the reduction of post-harvest losses: case of the ‘akikon’ tomato variety in benin (West Africa)

The local variety tomato (Lycopercicum esculentum Mill) named ‘akikon’ is one of the most consumed and widely cultivated fruiting vegetables in Benin Republic. In this work, we designed and built a dryer usable for limiting the frequent losses of the massive produced tomatoes. This paper analyzes the first results, obtained from the different experiments carried out with the developed dryer, in a context of forced convection. The results showed that increasing the temperature from 55 to 70 °C resulted in a shorter drying time decreasing from 1266 to 672 min with a brighter colour of the dried tomatoes for 70 °C. However, the increase of temperature does not affect the smell of the dried tomatoes. After drying, 7 to 8 months were required before we notice a colour change (from red to red-brown) of the dried product , indicating that the storage method still needs to be improved.

Why cassava processors will patronize mechanized cassava peeling machine service

Cassava peeling machines are available but are inaccessible and prohibitively expensive, especially for small-scale processors to acquire. This paper examines the perception and willingness of smallholder cassava processors to pay for cassava peeling machine services using data from 300 cassava processors in the Bono East Region of Ghana. A perception index from a 5-point Likert Scale and Cragg’s Double Hurdle model were the methods of analysis. The results revealed a perception index of 2.54 and this implies that cassava processors have neutral perception about the cassava peeling machine service. Also, it was found that majority of the processors (75.33%) are not aware of existence of the cassava peeling machine. In addition, we find that 99.63% of the cassava processors are willing to patronize the services of the cassava peeling machine. Moreover, cassava processors are willing to pay an average amount of GH₵ 4.21 for a 50 kg bag of cassava peeled using the services of the cassava peeling machine. Furthermore, the study revealed that factors such as educational level, quantity produced per processing cycle and the dependence on cassava processing as the main source of income positively and significantly influenced willingness to pay for the services. Finally, the amount processors were willing to pay was influenced by educational level, household size, source of income, perception about machine’s complications and group membership. The study recommends that investors consider installing cassava peeling machines to provide commercial cassava peeling services in processing areas. While generating income to investors, it will contribute to reducing postharvest losses during cassava processing. Future efforts should focus on raising awareness about the availability and benefits of commercialization of mechanized peeling of cassava.

EFFECT OF ETHANOLIC EXTRACT OF BLACK PEPPER (Piper nigrum) ON PRESERVATION OF AFRICAN CATFISH (Clarias gariepinus)

Fish preservation is an important stage of fish production as it helps in the reduction of post-harvest losses. This leads to the study of ethanolic extract of black pepper as a preservative of African catfish. A sample size of five (5) fish of average weight 600g for each treatment were slaughtered and gutted before they were dipped in the black pepper extract for 10minutes and 20 minutes in separate bowls. The fish samples that had been preserved with the plant extract were monitored for spoilage at an interval of four (4) hours for the period of forty eight (48) hours and the organoleptic characteristics were observed and recorded. The shelf life of the experimental African catfish was extended from 20 hours as seen in the unpreserved sample to between 24 – 26 hours in the preserved sample. The study also indicated that the duration of dip did not have any effect on the preservative action of black pepper seed extract and this was because the extract was only able to extend the shelf life of the sample to 24 – 26 hours before becoming unfit for consumption at 28 hours for both the 10 and 20 minutes dipping durations. It can therefore be concluded from the findings of this research that African catfish can be preserved using natural preservatives (plants) and thereby reducing post-harvest losses.

Nutritional and Sensory Evaluation of Yoghurt Incorporated with Unripe False Horn Plantain (Musa paradisiaca var. "apentu").

Unripe plantain (Musa paradisiaca L.) is rich in nutrients including minerals, vitamin C, and carbohydrates particularly resistant starches with prebiotic properties. However, the fruit is challenged with limited utilisation, and this contributes to its high postharvest losses along the production and supply chain. Information is lacking on incorporating plantain (UPF) in functional dairy food product development. In a completely randomized design, the study evaluated the effect of unripe false horn plantain (var. "apentu") flour (UPF) incorporation (w/v), at 0% (control), 2%, 4%, and 6%, on the composition and sensory quality of yoghurt. The results showed that higher UPF percent incorporation resulted in yoghurts having lower moisture and higher total solid values as well as enhanced nutritional values, in terms of protein, zinc, potassium, calcium, and vitamin C (P < 0.05). Mean pH and total titratable acidity values of the yoghurt products were in the ranges of 3.40-3.65 and 1.00-130%, respectively. Conversely, an increase in UPF incorporation generally reduced consumer likeness scores for yoghurt sensory characteristics including appearance, texture, flavour, taste, aftertaste, and overall acceptability. The control AZ product received the highest ratings in all sensory attributes evaluated. Compared with the control AZ, the BX (2% w/w UPF) yoghurt showed better nutritional quality as well as had comparable ratings for the sensory attributes, particularly in terms of appearance, texture, and flavour. Thus, the formulation containing 2% UPF has the best potential for the production of value-added functional yoghurt, which will be acceptable. However, for high acceptability, further research is needed to improve the impact of UPF incorporation on the overall sensory quality of yoghurt. The study suggests that UPF can serve as a potential supplement for improving the value of yoghurt, and this also contributes to reducing postharvest losses of plantain as a key food security resource. Also, the study findings contribute baseline information to guide future research on functional dairy product development with unripe plantain.

Yieldwise model adoption on post-harvest loss reduction and livelihood of smallholder maize farmers in the Wa Municipality of Ghana

This study sought to assess the impact of adoption of the YieldWise model on postharvest loss reduction and livelihood of smallholder maize farmers in the Wa Municipality using an established crop aggregation center, Antika for a case study. The study employed random and purposive sampling techniques to sample 140 smallholder maize farmers and 10 Antika crop aggregation center managers in the Wa Municipality. A well-structured questionnaire was used to obtain data from the selected sample population. The findings revealed that the timelines of input supply, ready market, access to extension service, availability of recommended inputs, and training on post-harvest loss reduction are factors influencing the adoption of the YieldWise model by smallholder farmers in the Wa Municipality. The availability of recommended inputs was the main influencing factor, followed by access to extension service, while ready market was the least. The introduction of the YieldWise model had an impact on the harvesting and postharvest loss reduction among smallholder maize farmers in the selected study area. The adoption of the model contributed to a reduction in harvesting losses by an average of 46.24 kg/ha (25.66 %), reduction in shelling and threshing losses by 28.11 kg/ha (19.74 %), reduction in storage losses 12.85 kg/ha (54.99 %), whereas transportation losses remained almost same; thus, 0.62 kg/ha and 0.68 kg/ha for Antika and non-Antika farmers respectively. The study revealed that, the adoption of the YieldWise model by Antika for it business operation has contributed to the improvement of the livelihood of smallholder maize farmers in the Wa Municipality. Many farmers (30.4 %) could secure food for their families throughout the year, 26.5 % could pay for their children’s school fees, 17.1 % of the farmers have been able to purchase a motorcycle or tricycle, 11.1 % of the farmers have been able to expand their main occupation, 10.6% have built new houses, and 4.3 % have been able to marry. The study recommends that a ready market is incorporated into the YieldWise model to help farmers market their produce promptly. The model should also consider transportation assistance to smallholder farmers to reduce transportation losses.

Subsidy strategies of grain supply chain considering stakeholder efforts on post-harvest loss reduction and pollution emission reduction

Subsidy strategies of grain supply chain considering stakeholder efforts on post-harvest loss reduction and pollution emission reduction

Bay Leaves Extracts as Active Additive for Food Protective Coatings.

Ethanolic extracts of bay leaves were obtained using the Soxhlet method (extraction yield of 22.3 ± 1.2%) and further analyzed through different methods, thus determining the chemical composition with gas chromatography, phenolic content with the Folin-Ciocalteu technique (11.8 ± 0.4% wt.) and antioxidant power with the radical 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) method (75.06%). Furthermore, its effect on the growth of two bacteria, Escherichia coli and Bacillus cereus, and on two yeasts, Candida glabrata and Saccharomyces cerevisiae, was determined, showing a minimum inhibitory concentration of 0.65 mg/mL on the growth of B. cereus. Finally, edible films were prepared using different polymers (carboxymethyl cellulose, gum Arabic, polyvinyl pyrrolidone, and polyvinyl alcohol) containing 0, 5, 10, or 15% wt. of bay leaf extract as troubleshooting for perishable fruits, specifically for cultivated strawberry. The prepared composites presented reduced water vapor permeabilities (up to 4.3 × 10-7 g·Pa-1·m-1·h-1), high specific transparencies (≈30%/mm), as well as the effective blocking of ultraviolet radiation (>99.9%). In vivo tests showed that the most suitable treatment for strawberry protection was the impregnation with a composite comprising polyvinyl alcohol and a 15% wt. bay leaf extract, resulting in a noteworthy reduction in mass loss (22% after 6 days). It can be asserted that food packaging with the designed composites would be an effective alternative for the reduction in postharvest losses.

Molecular characteristics of some Botrytis isolates and antagonistic activity of Bacillus subtilis and its bacteriocin on tomato fruit

Gray mold, caused by Botrytis cinerea, is one of the most devastating agricultural diseases during the pre and postharvest stages. This study aims to investigate the application of Bacillus subtilis as a bioagent against B. cinerea and reducing pre and postharvest disease as a replacement method to chemical pesticides. Five Botrytis isolates were molecularly confirmed and the virulent isolate BC2 was registered for the first time in the National Center of Biotechnology Information (NCBI) with accession number OP257237. The mycelial growth of B. cinerea was inhibited by up to 84% when treated with the bio agent bacterium using the double drawing method in Petri plates. Pre-harvest application of B. subtilis at a concentration of 108/ml CFU reduced postharvest -gray mold of tomato fruit during ripening stages in the greenhouse. Preharvest application of bioagent bacterium B. subtilis induced the levels of B-1, 3-glucanase and Polyphenol oxidase, indicating enhanced plant resistance to gray mold. Disease severity was decreased compared with control and extended the shelf life at 25 °C.The field application of the bio agent bacterium at the maturity of ripening in preharvest had a significant effect on increasing the level of polyphenol oxidase PPO and B-1, 3-glucanase, which are related to the enhancement of plant defenses and resistance. Additionally, it led to an increase in storage life and a reduction in post-harvest losses. The results demonstrated that preharvest application of bio agent bacterium Bacillus subtilis improved the quality of postharvest tomato fruit and significantly reduced gray mold incidence, all without the use of chemical pesticides.

Effect of Different Doses of Calcium and Boron Pre-harvest Spray on Post-harvest Quality of Acid Lime (Citrus aurantifolia var. SunKagati-1)

Acid Lime (Citrus aurantifolia var. SunKagati-1) has been cultivated in 67 districts of Nepal. Its cultivation is becoming increasingly popular among farmers in Nepal. However, adequate post-harvest loss reduction measures are lacking. A field experiment was conducted in lime orchards in Chitwan during August-September 2019 and 2020. Pre-harvest spraying of different concentrations of calcium (0.1, 0.2, and 0.3%) and boron (0.2, 0.4, and 0.6%) in lime fruit trees was done before 45 and 30 days of fruit harvest. Fruits with the same maturity indices were harvested separately from the treated plants. The post-harvest study was conducted for 1 month under laboratory conditions. Different parameters like physiological loss of weight (PLW), decay loss, total soluble solids (TSS), titrable acidity (TA), ascorbic acid content (vitamin C), and freshness were recorded. Minimum PLW (18.2%) and decay loss (14.3%) were observed in boron (@0.6%) treated fruits. At the end of the experiment, minimum TA (1.79 and 2.12%) was recorded from boron (@0.6%) treated fruits in both years. Calcium (@0.3 %) and boron (@0.4 %) treated fruits expressed the maximum values for TSS in 2019 (9.67ºbrix) and 2020 (7.73 ºbrix), respectively. Fruit harvested from fruit trees sprayed with boron (@0.6%) showed the highest ascorbic acid content (55.47 and 49.61 mg/100g) and better lime freshness (2.67 and 3.0) in 2019 and 2020, respectively. This study concluded that the use of boron @0.6% as a pre-harvest spray can prolong the storage life of sour lime and maintain the fruit quality under environmental conditions of a mid-hill situation.

Analyzing the existing value chains of fruits and vegetables in selected upazilas of Bangladesh

Reducing postharvest losses of fruits and vegetables is a major pathway to food and nutrition security in Bangladesh. A survey was conducted in 30 selected upazilas of Bangladesh from February to October 2021 to explore the nature and magnitude of postharvest losses. This study assessed the knowledge gap, attitudes and practices of the value chain’s key actors, and the status of market opportunities in the country. A total of 515 farmers and 295 traders were interviewed from selected upazilas of the country. The findings of this study revealed that 50-70% of growers showed a positive attitude toward good agriculture practices (GAP), maturity indices, and the role of good packaging in keeping the products safe for consumers. More than 41% of farmers aggregated their harvested commodities beside the field on direct soil contact under open sunlight. Only 27% of farmers and traders washed fruits and vegetables before marketing, of which 32% used unsafe water found in the canal or ditches. On average, 86.91% of farmers and traders sorted out their products before marketing for a better price. More than 56% of farmers and traders used jute or nylon sac for packaging fresh fruit and vegetables. Nevertheless, only 20.2% of farmers and 24.41% of traders used plastic crates as packaging containers. Generally, the farmer used different local vehicles, including three-wheeler van, rickshaw, bi-cycle, tempo, etc. In contrast, the traders transported their produce to the wholesale market using a truck and pick-up van. The average postharvest losses were estimated 12.5% at the farm level, whereas 6.7% at trader’s level up to the wholesale market. Int. J. Agril. Res. Innov. Tech. 13(1): 123-130, June 2023

Spoilage Monitoring and Early Warning for Apples in Storage Using Gas Sensors and Chemometrics.

In the process of storage and cold chain logistics, apples are prone to physical bumps or microbial infection, which easily leads to spoilage in the micro-environment, resulting in widespread infection and serious post-harvest economic losses. Thus, development of methods for monitoring apple spoilage and providing early warning of spoilage has become the focus for post-harvest loss reduction. Thus, in this study, a spoilage monitoring and early warning system was developed by measuring volatile component production during apple spoilage combined with chemometric analysis. An apple spoilage monitoring prototype was designed to include a gas monitoring array capable of measuring volatile organic compounds, such as CO2, O2 and C2H4, integrated with the temperature and humidity sensor. The sensor information from a simulated apple warehouse was obtained by the prototype, and a multi-factor fusion early warning model of apple spoilage was established based on various modeling methods. Simulated annealing-partial least squares (SA-PLS) was the optimal model with the correlation coefficient of prediction set (Rp) and root mean square error of prediction (RMSEP) of 0.936 and 0.828, respectively. The real-time evaluation of the spoilage was successfully obtained by loading an optimal monitoring and warning model into the microcontroller. An apple remote monitoring and early warning platform was built to visualize the apple warehouse's sensors data and spoilage level. The results demonstrated that the prototype based on characteristic gas sensor array could effectively monitor and warn apple spoilage.

What factors impact the adoption of postharvest loss-reduction technologies in mangosteen supply chain?

As one of Indonesia's high-value export fruit commodities, mangosteen has the highest postharvest loss (PHL) value, which significantly affects the economy. This study investigates the determinants of technology adoption to reduce PHL and the challenges faced by supply chain actors in West Java Province, Indonesia. A structural equation model was employed to analyze the data gathered from farmers and middlemen. Additionally, in-depth interviews were conducted with exporters and modern market managers to obtain relevant information. The study found that capabilities, infrastructure, and financial access were the critical factors for farmers, whereas infrastructure and risk perceptions were identified as crucial for middlemen. The determinants of exporters’ adoption are customer specifications, food safety standards, and technology availability. Retailers, on the other hand, closely associated quality consistency requirements, buyer preferences, and risk considerations with technology adoption. This study proposes initiatives and policies to promote the adoption of technologies to reduce PHL in the mangosteen supply chain.

Impact of PYXERA Global Yieldwise Project on Improved Tomato PostHarvest Loss Management Practices of Farmers’ Output, Income and Poverty Status in North-West Zone, Nigeria

The study was conducted to determine the impact of PYXERA Global Yieldwise project improved tomato postharvest loss management practices on farmers output, income and poverty status in North-West Zone, Nigeria. A multi-stage random selection method was used to choose the study locations, and 540 farmers were administered with structured questionnaire. Data were analyzed using the descriptive, double difference estimates and FGT poverty index. The results showed that the difference in value between the two output differences [?211,255.8 – ?128,366.86] was N82, 888,94. The poverty incidence of poor farm households in the study area was 95% for the non-adopters, and 61% for the adopters. In addition, the poverty depth among the farm households in the study area was 85% for non–adopters and 36% for adopters. The severity of the poverty index was 79% for non–adopters and 26% for adopters of improved tomato post-harvest loss reduction management practices. This implies that poverty incidence is higher among non-adopting poor than their adopting poor households. The study concluded that the adoption of the improved tomato post-harvest management practices had a positive impact on tomato postharvest loss reduction, income, and poverty status as revealed in the results of this study, although the extent of tomato post-harvest loss was still high. It was therefore recommended that the tomato post-harvest loss reduction campaign should be sustained to further decrease the losses suffered by tomato farmers especially as the end line for achieving the SDG on food loss and food waste draws closer. All stakeholders in the tomato value chain should address other challenges limiting the adoption of improved tomato production and post-harvest loss reduction such as low extension visits, poor market linkages, and distance to market.

Breaking the barrier against the purchase of cold meat in Tanzanian consumers for reduction of postharvest losses and improved investment in cold chains: A review

Suppose the realization of Tanzania’s government’s commitment to industrialize the country is to be achieved. In that case, the certainty of value addition to agricultural produce and the resulting extensive supply chain, encompassing meat, becomes apparent. Without the development and utilization of cold chains, progress toward industrialization in the meat industry remains unattainable. Considering the current infrastructure of cold chains in Tanzanian abattoirs, meat processing plants, and specialized retail establishments, the estimated cold storage capacity stands at 6,700 tons of meat per day, equating to 39 kg per capita annually. Despite this capacity, approximately 100,000 metric tons of meat, equivalent to 15% of Tanzania’s yearly production, are lost due to postharvest losses and waste. This substantial loss could be significantly mitigated by appropriately implementing cold chains. However, over 90% of meat consumers in Tanzania and other African countries prefer to purchase warm meat and exhibit an aversion to cold meat. This consumer preference hinders comprehensive investment and the adoption of cold chains in the meat industry to reduce meat spoilage and postharvest losses. To overcome this barrier and bolster industrialization in Tanzania’s meat industry, a three-tier approach is necessary: coordinated consumer awareness campaigns to promote the suitability of cold meat, widespread training of stakeholders in the value chain regarding proper meat handling and storage practices, and the implementation of adequate legislation to guide the gradual transformation of the supply chain towards the provision of cold meat. In conclusion, the current cold storage capacity for meat in Tanzania primarily serves export and niche markets. Efforts are required to shift local consumers’ attitudes towards cold meat, enabling comprehensive investment and utilization of the cold chain in the meat industry to mitigate postharvest meat losses.

Experimental Investigation for Augmentation of Thermal Performance of Solar Air Collector

This paper presents a study of the thermal performance of a solar air collector used to heat the drying air of a fruit and vegetable dryer. The prototype collector could be a viable solution to improve energy efficiency and food security in Burkina Faso and other developing countries, by contributing to the reduction of post-harvest losses and the increase of income for local agricultural producers. The collector is first realized by using black painted cans as air ducts, perforated to increase turbulence, and a glass covering the collection surface. After realization, the collector is connected to the dryer and a measurement campaign is conducted to evaluate the thermal performance of it. The measured parameters are the sunshine and the air temperature by keeping the air speed fixed at 0.3 m/s. The analysis of the results shows an important variation of the air temperature difference going from 0.1°C to 74.4°C, between the inlet and the outlet of the collector for an irradiation which varies between 142 W/m2 and 837 W/m2. The black painted surface of the air ducts as well as the increase in turbulence contributed to improve the efficiency of the collector which varies between 0.94% and 50.68% and allowing to record air temperatures ranging from 27.2°C to 69.2°C inside the dryer. This temperature range is favorable for the drying of most food products.

English

The present study was conducted to check nutritional characterization i.e., proximate analysis, physicochemical properties (total soluble solid content, titratable acidity, texture, and color), phytochemicals (total phenolic, flavonoids and anthocyanin) and antioxidant capacity (DPPH-2,20-diphenyl-1-picrylhydrazyl radical scavenging capacity) of strawberry varieties (festival, chandler and korona) produced in Pakistan along with shelf life extension using modified atmosphere packaging (MAP) technology. Accordingly, samples were collected from farms and local market for analysis. Results showed statistically differences (p&lt; 0.05) for proximate composition expect ash and crude fat. Higher moisture content documented in variety chandler as 91.12±7.28%, highest ash in variety korona as 1.4±0.17%, lowest protein in variety Chandler as 0.95±0.13% and highest fat in variety festival as 1.13±0.31. Physicochemical analysis showed highest titratable acidity as 0.70±0.04 g citric acid/100g in variety chandler, highest ○Brix as 8.41±0.11in variety festival whereas, phytochemicals analysis revealed highest total phenolic and flavonoids found in variety chandler as 926.17±53.08 mg GAE/100 g and 180.63±15.72 mg/100g respectively, and lowest 864.44±44.16 mg GAE/100 g, 144.84 ± 12.11 mg/100g in variety korona, respectively. The variety chandler displayed highest antioxidant activity (82.09±6.34%) and anthocyanin (2.74 ± 0.09 mg/100g however, non-significant differences in color values. Further, the shelf life of strawberries was extended by 09 days by modified atmospheric packaging under cold storage for 12 days. For this strawberry was categorized into 5 groups with the different gas combination i.e., MAP0 (control group having 0.05% CO2, 20.95% O2 and 79% N2), and 4 treatment groups MAP1 (3% CO2, 15% O2 and 82% N2), MAP2 (5% CO2, 10% O2 and 85% N2), MAP3 (10% CO2, 5% O2 and 85% N2), MAP4 (15% CO2, 3% O2 and 82% N2). Statistical differences (p&lt; 0.05) were found between groups on different storage days (3rd, 6th, 9th, and 12th) in physiochemical, phytochemical, sensory evaluation, and caloric parameters. In nutshell, the results provide valuable information on the nutritional composition, phytochemical characteristics, and quality aspects of strawberries produced in Pakistan. This information is helpful for food processors in value addition, and modified atmosphere packaging technology for the reduction of post-harvest losses.

MODELING OF THE WATER ADSORPTION ISOTHERM OF MANGO SLICES (MANGIFERA INDICA L.) DRIED UNDER HOT AIR

The general objective of this work is to contribute to the reduction of post-harvest losses of mangoes by the transformation into stable dried products.This research aims to determine the best storage conditions for dried mangoes.Thus, the water adsorption isotherms of mango slices dried under hot air were experimentally determined by the static thermogravimetric method at 25°C.Eight mathematical models from the literature were used (GAB, BET, Hasley, Henderson, Harking and Dura, Oswin, Chung and Pfost, Smith) to describe the hygroscopic behavior of dried mango slices.Regression analysis was performed using MatLab R2016a software to determine the coefficients, model parameters and statistical parameters of the smoothing.The results revealed that the equilibrium is obtained from 35 days for the two samples and the adsorption isotherms determined are of type II characterized by a sigmoidal shape.In addition, the three-parameter (GAB) model showed good agreement with the experimental data (r= 0.999 and 0.997 respectively for slices with thicknesses of 1cm and 1.5cm) at 25°C.The water content of the mono-molecular layer is 2.295% at 25°C for the 1cm slices and 2.289% at 25°C for the 1.5cm slices.The net isosteric heat of adsorption tends towards zero for high water contents (0.052KJ/mol at 44.472% water).The linearity between enthalpy (net isosteric heat) and differential entropy of adsorption shows their compensation.