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1 – 10 of over 1000
Article
Publication date: 19 August 2021

B. Norerama D. Pagukuman and M. Kamel Wan Ibrahim

The purpose of this paper is to present and discuss the external factors of the solar dryer design that influenced the thermal efficiency of the solar dryer that contribute to the…

Abstract

Purpose

The purpose of this paper is to present and discuss the external factors of the solar dryer design that influenced the thermal efficiency of the solar dryer that contribute to the better quality of dried food products.

Design/methodology/approach

From the reviewed works of literature, the external factors including the drying temperature, airflow rate and relative humidity have significant effects to increase the rate of moisture diffusivity of the freshly harvested products during the drying process. The proper controls of airflow rate (Q), velocity (V), relative humidity (RH%) and drying temperature (°C) can influence the dried product quality. The dehydration ratio is the procedure to measure the quality of the dried food product.

Findings

The indirect solar dryer including the mixed-mode, hybrid and integrated was found shorter in drying time and energy-intensive compared to sun drying and direct drying. The recommended drying temperature is from 35.5°C to 70°C with 1–2 m/s velocity and 20%–60% relative humidity. The optimum thermal efficiency can be reached by additional devices, including solar collectors and solar accumulators. It gives a simultaneous effect and elongated the drying temperature 8%–10% higher than ambient temperature with 34%–40% energy saving. The recommended airflow rate for drying is 0.1204 to 0.0894 kg/s. Meanwhile, an airflow rate at 0.035–0.04 kg/m2 is recommended for an optimum drying kinetic performance.

Research limitations/implications

This paper discusses the influence of the external factors of the solar dryer design on the thermal performance of the solar dryer and final dried food products quality. Therefore, the findings cannot serve as a statistical generalization but should instead be viewed as the quantitative validation subjected to fundamentals of the solar dryer design process and qualitative observation of the dried food product quality.

Practical implications

A well-designed of solar dryer with low operating and initial fabrication cost, which is simple to operate is useful for the farmers to preserve surplus harvested crops to an acceptable and marketable foods product. The optimization of the external and internal factors can contribute to solar dryer thermal performance that later provides an organoleptic drying condition that results in good quality of dried product and better drying process. The recommended drying temperature for a drying method is between 35°C up to 70°C. Drying at 65.56°C was effective to kill microorganisms. Meanwhile, drying at 50°C consider as average drying temperature. The recommended airflow rate for drying is 0.1204 to 0.0894 kg/s. Meanwhile, air flowrate at 0.035–0.04 kg/m2 is recommended for optimum drying kinetic performance. The recommended value of aspect ratio and mass flow rate is 200 to 300 for an optimum evaporation rate. The good quality of dried products and good performance of solar dryers can be developed by proper control of airflow rate (Q), velocity (V), relative humidity (RH%) and drying temperature (°C).

Social implications

The proper control of the drying temperature, relative humidity and airflow rate during the drying process will influence the final dried food products in terms of shape, color, aroma, texture, rupture and nutritious value. It is crucial to control the drying parameters because over-drying caused an increment of energy cost and reduces the dry matter. The quick-drying will disturb the chemical process during fermentation to be completed.

Originality/value

This study identifies the potential of the solar drying method for dehydrating agricultural produces for later use with the organoleptic drying process. The organoleptic drying process can reduce mold growth by promising an effective diffusion of moisture from freshly harvested products. The research paper gives useful understandings that well-designed solar drying technology gives a significant effect on dried product quality.

Details

Journal of Engineering, Design and Technology , vol. 20 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 February 2022

Ataollah Khanlari, Faraz Afshari, Adnan Sözen, Azim Doğuş Tuncer and Barış Kusun

During the past several years, research and studies in the field of solar energy have been continuously increased. One of the substantial applications of solar energy is related…

Abstract

Purpose

During the past several years, research and studies in the field of solar energy have been continuously increased. One of the substantial applications of solar energy is related to industrial utilization for the drying process by efficient heat transfer methods. This study aims to upgrade the overall performance of an indirect solar dryer using a solar absorber extension tube (SET) equipped with ball-type turbulators.

Design/methodology/approach

In this work, three various SETs including hollow (SET Type 1), 6-balls (SET Type 2) and 10-balls (SET Type 3), have been simulated using Fluent software to evaluate heat transfer characteristics and flow structure along the air passage. Then, the modified solar drying system has been manufactured and tested at different configurations.

Findings

The findings indicated that adding a SET improved the performance notably. According to the results, using turbulators in the tube has a positive effect on heat transfer. The highest overall thermal efficiency was found in the range of 51.47%–64.71% for the system with SET Type 3. The maximum efficiency increment of the system was found as 19% with the use of SET. Also, the average specific moisture extraction rate, which is a significant factor to survey the effectiveness of the dehumidification system was found between 0.20 and 0.38 kg kWh−1.

Originality/value

In the present study, a novel SET has been developed to upgrade the performance of the solar dehumidifier. This new approach makes it possible to improve both thermal and drying performances.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 24 July 2019

Ita Sulistyawati, Siet Sijtsema, Matthijs Dekker, Ruud Verkerk and Bea Steenbekkers

The purpose of this paper is to explore consumers’ health perception and demonstrate its relevance in product and process design in early stages of new product development.

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Abstract

Purpose

The purpose of this paper is to explore consumers’ health perception and demonstrate its relevance in product and process design in early stages of new product development.

Design/methodology/approach

A dried mango was used as a case study involving three countries: Indonesia, China and the Netherlands. Data were collected from nine focus groups (n=53 participants) and were content-analysed to acquire in-depth insights.

Findings

Four themes of health perception emerged, namely, nutrition, naturalness, taste and well-being, which were all expressed on different levels of abstractness. Participants’ health perception of dried mango varied, it is related to the product category it is compared with, e.g. candy or fresh fruit, and the eating context, e.g. position in the diet either as a snack or a meal. In extension participants mentioned product and process characteristics. Application of the insights into product and process design was performed through iterative interactions between consumer scientists and food technologists. The development of two product concepts was elaborated to transform the insights into technical product and process specifications for a natural dried mango product.

Originality/value

This transformation suggests that iterative interactions are necessary to achieve relevant product and process characteristics in the simultaneous design of the technical product and process specifications based on consumer perceptions.

Details

British Food Journal, vol. 121 no. 9
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 8 August 2019

Samuel Ayofemi Olalekan Adeyeye

Fishes are important sources of good and high-quality protein in developing countries. Spoilage and keeping quality of fish especially in the tropics is temperature dependence as…

Abstract

Purpose

Fishes are important sources of good and high-quality protein in developing countries. Spoilage and keeping quality of fish especially in the tropics is temperature dependence as high temperature and relative humidity accelerate the process of spoilage and fish keeping quality. Fish dehydration removed moisture and extended the shelf life of dried fish. Drying involves removal of moisture from fish as a result of heat and mass transfer done under controlled conditions. This study delves into various drying techniques and drying kinetics of fish.

Design/methodology/approach

The review examines fish drying kinetics and the various drying models applicable to fish drying.

Findings

This review showed that moisture content and colour of dried fish are affected by time and power level. It was also found that the moisture content of the dried fish varied according to the drying method used. Also, as drying power and drying rate varied inversely with drying time. Eight different thin layer drying models were examined for evaluation of drying data for all the experimental conditions involving fish drying. It was found that the quality of the dried fish decreased with drying. Higher values of effective moisture diffusivity have been found to increase moisture velocity within fish samples which improve removal of moisture to reach equilibrium moisture content at specified relative humidity. However, based on this, effective moisture diffusivity could be a useful parameter to design an effective drying method in terms of time, energy consumption and cost to prolong the storage life of dried fish samples. Drying kinetics and different drying models were considered and explained. The use of these models was considered to be important in choosing appropriate drying conditions for effective drying and to get good quality dried fish samples.

Research limitations/implications

The review considers few available literatures on the subject matter.

Practical implications

The review explores the possibility of creating more awareness for more in-depth research on fish drying kinetics and their usefulness in fish preservation.

Originality/value

This outcome of this study is important to researchers, policymakers and regulatory agencies in developing countries on fish preservation.

Details

Nutrition & Food Science, vol. 49 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 7 August 2023

Serafina Stone, Zannie Langford, Risya Arsyi, Imran Lapong, Zulung Zach, Radhiyah Ruhon, Boedi Julianto, Irsyadi Siradjuddin, Annie Wong and Scott Waldron

Poor post-harvest handling practices by seaweed farmers are a key issue in seaweed value chains, contributing to low-quality seaweed being supplied to processors. To address this…

Abstract

Purpose

Poor post-harvest handling practices by seaweed farmers are a key issue in seaweed value chains, contributing to low-quality seaweed being supplied to processors. To address this, a range of advanced drying technologies and methods have been developed, yet uptake by farmers remains low. This study examines factors affecting drying technology uptake by seaweed farmers to identify opportunities to incentivise improved drying practices.

Design/methodology/approach

This study draws on a quantitative survey of 273 seaweed farmers in two villages in South Sulawesi, 16 months of ethnographic fieldwork and 166 semi-structured interviews.

Findings

Farmers engage in limited adoption of improved drying technologies and practices as they don't receive higher prices for higher quality products, instead aiming to meet only the minimum acceptable standards to avoid a price discount or rejection of their product. Technologies and techniques that have been adopted are often used in ways that differ from their original purpose, such as to reduce drying times and labour input, rather than to produce products of low moisture and dirt contents. Similarly, local traders mix high- and low-quality seaweed in order to supply warehouses with seaweed which on average meets minimum quality standards.

Originality/value

This study reveals that improved drying practices are unlikely to be adopted unless incentivised by more targeted price-grade differentials.

Details

Journal of Agribusiness in Developing and Emerging Economies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2044-0839

Keywords

Article
Publication date: 24 February 2012

Emmanuel Kanchebe Derbile and Raymond Abudu Kasei

The purpose of this paper is to analyze vulnerability of food crop production to heavy precipitation in north-eastern Ghana, specifically, the upper east region (UER) and the…

Abstract

Purpose

The purpose of this paper is to analyze vulnerability of food crop production to heavy precipitation in north-eastern Ghana, specifically, the upper east region (UER) and the policy implications for adaptation. Heavy precipitation events are a common part of climatic variability; but little attention is given to its impact on livelihoods as compared to droughts in research and policy domains.

Design/methodology/approach

This paper draws on both quantitative and qualitative research methods and data. Rainfall data are analyzed using the Standardized Precipitation Index (SPI). This is compared with quantitative analysis of crop yields and complemented by narratives of farmers from in-depth interviews and focus group discussions.

Findings

The results show that heavy precipitation events often lead to low food crop productivity and this suggests that the latter is vulnerable to the former.

Originality/value

Although some adaptation is occurring through a wide range of local measures, these are inadequate for eliminating vulnerability. Thus, additional policy measures are recommended for enhancing farmer adaptation, including: incorporating climate change adaptation policies, including adaptation to heavy precipitation into District Development Planning; building human resource capacity for effective implementation of climate change adaptation policies at district levels; improving market access to seed through improved market infrastructure and rural transportation; establishing Community Seed Banks (CSBs) as back up sources of seed; promoting “nursing and transplant” as an alternative planting method for millet and guinea corn; promoting low costs solar drying technologies for drying food crops; and supporting livelihood diversification through credit and business development services.

Details

International Journal of Climate Change Strategies and Management, vol. 4 no. 1
Type: Research Article
ISSN: 1756-8692

Keywords

Abstract

Details

Entrepreneurs’ Creative Responses to Institutional Challenges
Type: Book
ISBN: 978-1-83909-542-9

Article
Publication date: 3 May 2013

M.Y. Abdollahzadeh Jamalabadi, M. Ghassemi and M.H. Hamedi

Natural convection heat transfer combined with radiation heat transfer is used in electronic cooling. The purpose of this paper is to investigate the thermal loading…

Abstract

Purpose

Natural convection heat transfer combined with radiation heat transfer is used in electronic cooling. The purpose of this paper is to investigate the thermal loading characteristics of an enclosure.

Design/methodology/approach

The goal is to investigate the effect of thermal radiation on thermal and flow characteristics of the cavity. The enclosure lower wall is at constant temperature and the upper wall is adiabatic while there are several discrete heat sources inside the cavity. In addition the effect of parameters such as heating number (Nr), aspect ratio (A), the number of heaters (N), and thermal radiation on the maximum and mean temperature of system, thermal loading characteristics of the system, Nusselt number, and the maximum stream function rate is performed. To solve the governing nonlinear differential equations (mass, momentum, and energy), a finite‐volume code based on Patankar's SIMPLE method is utilized.

Findings

Heat transfer by natural convection solely and it's conjugation with thermal radiation on the thermal and flow characteristics of the system is studied. Also a parametric study illustrating the influence of the heating number, aspect ratio, the number of heaters, and thermal radiation on the maximum and mean temperature of system, thermal loading characteristics of the system, Nusselt number, and the maximum stream function rate is investigated. The results have revealed that the thermal radiation have an important effect on the thermal characteristics of system at low heating numbers.

Research limitations/implications

The relevant governing parameters were: the heating number, Nr from 0.05 to 500, the cavity aspect ratio, A=H/L from 0.1 to 1 and the number of heaters, N, is an odd number ranging from 1 to 19

Practical implications

This work is numerical investigation only but can have engineering application such as electronic cooling, transformers, fusion reactors technology, hot structures, fuel cells, fibrous insulations and solar‐energy drying systems.

Originality/value

The effect of radiation in enclosure with discrete heaters within fluid has not been addressed in the literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 6 July 2015

Roselyne Alphonce, Anna Temu and Valerie Lengard Almli

The purpose of this paper is to assess European consumer preference and willingness to pay (WTP) for tropical dried fruits from Africa. The paper specifically investigates sensory…

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Abstract

Purpose

The purpose of this paper is to assess European consumer preference and willingness to pay (WTP) for tropical dried fruits from Africa. The paper specifically investigates sensory and credence characteristics driving consumer preferences.

Design/methodology/approach

Data on sensory descriptive analysis and hedonic evaluation for seven samples representing three fruit types: mango, pineapple and banana, were collected together with data on Country of Origin (COO) preferences and WTP for conventional, organic and fair-trade labelled dried fruits, among Norwegian consumers (n=96).

Findings

The results show that consumer preferences for a dried fruit are affected significantly by its typical aroma intensity and consumers are willing to pay a premium for both organic and fair-trade products. Two consumer groups expressing distinct COO preferences for tropical dried fruits and a third group with no country preferences are revealed.

Originality/value

This study provides useful insights for dried fruit producers and market strategists in tropical countries attempting to position value-added products for maximum revenue.

Details

British Food Journal, vol. 117 no. 7
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 5 September 2016

Andreas Beneking, Saskia Ellenbeck and Antonella Battaglini

Following the issuance of the Renewable Energy Directive in 2009, the European Union (EU) is explicitly pushing for member states to cooperate with third countries to meet their…

Abstract

Purpose

Following the issuance of the Renewable Energy Directive in 2009, the European Union (EU) is explicitly pushing for member states to cooperate with third countries to meet their EU 2020 targets. So far, no single joint project is planned or in place yet. This paper aims to look at the opportunities for and barriers to possible RE exports from North Africa into the EU through the concept of a SWOT (strengths, weaknesses, opportunities and threats) analysis.

Design/methodology/approach

Thus, the SWOT for a possible implementation of Article 9 projects are analyzed using expert and stakeholder knowledge. A qualitative assessment was undertaken using data collected through one stakeholder workshop in North Africa, in-depth interviews and a qualitative literature review. The analysis was structured within a three-tier analyzing concept distinguishing between macro, micro and acceptance parameters.

Findings

From the SWOT analysis, some lessons are drawn, future possible measures are identified and conclusions for policymakers are discussed. The authors find that no easy solutions exist as most parameters can be both a strength and a weakness or a threat and an opportunity at the same time depending on future developments and the specific ideological perspective.

Originality/value

This paper provides new information and analysis of renewable energy sources projects in North Africa – application of the SWOT method on Article 9 cooperation projects – application of a three-tier analysis to cope with the complexity of the topic – taking into account often neglected socio-political aspects such as public acceptance.

Details

International Journal of Energy Sector Management, vol. 10 no. 3
Type: Research Article
ISSN: 1750-6220

Keywords

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