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Smart Monitoring System Design for Perishable Food Supply Chain Management Based on IoT in Bangladesh
Arefin Islam Sourav1, Ninyikiriza Deborah Lynn1, Suyoto2
1MasterStudent, Department of Informatics Engineering, UniversitasAtma Jaya Yogyakarta, Indonesia
2Professor, Department of Informatics Engineering, UniversitasAtma Jaya Yogyakarta, Indonesia
suyoto@staff.uajy.ac.id Abstract
Background: Quality monitoring and control of perishable food products is an ongoing issue along with the food supply chain management in Bangladesh. A large amount of perishable food products is being wasted every day in the storage process due to poor management and insufficient monitoring systems.
Environmental factors like – temperature, humidity, light, air quality and microorganisms in closed storage environments may lead to quick food spoilage.
An IoT based smart monitoring system can be introduced to monitor all these factors more effectively.
Objective: This paper addresses the application of an IoT based automated smart system to monitor environmental variations in a closed food storage area.
Method: The method applied is combining four Arduino microcontroller compatible sensors. The sensors will monitor the surroundings and trigger sever-al environmental controlling devices. The whole system can be observed from a mobile application.
Result: With the ongoing research, it is expected that the system can help to maintain the quality of perishable foods stored in a closed storage area as well as giving it longer shelf life.
Keywords: Mobile Application, IoT, Supply Chain Management, Perishable Food, Food Shelf Life.
I. INTRODUCTION
Food is an essential and indispensable basic need for every human to live.
Handled irresponsibly, food can be a scarce commodity even when produced in high amounts and this can lead to severe hunger and malnutrition in some parts of the world. According to the Food and Agriculture Organization (FAO) Report 2019[1], it is estimated that over 2 billion people do not have regular access to safe, nutritious and enough food. Almost one-third of produced food annually is wasted in the supply chain between the producer and the consumer as a result of ineffective management in harvesting, handling, storage, packing, and transportation[2].
Currently, there is a lot of perishable food wasted along the supply chain in Bangladesh. Some of the most wasted fruits and vegetables in Bangladesh include mangos, oranges, bananas, litchis, cucumber, red amaranths, brinjals, okra, tomatoes, papaya, pineapples, and jackfruits[3]. Several technologies exist to address the loss of perishable products in Bangladesh like the usual storage
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methods such as storage at low temperature, storage in controlled atmosphere (CA) and room in a modified atmosphere (MA). However, these technologies have been introduced on a tiny scale and thus, it is still challenging for the country to reduce food loss [4].
The introduction of IoT in perishable food supply chains (FSCs) can be beneficial criteria to use to avoid food loss in closed storage areas in Bangladesh.
The Internet of Things (IoT) is expected to have grown faster than any other category of connected devices by 2020 and about 34 billion USD will be spent on the IoT devices[5].
The integration of sensors in food packaging technology has paved the way for intelligent food packaging [6]. Also, from the same study, these integrated systems can provide reliable information about the quality of the food products during their storage period. Using sensors in closed food storage areas gives consumerssufficient food quality and helps the sellers to gain increased profits. It is, therefore,essential to use automated systems to maintain avariety of foods. In that manner, the value of food will be recognized.
This study focuses on the post-harvest loss of tomatoes in Bangladesh. The regular shelf life of vegetables is 1 week. When refrigerated, plants may last for two weeks. The proposed system is intended to monitor the quality of tomatoes in a closed storage area to increase its shelf life [7]. The system uses five connected sensors to collaboratively monitor the temperatures, humidity, air quality, food color, and light intensity. The sensors monitor the surroundings and trigger cooling system, humidifier, dehumidifier, and airflow controlling devices or exhaust to maintain an optimum level of environmental factors and extend tomatoes’ shelf life. This automated system can be monitored from a mobile application by the responsible users who can also give manual commands to trigger rising targeted environmental variations. A real-time virtual monitoring report can be generated by the app to ease the user’s work. The system also alerts the user in case of suspicious or unnatural environmental changes.
II. LITERATURE REVIEW
The following section presents a literature review on food loss scenarios in Bangladesh, IoT technology, Arduino microcontrollers, and sensor networks. This literature review aims at facilitating the development of theories related to this study.
A supply chain is a set of elements and procedures that are engaged in fulfilling a customer request [8]. Food spoilage along the food supply chain is a worldwide problem related to food safety and security. According to the United Nations, one- third of the produced food is being wasted every year [9]. The food supply chain process includes many different steps like - production, processing, storage, trading, transportation, consumption, and disposal. Along the food supply chain, foods move from manufacturing to end customers. During this long process, wastage cannot be avoided due to several factors such as environmental, food perishability, improper packaging, lack of proper storage systems, inaccurate processing systems, and inappropriate transport systems. Food wastage occurs both in developed and developing countries. In developed countries, most of the food wastage occurs amidst the retailer and consumer levels.
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On the other hand, in developing countries, this issue is more evident in the post-harvest, storage and processing level [10]. In developing countries like India and Bangladesh, food wastage is accelerating due to a lack of proper knowledge, infrastructure, and inadequate monitoring systems. More than 70% of Bangladesh’s total generated municipal solid waste comes from food and vegetable [11]. From an observation of a study [10], Bangladesh’s highest per- capital food waste is generated from two major cities, Dhaka (the capital) and Chittagong (the second largest city and urban area). To reduce the severe rate of food loss, a smart monitoring system along the food supply chain can be a suitable solution.
Tomato is one of the most highly perishable vegetables in Bangladesh. The soft body texture and short potential storage life (less than 2 weeks) make this highly nutritious food item more difficult to handle along the supply chain. From a study, it is found that 32.9% of total produced tomatoes are being wasted in postharvest stages [3]. From the same survey, the estimated economic loss for drained tomatoes based on harvest price is 60.46 (7,132,568.98 USD) crores Bangladeshi taka and based on the retail price is 78.00 crores Bangladeshi taka (9,201,792.60 USD) [3].
In recent years, the development of mobile devices has shown some explosive evolutions. The technology is getting more popular due to rapid growth, affordable price, high performance, mobility, and easy usability. The mobile platform is benefitting widely in various sectors of human activity. Over the last few years, the Internet of Things (IoT) has become an increasingly growing topic of conversation in the field of technological development. As the number of mobile and different devices connected to the internet is growing, the IoT concept has emerged to utilise the full potential of these widely available hardware and the internet. The concept refers to combine physical and digital components to create new connected devices. Currently, the most popular application sectors are – home automation, wearable device, smart city[12], smart grid, industrial internet, connected car, connected health, precision agriculture[13], and intelligent supply chain management [14]. A review study [15]summarised the supporting technologies of Internet of Things such as Radio Frequency Identification (RFID), Internet Protocol (IP), Electronic Product Code (EPC), Barcode, Wireless Fidelity (Wi-Fi), Bluetooth, ZigBee, Near Field Communication (NFC), Wireless Sensor Networks (WSN), Artificial Intelligence (AI), Sensor Networks etc.
Arduino is one of the most potent open-source hardware in the recent era.
Arduino is a hardware and software company that makes microcontroller-based development boards. These boards are programmable with open-source software.
Arduino boards can read and write analog and digital input-output. It can be used in various IoT projects, electronics, and robotics projects, etc. The basic board is named Arduino UNO which is grounded on the ATmega328[16]. The open-source license, easy usability, cross-platform, availability and large community make the platform much popular among the students, hobbyists, artists, programmers, and professionals [17].
Sensors are sensing devices, modules, machines or subsystems that can detect and monitor various environmental parameters such as temperature, humidity, location, gas, vibration, motion, light, and sound. Multiple sensors in a system that actively share information and interact with each other form a wireless sensor
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network (WSN). The wireless sensor network can collect the environmental data and send it to the server. While sensors sense the ecological parameters, their actuators can perform various actions that can affect the environment by emitting sound, light or radio waves. Because of this capability of the sensors, a human can interact with them[18].
III. PROPOSED METHOD
Figure 1. Existing tomato supply chain in Bangladesh
Figure 1 shows the current stages of the tomato supply chain in Bangladesh. In Bangladesh, food products follow a long market channel. The current typical phases of a vegetable supply chain in Bangladesh are – farmers, collectors, wholesalers, retailers, and consumers. The farmers are the first stage of the supply chain. Farmers produce vegetables (in our case -Tomatoes). The collectors (locally known as Faria) collects the tomatoes from the farmers and sell them in the local market in a short volume. As their capital is low, their business is also limited in range. The next stage of the collectors are wholesalers (locally known as Bepari and Arathdar). They both are professional traders and sale tomatoes in large quantities. Beparies collect vegetables from farmers or Farias. Arathdars buy vegetables from the Beparies and they handle more substantial amounts of the product than Beparies. The retailers are the last link before the tomatoes reach to the consumers. The typical retailers are individual hawkers, local markets and supermarkets.
Most cases, usual local market retailers or the hawkers in Bangladesh does not use specific storage area to store the food products. In the local market, individual retailers may have their own small space to sell the products, or sometimes they gather in the market area to sell the product without any fixed specific land position. But recently, the supermarkets and chain shops are getting popularity among the customers for an easy and hassle-free shopping experience. For increasing demand, the super-market and the chain shops have their supply chain and functionally closed system storage capacity to store the products. In this study, our focus is on the supermarkets and chain shops rather than the other retailers because of the availability of closed system storage facilities. Figure 2 shows the application area of our smart monitoring system in the tomato supply chain in Bangladesh.
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Figure 2. Application Area of the Proposed Smart Monitoring System in Tomato Supply Chain
Figure 3 describes an overview of our proposed smart monitoring system. It shows the connection between the system, network, and user. The temperature, humidity, light, and gas sensors are installed in the closed system storage area.
The sensors compatible with Arduino Uno and with the microcontroller itself, we use a WiFi module to send the data to the cloud. To reduce the complexity of making a new and customised mobile application, here we use the Blynk IoT platform. Blynk is a popular platform to control Arduino or similar microcontrollers over the internet by using Android or iOS-based mobile applications [19]. The app allows the user to build a graphic interface to monitor sensor data and control them remotely. The uses can also analyse the data through the application. This platform is well enough to fulfill our proposed system’s requirements.
Figure 3.Proposed Smart Monitoring System
IV. RESULT AND DISCUSSION
In Figure 4, there is an elaborated inner view of the closed system storage area mentioned in Figure 3. Figure 4 is showing the positioning layout of all sensors in
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the food storage area. The location of each sensor is shown in the diagram. The temperature and humidity sensors are placed in the top-middle of the food storage area. The light sensor is placed in the food storage area to ease the detection of light changes. The light intensity can affect the quality of the tomatoes [20]. The light sensor helps to maintain light to the desired level. The color sensor is placed in the food storage part, where plastic trays are filled with tomatoes. The color sensor uses a linear slider to see the color of all the vegetables in the plastic bins all over the storage area. The gas sensors are installed to detects the appearance of gases in the atmosphere.
Figure 4. Design and Layouts of Sensor Placement in a Closed System Storage Area
In this system, we used various sensors to monitor the internal environment of the closed storage area and the quality of tomatoes. These sensors are compatible with the Arduino microcontroller. The reason behind choosing an Arduino based smart system is because it is widely available, cost-effective and easy to implement.
The Microcontroller: In our system, we used a basic model of the microcontroller – Arduino UNO. This model of Arduino can read and write both analog and digital signals. It is used to read data from the sensors and then based on the data the microcontroller sends the message to the corresponding environment controlling devices and alert system.
Wi-Fi Module (ESP8266EX): The ESP8266EX is a low-powered, cheap and highly integrated microchip that allows a microcontroller to connect with the Wi- Fi network [21]. In this study, we used this Wi-Fi module to connect the system with the cloud so that a user can monitor the information through a wireless network.
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Temperature and Humidity Sensor: The DHT-11 sensor is used to measure both temperature and humidity. It can measure the temperature from 0 to 50 ºC +/- 2 ºC and the humidity 20 to 90% +/-5%. The operating voltage of this sensor is 3 – 5.5 V DC and required a current supply of 0.5 – 2.5 mA. The sensor contains a microchip which reads the analog data from the environment and then does an analog to digital conversion to spit out the temperature and humidity information as digital signal output.
Light Sensor (Light Dependent Resistor - LDR): A light dependent resistor or LDR is used to detect the intensity of light or darkness. This tiny component has a changeable resistance. When high-intensity light falls upon the resistor, a higher voltage can pass through it (low resistance). When it is a dark or low intensity of light, the resistance of the LDR gets higher, which allows lower voltage to pass through it [22]. The signals derived from an LDR can be used to turn a light on or off.
Gas Sensor: The gas sensors are used to detect a specific type of gases. There are various types of gas sensors available that are compatible with the Arduino micro-controller. In this study, we used MQ-3 and MQ-135 gas sensor models.
The MQ-3 sensor can detect alcohol, ethanol, smoke, and ethylene [23]. Ethylene (C2H4) gas accelerates the ripening process of fruits [24]. Again, if the air quality is bad enough, it is possible to create a suitable environment to grow bacteria and the microorganisms among the tomatoes. The MQ-135 sensor can monitor air quality (CO, Ammonia, Benzene, Alcohol, smoke).
Color Sensor: In this study, we used the TCS-3200 color sensor. This sensor detects the light intensity reflected from an object. Then it combines the light intensity with wavelengths and represents color data. The received data can get in RGB or HSL value [25].
Blynk: Blynk is a popular platform for various IoT projects [19], [26], [27].
The platform allows Arduino or Raspberry Pi based projects to the internet with a WiFi module like ESP8266 [19], [24]. Blynk provides an iOS and Android platform compatible mobile application which allows the users to drag and drop necessary widgets to create a customised graphical interface based on their needs.
The application stores the information derived from the sensors in a database.
Users can monitor the real-time status of the sensor data through the application.
As the tomato flavor and quality affects by the temperature [28], the DHT-11 sensor in our system monitors the real-time temperature of the surroundings.
Bangladesh has a subtropical monsoon climate. In summer, the temperature is 30 to 40 ºC. In winter, it is 10 to 15 ºC. If the temperature is too high for the tomato quality, the system will send a signal to the temperature controller and turn it on which will keep the temperature at an optimum level for the longer food shelf life for the tomatoes.
Humidity is also a major environmental factor that affects the shelf-life of tomatoes [29]. The same DHT-11 sensor measures the humidity. If the moisture in the air is too low for the vegetables, then our system passes a signal to the humidifier to increase the humidity. Again, if the sensors detect high humidity, the system gives a message to operate the dehumidifier to low down the moisture and keep it at an optimum level suitable for the tomatoes in the storage.
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Respectively, the MQ-3 and MQ-135 gas sensors detect the Ethylene (C2H4) and air quality. If there is any Ethylene gas in the storage or the air quality is not pure enough then the system turns on the exhaust fans to pump out the polluted air from the room and make a fresh air flow into the storage.
Finally, the light sensors detect the light intensity in the storage. The excessive or low heat of light affects the quality of the tomatoes [20]. According to the data from the light sensors, the system will control the intensity of the lights in the closed storage area and keep it at an optimum level best suitable for the tomatoes.
As the proposed system is automated, the user can monitor the condition of the food quickly. Generally, for a person, it is not possible to sense all the environmental factors precisely due to human error. So, without a digital system, it is impossible to get an accurate understanding of the environmental factors necessary for the foods to keep fresh. The automated system can solve this issue.
Again, for a human, it is difficult to monitor the whole storage area and the foods in a short time. The smart monitoring system can relay real-time information about the food and environmental parameters. This feature makes the monitoring process faster than the conventional monitoring system. The cloud monitoring system via mobile application also significantly increases the mobility of the monitoring process.
V. SIGNIFICANCE OF THE STUDY
The outcome of this study will be able to bring down the waste of perishable foods in the supply chain. The proper application of the proposed system design will increase the mobility of monitoring among the retailers. The system will make the monitoring process faster and more comfortable with less effort. The same system architecture can be applied to monitor not only tomatoes but also other perishable food products with different sets of instructions. It is expected that the full application of the system will be able to reduce the food loss by approximately 20-25% significantly.And increase the shelf life from the usual three days to extended seven days in the supply chain and deliver more fresh food products to the customers.
VI. CONCLUSION
Wastage of perishable food items is an ongoing problem for any country. In developing countries, food loss happens at a severe rate before reaching consumers. Most of the food loss occurs just because of inadequate monitoring systems. In this study, we aimed to design and propose such a smart monitoring system that can reduce the loss of perishable food items in the supply chain process. As the supply chain itself is a long process, we focused on the retailers - the last stage before the consumer level in the food supply chain. The application field of the smart monitoring system is a closed system storage facility that is available at the supermarkets. The system uses various sensors controlled by a microcontroller to collect environmental data like temperature, humidity, light and air quality. According to the system data, the system can determine which environment controller (light, exhaust fans, humidifier, dehumidifier, and temperature controller) should run or not to run to keep the environmental parameters at an optimum level best suitable for the stored perishable food. Uses of a WiFi module allow the system to connect with the cloud through the internet
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and pass the data to the server. A mobile application enables users to monitor real- time information about the internal environment of the closed system storage area.
Users also can control the environmental controllers through the mobile app.
Researchers expect that the proper application of the smart monitoring system can reduce the loss of perishable food products in the supply chain at a noticeable amount. It can also make the monitoring process faster and easier.
Acknowledgments
We want to thank UniversitasAtma Jaya Yogyakarta, department of Magister TeknikInformatika, International Affairs office, The Kemitraan Negara Berkembang (KNB) scholarship program and the government of Indonesia for supporting this work. We also thank our anonymous reviewers; whose fair and thorough feed-back greatly improved this paper.
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Authors
Arefin Islam Sourav is a student in the Department of Informatics Engineering at UniversitasAtma Jaya Yogyakarta, Indonesia. His research interests are the Internet of Things (IoT), E-Learning, E-Commerce and Management Information System (MIS).
Ninyikiriza Deborah Lynn is a student in the Department of Informatics Engineering at Universitas Atma Jaya Yogyakarta, Indonesia. His research interests are the Mobile Application, Computer Networks, and IoT.
Suyoto is a Professor in the Department of Informatics Engineering at Universitas Atma Jaya Yogyakarta, Indonesia.
He has more than eighteen years of teaching experience. He received his PhD in 2000 from the National University of Malaysia, Malaysia. His research interests are multimedia, computer graphics, visualisation, mobile application, and artificial intelligence.
