« Back
Radio Frequency Identification (RFID) in Agriculture–Food Safety and Traceability
Agro-food sector
Radio Frequency Identification (RFID) is a modern technology which is also being more and more enforced in agriculture. RFID is a technology for wireless data transfer between the reader (data collection centre) and the electronic smart label that measure
In 2012, at a trial plantation of apple-trees of the Sadjarski center Maribor (The fruit growing centre Maribor) we began to test the prototypes of the labels placed on the apple-trees, which were equipped with humidity, light and temperature sensors, and enable continual data collection in the observed measuring period. With these measurements, we wanted to find out the accuracy of the data measurement, how the labels and the sensors react to different weather conditions (rain, wind, sun, cold...), to find out the capacity of the wireless data transfer and the battery endurance. The aim of the test was to develop or propose a new selection of sensors and to determine the parameters for the development of future: dedicated tags’ ICs and sensors for different needs of prediction in agricultural branches. The data from these labels could cheapen the tracking of microclimatic conditions and alleviate the prediction of illness and pest development.

The use of labels in an orchard

In 2012, we began to test the prototypes of the labels to find out the accuracy of the data measurement, behaviour of labels in different weather conditions (rain, wind, sun, cold...), the capability of the wireless data transfer, and the battery endurance.
We are currently in the phase of testing the second generation of the prototypes on which we placed new, better light and humidity sensors, more suitable for agriculture. The right choice of sensors is always in the domain of agricultural experts, because they are the only ones who know which physical conditions influence the growth, fruitfulness and the infections in different fruit sorts or plants. The prototype of the label in Figure 2 is composed of a microchip of 7 mm2 size and 100 µm thickness (the applicative electric scheme of the label is in Figure 3), and it already has a temperature sensor built in, on which two external sensors (e.g. for humidity and light) can simultaneously be connected.

For data gathering, a battery with a life-expectancy of five years was added. Usually we use pressed battery of 0.7 mm thickness or button battery, as it was the case with our prototype model. When the label is in the electromagnetic field (EM) of the reader, the battery does not supply the labels, as this is automatically switched over to EM field supply through an aerial. The labels are hung up directly onto the trees in the plantation without prior installation of electrical power, because they have own supply through the battery; communication and data transfer into the reading machine are also carried out through EM wave motion. The advantage of the microchips is the small consumption of electrical energy which is needed for detection, storage, and data transfer.
We positioned the label prototypes onto the apple-trees so that we could always have identical conditions of data gathering in an observed measurement period. We labelled them with red ribbons so that we avoided possible mechanical injuries which could have arisen during machine work in the plantation. At preset intervals, the label recorded and saved the temperature, humidity, light intensity, and the time of the measurement data into the data storage. The data can be read from the label at any point, even if the life-expectancy of the battery has run out. The distance for data collection is large, as certain readers enable contact-free data transfer up to the distance of 100 metres. At the same time, this is the largest range that RFID technology enables without violating any national or international standards regarding the radiation power of the EM wave motion. We can also equip agricultural mechanisation (tractors) with the readers and thus take care of direct transfer of gathered data to the internet.
Use of labels in other fruit sorts

As it is known, strawberries (Fragaria) are very sensitive to high temperatures which directly influence the quality and preservation of the fruit. For now, growing, storage, and sale are left over to the trust between the grower, distribution centres, transporter, and the store on one side, and the final customer on the other. The latter is left to the subjective opinion about the quality of the strawberries, tied to the appearance and the odour of the fruit. No member in the chain has an objective proof that they have handled the fruit properly. A possible proof, recorded on the RFID label could be useful for both the supplier and the customer.
RFID Smart Labels can be used in the complete chain. First, the fruit-grower places the RFID labels onto the strawberry chests, and thus records temperature, humidity and time. Then, the information recorded on the labels, is used in the distribution centre where they found out the origin of the strawberries from the identification number, and where they need to be sent. Besides that, the label also contains the information about the usage time limit which enables that the chests with shorter time limit are sent first (Figure 4).
The information about time limit can also be used at the store where they load the chest with the shortest time limit onto the shelves. So we have less redundant products on the shelves. The RFID can also be used at the cash register instead of the linear code to calculate the final sum of the purchase. The most important advantage of tracking in strawberry growing is automatic measuring of chemical and physical parameters of transport and storage which are stored into the label, directly placed to the product being monitored (Kosta Kovačič 2011).
Blaž Germšek