The e-aphrom is Winegrid’s latest solution for monitoring the second fermentation stage in sparkling wines produced via the Champenoise method. This article presents the e-aphrom’s working principle and interface and provides an example of the device’s application in a real scenario. This technology represents a step forward towards the future of winemaking.
Introduction
With the wine industry increasingly focusing on efficient monitoring systems, innovative technologies have emerged. These advancements, driven by the need for production optimisation, quality control and safety, have paved the way for the application of IoT (Internet of Things) monitoring systems. These systems, powered by a network of diverse sensors, gather, analyse and store crucial data, providing invaluable assistance to winemakers at various stages of the winemaking process.1
Recently, some companies have been developing IoT monitoring systems with sensors designed to measure pressure, liquid level and density, among others.2 Winegrid’s Research and Development team comprises several specialists working on AI-based platforms that help winemakers monitor different real-time parameters. Two of its more recent sensors aimed at sparkling wine production are the e-aphrom and e-charmat. These present remote solutions in real-time that allow pressure monitoring during the secondary fermentation.
The secondary fermentation creates bubbles in sparkling wine. The chemical reaction transforms sugar into alcohol and carbon dioxide.3 The two more popular methods include the Charmat and the traditional Champenoise methods. The main difference between the two approaches is the stage at which the secondary fermentation takes place. In the Champenoise method, after adding the sugar and yeast, the wine is transferred to a bottle and sealed to imprison the CO2. Some winemakers point out that this methodology has the advantages related to a longer time in the bottle, such as adding more complexity to the wine due to a higher surface area for wine and yeast exchange and allowing a more gradual process of stirring than centrifugation methods. In the Charmat method, secondary fermentation occurs in a large, sealed and pressurised tank. Only after the end of the process is the wine transferred to a bottle. This is less time-consuming and an easily scalable process.4
Several parameters are important to monitor. Increased pressure is a strong indicator of the start of secondary fermentation. The e-aphrom is an online system that acquires pressure and temperature in real-time. This solution helps monitor secondary fermentation by storing the data in a cloud platform and displaying it on a dashboard. It allows data to be compared, previous values to be revisited, and the system to interact with it via manual information insertion. This dashboard can send notifications in case any threshold is crossed.
Technical features of the e-aphrom sensor
Sensor characteristics
The e-aphrom’s pressure monitoring sensing mechanism is based on piezoresistive behaviour. The sensing layer is made of conductive material that changes resistance when stretched. This change in resistance is detected, exhibiting an output voltage proportional to the stimulus. The device also contains a reference input, so the final pressure is presented relative to the atmospheric pressure (gauge sensor). Figure 1 illustrates the described sensing principle.
FIGURE 1. Working principle of the pressure sensor.
The sensor has an aluminium probe with a natural rubber seal. This probe is in contact with the inside of the bottle and measures the pressure and temperature in its gaseous space. Figure 2 shows the dimensions of the device.
FIGURE 2. Dimensions of the e-aphrom.
The sensor is powered with three AA batteries of 1.5 V, and it is screwed in the bottlenecks. The standard designed dimensions are prepared for 29 mm diameter bottlenecks. However, they can be designed to adapt to other values if needed. The measurement parameter specifications are presented in Table 1.
TABLE 1. Parameter specifications of the e-aphrom.
The cleaning procedures are simple to apply. They only require the application of alcohol and water to the adaptor parts (including the orifice).
Installation requirements
Before installation, it is essential to guarantee that the batteries and the antenna are placed correctly, and that the winery has an internet connection. The sensor has an adaptor that will be used for installation. The device is placed on the top of the bottle, putting the rubber membrane in contact with the opening. The adaptor is then screwed firmly onto the bottle to prevent leakage. Figure 3 illustrates the process of installation.
FIGURE 3. Placement of the e-aphrom in the bottle.
Every e-aphrom communicates wirelessly with a smartbox. This equipment is the gateway that pairs more than one sensor with the online platform. Another important feature of the smartbox is its ability to store data in case of an internet failure.
After the correct sensor installation, the user can interact with the dashboard and visualise the data.
Data communication and dashboard
The data acquired in real-time is sent wirelessly through the smartbox (the gateway) and then sent via an internet connection to a cloud platform, where it will be stored and processed (applying, for example, unit conversion algorithms). LoRa WAN and Wi-Fi communication protocols are used for, respectively, long-range (line of sight up to 2 km) and close-range (line of sight up to 50 m) applications. Figure 4 presents the general overview of the IoT schematics.
FIGURE 4. IoT schematic.
The stored data can be accessed anywhere and at any time, allowing for the comparison of historical data. All registered sensors can be displayed simultaneously, allowing users to add labels and individual information manually.
Figure 5 displays other possibilities that the dashboard presents to the user. Some more relevant examples include comparing data from different sensors, adding notes, exporting data and analysing technical information like the battery’s charge status.
FIGURE 5. Dashboard features.
The device can generate alarms that email users to inform them of the status of the data collected. The winemaker can set thresholds to notify important values that mark the beginning and end of the second fermentation. The alarms may also indicate the status of the sensor device pairing with a local network.
Case study
Figure 6 presents an example of actual data collected by an e-aphrom from a typical secondary fermentation process using the traditional methodology. It includes pressure and temperature measurements. In this graphic, the pressure started to increase around the 27th of March. Around the 24th of April, the increase took place slower, reaching a plateau of over seven bars around the 3rd of July. This is a strong indicator that, at the end of March, the chemical reaction corresponding to the secondary fermentation started, thus producing more carbon dioxide. Although the winemaker can assert with higher certainty, the process has ended at the end of June (or at the beginning of July). Since the e-aphrom is designed to monitor sparkling wines made via the traditional method, the period that this wine was in secondary fermentation corresponded to the expected three months.
FIGURE 6. Data acquired from the e-aphrom displaying pressure and temperature values.
The user can access the temperature values in real-time, as all changes will be recorded and exhibited on the dashboard at the same time as the pressure values are displayed. From this graphic, one can see that the temperature started to increase at the end of May until around 18°C, probably because the environmental temperature rose due to summer approaching in the northern hemisphere. This allowed the producer to apply cooling systems to decrease the temperature to approximately 14.5°C.
The winemaker could also retrieve information from separate wineries and compare the values simultaneously. Figure 7 displays this feature. The two curves were taken from two sensors placed in different bottles. The duration of the second fermentation process was approximately the same. However, slightly different pressure values were displayed, which is expected since, in the traditional methodology, the chemical reaction takes place in individual bottles, thus each one representing its own chemical system.
FIGURE 7. Data acquired from the e-aphrom displaying pressure values from separate sensors.
Conclusion
Real-time monitoring is an important technology that is increasingly in demand in winemaking. It allows for greater efficiency during the different winemaking processes, enabling preventive monitoring and a faster response to any anomaly detected. The comparison with historical values allows for improvement in the quality of the final product.
References
- Popović et al., 2021. A novel solution for counterfeit prevention in the wine industry based on IoT, smart tags, and crowd-sourced information. Internet of Things, Volume 14, p. 100375.
- -É. Pelet, M. Barton and C. Chapuis, 2019. Towards the implementation of digital through Wifi and IoT in wine tourism: Perspectives from professionals of wine and tourism. Management and Marketing of Wine Tourism Business: Theory, Practice, and Cases, pp. 207 – 236.
- Buxaderas and E. López-Tamames, 2012. Sparkling wines: Features and trends from tradition. Advances in Food and Nutrition Research, Volume 66, pp. 1 – 45.
- Ubeda, R.M. Callejón, A.M. Troncoso, A. Peña-Neira and M.L. Morales, 2016. Volatile profile characterisation of Chilean sparkling wines produced by traditional and Charmat methods via sequential stir bar sorptive extraction. Food Chemistry, Volume 207, pp. 261 – 271.
For more information, contact Lida Malandra at lida.malandra@enartis.co.za.
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