Anurag Mandalika

Louisiana is the northernmost sugarcane planting region of the world. The state also has the shortest growing season of nine to 12 months and the shortest processing season of three to four months. With a total value of $3 billion, the industry is composed of half a million acres of farms, 11 raw sugar factories and two sugar refineries.

Sugarcane used to be planted extensively in the lower parishes, but its cultivation has also steadily been moving north and west thanks to the profitability of the crop and newer varieties bred for cold tolerance. Growers harvest the cane and sell this to the factories, which make payments based on both the quantity and quality of the sugarcane received. The factories convert the sugarcane into raw sugar in what is essentially a race against time. Because the sucrose in the stalk can begin to degrade as soon as it is harvested, the factories strive to convert this into a product that has longer shelf life: raw sugar. Nearly all the sugarcane grown and harvested in the state is processed by the 11 factories in the span of 12 to 16 weeks — not a small feat by any means. The goal of the factories is to finish processing before devastating freezes, which historically have occurred primarily after the beginning of January but do occur beforehand as well. The finished raw sugar is sold to the sugar refineries, which convert it into white sugar and other food-grade sugars that can be commercially purchased. The refineries pay the factories for the raw sugar based on the quantity as well as the quality.

Some of the obstacles that the industry faces today include workforce shortages and concerns about cane quality and consistency, which, in particular, is impacted by crop and weather-derived impurities. These concerns necessitate the push toward automation. AgCenter researchers have been working closely with stakeholders in Louisiana raw sugar factories to assist in this transition.

Long careers are characteristic of the sugarcane industry, as our research shows. This means that the workforce is aging and is not being supplanted by younger workers at an adequate pace. This challenge, expected to worsen over time, has prompted the industry to explore automation of factories to overcome the workforce issues facing them today, among other possible solutions. To enable effective and helpful integration of sensor networks and automation into the sugarcane industry, it was important to gauge stakeholder perspectives on needs, barriers and interest in automation options available. A survey conducted among Louisiana’s raw sugar factories delivered 39 respondents whose answers helped facilitate this inquiry.

Some of the barriers toward the incorporation of sensors in factories were identified as cost and training, followed by questions of reliability and operational logistics. Indeed, the experience of sugar industry researchers has shown that the cost of new sensors is often hard to justify with unproven technology, and the calibration of new instrumentation in factories can be complicated and challenging. Successful integration of sensors into the industry is likely going to require years of testing and development to move toward automation.

Overcoming some of the barriers to integration of sensors will require the collaborative efforts of factory engineers and operators, scientists, instrument technical engineers and sales personnel with relevant knowledge about the industry so that appropriate technologies are recommended.

Currently, several unit operations in the raw sugar factory are manually controlled by operators who use their vast experience in the industry. Most of the workforce employed during the processing season is composed of migrant workers, primarily from South and Central America, along with West Africa. These operators bring a great deal of skill to the industry, and their work ethic reflects their years of experience. For example, pan boilers in charge of crystallizing sucrose in vacuum pans are adept at qualitatively assessing the quality of the syrup or massecuite — evaporated sugarcane juice that contains sucrose — and they can determine the exact point at which they should seed the mother liquor, which is done by adding fine crystals of sucrose to begin the nucleation and crystallization process where sugar crystals begin to grow out of the solution. Our work in integrating sensors involved measuring relevant parameters that can better control and automate crystallization, collecting long-term data, and studying the size and shape of sucrose crystals in real-time using an integrated pan microscope installed in the factory to monitor the crystals as they grow.

Much of the information currently generated in raw sugar factories is composed of manufacturing reports in PDF format and tabulated analytical data from the laboratory in the form of spreadsheets. It is evident that charts are also currently in use among some engineers and supervisors, and these are likely created from spreadsheet data. An Audubon Sugar Institute research group, in collaboration with researchers at the U.S. Department of Agriculture Southern Regional Research Center, has been working on innovating this information generation process by creating a data-visualization application called Greaux Sucrose that enables real-time trends and correlations of variables of interest to the factories and can be accessed via a tablet or smartphone. Multiple raw sugar factories are being recruited to advise on useful features to incorporate into the app and share their data with researchers, which will be hosted with data security ensured on AgCenter information technology resources. The ability to instantly create plots and correlations using data already collected at the factory will allow supervisors and managers visualization that can convey historical information.

To ensure that automation in Louisiana’s sugarcane industry (and in agriculture) is predicated by fairness and equity, we have convened a group of LSU AgCenter and LSU researchers and graduate students to investigate the ethics of artificial intelligence and automation in digital agriculture. This year-long project, in collaboration with the LSU Center for Collaborative Knowledge and the LSU Ethics Institute, allows faculty from diverse fields, such as agricultural economics, philosophy, business, engineering, experimental statistics, geography and anthropology, leadership and human resource development, etc., to collaborate and create frameworks, policy recommendations, and peer-reviewed science that allows for equitable integration of AI and automation into agriculture in Louisiana.

In collaboration with the raw sugar factories in Louisiana, our research is pushing the boundaries in raw sugar processing through the incorporation of sensor networks, real-time data analytics and predictive modeling to usher in advanced manufacturing capabilities for the sugarcane industry.

Anurag Mandalika was an assistant professor at the LSU AgCenter Audubon Sugar Institute. He currently works as assistant professor of research at the Center for Energy Studies at LSU.

This article appeared in the summer 2023 edition of Louisiana Agriculture magazine.

Sugarcane farmers deliver cane to the cane yard at a sugar factory. Photo by Randy LaBauve

Anurag Mandalika works in a sugar factory monitoring the growth of crystals on a magnifying glass during the crystallization process. Photo by Randy LaBauve