Sugar cane is a versatile and fascinating plant that has been cultivated for thousands of years. From its origins in India and Southeast Asia, it has spread across the world and become a staple crop in many tropical and subtropical regions.
But what exactly is sugar cane used for? The answer might surprise you. From sweeteners to biofuels, rum to furniture, sugar cane has a wide range of applications that make it an important part of our daily lives.
In this article, we’ll explore the many uses of sugar cane and discover why this humble plant is so valuable to us all. So sit back, grab a sugary snack, and let’s dive into the world of sugar cane!
How Is Sugar Cane Used?
Sugar cane is primarily grown for its juice, which is processed into sugar. In fact, about three-quarters of the world’s sugar comes from sugarcane. This sugar is used to sweeten a wide variety of foods and beverages, including bread, canned fruits and vegetables, cakes, candies, cereal, ice cream, and more.
But sugar isn’t the only thing that can be extracted from sugar cane. The stalks of the plant can also be used to make molasses, syrup, and jaggery. In some countries, raw sugarcane stalks are even chewed on as a sweet snack.
In addition to its use as a sweetener, sugar cane can also be used to make alcoholic beverages like rum and cachaça. The ethanol produced from sugarcane can also be used as a biofuel for transportation and as an alternative to petroleum in the production of plastic.
But the uses of sugar cane don’t stop there. The pulp and stalks of the plant can be used to make furniture, cardboard, and paper products. And in some developing countries, the juice is extracted by running the cane through small mills for use in cooking and baking.
The History And Cultivation Of Sugar Cane
Sugar cane has a long and fascinating history, with the first indications of its domestication dating back to around 8,000 BCE. While chewing on sugar cane for its sweet taste was likely done in prehistoric times, it wasn’t until much later that sugar cane became a global crop.
Sugar cane originated in New Guinea, where it has been grown for thousands of years. From there, it gradually spread across human migration routes to Southeast Asia, India, and the Pacific. It is thought to have hybridized with wild sugar cane relatives of India and China to produce the commercial sugar cane we know today.
The cultivation and processing of sugar cane has come a long way since its early days. Sugar in its crystallized form has a long history and was even found in medicinal records of both Roman and Greek civilizations. Typically, sugar was used to treat indigestion and stomach ailments, and was also used in wound healing.
Today, sugarcane is the world’s largest crop by production quantity, totaling 1.9 billion tonnes in 2020, with Brazil accounting for 40% of the world total. Sugarcane accounts for 79% of sugar produced globally (most of the rest is made from sugar beets). All sugarcane species can interbreed, and the major commercial cultivars are complex hybrids.
As prices of petroleum rise, there is a growing market for ethanol from sugarcane. However, sugarcane is a water-intensive crop that remains in the soil all year long. As one of the world’s thirstiest crops, sugarcane has a significant impact on many environmentally sensitive regions, like the Mekong Delta and the Atlantic Forest.
Historic planting of sugarcane around the world has also led to significant impacts on biodiversity. The need for sugar crop laborers became a major driver of large migrations, with some people voluntarily accepting indentured servitude and others forcibly imported as slaves.
Managing social and environmental risks is important for sugarcane growers, processors, and food companies due to regulatory pressures as well as shareholder and consumer expectations for sustainably produced goods. Despite these challenges, sugar cane remains an important crop with a fascinating history and diverse range of uses.
Sugar Cane As A Sweetener: From Table Sugar To Molasses
Sugar cane is a versatile crop that can be processed into a variety of sweeteners, each with their own unique flavor and characteristics. The first step in the process is harvesting the cane, which is then cut and crushed to extract the juice. This juice is then clarified, evaporated, and crystallized to produce raw sugar.
Raw sugar can then be further processed into different types of sweeteners. Unrefined cane sugars, such as muscovado, piloncillo, jaggery, sucanat, and traditional cane molasses, contain 8 to 14 percent molasses and are often used for their distinct flavors in baking and cooking recipes. Molasses is also a principal ingredient in the distillation of rum and is used in a few beer styles like stouts and porters.
Raw cane sugars contain 2 to 3 percent molasses and include products like demerara, turbinado, and evaporated or dried cane juice. These sugars are less refined than granulated sugar and have a coarser texture and a distinct flavor that can enhance baked goods and cocktails.
Refined cane sugar includes granulated sugar, confectioners’ sugar, decorators’ sugar, and bakers’ sugar. These sugars have had all impurities removed through a refining process that renders them pure crystallized sucrose. Granulated white table sugar is the most common form of refined cane sugar and is used in a wide variety of foods and beverages.
It’s important to note that while refined white table sugar can come from either sugarcane or sugar beets, unrefined cane sugars and molasses are typically made exclusively from sugarcane. Molasses comes in a variety of levels of sweetness, from the sweet and moderate flavor of confectionery/all-purpose molasses to the strong-flavored blackstrap molasses.
The Role Of Sugar Cane In The Production Of Alcoholic Beverages
Sugar cane plays a crucial role in the production of many alcoholic beverages, including rum and cachaça. The first versions of rum were made from molasses, a by-product of refining sugar cane into sugar. However, some distilleries began distilling sugar cane wine, known as rhum agricole or cane juice rum, in the late 19th century.
The process of making alcohol from sugar cane involves fermenting and distilling the juice of the plant. Sugar cane juice is extracted from the stems and used for ethanol production by fermentation followed by distillation of sucrose or molasses. The juice is first cleaned in a dry cleaning system, which removes 70% of the dirt before entering the mills. Here, the sugar cane culms are processed and juice and bagasse obtained. Mills can typically be 97.5% efficient.
Phosphoric acid is added to the sugar cane juice and heated to 70°C, lime is added and the limed juice is further heated to 105°C. The juice is degassed and a flocculent polymer added to remove insoluble impurities. The decanted juice is filtered and the clarified juice concentrated in multiple evaporators. The final juice is made up of clarified and concentrated juice and contains about 22 wt % sucrose. It is sterilized prior to fermentation by heating to 130°C, cooled and fed to the fermentation reactor along with yeast.
Fermentation is carried out at 28°C, and the ethanol content of the solution can reach approximately 10.5% by mass of ethanol (13° Gay-Lussac level), which is an alcohol concentration of about 100 g·L−1. In order to achieve this high ethanol content, batch fermentation must be conducted for about 15 hours. The yeast cells are recovered by centrifugation and recycled to the fermentation reactor.
The alcoholic solution produced during fermentation is purified by a series of distillation and rectification columns resulting in hydrous bioethanol production (93 wt % ethanol). Anhydrous ethanol (99.5 wt % ethanol) is produced by extractive distillation using monoethyleneglycol.
Sugar cane alcohol can also be used to produce other distilled spirits such as vodka, bitters, and liqueurs. Its versatility makes it an ideal base spirit for industrial alcohol production, catering to different alcohol types and tastes from around the world. Its uses even extend beyond alcohol production, as it can function as a preservative, aid in vinegar production, and many other food applications.
However, it’s important to note that sugar mills produce wastewater, emissions, and solid waste that can have negative impacts on the environment. The massive quantities of plant matter washed from mills can decompose in freshwater bodies, leading to fish kills, while mills release flue gases, soot, ash, ammonia, and other substances during processing. It’s crucial for sugar cane producers to implement sustainable practices to minimize their environmental impact.
Sugar Cane As A Renewable Energy Source: Biofuels And Beyond
Sugar cane is also being increasingly used as a renewable energy source. Its by-products, including bagasse (the fibrous residue left after juice extraction) and vinasse (the liquid residue from ethanol distillation), can be converted into biofuels like ethanol and biogas. These biofuels have lower carbon emissions than traditional fossil fuels, making them a more sustainable option for transportation and energy production.
Moreover, the residual biomass fractions of sugarcane, such as sugarcane trash or straw, ashes from bagasse combustion, and filter cake from juice clarification, present unexploited potentials for further product portfolio diversification. Innovative cascading processes using these residual biomass fractions could significantly reduce final disposal costs, improve the energy output, reduce greenhouse gas emissions, and extend the product portfolio of sugarcane mills.
The USDA has partnered with the University of Hawaii and Hawaiian Commercial & Sugar Company to develop new ways to grow and use sugarcane as a source of biomass. Sugarcane has the greatest near-term potential as a biomass feedstock for producing biofuels in Hawaii. It is perennial and non-invasive, already grown in Hawaii for over a hundred years, and has room to improve existing yields by using newer varieties and harvesting other parts of the plant.
The Navy is also interested in using biofuels in its fleet to “green” its large fleet of ships stationed in Hawaii. The USDA, the Department of the Navy, the University of Hawaii, and Hawaiian Commercial & Sugar are now working together on this project. With its potential to produce both cellulosic biomass that can be converted into sugars as well as the sugar itself, sugarcane yields more energy per acre than other existing crops. This makes it a promising renewable energy source for the future.
The Surprising Uses Of Sugar Cane In Furniture And Construction
Sugar cane is a versatile plant that can be used in a variety of applications beyond just food and drink. One surprising use of sugar cane is in the production of furniture and construction materials.
The solid stalks of sugar cane can be used as a natural and sustainable alternative to wood in furniture construction. The cane is harvested, dried, and then treated to prevent insect infestation and rot. The resulting material is strong, durable, and has a unique texture that adds character to furniture pieces.
In addition to furniture, sugar cane can also be used in construction materials such as panels, boards, and roofing. The fibers from the cane stalks are mixed with resins and compressed to create a strong and lightweight material that is resistant to moisture and fire.
One example of this use of sugar cane is in the construction of the Green School in Bali, Indonesia. The school was built entirely from bamboo and sugar cane, showcasing the versatility and sustainability of these natural materials.
The Future Of Sugar Cane: Sustainable Farming And Innovation
As the world becomes more conscious of the need for sustainable development, the sugar industry is also looking towards sustainable farming and innovation to ensure its viability. Sustainable development is defined as meeting the needs of the present without compromising the ability of future generations to meet their own needs. To achieve this, it is important to take into consideration social, environmental, and economic issues, also known as the triple bottom line.
The sugar industry has been associated with sustainability issues, including the impact of sugar mills on the environment. However, there have been efforts to improve sustainability in sugar cane cultivation. For example, in Brazil, sugar cane cultivation has transitioned from being associated with degrading working conditions, low productivity, and high pollution to being one of the best examples of sustainable development in the region.
Innovation is a key element in enhancing sustainability, and the sugar industry can tackle major sustainability issues through innovation-centric approaches. The industry can utilize technological innovations such as bio-energy, green harvest and sustainable uses of trash, C-sequestration, climate resilient varieties, agriculture 4.0 and agro-technologies, bio-intensive crop production and protection technologies, water management in field and process, zero pollution discharge, recycling of steam, valorization of biomass, cellulose, lignin, molasses, PMC, vinasse, CO2, cellulosic ethanol, H-fuel cell technology, bio-fuels and aviation fuel, organic and specialty sugars, green fertilizer, and bio-degradable plastic and bio-based products of pharmaceutical, medicinal, and industrial importance.
Sustainable farming practices are also being implemented by sugar cane farmers. These include adjusting the space between sugar cane plants to reduce crop losses and better controlling truck traffic. Techniques for maintaining loosened soil and using GPS systems for controlling large agricultural machines are also being deployed. Water use is being made more efficient by farmers growing legumes when not growing sugar cane to cut pesticide use and improve soil quality. Soil moisture is being better retained by leaving cane leaves on the ground instead of burning them; an action which also reduces global warming.
The future of sugar cane lies in sustainable farming practices and innovation. The development of modern bio-refineries using sugarcane as feedstock allows for innovative combinations of value-added products and services from both agricultural and industrial sources to ensure efficient and effective use of sugarcane resources in support of sustainable development pathways. With sustainable practices in place and continued innovation in the industry’s processes and products, sugar cane can continue to be a valuable resource for future generations.
