Among the 3 billion people globally that live their lives in a state of dire malnutrition, 224.3 million are in India, a nation that is over 50% reliant on rice as a staple diet food — namely due to its locality and subsequently low price. In an area where rice is so readily available to even the lowest on the socioeconomic scale, it’s not surprising that people as such often have dangerously low levels of essential nutrients like iron, Vitamin A, and Protein. This house staple is simply not good enough and doesn’t suffice the massive role it plays in billions of people’s lives. How do we change that? Ultrasonic-assisted nutrient enrichment (a mouthful, I know): the process of adding nutrients to rice through ultrasonic radiowaves. Before we get into the nitty gritty of that — let’s start with the basics.
Rice 101
Rice is a staple food used in many Indian dishes. However, nutritionally, it doesn’t contain many. For example, half a cup of basmati rice, the staple rice type in Indian cuisine, doesn’t have any Vitamin A, Vitamin C, Vitamin B6, Vitamin D, potassium, magnesium, calcium, dietary fibre or iron. It contains 6g of protein, which is only 13% of the daily recommended amount. For the 50% of the Indian population that relies on rice as its primary source of nutrition, its nutrients are not enough. Globally, it provides 20% of the world’s dietary energy supply.
Rice is the seed of the grass species Oryza sativa (commonly known as Asian rice) or less commonly O. glaberrima (commonly known as African rice). Rice cultivation is well-suited to countries and regions with low labour costs and high rainfall, as it’s labour-intensive to cultivate and requires ample water. However, it can be grown practically anywhere with the use of water-controlling terrace systems. Currently, most of the world’s rice is grown in India and China, with 178.3 million tonnes and 211.9 million tonnes grown in 2020 respectively.
Rice is processed by first putting the seeds through a rice miller to remove the chaff. Once put through a miller, the end result is brown rice. The rice is then processed further until the desired rice type is achieved.
Biologically, a rice grain has four layers: the chaff (hull), the bran, the endosperm, and the germ.
The chaff is the outermost layer of rice as a seed. As mentioned earlier, the first step of processing rice so that it is ready for consumption is removing the chaff by putting it through a rice miller.
The bran is the outermost layer of the rice we eat. It’s what gives brown rice its signature colour and contains fibre, vitamins, minerals, and antioxidants. Bran is composed of 12% oil that is often extracted to form rice bran oil.
The endosperm is the middle layer of the grain, and it makes up the majority of the rice grain. This part of the grain is composed mostly of starch, which provides energy for the plant and is a source of carbohydrates for humans. To make white rice, the germ and bran are removed from the rice, leaving only the endosperm. Due to the fact that the endosperm has barely any nutrients, some companies prepare white rice by mixing in a dry mix of some vitamins that were lost throughout the milling process. However, since these vitamins are easily lost during the washing process, white rice has a low nutritional value.
The germ is the innermost layer of the grain, and it contains the plant’s embryo, which is capable of sprouting into a new plant. The germ is rich in nutrients, including vitamins, minerals, and healthy fats.
Ultrasonic Treatment
Ultrasonic treatment is a rapidly growing field that has revolutionized the way we process and manipulate materials. By utilizing high-frequency sound waves, ultrasonic treatment is capable of driving a wide range of physical and chemical processes. These sound waves operate at frequencies beyond the range of human hearing, typically between 20 kHz to 100 kHz. As a result, ultrasonic treatment is highly effective at treating materials in a non-invasive and energy-efficient manner, making it a popular choice for a variety of industrial and scientific applications. The underlying principles of ultrasonic treatment are based on the effects of high-frequency sound waves on materials. These sound waves cause physical and chemical changes in materials through a combination of cavitation and acoustic streaming.
- Acoustic cavitation is the fundamental mechanism behind the ultrasonic treatment process. The bubbles created by the sound waves collapse when they reach a certain size, releasing energy in the form of heat and shock waves. This process leads to a range of effects, including intense mixing, emulsification, particle size reduction, and sonochemical reactions.
- Acoustic streaming refers to the movement of fluid caused by the propagation of sound waves through the liquid, which can help to mix and homogenize the solution. Microjets are high-speed streams of liquid that are generated by the collapse of cavitation bubbles, which can cause mechanical disruption and agitation of the sample.
The ultrasonic bath system consists of a tank filled with a liquid medium, a transducer, and a generator. The transducer is typically made of piezoelectric materials, which convert electrical energy into mechanical vibrations, while the generator produces the electrical signals that drive the transducer. It is placed at the bottom or side of the tank and emits high-frequency sound waves into the liquid.
The probe system is another type of ultrasonic treatment device that is used for localized treatment of materials. It consists of a transducer attached to the end of a probe, which is immersed in the liquid medium. The probe system can be used for more targeted treatment of materials, such as the cleaning of surfaces or the extraction of compounds from solid materials.
The ultrasonic bath system is ideal for processing large volumes of liquid and can be used for a variety of applications, such as cleaning, mixing, and extraction. It is a versatile and efficient system that can handle large batches of materials and can operate continuously or intermittently depending on the needs of the process. Additionally, the ultrasonic bath system is easy to operate and can be used with a wide range of liquids and materials, making it a popular choice for industrial and laboratory applications.
The tech side of ultrasonic treatment involves optimizing the process parameters to achieve the desired effects on the materials being treated. These parameters include the frequency and power of the sound waves, the duration of treatment, the temperature and pH of the liquid medium, and the concentration and composition of the materials being treated. The optimization of these parameters is critical to achieving the desired results and minimizing unwanted side effects.
- Frequency: Ultrasonic treatment typically operates at frequencies between 20 kHz to 100 kHz, although some systems can operate at higher frequencies. The frequency of the ultrasonic waves affects the intensity and depth of penetration into the material being treated. Higher frequencies are generally better for more delicate materials, while lower frequencies are better for tougher materials.
- Power density: Power density is the amount of ultrasonic energy applied to a liquid medium per unit volume. Higher power density typically leads to more intense cavitation and acoustic streaming, which can result in more efficient treatment.
- Intensity: Ultrasonic intensity refers to the amount of energy per unit area per unit of time transferred by sound waves through a liquid medium. Higher intensity generally leads to more effective treatment, but it also increases the risk of damaging delicate materials.
- Time: The duration of ultrasonic treatment is an important parameter that can be adjusted to optimize treatment for specific applications. Longer treatment times generally lead to more complete treatment, but they can also increase the risk of damage to materials.
- Temperature: Temperature can also play a role in ultrasonic treatment. Higher temperatures can increase the effectiveness of the treatment, but they can also increase the risk of thermal damage to materials.
The unique ability of ultrasonic treatment to generate acoustic cavitation has led to a range of effects that have practical applications in various fields, including medicine, food processing, and environmental remediation. This is the reason we believe ultrasonic treatment has the potential to improve the nutrition in rice and we will explain how exactly it will be in the next section.
Rice x Ultrasonic Treatment
Section 1 — Overview of the process
To connect the two (finally), we go through a process known as ultrasonic-assisted nutrient enrichment. As the name suggests, the process involves adding nutrients to individual grains of rice by virtue of the ultrasonic treatment mentioned earlier, and the process has shown significant promise in increasing the nutritional value of rice– with several studies finding a highly reflected margin of increase.
To carry it out, we start with our two main elements, the water and the rice.
In a chamber separate from the main one, where the sound waves are actually emitted, water is turned into a low-concentration solution containing our desired nutrient (an example would be adding highly concentrated ferrous sulfate to the water to increase iron). By using a propellor-type system to keep the mixture in constant motion, this fairly simple solution is ready to be added to the main unit.
To note, the precise concentration of the nutrient-added solution is dependent upon a variety of factors, including the type of rice (and its subsequent structure– which affects its ability to absorb nutrients), grain size, desired nutritional increase, and more. Since an overflow of these nutrients can actually rupture the membrane of the rice grain permanently, causing damage to its texture and performance when cooked, this value is often assessed through highly specific testing and iteration.
After this solution is prepared, we bring out our money maker, the rice itself. Before entering the chamber in which the waves are emitted, the rice is in one of two forms, raw or par-soaked. More on its significance later, but the latter is often done to increase the porosity of the rice’s hull and/or bran. Generally speaking, since the process is so sensitive, to begin with, a lack of porosity is not a concern, and the rice goes in raw.
Once in the chamber, covered by our nutrient solution, we can actually turn on the ultrasonic machine to begin the process of nutrient enrichment. In order to suffice the bare minimum of this process, the ultrasonic waves are emitted at a frequency of roughly 20 kHz, an amount that is generally enough to rupture our rice grains to a desired degree. As the grains sit in there for roughly 5 to 30 minutes, the temperature of our bath is also playing an integral role. In order to optimize nutrient absorption without the possibility of cooking or damaging the rice’s innings, the temperature of the bath is kept between a range of 25 and 70 degrees Celsius. While the process of maintaining this range can be strenuous due to the variety of happenings in and around the chamber, more recent iterations of the device use a thermostatic, or temperature regulation, tank alongside equipped temperature sensors.
Section 2 — The Significance of These Steps
To better understand the deciding and manipulation of these steps, let’s take a look at what’s actually happening to the rice as we carry out this process.
When ultrasonic treatment is applied to rice or any plant cell, it causes acoustic cavitation to occur. Once the bubbles formed by the cavitation bursts, small ruptures appear on the surface of the rice cell. As this process occurs all over a grain of rice, fissures litter the entire structure, making it much more permeable without changing its outward texture or appearance (this process is also known as the loosening of the rice matrix). As is the case with most cells, permeability is basically an invitation for external substances, like our desired nutrient, to pass through the membrane of the cell and absorb into its structure. By creating and bursting bubbles in rice grains, we are able to increase the nutrient uptake of rice by up to 50%. This drastic nutrient uptake is accounted for by the capillary and sponge effect, the idea that capillary action dramatically increases in porous membranes, like seen in a sponge.
Section 3 — Understanding the Parameters Placed
Like alluded to earlier, many of the factors that play a role in ultrasonic-assisted nutrient enrichment (a mouthful, I know) are variable — and very sensitive. Due to the delicate stature of a rice grain, creating an environment conducive to this process can be a little finicky despite any available data, and is ultimately up to an individual manufacturer. As a result, we foresee anywhere from 6 months to a year of establishing our footing involving iterative testing, in which we can play with all factors involved in the process to optimize our outcome. Just to establish a framework, though, here are the main parameters involved in the process and how they’d be evaluated:
- Frequency of the ultrasonic waves: truly optimal frequency and intensity are very dependent on our chosen nutrient and its concentration in the water bath, but a general concept to bear in mind is that larger particles (or rice grains) require a lower frequency, as the longer wavelength does a better job of penetrating thicker surfaces. For reference, the baseline of 20 kHz is considered to be a lower frequency, meaning it accounts for medium to large rice grains, the ones most often consumed. This factor is probably the least subject to change, as multiple studies have concluded that, when using a 20 kHz frequency, the starches on the rice don’t sustain any damage, and that any observed is reliant on one of the other factors listed below.
- Nutrient solution concentration: the general goal of adjusting this concentration is to reach the happy medium of reaching our desired nutrient level without damaging the rice grain — causing any physical or chemical changes to the rice grain that affect its quality, texture, or nutritional value. While general ratios of solvent to solute are yet to be understood in much detail, it is widely understood that this process of nutrient enrichment requires a relatively low premix (or nutrient) to rice ratio. This is because, for lack of a better term, sonification compensates greatly for the lack of a nutrient by creating micro-fissures in the rice — which drastically increase its nutrient uptake.
- Temperature: The big thing to note here is that higher temperature results in higher rates of nutrient absorption, as heat further breaks down the rice matrix — the physical-chemical composition of the rice grain. Therefore, the desired range for our temperature generally resides on the higher end, between 25° C and 75° C, laying somewhere within the two so long as it doesn’t cook.
The Magic Maker
Section 1 — Components of the Machine
The ultrasonic device we designed (see below) is made to increase the nutrition in rice using ultrasonic waves. The device consists of several key components, including a processing vessel, transducer, generator, control panel, and safety features.
The processing vessel is a stainless steel container with a capacity of 1–5 kg of rice for pilot testing. The stainless steel container holds the rice during the treatment process and allows the ultrasonic waves to penetrate the grains, enhancing their nutrition.
The transducer is mounted at the bottom of the processing vessel and is made of a durable and corrosion-resistant material, such as titanium. Mounted at the bottom of the processing vessel, the transducer is responsible for converting electrical energy into ultrasonic waves. It operates within the frequency range of 20 kHz to 100 kHz, ensuring effective penetration of the waves into the rice.
The generator is a low-power device that powers the transducer. It can operate on a standard electrical outlet for pilot testing purposes. It supplies the necessary power to the transducer, enabling it to produce ultrasonic waves. It is designed to operate on a standard electrical outlet and provides the required energy for the treatment process.
The control panel is mounted on the side of the device and allows the operator to set the desired ultrasonic parameters, such as the frequency, power, and duration of the waves. Located on the side of the device, the control panel allows the operator to set and adjust various parameters for the ultrasonic treatment, such as the frequency, power, and duration of the waves. It provides a user-friendly interface for controlling and monitoring the treatment process. The control panel also includes an on/off switch and an emergency shut-off button for safety.
The safety features of the ultrasonic device include an automatic shut-off mechanism that activates if the processing vessel becomes overfilled or if there is a malfunction in the ultrasonic system. The device also includes a cooling system to prevent overheating and damage to the transducer and other components.
Section 2 — How it works
In operation, the operator loads the rice into the processing vessel and sets the desired ultrasonic parameters on the control panel. The generator powers the transducer, which produces ultrasonic waves that penetrate the rice and increase its nutrition. The rice is treated for a short period of time, ranging from a few minutes to an hour, depending on the desired level of nutrition. Once the treatment is complete, the operator unloads the rice from the processing vessel and prepares it for consumption or further processing.
The compact size of the ultrasonic device makes it highly suitable for pilot testing in a single village or district. Its small footprint allows it to be easily accommodated in limited spaces, such as community centers or local processing facilities. This portability is a significant advantage as it enables the device to be transported to different locations where rice production is prevalent.
The device’s safety mechanisms are crucial for ensuring the well-being of operators and preventing any potential hazards. The automatic shut-off system, activated in cases of overfilling or system malfunctions, adds an extra layer of protection. This feature not only safeguards the device but also minimizes the risk of accidents or damage to the rice being treated. Additionally, the cooling system prevents overheating, preserving the longevity and efficiency of the transducer and other components.
Considering its compact size, and safety mechanisms, the ultrasonic device can serve as an ideal tool for pilot testing initiatives. It allows for targeted trials in specific villages or districts, providing a controlled environment to evaluate the effectiveness and feasibility of rice treatment using ultrasonic technology. The insights gained from pilot testing can guide further research, process optimization, and potential scalability for larger-scale use in the future. By starting with pilot testing, the device can be refined and adapted to meet the specific needs and challenges of different communities and regions, laying the foundation for sustainable and widespread implementation of ultrasonic treatment in rice production.
Feasibility
Using ultrasonic treatment to increase the nutritional value of the rice is the optimal solution. For just over $US 13 000, an industrial, high-quality ultrasonic machine can be made. After creating partnerships with local farmers, this solution will be ideal and sustainable for years to come.
Eventually, within 5 years of implementing this solution, UltraRice would have multiple factories in India to improve the nutritional value of rice and make an impact on millions of lives.
UltraRice uses a simple and safe method to ensure that clients are getting high-quality, nutritious, and safe rice to consume.
Our mission is to ensure that one’s economic state doesn’t define their ability to access nutritious foods. We aim to ensure that by 2050, the 3 billion people globally who are malnourished become 0 people globally.
UltraRice wants to make a change and a difference in people’s lives. And it’ll all start with rice.
