Green Novel Tech or better known as GNT, is a spinoff technology firm from Kasetsart University Faculty of Agro-Industry formed to support small and medium enterprises (SMEs) in Thailand to gain access to innovative technology.
GNT has worked to adapt and localise ohmic heating technology for low-acid fluids containing particulates, which had been approved in the UK and the US in the 1990s. Currently, there are many ohmic heating facilities in Europe, Japan and South America and these facilities usually process a variety of products into fruit purees, fruit slices, sauces and curries amongst others.
Due to the high cost of this technology, GNT has successfully localised this technology through engineering redesign, local component sourcing and modular system development to make it affordable, accessible and practical for small-scale food manufacturers.
According to Associate Professor Pitiya Kamompatana, Consultant for Food Processing Innovation at GNT, “Our systems are now compact, energy efficient and can be integrated into existing production lined with minimal disruption. We also provide technical support, operator training and process validation to ensure a smooth transition and long term value to our customers.”
Liquid food products that use ohmic can achieve a superior quality product due to the process unique heating mechanism. Unlike conventional thermal processes that rely on heat transfer from outside to inside, ohmic heating uses electrical current that flows directly through the food, generating heat uniformly and rapidly throughout the product. This results in reducing processing time, minimizing thermal damage and preserving nutritional, sensory, and structural attributes of the food product.
Ohmic heating technology can also be applied to a broad spectrum of products, including high-viscosity liquid foods, fruit juices, and antioxidant-rich beverages, underscoring its versatility and industrial scalability.
Ohmic heating technology by GNT offers SMEs in Thailand an avenue to scale up their products both in terms of quality and flavor, yet at an affordable cost of production, thereby allowing them to reach out to the mass consumer market. So far, according to Dr Pitiya, GNT has worked with several food companies in Thailand to adopt its ohmic heating technology to produce Thai fruit syrups, juices and other liquid food products.
Currently, GNT offers a complete range of services from lab-scale testing services for companies that has just started to explore this technology; to OEM services for those that want to enter the market quickly, or test the market without the need to invest in equipment. In addition, GNT also offers custom-designed ohmic heating systems engineered to match client specifications.
AFBR has recently interviewed Dr Pitiya at Thaifex Anuga Asia 2025, in which GNT has a booth showcasing its ohmic technology near the Future Food Experience+ in Hall 5. The following are the full excerpts from the interview with her:
Can you tell us in more detail the new technology offered by GNT to SMEs in the production of liquid food and beverages?
Our core technology is a continuous-flow ohmic heating system, which applies electrical current to heat foods uniformly and rapidly from the inside. This makes it highly effective for processing juices, syrups, soups, sauces, and other liquid-based products. The system is designed to be compact, user-friendly, and cost-effective, making it practical for SMEs
Where was this technology originated and you mentioned that it is now made affordable for smaller companies in their production?
Ohmic heating technology for low-acid fluids containing particulates was approved in the UK and in the United States in the 1990s (Zareifard et al., 2014). Today, there are a significant number of ohmic heating facilities in Europe, Japan, Mexico, South America, and other regions (Kamonpatana et al., 2013; Yildiz-Turp et al., 2013). These facilities process a variety of products, most notably fruit slices and large fruit pieces in syrup. Commercial food products processed with ohmic heating include: Fruit and vegetable purees (e.g., tomato ready-to-serve sauces, mango puree, tomato paste), Fruit slices (e.g., diced strawberries, peaches, apricots), Large fruit pieces in syrup and Vegetable curries.
As a spinoff technology from a Thai government university—Kasetsart University (KU), Faculty of Agro-Industry—our primary objective is to support Thai food producers, especially small and medium-sized enterprises (SMEs), by providing access to innovative technology for producing safe, high-quality foods. At GNT, we have worked to adapt and localize this technology to meet the specific needs of SMEs. Through engineering redesign, local component sourcing, and modular system development, we have successfully reduced costs and simplified operation, making the system accessible and practical for smaller producers.
Our systems are now compact, energy-efficient, and can be integrated into existing production lines with minimal disruption. We also provide technical support, operator training, and process validation to ensure a smooth transition and long-term value.
You mentioned superior product quality when using this technology. Can you elaborate?
The superior product quality achieved through ohmic heating is primarily due to its unique heating mechanism. Unlike conventional thermal processes that rely on heat transfer from outside to inside, ohmic heating uses electrical current that flows directly through the food, generating heat uniformly and rapidly throughout the product. This results in reducing processing time, minimizing thermal damage and preserving nutritional, sensory, and structural attributes (Ghnimi et al., 2021; Gavahian et al., 2025). Its applicability across a broad spectrum of products, including high-viscosity liquid foods, fruit juices, and antioxidant-rich beverages, underscores its versatility and industrial scalability. The following sections present specific examples that demonstrate how OH preserves and even enhances quality parameters compared to conventional methods, substantiated by both lab-scale findings and full-scale continuous system data. For mixed berry juice containing pulp, the preservation of labile nutrients such as vitamin C, anthocyanins, ellagic acid, and flavonols is particularly critical. These compounds are highly sensitive to thermal degradation, especially in oxygenated and high-temperature conditions. Internal results from KU Ohmic Lab (2024) revealed that continuous OH processing of date juice at F₀ = 6 resulted in 63% retention of ascorbic acid (25.98 mg/100 mL), while conventional thermal treatment under identical microbial safety parameters retained only 10% (4.04 mg/100 mL). In addition, Ferreira-Santos et al. (2023) reported that total phenolic content increased by up to 48% and antioxidant capacity by over 50% in grape pomace extracts treated via OH compared to traditional methods.
For sugarcane juice, a product naturally rich in chlorogenic acid, caffeic acid, and flavonoids, the challenge lies in enzyme-induced browning, primarily caused by polyphenol oxidase (PPO). The KU Ohmic Lab (2024) reported that OH treatment enabled a 63% retention of total phenolics, in contrast to just 44% under conventional heating, attributing this to the faster PPO inactivation at lower cumulative thermal load. In aromatic coconut water, Zulekha et al. (2018) demonstrated that OH treatment at 74°C for 15 s resulted in 97% retention of tyrosol and total phenolics, whereas conventional pasteurization retained only 90% and 93%, respectively. Coconut water is highly vulnerable to loss of antioxidants, amino acids, and volatile flavor compounds under prolonged heating. Cabas and Icier (2021) showed that continuous OH processing of red beetroot resulted in superior phenolic retention and more vibrant color when compared to traditional thermal methods.
The benefits of OH are particularly evident in orange juice, a product with high levels of ascorbic acid, hesperidin, narirutin, and volatile terpenes such as limonene and myrcene. Leizerson and Shimoni (2005) reported that orange juice treated via continuous OH exhibited stable ascorbic acid levels and superior flavor stability over a 105-day refrigerated storage period, while conventionally treated juice began to deteriorate after only 79 days. The authors attributed this result to the lower cumulative thermal effect and uniform heating of OH, which preserved the native sensory profile of the juice. In a parallel study, Achir et al. (2016) evaluated carotenoid retention in orange and grapefruit juices and found that xanthophyll and carotene degradation was significantly lower in OH-treated samples compared to conventional heating.
In dulce de leche, a dairy-based product with high viscosity and solid content, OH has also proven to be superior to conventional heating in terms of structural and sensory quality. Silva et al. (2020) evaluated continuous OH treatment at 72–75 °C for 15 s and reported higher consumer acceptability scores than conventional methods across multiple attributes: color (8.15 ± 0.75), aroma (7.60 ± 1.19), taste (8.50 ± 0.76), and mouthfeel (8.45 ± 0.94). The authors noted that OH prevented local overheating and uncontrolled browning, leading to better retention of flavor and texture. This paper concluded that the homogeneity of heating in OH systems is particularly well-suited for dairy products where even slight inconsistencies in heat distribution can lead to significant quality losses.
In addition to the core applications described above, further validation of OH’s flexibility and scalability is evidenced by its successful application in a wide variety of other food systems. According to the review by Gavahian et al. (2025), OH technology has been applied effectively to liquid whole eggs, tomato puree, peeled whole tomatoes, watermelon juice, red beetroot juice, apple–sour cherry juice, olive paste, olive leaf extract, soy-based beverages, seaweed extracts such as Gracilaria vermiculophylla, and mixed vegetable pulps. These diverse matrices vary significantly in viscosity, pH, electrical conductivity, and nutrient composition, yet all responded positively to OH treatment in terms of improved product safety, nutrient retention, and process sustainability. The successful processing of such a wide range of products not only underscores the adaptability of OH but also confirms its capacity to maintain high quality under a range of industrial conditions.
What are the advantages of using this technology compared to conventional methods?
Ohmic heating offers several key advantages over conventional thermal processing methods such as retort or tubular heat exchangers:
- Faster Heating
Heat is generated directly within the food, significantly reducing the time needed to reach target temperatures. For example, sterilization with ohmic heating can be achieved within 1-2 min, compared to 10 min using tubular heat exchanger and 60 min using conventional retort (Vignali et al., 2022). - Uniform Heating
Ohmic heating ensures even heat distribution throughout both the liquid and solid phases, minimizing the risk of under- or over-processing—especially important for particulate-containing products (Sarang et al., 2008). - Superior Product Quality
Rapid and uniform heating helps retain natural flavor, color, texture, and nutrients, delivering a fresher and more appealing product (Silva et al. 2020; Kumar et al., 2014). - Higher Energy Efficiency
With fewer heat losses and no need for steam boilers, ohmic systems can achieve up to 97% energy efficiency (Lee et al., 2015), compared to ~45% in conventional heating (Atuonwu et al, 2018). - Environmentally Friendly
The system uses electrical energy, which can be sourced from renewable energy, reducing dependence on fossil fuels and lowering carbon emissions (Ghnimi et al., 2021; Gavahian et al., 2025). - Reduced Fouling and Cleaning Time
Ohmic heating results in less fouling on heating surfaces, decreasing downtime and cleaning costs compared to UHT systems (Zell et al., 2009; Bansal and Chen et al., 2005).
These advantages make ohmic heating an excellent solution for companies seeking to enhance product quality, efficiency, and sustainability.
So far, do you have any clients that already use this technology in their production?
Yes, we are currently working with food companies in Thailand that have adopted our ohmic heating technology to produce Thai fruit syrups, juices, and other liquid-based products.
How is this technology compatible with the sustainable objectives of these companies ?
The OH technology demonstrates strong compatibility with sustainable objectives of companies, primarily by virtue of its designation as a Green Novel Technology (GNT). The system boasts a remarkably high energy efficiency, with direct energy-to-heat conversion reaching between 90 and 97% (Lee et al., 2015), which significantly reduces overall energy consumption compared to conventional methods, a critical factor in lowering operational costs and, crucially, minimizing environmental impact.
OH also plays a significant role in reducing greenhouse gas emissions. For instance, replacing traditional appertization with OH in tomato processing has been shown to cut greenhouse gas emissions by up to 65%, a substantial decrease in global warming potential (Ghnimi et al., 2021). This direct contribution makes OH a strong ally in achieving key United Nations Sustainable Development Goals (SDGs), particularly SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action). Beyond its energy and emissions benefits, OH further supports SDG 12 (Responsible Consumption and Production) by enabling the valorization of food waste and aligns with SDG 2 (Zero Hunger) and SDG 3 (Good Health and Well-being) through enhanced shelf life and superior nutrient preservation in food products (Gavahian et al., 2025).
Moreover, the operational efficiencies inherent in OH systems contribute directly to sustainable practices. OH exhibits up to 90% reduction in fouling compared to conventional methods (Bansal and Chen et al., 2005). This translates into longer continuous operation, improved hygiene, and less frequent cleaning intervals. Consequently, it conserves water and cleaning chemicals and reduces microbial risks, reinforcing its alignment with responsible production methods. These combined attributes firmly establish OH as a technologically advanced and inherently sustainable solution for modern food and beverage manufacturing.
What can your company (GNT) offer in terms of services to manufacturers that would like to try this technology?
We offer a complete range of services designed to help food and beverage manufacturers explore, test, and successfully adopt ohmic heating technology—regardless of their production scale or technical background. From small-scale trials to full-scale system integration, we provide flexible and practical solutions tailored to real production needs.
For companies just beginning to explore the technology, we offer lab-scale testing services. This setup allows manufacturers to trial their actual products—whether it’s fruit juices, herbal drinks, sauces, vegetable purees, protein-rich formulations, soups, or plant-based beverages—in small batches. This early-stage testing helps assess how ohmic heating interacts with each unique formulation, including those with particulates, high viscosity, or heat-sensitive nutrients. It’s a low-risk, data-driven way to evaluate product quality, heating efficiency, and shelf-life potential before scaling up.
For businesses that want to enter the market quickly or test consumer response without investing in equipment, we provide OEM (Original Equipment Manufacturing) services. Through this model, clients can produce their ohmic-heated products at our facility, under their own brand. It’s an ideal solution for startups, pilot projects, and limited-edition runs. Our OEM partners benefit from hands-on access to the technology while maintaining full control over their formulation and branding.
For companies ready to bring the technology in-house, we offer custom-designed ohmic heating systems engineered to match specific product characteristics and production volumes. Whether you’re processing a smooth beverage, a thick protein-rich shake, a sauce with visible particulates, or a creamy soup, we tailor each system to ensure uniform heating, energy efficiency, and consistent quality. Our equipment can be integrated seamlessly into existing lines, and our modular design allows for future scaling.
Beyond equipment, our support extends to on-site training, technical consultation, and post-installation optimization. We train production teams on system operation, safety, process control, and troubleshooting. Our engineers and food scientists also provide ongoing support to fine-tune product parameters, improve process efficiency, and assist with regulatory or shelf-life testing as needed. With these four key service pillars—lab-scale testing, OEM production, customized system design, and full technical support—we aim to make ohmic heating technology practical and accessible for a wide range of applications. Whether you’re working with juices, soups, sauces, purees, or high-protein beverages, we are here to help turn innovative product ideas into reliable, high-quality, and scalable production reality.
