Yerba-mate (Ilex paraguariensis St. Hil.) has long been cherished for its energizing leaves, which are widely consumed in South America as a traditional tea. However, recent studies have unveiled that the fruits of the yerba-mate plant, which were previously discarded as waste, contain numerous health benefits and commercial possibilities.
The Science Behind Ripening and Nutritional Value
A significant aspect of this study focuses on the ripening process and how it affects the nutritional value of yerba-mate fruits. Over a 90-day period, scientists closely monitored the physical changes in the fruit, noting increases in size and weight.
The fruit’s diameter expanded from 5.34 mm to 6.31 mm, while its mass nearly doubled from 0.0877g to 0.1951g. Despite these changes, the density remained consistently above 1 g/cm³ throughout maturation.
Additionally, researchers analyzed the color transformation using advanced CIELAB measurements. The lightness of the fruit (L) decreased significantly from 48.74 to 25.72, while the green-to-red shift (a) increased from -10.23 to 4.19.
Meanwhile, blue tones appeared as the b values dropped from 23.10 to 4.47. These visual changes indicate a rise in anthocyanin levels, which are the same potent antioxidants found in berries like blueberries and blackberries.
The Best Drying Methods for Maximum Nutrient Retention
Processing yerba-mate fruits efficiently while maintaining their health benefits is crucial. This study compared different drying techniques to identify the best method for retaining the fruit’s beneficial compounds.
Three temperatures were tested—60°C, 80°C, and 110°C—each with varying drying times and energy requirements. At 60°C, drying took 570 minutes and consumed 54.322 kWh of energy, making it the best option for preserving anthocyanins.
The 80°C method offered a more balanced approach, requiring 300 minutes and using 44.713 kWh.
Meanwhile, drying at 110°C was the fastest, completing in 225 minutes with an energy consumption of 39.979 kWh, making it ideal for retaining saponins.
Notably, unripe fruits dried 42% faster than ripe ones, and the highest moisture diffusivity was recorded at 110°C. Moreover, ripe fruits demanded more energy to dry, with values reaching 24.96 kJ/mol compared to 21.21 kJ/mol for unripe fruits.
The Bioactive Compounds That Make Yerba-Mate Special
Yerba-mate fruits contain a variety of beneficial compounds, including saponins, anthocyanins, and antioxidants. Saponins were found in higher concentrations in unripe fruits and remained stable even at 110°C, suggesting their potential for medicinal extraction, particularly in cholesterol management.
Anthocyanins, which are more abundant in ripe fruits, were highly sensitive to heat and were best preserved at 60°C. These compounds also show promise as natural food colorants.
Unripe fruits exhibited superior antioxidant properties, performing well in DPPH radical scavenging, ABTS electron donation, and FRAP iron reduction tests. These antioxidant activities suggest potential benefits in preventing oxidative stress-related diseases.
The Nutritional Superiority of Yerba-Mate Seed Oil
Another valuable component of yerba-mate fruits is the oil extracted from their seeds. The study revealed an exceptional fatty acid profile in yerba-mate seed oil, making it a highly nutritious option.
The oil consists of 43.11% linoleic acid (omega-6), 37.68% oleic acid (omega-9), and only 19.21% saturated fats.
Compared to other widely used oils like soybean or sunflower oil, yerba-mate seed oil boasts a higher unsaturated fat content.This makes it an excellent candidate for heart-healthy food products, cosmetics, and other wellness applications.
Given the increasing demand for sustainable and health-focused oils, yerba-mate seed oil has the potential to replace less eco-friendly alternatives.
The Commercial Promise of Yerba-Mate Fruits
The commercial potential of yerba-mate fruits extends across various industries, particularly in health, food, and agriculture. In the health and wellness sector, saponin extracts could be developed into cholesterol-lowering supplements, while the antioxidant-rich composition of the fruit makes it suitable for dietary supplements.
Additionally, yerba-mate fruit-based energy boosters may provide an alternative to caffeine-heavy products, offering sustained energy without unwanted jitters. In the food industry, the natural pigments from anthocyanins can serve as vibrant and healthy food colorants.
Furthermore, functional food ingredients derived from the fruit can enhance nutritional value in everyday diets, while the specialty oil from yerba-mate seeds presents an exciting option for gourmet food applications. The agricultural sector can also benefit from these findings.
Saponin-rich extracts could be utilized in biodegradable pesticides, reducing reliance on synthetic chemicals. Additionally, plant growth enhancers and sustainable livestock feed additives derived from yerba-mate fruits could revolutionize farming practices.
Best Practices for Processing and Utilization
To make the most of these newfound benefits, farmers and processors must implement optimal harvesting and processing strategies. For those aiming to extract saponins, harvesting unripe fruits is the best approach, whereas fully ripened fruits should be prioritized for anthocyanin extraction.
When it comes to processing, drying at 60°C is ideal for applications requiring color retention, while 110°C drying is better suited for saponin-rich products. For seed oil production, cold pressing should be employed to maintain the oil’s high-quality nutritional profile.
Additionally, quality control measures, such as monitoring color changes as indicators of ripeness and tracking drying rates for energy efficiency, are essential for ensuring consistent product standards.
Testing the antioxidant activity of final products can further guarantee their effectiveness in health and wellness applications.
Future Research and Market Expansion
This research lays the foundation for future studies exploring additional processing methods, clinical validation, and market development. Alternative drying techniques, such as freeze drying, infrared drying, and enzymatic extraction, may further improve the preservation of bioactive compounds.
Additionally, clinical studies examining the effects of yerba-mate fruit extracts on human health, particularly in cholesterol reduction and antioxidant absorption, could provide scientific validation for these benefits.
Market development is another crucial aspect, as consumer acceptance, supply chain optimization, and economic feasibility studies will play a significant role in determining the commercial success of yerba-mate fruit-based products.
Conclusion
This comprehensive study highlights that yerba-mate fruits, once overlooked and discarded as waste, hold immense potential for various industries. By applying these findings, producers can transform what was once considered an agricultural byproduct into a valuable resource.
This not only opens new revenue streams but also promotes sustainable production practices and contributes to South America’s growing bioeconomy. With a 20.24% oil content in its seeds and a diverse phytochemical profile, yerba-mate fruit is well-positioned to become a sought-after natural ingredient in the global market.
As the demand for functional and natural food products continues to rise, these previously discarded fruits may soon become one of South America’s most valuable agricultural assets.
 Gandin, Y.E.M., Quast, L.B., Pinto, V.Z. et al. Drying and Bioactive Compounds Extraction of Ripe and Unripe Yerba-Mate Fruits. Plant Foods Hum Nutr80, 100 (2025). https://doi.org/10.1007/s11130-025-01342-7References:
