Duy Tan University students make tea from corn guts

Discarded corn cobs are used by a group of students from Duy Tan University (Da Nang), combined with some additives to make tea and supplement nutrition.

The research was conducted by 5 students Nguyen Hoang Nhat Thang, Pham Thi Thanh Tam, Son Hoang Phu Qui, Doan Van Dinh Nguyen and Nguyen Tran Nhat Linh , Faculty of Environment and Natural Sciences, Duy Tan University, over a period of about 6 months.

Pham Thi Thanh Tam, group representative, said that in Vietnam, corn is the second most popular crop after rice. After processing, a large amount of corn guts are not reused and are discharged into the environment. Some places use corn guts as animal feed, mushroom growing medium. with low value.

Research shows that corn kernels contain many health-beneficial medicinal substances such as anthocyanin, beta-sitosterol, saponin, tannin and other polyphenol compounds . In particular, the anthocyanin content in corn kernels is rated higher than in the grain. This is an antioxidant that brings many health benefits such as improving cardiovascular function and preventing diabetes. Beta-sitosterol has the effect of controlling cholesterol levels, reducing cancer cell activity, and increasing immunity. These medicinal substances in corn kernels are used by the research team to make tea bags.

Tea from corn guts by Duy Tan University research team. (Photo: NVCC).

To extract tea, the corn cob is cleaned, then dried at 70 degrees Celsius for three hours. The dried product is then ground and sieved into a size range of 0.5 - 1 mm suitable for making tea bags. The raw material is then mixed with some additives such as cloves, stevia, cinnamon, rose with a ratio of 90% corn cob, the rest is other flavors. The mixed raw material is packaged into tea bags.

According to Nguyen Hoang Nhat Thang, the process of mixing the ingredients is considered the most important and time-consuming, with many different proportions to find the tea flavor that suits Vietnamese taste. Thang said, if too much cinnamon is added to create a strong flavor, it will overwhelm the other aromas. If too much stevia is added, the tea will be harsh and the drinker will not feel the sweet aftertaste of the corn.

Regarding color, the team had to mix ingredients to get the characteristic yellow color of tea. "The team did dozens of experiments to get the most suitable color and flavor ," Thang said. After many experiments , the tea has the characteristic yellow color of corn, the tea water has no residue. The tea has a slightly sweet taste, the harmonious aroma of the ingredients.

According to Le Thi Thanh Tam, in the tea production process, the corn cob has not been evaluated by the group for the possibility of metal residues during the growing process affecting the soil, water source. The group plans to look for raw material areas with certifications that meet the criteria of cleanliness and safety in the near future.

Cornmeal tea is aimed at people aged 20-50 because this group is often at high risk of obesity due to unhealthy diet and lifestyle. The sweet, easy-to-drink tea helps reduce bad cholesterol in the blood.

Team members introduce tea products made from corn guts at the Post-Harvest Processing Technology competition held in Ho Chi Minh City on November 23. (Photo: Ha An).

Ms. Pham Thi Nga, Lecturer of the Faculty of Environment and Natural Sciences, Duy Tan University, assessed that using corn cobs to make tea is not only good for health but also a source of discarded agricultural by-products, which is an idea with high environmental protection. By taking advantage of cheap raw materials, the group's tea bags have great potential for commercialization at affordable prices, suitable for most consumers. However, according to Ms. Nga, the group needs to conduct an assessment of the antioxidant capacity of the substances in the corn cobs. In addition, the group needs to research safe preservatives to increase the shelf life of tea bags, serving future business requirements.