Drying process for guava, lagundi leaves developed

A drying process and technique in producing high-quality guava and lagundi leaves for export have been developed.

The headway was achieved by researchers of the Leyte State University (LSU) in Baybay, Leyte, situated 120 kilometers south of Tacloban City.

The scientific study was undertaken by LSU researchers headed by Dr. Roberto D. Guarte in answer to the problem of entrepreneurs concerning the lack of standard drying process and techniques in producing high-quality leaves of the two medicinal plants.

Guava (Psidium guajava L.) and lagundi (Vitex negundo L.) are two of the most important medicinal plantsk in the country.

Guava leaves are boiled in water and this decoction is used to clean wounds and as a mouthwash against infection, swollen gums, and tooth decay.

Lagundi leaves are prepared into a decoction against asthma and cough.

Both fresh and dried leaves of the two plants can be used.

"It is important to dry and store their leaves so that the efficacy of the active ingredients in the leaves is maintained. It is also necessary to ensure that dried products have high quality so that they are acceptable even in foreign markets where demand for dried medicinal plants exists," stressed the Los Baños-based Philippine Council for Agriculture, Forestry, and Natural Resources Research and Development (PCARRD), which monitored and LSU study.

The research noted that temperature had a high significant effect on the drying behavior and rate of guava leaves.

Based on their study, the LSU researchers recommended a drying temperature of 50 degrees Celsius for guava where the volatile content of the leaves was observed to be high. Also, at this temperature the physical characteristics of the leaves are not destroyed and drying time is not long.

An air velocity of 0.35 meter per secoond (m/s) is also recommended because it has the least power consumption.

For lagundi leaves, a drying temperature of 50oC and air velocity of 0.50 m/s are recommended. These conditions ensure that the physical characteristics of the leaves are retained and that drying time is not too long. – Rudy A. Fernandez