Analysis of morphological, nutritional, chemical and functional properties of selected culinary herbs: curry leaves, pandan leaves, lemongrass, java galangal and allspice.

Abstract

Sri Lanka is well known for its diverse culinary tradition where culinary herbs play a pivotal role. There are numerous varieties of culinary herbs available in Sri Lanka, and the current study was conducted to examine the morphological, nutritional, chemical, and functional properties of widely used culinary herbs namely curry leaves (Wal-karapincha (Micromelum minutum), Meegon-karapincha (Clausena indica)), pandan leaves (Pandan-wangi (Pandanus amaryllifolius), Pandan-duri (Pandanus tectorius spp.)), lemongrass (White-sheath lemongrass (Cymbopogon citratus), Red-sheath lemongrass (Cymbopogon flexuosus)), Java-galangal (Kaempferia galanga), and Allspice (Pimenta dioica). The vegetative parts commonly used in cooking purposes was selected to examine the properties, and accordingly, the immature and mature leaves of curry leaves, mature pandan leaves, mature leaf and sheath of lemongrass, mature java-galangal leaf, fresh immature and mature leaves, and dry leaves of allspice were taken for the study. Fresh grinded samples were taken for the analysis of nutritional, chemical and functional properties. The methanol extract of each sample was taken for the analysis of functional properties. ANOVAOne- way and T-test used for statistical analysis highlighting significance differences (p<0.05). The leaf arrangement of Wal-karapincha leaves was found to be imparipinnate compound while Meegon-karapincha was paripinnate compound. Pandan-duri showed spines on the edge of the leaves while Pandan-wangi was spineless. Compared to white-sheath lemongrass the leaf blade of red-sheath lemongrass leaf was found to be sharper. Out of all the herbal species dry allspice leaves showed the highest fat content (10.03±0.01%), crude protein (7.88±0.01 %), and crude fiber (15.35±0.01 %) contents. The lowest pH value was observed in the fresh mature leaves and dry leaves of allspice (4.53±0.01 pH). Out of all the herbal species studied, the immature Walkarapincha showed the highest titratable acidity (0.83±0.05 %). The highest values of total soluble solid content (2.27±0.01) and total sugar contents (56.92±0.01 %) were observed in dried leaves of allspice. The immature leaves of allspice showed the highest total phenolic content (179.24±0.01mg GAE/g), total flavonoid content (119.17±0.026 mg QE/g) and DPPH scavenging activity (6671.79±0.08 mmol/g). According to the results each culinary herb showed significant differences in morphology, nutrition, chemical and functional properties. This research will stimulate further research and educate society about different culinary herb varieties.