Chemometrical Methods Applied to Chemical Data of Raw and Cook Spinach (Chenopodium vulvaria) and Purslane (Potulacae oleracea)

Hundreds of edible wild plants form a vegetal environment that provides a supply of nutritious and delightful food. It also contains a wealth of nutritious ingredients such as proteins, iron, calcium, and vitamins, as well as fibers, and mineral salts that our bodies require. Knowing these plants also aids in preserving the traditional users' cultural heritage. It is crucial to describe, characterize, and search the nutritional content of these plants. This is a very intriguing topic to explore and advance due to the variety of plants that have been harvested and their usage in various industries (nutritional, medical, cosmetic, pharmaceutical). The leaves and stems of some plants are used in cooking or eaten raw in salads. The limited research that has been done in Algeria has not demonstrated the potential contribution of these items to ration balance. The aim of this work was to gauge the chemical composition of two raw and cooked plants, leaves and petioles of wild spinach (Chenopodium vulvaria) and leaves of purslane (Portulaca oleracea), and to apply chemometric methods to obtain information that permit their characterization. Five samples of ten bunches of each plant were purchased from different retail traders in different markets of Constantine (Algeria) and prepared according to standard AFNOR. The samples were analyzed by determining moisture, total lipids, proteins, ash, minerals, dietary fibers, as well as, total carbohydrates and energy value by calculation. A multivariate data analysis method such as principal components analysis (PCA), was applied on a data matrix consisting of the analytical parameters of raw and cooked spinach leaves and petioles; and of raw and cooked purslane leaves. The results obtained showed that the samples of cooked spinach were characterized by the total carbohydrate and nutritional fiber (ADF, NDF and lignin). As for raw spinach, it was associated with lipid, protein, dry matter, energy value, carbohydrate and ash. The PCA of minerals revealed that the leaves are separated from petioles and are richer in minerals. PCA also enabled demonstration of the distinction between raw and cooked purslane. The dry matter content of the leaves of spinach and purslane decreased after cooking. It would be interesting to continue the work by studying the composition of fatty acids, tocopherols and pigments. In addition, the study could be broadened to include other cooking methods, and harvested plants that grow in Algeria.