Measurement of total anthocyanins content in flowering tea using near infrared spectroscopy combined with ant colony optimization models

Flowering tea has become a popular beverage consumed across the world. Anthocyanins content is considered as an important quality index of flowering tea. The feasibility of using near infrared (NIR) spectra at the wavelength range of 10,000–4000 cm−1 for rapid and nondestructive determination of total anthocyanins content in flowering tea was investigated. Ant colony optimization interval partial least squares (ACO-iPLS) and Genetic algorithm interval partial least squares (GA-iPLS) were used to develop calibration models for total anthocyanins content. Two characteristic wavelength regions (4590–4783, 5770–5963 cm−1), which corresponding to the ultraviolet/visible absorption bands of anthocyanins, were selected by ACO-iPLS. The optimal ACO-iPLS model for total anthocyanins content (R = 0.9856, RMSECV = 0.1198 mg/g) had better performance than full-spectrum PLS, iPLS, and GA-iPLS models. It could be concluded that NIR spectroscopy has significant potential in the nondestructive determination of total anthocyanins content in flowering tea.