Non-destructive Quantification of Anthocyanin Secondary Metabolites in Butterfly Pea ( Clitoria ternatea L.) Milk Powder: A Methodical Exploration by Vis-NIR and SWNIR Approach

Abstract Butterfly pea flowers are rich in chemicals that are beneficial for health. Its vibrant bluish-purple hue is attributable to anthocyanins which make it a popular natural colorant in functional foods and beverages. Several prospective analytical methods have been used to measure anthocyanin; however, these approach methods are still debated due to their shortcomings, including time consumption, need trained person, expensive cost, and the generation of chemical waste. This research investigated the feasibility of using Vis-NIR and SWNIR spectroscopy in combination with PLSR as an alternative, non-destructive method to determine anthocyanin levels in butterfly pea milk powder. The powder samples were formulated by adding butterfly pea extract at concentrations of 0.2%, 0.3%, and 0.4%, and subsequently dried at controlled temperatures of 50 °C, 60 °C, and 70 °C. The effective wavebands are evaluated to measure the model of anthocyanin in butterfly-pea milk powder by using a variable important in projection (VIP) technique. The results are shown in Vis-NIR and SWNIR has an R 2 > 0.80. The optimum model through the wavebands analysis by VIP method is potential for predicting anthocyanin content in butterfly-pea milk powder.