MCR-ALS and NIRS applied on the evaluation of the Lepidium meyenii antioxidant activity

Abstract

The Peruvian Maca (Lepidium Meyenii Walp) is a food which is widely consumed around the Peruvian Andes and has been used in Brazil thanks to medicinal properties attributed by popular culture. Due to lack of information on this cultivar, it was proposed a study to evaluate the effect of adding Peruvian Maca in transgenic soybean oil. For this purpose, the spectra of soybean oil samples with and without addition of Maca after heating at different temperatures were measured at Visible and Near Infrared regions. The results were evaluated by chemometric methods of Principal Component Analysis (PCA) and Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS). The results suggest that Maca inhibits the appearance of oxidation products, which is evidenced when comparing the results obtained for the heated oil with and without addition of Maca.

N-Way NIR Data Treatment through PARAFAC in the Evaluation of Protective Effect of Antioxidants in Soybean Oil

“…The addition of the plant-based substances directly to the antioxidant-free soybean oil samples was made following the methodology described by Soares et al [50]. Each plant-based substance was crushed, and 5% (w/v) of this one was added, individually, in the antioxidant-free soybean oil.…”

“…The experiments were conducted in an open system, simulating conventional frying. All samples were heated, and aliquots were collected at nine different temperatures (25,30,50,70,90,110,130,150, and 170 • C). These aliquots were put to cool at room temperature and NIR spectra were acquired after samples reached stable 25 • C for 30 min.…”