| Autor: |
Antonelli S; Departamento de Ciencia de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380000, Chile., Pozas S; Departamento de Ciencia de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380000, Chile., Saavedra-Torrico J; Escuela de Alimentos, DataChem Analytics, Pontificia Universidad Católica de Valparaíso, Valparaíso 2340025, Chile., Donders M; Panel de Cata Aceite de Oliva Virgen UTEM, Facultad de Ciencias Naturales, Matemática y del Medio Ambiente, Universidad Tecnológica Metropolitana, Santiago 7800002, Chile., Bustamante C; Panel de Cata Aceite de Oliva Virgen UTEM, Facultad de Ciencias Naturales, Matemática y del Medio Ambiente, Universidad Tecnológica Metropolitana, Santiago 7800002, Chile., Sepúlveda B; Centro Para el Desarrollo de la Química-CEPEDEQ, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380000, Chile., Tapia F; Instituto de Investigaciones Agropecuarias (INIA Intihuasi), La Serena 1700000, Chile., García-González DL; Instituto de la Grasa (CSIC), Edificio 46, Ctra. de Utrera, km. 1, 41013 Sevilla, Spain., Romero N; Departamento de Ciencia de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380000, Chile. |
| Abstrakt: |
The frequency of early frosts has increased in recent years, which are injurious to olive growing, causing losses in the yield and quality of virgin olive oil. In this research, it was studied how the management of agronomic factors mitigates frost damage in Arbequina olives, minimizing the loss of phenols and volatiles in virgin olive oil, at different fruit ripening stages. A Box-Behnken design and multivariate analysis were performed, with three levels of irrigation, potassium fertilization, and foliar copper application (15 treatments). Virgin olive oil was extracted from fresh and frozen olives. Light frost caused a significant decrease in the total phenols and secoiridoid compounds in and the antioxidant capacity of the frost-affected oils, which were perceived as more pungent and had the slight defect of "frostbitten olives". According to the Box-Behnken design, an 86% reference evapotranspiration (ET 0 ) or higher with 100 potassium oxide units (UK 2 O) and a 100% ET 0 or higher with 250 UK 2 O would be required to minimize the effect of light frost on phenols and volatiles. Partial Least Squares Regression-Discriminant Analysis (PLS-DA) differentiated the virgin olive oils according to their ripening stage and fresh and frost conditions. Moreover, PLS-DA positively correlated a 75-100% ET 0 and 0 Uk 2 O with the dialdehydic form of the decarboxymethyl ligstroside aglycone ( p -HPEA-EDA), the dialdehydic form of the decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA), the dialdehydic form of the ligstroside aglycone ( p -HPEA-EDA-DLA), and with fruity, pungent, and bitter attributes. Precision agronomic management based on the needs of the crop itself would avoid unnecessary stress on olive trees and oil damage. |
