Tesis
Efecto de pretratamientos en la extracción de antocianinas de la Mora Castilla (R. glaucus) y Silvestre (R. adenotrichos), para su uso como indicador visual de pH.
Autor
Cuesta Riaño, Cristhian Santiago
Castro Guasca, María Paula
Institución
Resumen
The blackberry is one of the most representative fruits in terms of geographical coverage
seeded in Colombia and contain phenolic compounds including anthocyanins. The main
objective of this research was to evaluate and analyze the use of pretreatments (microwave,
ultrasound and lyophilization) to improve the traditional extraction of anthocyanins in two
varieties of Castilla blackberry (R. glaucus) and wild blackberry (R. adenotrichos), for later
application as visual pH indicator. A factorial experimental design was developed: two levels
and four factors (24). The anthocyanins content was quantified by differential pH method.
Then, the antioxidant activity of DPPH and FRAP assays results was determined. In
addition, the extract color was measured at different pH values to be used as a pH visual
indicator.
It was possible to conceptualize that the blackberry variety and lyophilization and ultrasound
pretreatments showed significant differences while the microwave treatment did not have a
significant effect on extraction. The best extracts were obtained by applying the combination
of lyophilization and ultrasound pretreatments. Castilla blackberry achieved an anthocyanin
content of 187.96 ± 11.28 mg of cyanidin-3-glucoside / 100 g of fruit and an antioxidant
power of 3, 89 ± 0.14 μmol Trolox / g sample according to the DPPH test and 3.40 ± 0.04
~ 3 ~
μmol Trolox / g sample according to the FRAP test. Wild blackberry reached an anthocyanin
content of 394.53 ± 24.11 mg of cyanidin-3-glucoside / 100 g of fruit and an antioxidant
power of 4.33 ± 0.04 μmol Trolox / g sample according to the test of DPPH and 3.51 ± 0.01
μmol Trolox / g sample according to the FRAP test. Finally, the analysis of results showed
that extracts can be used as visual pH indicators, highlighting better results when using wild
blackberries.