The enhancement of the health potential of prickly pear fruits with the use of high hydrostatic pressure

Abstract

Prickly pear (Opuntia ficus-indica L. Mill.) fruits are low-cost, sustainable sources of bioactive compounds which could contribute to the reduction of risk factors related to obesity and metabolic syndrome. However, for prickly pears to exert mentioned health benefits, bioactive compounds must be first released from the food matrix, transformed in the gastrointestinal tract and absorbed by our bodies. High hydrostatic pressure (HHP) is an innovative food processing technology which affects the microstructure of the foods and modifies/ruptures intracellular compartments where bioactive compounds are located. Thus, contributing to their immediate release as well as to their release in the gastrointestinal tract in early, intermediate or late stages of digestion. The aim of this dissertation was to enhance the health potential of prickly pear fruits with the use of HHP by increasing the bioaccessibility of their bioactive compounds. To achieve this goal, the following topics were thoroughly assessed: (i) the characterization and quantification of bioactive compounds (betalains, phenolic compounds, carotenoids and ascorbic acid) in different Mexican and Spanish prickly pear fruits; (ii) the antioxidant, anti-inflammatory, anti-hyperglycemic and delipidating activity of their extracts and of their main isolated bioactive compounds; (iii) the effect of HHP on target bioactive compounds in prickly pear fruits, their bioactivity and microstructure; and (iv) the in vitro digestive stability and bioaccessibility of bioactive compounds in control and HHP-treated prickly pear fruits. On one hand, pulps were studied due to their importance as the edible fraction of the fruit. Meanwhile, peels were evaluated because they may be used as by-products to obtain healthy ingredients. The major finding of this dissertation was that HHP could, in fact, enhance the bioaccessibility of bioactive compounds in prickly pear fruits, thus contributing to their health potential. The studies included in this dissertation have been carried out hoping to contribute to the use of innovative technologies for the development of healthy foods so that we can live longer and healthier lives.