Chemical characterization of yellow‐orange and purple varieties of Opuntia ficus‐indica fruits and thermal stability of their betalains

Abstract

Betalains are plant pigments with biological properties and can be used instead of synthetic colorants to confer color and functional properties to foods. The objective of this work was to carry out the chemical characterization of two varieties of prickly pear of Opuntia ficus‐indica, one of yellow‐orange coloration (Mandarina) and the other of purple coloration (Vigor), through measurements of chemical parameters and color in pulp, antioxidant activity, total phenolic compounds, and betalain content. Considering the thermolability of betalains and their potential applications in food, the thermal stability and activation energy of betacyanins from Vigor variety and betaxanthins from the Mandarina variety were also evaluated and compared with those from beetroot, the main source of betalains. Results for chemical characterization agreed with previous prickly pear reports of other regions, while the thermal degradation kinetics of betalains showed a first‐order degradation pattern with respect to time and temperature treatment. Betacyanins from Vigor prickly pear showed similar thermal stability to those from beetroot, which was reflected in similar values of activation energy, while betaxanthins from Mandarina prickly pear showed a higher stability, and therefore a higher activation energy, than those from beetroot. Based on the results, the prickly pear varieties used in this study can be considered as a good source of betalains with potential applications in food and, in addition, the methodology for the evaluation of thermostability can be used to compare the stability of betalains from different sources in a temperature range of 50–90°C. Practical Application The varieties of prickly pear used in this study can be considered a good source of red‐purple and yellow‐orange easily extractable pigments. In addition, we report a methodology that can be used for the evaluation of the thermal stability of these pigments and to compare this stability between different plant sources. Gaining knowledge on betalain thermal stability will make it possible to propose specific applications, for example, in processed foods requiring different pigment stabilities.

Opuntia ficus-indica (L.): An Overview of the Recent Application and Opportunities in Food

“…In the food industry, yellow-orange and purple prickly pear varieties are used as a source of red-violet and yellow-orange pigments, instead of synthetic colorants, for food coloring and functional properties. 51 In a recent study, 52 cladode mucilage, microparticles of yellow-orange prickly pear cactus pulp, and maltodextrin were utilized as an additional food coloring for yogurt. Furthermore, mucilage derived from the peel of OFI fruits is used as a byproduct with possible health advantages.…”

Ultrasound-assisted extraction and encapsulation of betalain from prickly pear: Process optimization, in-vitro digestive stability, and development of functional gummies

“…Beetroot is the primary source of betalains, but other sources include species from the genera Amaranthus, Hylocereus, and Celosia. Additionally, Opuntia species, commonly known as prickly pear, are rich in betalains as well as other nutrients such as flavonoids, ascorbate, phenolic acids, soluble fibers, niacin, and carotenoids [9] .…”

Identification of WRKY gene family members in amaranth based on a transcriptome database and functional analysis of AtrWRKY42-2 in betalain metabolism

“…Betalains exist in only 15 families in Caryophyllales and the fungus Amanita muscaria ( Clement and Mabry, 1996 ; Polturak et al., 2018 ). The stability of betalains from different sources varies in the temperature range of 50–90°C; accordingly, botanists use the thermal stability of betacyanins as a chemical classification index ( Martins et al., 2017 ; Carreón-Hidalgo et al., 2022 ). Betalains are classified as betacyanins and betaxanthins.…”