Carotenoides e ésteres de carotenoides em diferentes cultivares de citros: amadurecimento e bioacessibilidade

Author(s)

Fabiane Cristina Petry

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos
• Defense date: 2017-06-27

Examining board members

Adriana Zerlotti Mercadante; Juliana Azevedo Lima Pallone; Lilian Regina Barros Mariutti; Rodrigo Rocha Latado; Solange Guidolin Canniatti Brazaca

• Advisor: Adriana Zerlotti Mercadante

Abstract

Carotenoids are responsible for the color from most citrus cultivars. Besides color properties, they also show important biological actions in humans. Carotenoids are present in both free form and esterified with fatty acids in fruits; therefore, determination of the native composition of carotenoids in meals is necessary, since this is the actual form they are ingested. Along with carotenoid composition of foods, knowledge about the amount of carotenoid that will be absorbed and available to play their bioactive function is also important. In this study, carotenoids from different citrus cultivars were investigated for composition, changes during ripening and bioaccessibility. In some studies, mango was employed for comparison with citrus due to its simple and well-established carotenoid composition. Herein, a new method for carotenoid extraction and analysis in freeze-dried citrus pulp was developed. Carotenoids were extracted by magnetic stirring with ethyl acetate and methanol, and sodium carbonate was added previously to extraction. Liquid-liquid partition was carried out in centrifuge. The developed method is accurate, precise, faster than the maceration with mortar and pestle traditionally employed for carotenoid extraction, and was successfully applied to determine carotenoid composition of orange cv. `Valencia¿ and mango. This developed method was also employed for carotenoid analysis in tangor cv. `Murcott¿, orange cv. `Pera¿ and new hybrids between these cultivars, in different ripening stages. The hybrids were developed by the Agronomic Institute of Campinas to overcome economic losses caused by phytosanitary disorders of citrus, by increasing the number of citrus cultivars and combining resistance of mandarins and orange against different diseases. All hybrids showed higher provitamin A content and more appropriate colors for juice industry as well as for in natura consumption compared with the parental orange cv. `Pera¿. Moreover, as a result of the intense carotenoid biosynthesis during ripening, an increase in the carotenoid contents in pulp was observed in all citrus samples, as well as characteristic alterations in peel and pulp colors. Native carotenoid composition of carotenoids in orange cvs. `Valencia¿ and `Pera¿, tangor cv. `Murcott¿ and mango was also determined, and most compounds were reported for the first time in these samples. In orange cultivars, 9 free carotenoids, 38 monoesters and 60 diesters were identified, and the major compounds were violaxanthin, luteoxanthin and antheraxanthin derivatives. In tangor, 8 free carotenoids, 34 monoesters and 33 diesters were identified, and ?-cryptoxanthin and violaxanthin esters were the major compounds. In citrus samples, carotenoids were esterified mainly with lauric, myristic, palmitic, palmitoleic and oleic acids. In mango, 5 free carotenoids, 2 monoesters and 19 diesters were identified. Finally, the composition and bioaccessibility of carotenoids (carotenes, free and esterified xanthophylls) were determined for the first time in mandarin cultivars harvested in Brazil. Differences in the carotenoid content and the major compound were observed among cultivars. Bioaccessibility of carotenoids ranged from 11% to 41% and was influenced by mandarin cultivar and carotenoid polarity. Bioaccessibility of (all-E)-ß-cryptoxanthin was higher than that of its esters and that of (all-E)-ß-carotene in all the cultivars (AU)

• FAPESP's process: 13/09804-5 - Carotenoids and carotenoid esters in different Citrus cultivars: composition, bioacessibility and changes during ripeness
• Grantee: Fabiane Cristina Petry
• Support Opportunities: Scholarships in Brazil - Doctorate