The aim of this research was to evaluate the influence of an in vitro gastrointestinal digestion on the stability and bioaccessibility of vitamin C and phenolic compounds (total phenolic content and flavonoids) in pulps and juices of Navel and CaraCara oranges and Clemenules mandarin freshly harvested and postharvest stored at 12ºC. Navel pulps and juices showed higher vitamin C content (41-44 mg/100 g fw) than Clemenules pulp and juice (35-36 mg/100 fw). Vitamin C in Clemenules increased 24% after 5 weeks at 12 ºC. In general, vitamin C bioaccessibility in pulps of oranges (85-90 %) and mandarin (95%) was significantly higher compared with juices (67%-oranges; 43%-mandarin). Navel and CaraCara pulps (33-34 mg/100 g fw) showed higher total phenolic content than juices (21 mg/100 g fw). Clemenules pulp and juice (21 mg/100 g fw) had different behavior after 5 weeks at 12 ºC. Thus, vitamin C content increased by 16% in pulp and decreased by 10% in juice. In general, the bioaccessibility of total phenolic content was quite similar in pulps and juices of both oranges and mandarin (75-80%). The main flavonoids identified in oranges and mandarin using HPLC-Q-MS was hesperidin and narirutin. The higher hesperidin and narirutin content was found in pulps of CaraCara (43.42 and 12.20 mg/100 g fw, respectively) and Navel (31.44 and 12.46 mg/100 g fw, respectively), being significantly lower (24-32%) in juices. Hesperidin bioaccessibility was very similar in oranges pulps (~45%) and juices (~50%). Similar results were found for narirutin. It is remarkable that hesperidin bioaccessibility decreased significantly to 10% in the pulp and juice of Clemenules. Also, narirutin bioaccesibility was only 3% in the mandarin juices. In general, the bioaccessibility of flavonoids was higher in oranges than in mandarin but not significant differences were found between pulp and juice of each citrus variety.

Resumen del póster presentado al XI Simposio Nacional y VIII Ibérico Sobre Maduración y Postcosecha celebrados en Valencia del 21 al 23 de octubre de 2014.

Peer Reviewed