Blood oranges are rich in antioxidants and other health-promoting phytochemicals and could provide significant benefits to both consumers and growers when stored at cool temperatures, according to a new University of Florida study. However, more research is needed to assess their viability as a commercial crop in Florida, despite their potential for higher market prices and quality improvements through special storage conditions. Photo credit: Ali Sarkhosh, UF/IFAS
A University of Florida One study suggests that storing blood oranges at cool temperatures increases their health benefits and market value, but more research is needed to determine their commercial viability in Florida.
A new study from the University of Florida shows that storing oranges at cool temperatures can improve their antioxidant properties and other health benefits, offering potential advantages for both consumers and citrus growers.
However, it is still too early to judge whether these so-called “blood oranges” are a useful addition to Florida’s citrus industry, says Ali Sarkhosh, associate professor of horticultural sciences at UF/IFAS.
“Although blood oranges typically command higher prices than other common varieties such as navel or Valencia oranges, it is unclear whether farmers could significantly increase their income per acre by including them in their crop yields and then storing them for internal color development,” said Habibi, the study’s lead author. “The improved fruit quality provided by the storage method represents a promising opportunity for the Florida citrus industry. However, more studies are needed before anything can be recommended to farmers.”
The fruit is rich in anthocyanins, which are associated with various health-promoting properties, including anti-inflammatory and antioxidant properties. They also contain other beneficial phytochemicals such as vitamin C, flavonoids and fiber.
UF/IFAS postdoctoral fellow Fariborz Habibi studies blood oranges in the lab. Photo credit: Ali Sarkhosh, UF/IFAS
Storage conditions and fruit quality
“Fruit can develop internal color under similar conditions at home. However, the fruit in the supermarket should have good internal color and be ready to eat,” Sarkhosh said.
For this study, scientists harvested fruit from a research plot at the UF/IFAS North Florida Research and Education Center in Quincy.
Scientists found that storing blood oranges at 40 to 53 degrees increased anthocyanin, phenol and antioxidant content. When they lowered the temperature to 43 to 46 degrees, they also preserved the fruit’s firmness, weight loss and sugar content.
“Properties such as firmness are critical to maintaining the overall quality, texture and flavor of blood oranges during storage,” said Habibi.
Blood oranges get their name from their deep red flesh. Their peel contains a type of antioxidant pigment. The fruit is commonly grown in countries such as Italy and Spain, whose Mediterranean climates – cold but above 0 °C – favor their growth. In the United States, blood oranges grow mainly in California, but are not yet grown commercially in Florida.
Anthocyanins are produced when the fruit is exposed to cold temperatures between 8 and 15 degrees for at least 20 days. Such conditions are rare in Florida’s subtropical climate.
Reference: “Postharvest storage temperature strategies affect anthocyanin content, total phenolic content, antioxidant activity, juice chemical properties, and physical properties of blood orange fruit” by Fariborz Habibi, Muhammad A. Shahid, Robert Logan Spicer, Cătălin Voiniciuc, Jeongim Kim, Frederick G. Gmitter Jr., Jeffrey K. Brecht, and Ali Sarkhosh, May 8, 2024, Advances in food chemistry.
DOI: 10.1016/j.focha.2024.100722
