Is home squeezing worth the hassle when shop-bought OJ provides over 90% of daily vitamin C?

A new comparison study of the vitamin C and flavonoid content of freshly squeezed and shop-bought 100% orange juices shows that both types have similar concentrations of vitamin C after one week.

Amid a range of interesting results from the study published in the International Journal of Food Sciences and Nutrition, [1] the researchers also found that industrial squeezing results in higher levels of phenolic compounds, such as flavonoids, than those found in juices squeezed at home.

Additionally, the bioactive compounds in orange juices are preserved during a typical shelf-life period of two days, with the main bioactive compounds in both shop-bought and home-squeezed juices present at “nutritionally significant levels.”

The vitamin C found in orange juice plays a role in everything from neutralising free radicals, to iron absorption, to collagen production, to cholesterol metabolism, and bone formation. It is essential that humans get adequate amounts of Vitamin C through the diet because the body cannot make it.

Orange juice also contains flavonoids. Research has linked the consumption of flavonoid-rich foods and drinks to a lower incidence of type 2 diabetes, cardiovascular disease, and high cholesterol.

The researchers developed an equation to calculate how much vitamin C degrades over time. This allowed them to predict how long it takes freshly squeezed orange juice to reach the same concentration of vitamin C as shop-bought juice. They calculated this time to be 176 hours or 7.3 days.

The study also showed that 200ml of shop-bought or freshly squeezed juice contains enough vitamin C to meet EU adequate intake levels – 80 mg/day (women) and 90 mg/day (men) (EFSA 2013). In the EU and UK, the Nutrient Reference Value (NRV) for vitamin C has been set at 80 mg (R1169/2011).

In some countries, the recommended daily serving of fruit juice is 150 ml. Even at this lower daily amount, a glass of shop-bought orange juice still provides more than 90% of the NRV.

Among the different orange juices analysed, from France, the UK, Germany, and Spain, all except one met the criteria for the label “high content in Vitamin C.” This label requires foods to have a minimum of 15% of the NRV (R1924/2006 and R1169/2011).

In their conclusion, the researchers highlighted three important points:

●      Orange juices maintain their levels of bioactive compounds during a typical shelf-life period

●      The main bioactive compounds are present at nutritionally significant levels in both home-squeezed and shop-bought orange juices

●      Home-squeezed and shop-bought orange juices have similar vitamin C concentrations after one week

Reference

Salar FJ et al. (2024). https://pubmed.ncbi.nlm.nih.gov/38230429/