According to scientists in New Zealand, eating a raw tomato may not be the best way to access it s healthy antioxidants - they say a mere 4% of the antioxidant lycopene is released from raw tomatoes.
Tomatoes are an important source of antioxidant compounds, such as lycopene, phenolics and ascorbic acid.
Research from Lincoln University, Canterbury has found that even though high levels of lycopene are present in tomatoes, only a small amount is released when they are digested by humans.
The study by Lincoln University scientists along with researchers from the New Zealand Institute for Crop & Food Research used a model of the digestive tract to simulate the activity of the human stomach and small intestine in order to measure the amount of lycopene and other antioxidants released from tomatoes during typical digestive conditions.
The study found that although around 75% of the total antioxidants were released, this included only 4% of the lycopene found in the raw tomato.
Nutritional biochemist Carolyn Lister says tomatoes are the richest source of lycopene in the human diet, as well as containing other antioxidants essential for health, but the human digestive tract is unable to release the majority of lycopene from raw tomatoes, so only a small amount is made available for the body to use.
Lister says processing tomatoes has been shown to make lycopene more bioavailable, so as well as eating raw tomatoes for their nutritional value, we should eat tomato sauces to get the goodness of the lycopene.
The research is published in the International Journal of Food Sciences and Nutrition.