Tomato by-products help develop antioxidant-rich foods, study says

By-products from tomato processing could be used to develop functional foods or extend shelf life as they contain bioactive phytochemicals that exert antioxidant properties, a new study at Harokopio University, Greece, claims.

The research team compared tomato processing by-products and unprocessed tomatoes by evaluating the presence of bioactive phytochemicals such as lycoepene, sterols, tocopherols, carotenes, terpenes, and total and simple polyphenols.

Phytochemicals are compounds that are found naturally in plants and are responsible for colour and organoleptic properties.

The study showed that on a dry weight (DW) basis, by-products of tomato processing had significantly lower levels of lycopene, but had high levels of ß-carotene, tocopherols, sterols and terpenes, and both unprocessed tomatoes and tomato waste had similar amount of total polyphenols.

Of the 18 polyphenols, hydroxycinnamic acids predominated in unprocessed tomatoes, while flavonoids predominated in tomato wastes, and the fatty acid profile in tomato by-products was also similar to that of unprocessed tomatoes.

The researchers concluded that the bioactive phytochemicals found in tomato by-products can withstand industrial processing methods, and most of these phytochemicals are known to demonstrate antioxidant properties.

Tomato by-products can be isolated from wastes and used as natural antioxidants for the formulation of functional foods and also in food systems to extend their shelf life, the researchers noted.

The study was published in the journal LWT – Food Science and Technology.

Over the past few years, tomato processing wastes have been subject to several studies in order to recover lycopene and ß-carotene through several extraction schemes.

Tomatoes are one of the most important vegetable crops across the world, with an annual production of 100 million tonnes in 144 countries.

 

Caption: Research concluded that the bioactive phytochemicals found in tomato by-products can withstand industrial processing methods and demonstrate antioxidant properties. Photo: Pluma.