Characterization of tomato processing by-product for use as a potential functional food ingredient: nutritional composition, antioxidant activity and bioactive compounds

Abstract

Tomato pomace, a by-product generated during tomato processing, was collected at a large tomato processing industry. The by-product was mainly constituted of tomato skin (61.5%), and presented high moisture content (66.58 g.100g wet basis). Among the nutrients, the highest content was of dietary fibre, followed by proteins and fat (50.74, 20.91, 14.14 g.100g d.w., respectively). The pomace has high in vitro antioxidation capacity, especially when measured with the TEAC assay (224.81 μmol Trolox equivalent 100g d.w.). This is due especially to the high amount of lycopene remaining in the by-product after processing (446.9 μg.g d.w). The waste was fractioned into skin and seed fractions by sedimentation, resulting in the increase of lycopene yield by 55%, when using skin fraction as the source material in place of the whole pomace. This by-product shows great potential for being used as a source of the ingredients of high nutritional value, especially dietary fibre and lycopene.

Recent Advances in Recovery of Lycopene from Tomato Waste: A Potent Antioxidant with Endless Benefits

“…Tomato processing generates high amounts of by-products that represent an environmental inconvenience for producers but at the same time a source of bioactive compounds [ 5 ]. According to the common processing, industries produce as tomato by-products (TBPs) peel, seeds or pomace which consists mainly of peel, seeds and a small amount of pulp and represents up to 5% of the whole tomato [ 6 ]. TBP is a source of valuable compounds: minerals, vitamins dietary fibers, proteins, polyphenols and carotenoids [ 7 ].…”

Lycopene in tomatoes and tomato products

“…During the processing of tomatoes, the main residue generated is the tomato pomace [7]. The by-products of tomatoes, especially tomato pomace, are an important source of functional food ingredients such as dietary fiber, β-carotene, lycopene, phenolic acids (ellagic and chlorogenic acids), and flavonoids (rutin and myricetin) [8][9][10][11][12].…”

Terpenoids and Polyphenols as Natural Antioxidant Agents in Food Preservation

“…This industry generates large quantities of tomato pomace, which consists of a mixture of skins and seeds with a small fraction of pulp residues rich in carotenes (lycopene, ß-carotene or lutein) ( Figure 2 ), phenolic compounds (flavonoids) and vitamins (ascorbic acid and tocopherols) ( Figure 1 ). Among all of those, lycopene constitutes 80–90% of the total pigments and is of special interest to the meat industry, not only for its known in vitro antioxidant activity, but also its prevention of discoloration [ 95 , 96 , 97 ]. In this context, two concentrations of tomato powder (1% and 2%) were added to emulsified pork sausages and the antioxidant potential was similar to that obtained with 0.01% BHT during 28 days of storage at 10 °C [ 98 ].…”