Evaluation of Phytochemical Composition of Tomato Serum as a Promising Ingredient for the Production of Healthy Food Products

In traditional methods of producing concentrated tomato products, excess moisture is removed by evaporation at atmospheric pressure or under vacuum. An alternative technology for processing tomatoes has been developed that involves removing tomato serum (TS) by separating tomato pulp. However, TS has not found wide commercial use at present, probably due to insufficient study of its composition and biological effects on the human body. As a result, a very limited number of studies of the chemical composition of TS have been published to date. The objective of this research is to analyze the phytochemical composition of TS with varying colors to determine its suitability for innovative food technologies. The analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC). Serum of the red-fruited, dark-colored, yellow-fruited tomatoes had an active acidity of 3.90-4.37 pH, contained 4.8-6.1% dry matter, of which 811.9-847.8 mg/dm3 were amino acids (the share of essential amino acids is 32.5-34.1%), mono- and disaccharides (3.48-6.50 % FW), organic acids (13.01-16.55 % DW) with a predominance of citric and tartaric acids, vitamins B1+B2 (<1.0 mg/dm3), B6 (up to 1.2 mg/dm3), PP (2.99-6.14 mg/dm3), C (20.32-22.51 mg/dm3). The sum of phenolic compounds is 212-254 mg/dm3, flavonols and flavanones were identified in TS. The antioxidant activity of TS was 139.11-168.58 mg/dm3 (reference quercetin). The ratio of the amount of Na to the amount of K in all analyzed samples was in the range of 0.01-0.02, the ratio of Ca:Mg and Ca:P was 1:1.6-1:1.8 and 1:1.3-1:4.3, respectively. The content of the anti-nutritional component – oxalic acid in TS is 24.46-42.38 mg/dm3. TS is safe in terms of toxic and potentially toxic elements. TS, with its wealth of phytochemicals, represents a promising source of raw materials for food manufacturers. The phytochemical composition of tomato serum indicates its potential for the production of functional products, including for strengthening the health of the cardiovascular system.