Tomato derived polysaccharides for biotechnological applications: chemical and biological approaches

Functional and Nutraceutical Compounds of Tomatoes as Affected by Agronomic Practices, Postharvest Management, and Processing Methods: A Mini Review

Tomatoes and their by-products are indisputable sources of substances with antioxidants properties. Several factors limit the production and influence the nutritional and antioxidant quality of tomato fruit. However, consumers can benefit from the effects of environmental factors, such as water and hydric stress, UV radiation, agronomic practices, among others, which lead to changes in the content of secondary metabolites in tomatoes. Molecules as phenolic compounds, carotenoids, and biogenic amines are often formed in response to environmental adversities. In this way, the consumption of tomato fruits or their by-products with higher levels of antioxidants may be important adjuvants in the prevention or reduction of diseases. In this mini-review, we will present how pre- and postharvest conditions may influence the content of some bioactive compounds in tomatoes. Furthermore, we will present how some heat processing methods may change the antioxidant content, as well as, the functional and nutritional properties of the final product.

Assessment of Tomato Peels Suitable for Producing Biomethane within the Context of Circular Economy: A GIS-Based Model Analysis

Biomass is seen as one of the most dominant future renewable energy sources. In detail, agro-industrial by-products represent a cheap, renewable, and abundant feedstock useful for several new products, including biochemical, biomaterials, and above all biogas, which are taking on an ever-increasing role in Italy. In this context, the tomato chain was analysed aiming at estimating the amount of processed tomato and the related waste production as a new suitable resource for producing biofuel as a new frontier within the context of a circular economy. Due the importance of the tomato industry, this research aims at filling gaps in the knowledge of the production and yield of the by-products that are useful as biomass for energy use in those territorial areas where the biomethane sector is still developing. This aim could be relevant for planning the sustainable development of the biomethane sector by reducing both soil consumption for dedicated energy crops and GHG emissions coming from the biomass logistic supply. The achieved results show the localization of territorial areas highly characterized by this kind of biomass. Therefore, it would be desirable that the future policies of development in the biomethane sector consider the availability and the distribution of these suitable biomasses within the territory.

Production of FucoPol by Enterobacter A47 using waste tomato paste by-product as sole carbon source

Out-of-specification tomato paste, a by-product from the tomato processing industry, was used as the sole substrate for cultivation of the bacterium Enterobacter A47 and production of FucoPol, a value-added fucose-rich extracellular polysaccharide. Among the different tested fed-batch strategies, pH-stat, DO-stat and continuous substrate feeding, the highest production (8.77gL^-1) and overall volumetric productivity (2.92gL^-1d^-1) were obtained with continuous substrate feeding at a constant flow rate of 11gh^-1. The polymer produced had the typical FucoPol composition (37mol% fucose, 27mol% galactose, 23mol% glucose and 12mol% glucuronic acid, with an acyl groups content of 13wt%). The average molecular weight was 4.4×10⁶Da and the polydispersity index was 1.2. This study demonstrated that out-of-specification tomato paste is a suitable low-cost substrate for the production of FucoPol, thus providing a route for the valorization of this by-product into a high-value microbial product.

Bread enriched in lycopene and other bioactive compounds by addition of dry tomato waste

The tomato processing industry generates high amounts of waste, mainly tomato skins and seeds, which create environmental problems. These residues are attractive sources of valuable bioactive components and pigments. A relatively simple recovery technology could consist of production of powders to be directly incorporated into foods. Tomato waste coming from a Romanian tomato processing unit were analyzed for the content of several bioactive compounds like ascorbic acid, β-carotene, lycopene, total phenolics, mineral and trace elements. In addition, its antioxidant capacity was assayed. Results revealed that tomato waste (skins and seeds) could be successfully utilized as functional ingredient for the formulation of antioxidant rich functional foods. Dry tomato processing waste were used to supplement wheat flour at 6 and 10 % levels (w/w flour basis) and the effects on the bread's physicochemical, baking and sensorial characteristics were studied. The following changes were observed: increase in moisture content, titratable acidity and bread crumb elasticity, reduction in specific volume and bread crumb porosity. The addition of dry tomato waste at 6 % resulted in bread with good sensory characteristics and overall acceptability but as the amount of dry tomato waste increased to 10 %, bread was less acceptable.