Tomato pomace is a significant byproduct derived from processing tomatoes into various products such as paste, juice, and sauces. As a considerable portion of the original fruit, it is a readily available resource. This co-product is gaining attention for its potential in diverse applications, moving beyond traditional disposal methods towards more valuable uses.
What is Tomato Pomace?
Tomato pomace is a solid residue remaining after industrial tomato processing, primarily composed of skins, seeds, and a small amount of pulp. This mixture constitutes a notable percentage of the initial processed tomatoes, generally between 10% and 40%. Its formation involves crushing whole tomatoes, heating them to break down tissues, and then pressing them to separate liquid components from the solid residues.
Once considered waste, this byproduct is now recognized as a valuable co-product due to its rich composition. Its high moisture content, often exceeding 75%, requires proper handling to prevent rapid spoilage. Drying or ensiling are common preservation methods used to extend its shelf life and facilitate its utilization in various industries.
Nutritional Value and Components
Tomato pomace contains a rich array of beneficial compounds. It has high levels of dietary fiber, encompassing both soluble and insoluble types, which generally range from 33% to 57% on a dry matter basis. Proteins are also present in notable amounts, typically between 17% and 22% of its dry matter, with defatted tomato seeds showing higher protein content.
It is also a source of antioxidant bioactive compounds. These include carotenoids, such as lycopene and beta-carotene, which are responsible for the tomato’s characteristic red color and possess strong antioxidant properties. Tocopherols, a form of Vitamin E, and various polyphenols are also present, further contributing to its antioxidant capacity. The fat content can range from 10% to 15% on a dry matter basis, sometimes exceeding 20% if the proportion of seeds is high, with linoleic, linolenic, and oleic acids being dominant fatty acids.
Applications Across Industries
Tomato pomace finds widespread application, particularly in animal nutrition. It is a common ingredient in livestock feed for cattle, poultry, and swine, valued for its fiber and protein content that supports digestive health and overall animal well-being. For instance, including dried tomato pomace in the diet of rabbits can provide digestible energy, protein, and fiber, which helps control digestive diseases. In ruminants, it can improve feed intake and growth performance, and studies suggest it can reduce methane production and enhance the fatty acid profile of meat.
Beyond animal feed, tomato pomace is gaining recognition in human food and supplement industries. Its fiber-rich composition makes it suitable for enriching baked goods or snacks. It also serves as a source for extracting valuable antioxidants like lycopene for use in dietary supplements. This extraction capitalizes on the high concentration of lycopene, which can constitute 80% to 90% of the total carotenoids in tomato pomace.
Tomato pomace also demonstrates potential in broader industrial and environmental contexts. It can be explored as a feedstock for biofuel production. Its organic matter also makes it a suitable component in composting processes, aiding in nutrient recycling. Research suggests its possible use in developing bioplastics or other valuable industrial compounds, showcasing its versatility as a sustainable resource.