## 1 Introduction  
The European Environment Agency (EEA) has announced the need to move from a linear economy to a circular economy. In a linear economy, the central model for economic development is raw materials, which are taken, processed, consumed, and disposed of as waste. In a closed-loop economy, the recovery and valorisation of waste allow for materials to be reused and put back into the supply chain [1]. Using the economic model in question, some points of the European Green Deal (EGD) are being implemented. EGD is a package of initiatives to implement green transformation and then climate neutrality; it consists of 7 pillars. The EGD assumptions mainly focus on reducing greenhouse gas emissions and improving energy efficiency. The assumptions of the EGD mainly focus on reducing greenhouse gas emissions and improving energy efficiency. Such actions can result in reducing energy consumption, producing fewer harmful gases, while supporting local entrepreneurs by sourcing raw materials from nearby areas [2]. Each year, global fruit production exceeds 900 million tons. About 30% of the total amount of fruit produced is waste. Fibre and pomace comprise the largest portion of the fruit industry's wastes. Managing waste in the fruit industry is a major problem for producers and processed fruit [3]. A very significant portion of by-products from the fruit industry ends up in landfills. This production practice poses serious environmental hazards due to the high biological and chemical oxygen demand rate of such waste [4]. Despite its valuable properties, fruit pomace and other waste are still not properly managed. Many bioactive compounds can be extracted from the by-products [5]. Currently, the use of natural bioactive compounds in the food industry is hampered by laboratory-intensive and lengthy extraction and isolation methods. As technology advances, new, rapid and efficient technologies for extracting and separating natural compounds are emerging that can yield high-quality extracts with better yields, less time and less solvent consumption. However, the higher costs associated with these new technologies and the difficulty of adapting to industry standards remain a major challenge [6]. Fibre is defined as carbohydrates derived from plant cell walls, resistant starch and oligosaccharides resistant to gastric acidity, hydrolysis by mammalian enzymes and absorption in the upper gastrointestinal tract [7]. Several types of dietary fibre can be extracted from grain, fruit and vegetable processing waste. Dietary fibre is classified based on water solubility into soluble dietary fibre (SDF) and insoluble dietary fibre (IDF). Pectins (found in whole grains, legumes, etc. ), gums (found in legumes, etc.) and mucilages (found in aquatic plants, aloe vera, okra and glycoproteins from food additives) are examples of soluble dietary fibre, while cellulose (which provides glucose monomers found in fruits, roots and grains), hemicellulose (complex sugars found in cereal bran and grains) and lignin (aromatic alcohols found in vegetables) are examples of insoluble dietary fibre [8]. Dietary fibre extracted from plant wastes and by-products can be a rich source of polyphenols, flavonoids and carotenoids (e.g., hydrolysate polyphenols, hydrolysate tannins, proanthocyanidins). It can form a single matrix called antioxidant dietary fibre [9]. Compared to cereal fibre, fruit fibre has a much higher soluble fraction [10]. Fruit pomace is a by-product of pressing raw fruits for juice. They have a high water content, so there is a risk of developing undesirable microorganisms. Immediate drying of pomace is used in the fruit industry. As a by-product, dried pomace is a very inexpensive intermediate product that can be used in various industries [11]. Fruit pomace can be used to produce animal feed. The limitation is the quality of the resulting feed. Due to its low protein content, such feed is not a complete animal food [5].