Food additives have an essential role in the current industry and consumption habits, as they not only make food products more appealing, but they increase their stability and inherent safety. Overall, food additives may be defined as compounds/extracts that are added to a food product in order to accomplish a specific technological goal but are not ingested as a food product themselves. The additive must not pose a safety concern for the consumers health (when ingested) while fulfilling a specific technological need that cannot be satisfied through other reasonable means.

Microbiological processes can adversely affect the quality of food, leading to its spoilage. For this to occur, conditions that favor the growth and development of spoilage microorganisms must be met, such as bioavailable nutrients, favorable water activity, adequate pH value, presence/absence of oxygen, and redox potential. The term “food spoilage” is only applied if the changes in the foodstuffs due to the microorganisms’ potentially harmful metabolic products become recognizable, thus making the product unsafe for consumption and augmenting the risk of foodborne illness. However, not all microbiological change in food is considered harmful (for example, fermentation of grape juice in order to produce wine). Agro-food by-products, particularly fruit peels and seeds, have been regarded as a potential source of preservatives with several reports reporting on the potential antimicrobial activity of different fruit and vegetable by-product extracts, which could potentially be translated into an industrial application if the appropriate regulatory body gives a positive opinion.

Oxidation is a not a process exclusive to the human body. It occurs in every living organism and biological system, such as food products. Food oxidation may result in altered flavor, color, nutritional value, and texture, as well as create toxic compounds .As such, antioxidant compounds are one of the most important conservation technologies used by the food industry with their main function being the prevention of oxidative induced degradation of foods, therefore allowing for extended shelf times. These additives help stabilize lipids as well as other compounds and can neutralize free radicals, avoiding a cascade of oxidative reactions.Since plants are one of the main sources of antioxidants compounds, agricultural by-products are among the most relevant potential sources of natural antioxidants that could be exploited for product quality preservation. Texturizing agents, such as emulsifiers, stabilizers, thickeners, and bulking agents, are used in the food industry to modify the overall texture and mouth feel of foodstuffs. Thickeners, when added to the food mixture, increase the viscosity without modifying other food properties, while bulking agents increase the bulk of a food without affecting its nutritional value.These agents are used to add or modify the texture of food products by modifying the creaminess, thickness, viscosity, or by stabilizing foodstuffs structure. Citrus fruits and their by-products (such as peels and seed powders) have been studied as possible sources of texturizing agents due to their natural high pectin content and dietary fibre. Oranges are being used as texturizing agents in yogurts and/or ice creams, and lemon by-products are being used as thickening, texturizing, gelling, and stabilizing agents. citrus by-products have the added advantage of being rich in bioactive compounds, which possess nutritional and functional benefits.

Some studies also showed that incorporation of fiber from orange by-products into yogurts allowed for the manufacture of low-fat yogurts. The industrial processing of tomato leads to high amounts of unused matter (mostly peels and seeds), which are by products rich in lycopene and dietary fibre. These by-products have been incorporated in tomato sauce as a food texturizer, with sensorial tasting panels deeming it as acceptable. Whey proteins, obtained as a by-product of the dairy industry, have many functional properties including gelation, thickening, and water-holding capacity. Emulsifiers, molecules such as polysaccharides (e.g., gum arabic) or phospholipids (e.g., lecithins) with a surface activity capable of mixing and stabilizing two immiscible phases like water and oil, are largely used in food technologyEmulsifier additives can be obtained from a variety of food products (e.g., milk protein isolates) and by-products (e.g., okara). A potential emulsifier additive could be obtained from okara, a by-product obtained from soymilk production. Even though okara protein isolates had poor solubility, they exhibited other functional properties (emulsification, foaming, and binding properties) that were comparable to those of a commercial soy isolate, further demonstrating the potential use of these isolates as a food ingredient Overall, it is possible to see the potential of by-products derived food additives and potential new additives for application in the food industry. They are an integrated solution with low cost and reduced environmental impact capable of providing alternatives for an industry that relies heavily upon the chemical synthesis compounds. Thus, the use of by-products as a source of food additives stands out as an economically and environmentally conscious choice.

Food additives have an essential role in the current industry and consumption habits, as they not only make food products more appealing, but they increase their stability and inherent safety. Overall, food additives may be defined as compounds/extracts that are added to a food product in order to accomplish a specific technological goal but are not ingested as a food product themselves. The additive must not pose a safety concern for the consumers health (when ingested) while fulfilling a specific technological need that cannot be satisfied through other reasonable means. Microbiological processes can adversely affect the quality of food, leading to its spoilage. For this to occur, conditions that favor the growth and development of spoilage microorganisms must be met, such as bioavailable nutrients, favorable water activity, adequate pH value, presence/absence of oxygen, and redox potential. The term “food spoilage” is only applied if the changes in the foodstuffs due to the microorganisms’ potentially harmful metabolic products become recognizable, thus making the product unsafe for consumption and augmenting the risk of foodborne illness. However, not all microbiological change in food is considered harmful (for example, fermentation of grape juice in order to produce wine). Agro-food by-products, particularly fruit peels and seeds, have been regarded as a potential source of preservatives with several reports reporting on the potential antimicrobial activity of different fruit and vegetable by-product extracts, which could potentially be translated into an industrial application if the appropriate regulatory body gives a positive opinion. Oxidation is a not a process exclusive to the human body. It occurs in every living organism and biological system, such as food products. Food oxidation may result in altered flavor, color, nutritional value, and texture, as well as create toxic compounds .As such, antioxidant compounds are one of the most important conservation technologies used by the food industry with their main function being the prevention of oxidative induced degradation of foods, therefore allowing for extended shelf times. These additives help stabilize lipids as well as other compounds and can neutralize free radicals, avoiding a cascade of oxidative reactions.Since plants are one of the main sources of antioxidants compounds, agricultural by-products are among the most relevant potential sources of natural antioxidants that could be exploited for product quality preservation.

Texturizing agents, such as emulsifiers, stabilizers, thickeners, and bulking agents, are used in the food industry to modify the overall texture and mouth feel of foodstuffs. Thickeners, when added to the food mixture, increase the viscosity without modifying other food properties, while bulking agents increase the bulk of a food without affecting its nutritional value.These agents are used to add or modify the texture of food products by modifying the creaminess, thickness, viscosity, or by stabilizing foodstuffs structure. Citrus fruits and their by-products (such as peels and seed powders) have been studied as possible sources of texturizing agents due to their natural high pectin content and dietary fibre. Oranges are being used as texturizing agents in yogurts and/or ice creams, and lemon by-products are being used as thickening, texturizing, gelling, and stabilizing agents. citrus by-products have the added advantage of being rich in bioactive compounds, which possess nutritional and functional benefits. Some studies also showed that incorporation of fiber from orange by-products into yogurts allowed for the manufacture of low-fat yogurts. The industrial processing of tomato leads to high amounts of unused matter (mostly peels and seeds), which are by products rich in lycopene and dietary fibre. These by-products have been incorporated in tomato sauce as a food texturizer, with sensorial tasting panels deeming it as acceptable. Whey proteins, obtained as a by-product of the dairy industry, have many functional properties including gelation, thickening, and water-holding capacity. Emulsifiers, molecules such as polysaccharides (e.g., gum arabic) or phospholipids (e.g., lecithins) with a surface activity capable of mixing and stabilizing two immiscible phases like water and oil, are largely used in food technology.

Emulsifier additives can be obtained from a variety of food products (e.g., milk protein isolates) and by-products (e.g., okara). A potential emulsifier additive could be obtained from okara, a by-product obtained from soymilk production. Even though okara protein isolates had poor solubility, they exhibited other functional properties (emulsification, foaming, and binding properties) that were comparable to those of a commercial soy isolate, further demonstrating the potential use of these isolates as a food ingredient Overall, it is possible to see the potential of by-products derived food additives and potential new additives for application in the food industry. They are an integrated solution with low cost and reduced environmental impact capable of providing alternatives for an industry that relies heavily upon the chemical synthesis compounds. Thus, the use of by-products as a source of food additives stands out as an economically and environmentally conscious choice.