Owning to the increase in the world population as well as the consumer’s awareness on the
health benefits of consumption of fruits, the demand for both fresh and processed fruits has been increased.
The by-product and waste streams generated from fruit processing industries are extremely
diverse, owning mainly to different fruits varieties and the wide range of the processes employed towards
the production of the end fruit-based products. Due to the increasing production and processing
of fruits, disposal of waste and by-product streams has become a serious issue, since these materials
are prone to microbial spoilage. Also, the inappropriate waste management practices pose severe environmental
issues. Furthermore, the costs of drying and storage of fruit processing residues are economically
limiting factors hindering their further exploitation. Therefore, fruit processing by-products
such as peels, seeds and unused flesh are often utilized as fertilizers. On the other hand, plant residues
contain biomolecules such as vitamins, proteins, minerals, antioxidants and aromatic oil. Recovery of
bioactive compounds holds a great potential for their usage in food industry as functional ingredients
and nutraceuticals or in pharmaceutical and in cosmetic applications. So, valorization of plant fruit
processing by-products to high-value added compounds, constitute a promising alternative not only for
addressing fruit residues management issues but also leading to the production of functional food
products of high nutritional value, with several potential beneficial health effects. The aim of this paper
is to highlight current trends in addressing environmental issues caused by the production of high volumes
of specific categories of fruit processing waste streams by investigating their potential usage as
natural raw materials for the recovery of valuable bioactive compounds (such as polyphenols, dietary
fibers or aromatic oil). The extracted nutrients may be used in the industrial food sector for the production
of functional foods, nutraceuticals or even as health promoting natural pharmaceutical ingredients
or additives for the production of innovative enriched foods.
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Highlights:
• Fruit processing by product streams are rich in bioactive compounds.
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• Integration of fruit by-products and waste streams to value added products such as additives, unconventional
oil, bioactive compounds and novel functional products is a very interesting approach
regarding fruit processing residues exploitation.
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• Recovering of biomolecules from fruit residues by non-thermal processes could lead to the efficient
production of highly purified functional ingredients.
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• Negative-valued fruit processing residues could be recycled for the production of health promoting
value added products.
Microbial Upgrading of Acetate into Value-Added Products—Examining Microbial Diversity, Bioenergetic Constraints and Metabolic Engineering Approaches