Functional Ingredients and Additives from Lemon by-Products and Their Applications in Food Preservation: A Review

Abstract

Citrus trees are among the most abundant fruit trees in the world, with an annual production of around 124 million tonnes. Lemons and limes are among the most significant contributors, producing nearly 16 million tonnes per year. The processing and consumption of citrus fruits generates a significant amount of waste, including peels, pulp, seeds, and pomace, which represents about 50% of the fresh fruit. Citrus limon (C. limon) by-products are composed of significant amounts of bioactive compounds, such as phenolic compounds, carotenoids, vitamins, essential oils, and fibres, which give them nutritional value and health benefits such as antimicrobial and antioxidant properties. These by-products, which are typically discarded as waste in the environment, can be explored to produce new functional ingredients, a desirable approach from a circular economy perspective. The present review systematically summarizes the potential high-biological-value components extracted from by-products to achieve a zero-waste goal, focusing on the recovery of three main fractions: essential oils, phenolic compounds, and dietary fibres, present in C. limon by-products, and their applications in food preservation.

Formulation and Characterization of Non-Toxic, Antimicrobial, and Alcohol-Free Hand Sanitizer Nanoemulgel Based on Lemon Peel Extract

“…The concentration of each phenolic compound can vary depending on the lemon variety. Nonetheless, the obtained concentrations are in accordance with the values described in the literature for lemon extracts [53,58]. Furthermore, several of the identified compounds, such as naringenin, hesperidin, ellagic acid, and coumaric acid, are commonly found in Citrus species and have been researched for their antioxidant, anti-inflammatory, antimicrobial, and antiviral activities [31,[59][60][61].…”

“…Citrus limon peel is highly rich in phenolic compounds, which have been studied for their antioxidant and antimicrobial capacities [8,53]. Therefore, the release profile of phenolic content from LE and LN formulations was analyzed.…”

Citrus limon Essential Oil: Chemical Composition and Selected Biological Properties Focusing on the Antimicrobial (In Vitro, In Situ), Antibiofilm, Insecticidal Activity and Preservative Effect against Salmonella enterica Inoculated in Carrot

“…Fresh produce deteriorates by approximately 50% during harvesting, handling, storage, and transport. EOs are applied to whole and freshly cut fruits and vegetables and are essential in preventing this condition [ 19 ]. Lemon EO for use in vegetable products was developed by Sessa et al [ 20 ].…”

Citrus By-Products as a Valuable Source of Biologically Active Compounds with Promising Pharmaceutical, Biological and Biomedical Potential

“…Numerous studies have considered citrus extracts as a natural source of bioactive components exhibiting beneficial activities, including antioxidant [ 15 , 16 , 17 , 18 , 19 ], antibacterial [ 16 , 18 , 19 , 20 , 21 ], antidiabetic [ 17 , 22 , 23 , 24 ], neuroprotective [ 22 , 25 , 26 , 27 ], and anti-inflammatory [ 28 , 29 , 30 , 31 ] activities, as well as antitumor [ 32 , 33 , 34 , 35 ] potential. Also, citrus by-products are considered a valuable source of phytochemicals (such as d -limonene, essential oils, phenolic acids, carotenoids, vitamins, minerals, and flavonoids), which, isolated or in the form of mixtures/extracts, could exhibit versatile biological activities especially beneficial for the food industry [ 36 , 37 , 38 ]. Citrus-based essential oils exhibit significant antimicrobial activity against foodborne bacteria and also antioxidant activity to prevent the effects of oxidation; hence, citrus-based essential oils could act as natural preservatives [ 39 , 40 , 41 ].…”