Flavonoid-Rich Extracts from Lemon and Orange By-Products: Microencapsulation and Application in Functional Cookies

Area of Science:

• Food Science and Technology
• Nutritional Biochemistry
• Sustainable Agriculture

Background:

• Citrus by-products are rich in bioactive compounds (BCs), especially flavonoids.
• Incorporating BCs into food offers health benefits and sustainability but faces stability and sensory challenges.
• Microencapsulation can protect BCs and improve their food matrix integration.

Purpose of the Study:

• To develop and assess functional cookies enriched with microencapsulated citrus peel flavonoid extracts.
• To evaluate the stability, flavonoid content, and sensory properties of the enriched cookies.
• To promote the valorization of citrus by-products for functional food applications.

Main Methods:

• Flavonoids were extracted from lemon and orange peels using a hydroethanolic solvent and analyzed via HPLC-DAD.
• Extracts were microencapsulated using sodium alginate and corn starch, forming thermally stable microbeads.
• Microencapsulated extracts were incorporated into gluten-free cookies, and flavonoid content and sensory attributes were evaluated.

Main Results:

• High total flavonoid content was found in orange (1960.1 mg/L) and lemon (845.7 mg/L) extracts.
• Microencapsulation achieved >85% flavonoid retention after 30 min at 230 °C.
• Enriched cookies contained 166.11–177.13 mg/100 g flavonoids, with no significant sensory differences from control cookies.

Conclusions:

• Microencapsulation effectively protects citrus flavonoid-rich extracts against heat, enabling their use in bakery products.
• The developed functional cookies provide a significant source of flavonoids and are sensorially acceptable.
• This study demonstrates a viable method for valorizing citrus by-products into sustainable, health-promoting food ingredients.