Table 2.

Active and intelligent biodegradable films and their food applications.

Active Biodegradable Films
Biopolymer	Active Compound	Food Application	References
Soy protein isolate	Montmorillonite (0.5%wt) + clove essential oil (0.5%v)	Bluefin tuna filets	[253]
Chitosan and Corn starch	Lemon essential oil (1–3%wt) and grapefruit seed extract (1–3%wt)	Blueberries conservation simulating transport and commercial conditions	[182]
Corn starch	Green synthesized AgNPs in situ (143 ppm)	Cheese preservation	[173]
Tapioca starch	Grape pomace extracts (8% v/v) and cellulose nanocrystals (10% v/v)	Ready to eat chicken meats	[254]
PLA	Commercial nanoparticles: TiO2 (3%wt); (2%wt) nano-TiO2 + (1%wt) nano-Ag	Cottage cheese preservation	[255]
Curdlan + PVA	Thyme essential oil (1–2%wt)	Chilled pork meat preservation	[256]
Whey protein	Oregano and garlic essential oils (2%wt)	Kasar cheese	[257]
Chitosan-Cassava TPS bilayer films	Oregano and or cinnamon leaf essential oils (0.25%wt)	Sliced pork meat	[258]
Gelatin/Gellan gum	Red radish anthocyanins 5, 10, 15, and 20 mg/100 mL	Milk and fish quality	[259]
Zein	Laurel or rosemary leaves extracts (1–10%)	Cheese slices	[260]
Chitosan	Propionic acid	Pastry dough	[168]
Intelligent Biodegradable Films
Function	Intelligent System and Innovative Characteristic	Food Application	References
Temperature sensor	A passive RFID tag modified with a copper-doped ionic liquid	Fresh products, for the identification of cold chain failures	[245]
Temperature abuse indicator	Au nanoparticles included in alginate hydrogel. Biobased, food safe, cost-effective, time sensible	Fresh products	[261]
Thermal insulation	Commercial pale-yellow carnauba wax. Biobased and biodegradable insulator	Beverages	[262]
pH-based freshness indicator	Biodegradable films containing anthocyanins from different sources. Real-time monitoring of food freshness.	Fresh products: cheese, yogurt, fish, pork, shrimp, and beef	[250,263,264,265,266,267]
pH sensitive	Natural compounds showing color changes with pH in biodegradable films	Fish and seafood products	[85,212,268]
CO2 detector	Labels containing natural (anthocyanins) or commercial (bromothymol blue and tetrabutyl-ammonium) dyes.	Fermented products such as kimchi	[269]
Oxygen indicator	UV-light activated oxygen sensitive biobased film with methyl blue indicator	Suggested for food products packed in modified atmosphere	[270]
Hydrogen sulfide indicator	Biobased films containing silver nanoparticles (detect up to 0.81 μmole H2S) or ferrous sulfate (detect 100 ppm H2S) and had a fast response (3 min).	Meat and meat products. Chicken breast and silver carp	[85,271]
Humidity indicator	Colorimetric-based sensor on photonic cellulose nanocrystals	Suggested for pharmaceutical products, cereals, and grain seeds storage	[272]