35.4 Film/Coating Materials from Marine Biowaste

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containing nitrates and phosphates can devastate the aquatic life by reducing the

oxygen levels and increasing the algal blooms [28]. Reutilization of these wastes

by turning into valuable compounds can provide many benefits and opportunity to

assist the environment.

35.4.1

Fish Processing By-products

Many fish processing industries generate a lot of wastes, nearly 50–80% of its total

production. Fish skin, scales, fins, and bones contain a huge amount of collagen

that serves as a structural protein. Collagen is used as emulsifying, stabilizing, and

gelling agent in food products. The frequent utilization of collagen and its derived

products made a demand for newer sources. It can be used for the gelatin production

by means of denaturation. Its biodegradability and fibril-forming nature made the

collagen as a biopolymer in the edible film production [28]. The only drawback of uti-

lizing the marine collagen is that it has inferior rheological properties, so that it has a

very limited application [29]. Utilization of fish gelatin results in good film-forming

properties and is an alternative to the synthetic packaging [30].

The composite film made with fish gelatin and a food grade chitosan is applied as

an aliphatic aroma compound barrier in food packaging [8]. It showed a less extrac-

tion of aroma compounds from the film due to their interaction with the amino

group of the gelatin which leads to covalent bond formation [31]. There are few

limitations for applying fish gelatin-based film, such as high-water solubility and

water vapor transmission rate. This can be controlled by adding any other compati-

ble hydrophobic component to the film-forming solution [30].

A film was made with protein concentrate extracted from Grouper fish

(Epinephelus marginatus) and plasticizers (sorbitol and glycerol). The mechanical

and barrier properties were evaluated and represented as the alternative utilization

for food material packaging [32]. The processing of tuna fish produces a large

amount of food waste having skin, bones, and fins. These can be valorized using

proteins, gelatins, collagen, and biofuel [5]. In one study [33], a biocomposite film

made up of cold fish skin gelatin and chitosan (incorporated with essential oil of

Origanum vulgare L.) was developed. Addition of essential oil directly resulted in

the reduction of its barrier, mechanical properties and transparency, but it showed

a positive result by inhibiting the Gram-positive bacteria (Staphylococcus aureus

and L. monocytogenes), so it is more suitable for antibacterial applications [8].

35.4.2

Crustacean By-Products

The processing of the sea foods, namely, crabs, shrimps, and lobsters, produce a

huge range of crustacean waste material which majorly includes chitin, proteins,

and carotenoids. Among these, chitin is extracted from the shell (exoskeleton) waste

of shrimp and is the most abundant polymer in the world [5]. Utilization of this

chitin and value addition will provide a way in the reduction of waste. Chitin is a

heteropolymer composed of (1-4)-linked-N-acetyl-β-D-glucosamine made in a linear

and complex form [17]. Because of its structure, chitin is insoluble and not directly