27.2 Biovalorization of Organic Waste

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generated from agriculture, forestry, fisheries, aquaculture, animal feed, and biolog-

ical processes are used for a variety of applications such as aquaculture and chemical

processing. In addition, decay products can re-enter the nutrient and biological

cycle. Extraction of oleochemicals through recycling of vegetable and/or animal fats

and recycling of bioplastics also could be foreseen as possible outputs of CBE [4, 5].

27.2

Biovalorization of Organic Waste

In scientific literature, food loss and waste are classified as products for human con-

sumption that are subsequently discharged, lost, degraded, contaminated, and ulti-

mately is a source of pollution. Food content discharge occurs along the entire food

supply chain and includes all sectors of waste management right from its collection

to disposal [6]. The issue of sustainable waste management is an important chal-

lenge that faces our society today. Solutions to this pressing problem should achieve

socioeconomic and environmental benefits. Conversion of food waste into a source

of renewable energy has transformed the food sector to a potentially feasible car-

bon economy [7]. Toward achieving the aims of CBE, two of the options available

for biovalorization include (i) extraction of bioactives and economically important

compounds from the wastes generated and (ii) utilization of the wastes to generate

biofuels that are alternatives to the existing fossil fuels.

27.2.1

Extraction of Bioactives

Food wastes contain a combination of carbohydrates, lipids, and proteins. Depend-

ing on the source of these wastes, and their chemical nature, these can be used as

the starting material for the production of different bioactive compounds. Some of

the wastes and their potential reuse include

a. Fruit and vegetable processing wastes: These wastes could be used for

(i) extraction of polymers like pectin, cellulose, etc., from fruit and vegetable

processing wastes [8] and (ii) for the production of natural colorants, including

anthocyanins, flavonoids, etc. [9, 10].

b. Dairy wastes: These wastes can be used for the production of a variety of com-

pounds, including antioxidants, antimicrobials, etc. [11].

c. Meat and poultry processing wastes: These wastes can be used for the extrac-

tion of collagen, gelatin, polypeptides, etc. [9].

d. Sea food wastes: These can be used for protein isolates and hydrolysates [9].

e. Dairy industry wastes: These can be used for the isolation of casein, lactose,

and whey protein isolates [9].

27.2.2

Bioenergy Production

The components of wastes, i.e. carbohydrates, proteins, and lipids, can be considered

as potential sources of different biofuels. The biofuels can be produced using biopro-

cesses or thermochemical processes depending on the composition of the food waste

[12, 13].