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Processing food waste for the production of platform chemicals 433

waste can be valorized through extraction of a valuable compound such as protein,
fibers, and phytochemicals. The Brewers’ spent grain which is the main solid waste
produced in large quantities by the beer industry containing up to 30% of the start-
ing malted grain. The Brewers’ spent yeast is also a by-product from Brewery
industry which also needs to be utilized (F˘ arca¸s et al., 2017).

19.2.1.6 Used cooking oil
Used cooking oil (UCO) waste after disposal after usage is creating concern to
environment globally. Waste cooking oil has the potential for the production of var-
ious products. It is estimated that 4.5 MMT of UCO may be available for biofuel
application in India. Since conventional biodiesel usually generates more NO x emis-
sion (NO x has about 300 times the GHG potential of CO 2 ), a low NO x emission bio-
diesel produced from UCO would add significantly more value from an
environmental perspective (Joshi et al., 2019).
The consumption of UCO poses adverse health effects. The use of waste cooking
oil was banned by the EU in 2000 as a feedstock because of its role in the contami-
nation of the food chain through intoxication causing disease because while frying,
several properties of the oil get altered (Nanda et al., 2019). Major nonvolatile by-
products of frying are total polar compounds such as dimeric fatty acids, triglycer-
ide monohydroperoxides, polymerized triglycerides, cyclic fatty acid monomers,
and aldehydic triglycerides (Haigh et al., 2014). Consumption of UCO can cause
diseases including hypertension, atherosclerosis, Alzheimer’s disease, and fatty
liver/hepatomegaly (Scientific India Magazine). UCO from starchy foods may con-
tain traces of acrylamide which is a potential carcinogen. UCO is an excellent sub-
stitute for virgin oil which is used in the production of biodiesel and biolubricants
(Chowdhury et al., 2013). Glycerol obtained as a by-product of the biodiesel pro-
cess is a precursor compound for the production of numerous other chemicals. At
the national level the Food Safety and Standards Authority of India has launched
RUCO (repurpose UCO) initiative in 2018 to enable collection and conversion of
conversion of UCO to biodiesel. Under this initiative, 64 companies at 101 loca-
tions have been identified to enable the collection of UCO (RUCO Repurpose Used
Cooking Oil).

19.2.2 Food-waste processing
Looking at the food waste over the world, food-waste processing must be done to
get high-valued compound at one end and to get social, environmental, and eco-
nomic benefits at other end. According to recent studies, India ranks seventh in
overall food wastage, while the Russian Federation tops the list (Dahiya et al.,
2018). Because of the mass production of food waste, environment also gets pol-
luted with the release of GHGs. Various approaches have been found in the litera-
ture for the food-waste management such as landfill, incineration, anaerobic
digestion, composting, fermentation, chemical methods and as animal feed which is
discussed next.