Food Waste Anaerobic Digestion Explained eBook pdf

Anaerobic Digestion of
Food Waste
A Wikipedia Compilation

Anaerobic Digestion of Food Waste
Food waste or food loss is food that is discarded or lost or uneaten. The two
are similar, but have key distinctions within their definitions. The causes of food
waste or loss are numerous, and occur at the stages of production,
processing, retailing and consumption.
As of 2013, half of all food is wasted worldwide, according to the British
Institution of Mechanical Engineers (IME). Loss and wastage occurs at all
stages of the food supply chain or value chain. In low-income countries, most
loss occurs during production, while in developed countries much food – about
100 kilograms (220 lb) per person per year – is wasted at the consumption
stage.
Contents
1Definition1.1United Nations1.2European Union1.3United
States2Causes2.1Production2.2Food
processing2.3Retail2.4Consumption3Extent3.1Global extent3.2Individual
countries3.2.1New Zealand3.2.2Singapore3.2.3United Kingdom3.2.4United
States4Reductionand disposal4.1Landfills and greenhouse gases4.2Municipal
collection4.3Animal feed4.4Composting4.5Anaerobic digestion4.6Commercial
liquid food waste4.7Agricultural food waste4.8Food Waste
Recovery6References7Bibliography8Further reading9External links
Definitions of Food Waste

The definition of waste is a contentious subject, often defined on a situational
basis; this also applies to food waste. Professional bodies, including
international organizations, state governments and secretariats may use their
own definitions.
Definitions of food waste vary, among other things, in what food waste consists
of, how it is produced, and where or what it is discarded from or generated by.
Definitions also vary because certain groups do not consider (or have
traditionally not considered) food waste to be a waste material, due to its
applications. Some definitions of what food waste consists of are based on
other waste definitions (e.g. agricultural waste) and which materials do not
meet their definitions.
United Nations
A 2011 study by the Swedish Institute for Food and Biotechnology (SIK) on
behalf of Food and Agriculture Organization of the United Nations (FAO),
Global Food Losses and Food Waste, distinguishes between "food loss" and
"food waste", and provides figures for both:
Food loss measures the decrease in edible food mass (excluding inedible parts
and seed) "throughout the part of the supply chain that specifically leads to
edible food for human consumption", that is, loss at the production, postharvest
and processing stages. This definition of loss includes biomass originally meant
for human consumption but eventually used for some other purpose, such as
fuel or animal feed.Food waste is food loss occurring during the retail and final
consumption stages due to the behavior of retailers and consumers – that is,
the throwing away of food.European Union

In the European Union, food waste was defined as "any food substance, raw
or cooked, which is discarded, or intended or required to be discarded" since
1975 until 2000 when the old directive was repealed by Directive 2008/98/EC,
which has no specific definition of food waste. The directive, 75/442/EEC,
containing this definition was amended in 1991 (91/156) with the addition of
"categories of waste" (Annex I) and the omission of any reference to national
law.
In July 2014, the European Commission has announced its targets for the
circular economy, waste management and provided a "food waste" definition
as "food (including inedible parts) lost from the food supply chain, not including
food diverted to material uses such as bio-based products, animal feed, or
sent for redistribution" (i.e. food donation). Concurrently, all Member States of
the European Union shall establish frameworks to collect and report levels of
food waste across all sectors in a comparable way. The latest data are
requested to develop national food waste prevention plans, aimed to reach the
objective to reduce food waste by at least 30% between 1 January 2017 and
31 December 2025. To enable the process, the Commission shall adopt
implementing acts by 31 December 2017 in order to establish uniform
conditions for monitoring the implementation of food waste prevention
measures taken by Member States of the EU.
United States
The United States Environmental Protection Agency defines food waste for the
United States as "uneaten food and food preparation wastes from residences
and commercial establishments such as grocery stores, restaurants, and
produce stands, institutional cafeterias and kitchens, and industrial sources like
employee lunchrooms". The states remain free to define food waste differently
for their purposes, though many choose not to.

Causes of Food Waste
Food Waste During Production
In developing and developed countries which operate either commercial or
industrial agriculture, food waste can occur at most stages of the food industry
and in significant amounts. In subsistence agriculture, the amounts of food
waste are unknown, but are likely to be insignificant by comparison, due to the
limited stages at which waste can occur, and given that food is grown for
projected need as opposed to a global marketplace demand. Nevertheless, on-
farm losses in storage in developing countries, particularly in African countries,
can be high although the exact nature of such losses is much debated.

Research into the food industry of the United States, whose food supply is the
most diverse and abundant of any country in the world, found food waste
occurring at the beginning of food production. From planting, crops can be
subjected to pest infestations and severe weather, which cause losses before
harvest. Since natural forces (e.g. temperature and precipitation) remain the
primary drivers of crop growth, losses from these can be experienced by all
forms of outdoor agriculture. The use of machinery in harvesting can cause
waste, as harvesters may be unable to discern between ripe and immature
crops, or collect only part of a crop. Economic factors, such as regulations and
standards for quality and appearance, also cause food waste; farmers often
harvest selectively, preferring to leave crops not to standard in the field (where
they can be used as fertilizer or animal feed), since they would otherwise be
discarded later. In urban areas, fruit and nut trees often go unharvested
because people either don't realize that the fruit is edible or they fear that it is
contaminated, despite research which shows that urban fruit is safe to
consume.
Food Waste During Food processing
Food waste continues in the post-harvest stage, but the amounts of post-
harvest loss involved are relatively unknown and difficult to estimate.
Regardless, the variety of factors that contribute to food waste, both
biological/environmental and socio-economical, would limit the usefulness and
reliability of general figures.

In storage, considerable quantitative losses can be attributed to pests and
micro-organisms. This is a particular problem for countries that experience a
combination of heat (around 30 °C) and ambient humidity (between 70 and 90
per cent), as such conditions encourage the reproduction of insect pests and
micro-organisms. Losses in the nutritional value, caloric value and edibility of
crops, by extremes of temperature, humidity or the action of micro-organisms,
also account for food waste; these "qualitative losses" are more difficult to
assess than quantitative ones. Further losses are generated in the handling of
food and by shrinkage in weight or volume.
Some of the food waste produced by processing can be difficult to reduce
without affecting the quality of the finished product. Food safety regulations are
able to claim foods which contradict standards before they reach markets.
Although this can conflict with efforts to reuse food waste (such as in animal
feed), safety regulations are in place to ensure the health of the consumer;
they are vitally important, especially in the processing of foodstuffs of animal
origin (e.g. meat and dairy products), as contaminated products from these
sources can lead to and are associated with microbiologicaland chemical
hazards.
Food Waste During Food Retailing
Packaging protects food from damage during its transportation from farms and
factories via warehouses to retailing, as well as preserving its freshness upon
arrival. Although it avoids considerable food waste, packaging can compromise
efforts to reduce food waste in other ways, such as by contaminating waste
that could be used for animal feedstocks.

Retail stores can throw away large quantities of food. Usually, this consists of
items that have reached their either their best before, sell-by or use-by dates.
Food that passed the best before, and sell-by date, and even some food that
passed the use-by date is still edible at the time of disposal, but stores have
widely varying policies to handle the excess food. Some stores put effort into
preventing access to poor or homeless people, while others work with
charitable organizations to distribute food. Retailers also contribute to waste as
a result of their contractual arrangements with suppliers. Failure to supply
agreed quantities renders farmers or processors liable to have their contracts
cancelled. As a consequence, they plan to produce more than actually required
to meet the contract, to have a margin of error. Surplus production is often
simply disposed.
Retailers usually have strict cosmetic standards for produce, and if fruits or
vegetables are misshapen or superficially bruised, they are often not put on the
shelf. In the United States, an estimated six billion pounds of produce is wasted
each year because of its appearance. In a study done in 2009, it was
estimated that nearly 20 to 40 percent of fruit and vegetables in the UK alone
are rejected before they even reach retailers, as a result of high cosmetic
standards.

The fish industry also contributes to the annual amount of food waste because
of cosmetic standards that the fish are held up to. Nearly "2.3 million tonnes of
fish (are) discarded in the North Atlantic and the North Sea each year."
Approximately 40 to 60 percent of "all fish caught in Europe in is discarded -
either because they are the wrong size or species." Addressing this, there are
many campaigns focused on raising retailer and consumer awareness about
food that fails to meet certain standards for appearance.
Food Waste During Consumption
Empirical evidence show that drivers of consumer food waste, even in a low-
middle income context, include: (1) stocking too much food; (2) over-preparing
or not cooking it properly (e.g. burning food); (3) leaving food on dishes after
meals or not willing to consume leftovers; and (4) decaying of prepared food
after long or inappropriate storage. Excessive purchasing, over-preparation
and unwillingness to consume leftovers are some of the main antecedents of
food waste. As author Gustavo Porpino states, “they are embedded in cultural
practices such as hospitality, the good mother identity, taste for abundance,
and food seen as wealth”.
Extent of Food Waste
Global extent

The 2011 SIK study estimated the total of global food loss and waste to
around one third of the edible parts of food produced for human consumption,
amounting to about 1.3 billion tons per year. As the following table shows,
industrialized and developing countries differ substantially. In developing
countries, it is estimated that 400-500 calories per day per person are going to
waste, while in developed countries 1,500 calories per day per person are
wasted. In the former, more than 40% of losses occur at the postharvest and
processing stages, while in the latter, more than 40% of losses occur at the
retail and consumer levels. The total food waste by consumers in industrialized
countries (222 million tons) is almost equal to the entire food production in sub-
Saharan Africa (230 million tons).
Food loss and waste per person per year Total At the production and retail
stages By consumers

Europe 280 kg (620 lb) 190 kg (420 lb) 90 kg (200 lb)North America and
Oceania 295 kg (650 lb) 185 kg (408 lb) 110 kg (240 lb)Industrialized Asia 240
kg (530 lb) 160 kg (350 lb) 80 kg (180 lb)sub-Saharan Africa 160 kg (350 lb)
155 kg (342 lb) 5 kg (11 lb)North Africa, West and Central Asia 215 kg (474 lb)
180 kg (400 lb) 35 kg (77 lb)South and Southeast Asia 125 kg (276 lb) 110 kg
(240 lb) 15 kg (33 lb)Latin America 225 kg (496 lb) 200 kg (440 lb) 25 kg (55
lb)A 2013 report from the British Institution of Mechanical Engineers (IME)
likewise estimated that 30–50% (or 1.2–2 billion tonnes) of all food produced
remains uneaten.
Food Waste Generation in Individual countries
New Zealand
Main article: Food waste in New ZealandSingapore
In Singapore, 788,600 tonnes of food was wasted in 2014. Of that, 101,400
tonnes were recycled. Since Singapore has limited agriculture ability, the
country spent about S$14.8 billion (US$10.6 billion) on importing food in 2014.
US$1.4 billion of it ends up being wasted, or 13 percent.
United Kingdom
Main article: Food waste in the United KingdomIn the UK, 6.7 million tonnes per
year of wasted food (purchased and edible food which is discarded) amounts
to a cost of £10.2 billion each year. This represents costs of £250 to £400 a
year per household.
United States

In a study done by National Geographic in 2014, Elizabeth Royte indicated
more than 30 percent of food in the United States, valued at $162 billion
annually, isn't eaten. The University of Arizona conducted a study in 2004,
which indicated that 14 to 15% of United States edible food is untouched or
unopened, amounting to $43 billion worth of discarded, but edible, food.
Another survey, by the Cornell University Food and Brand Lab, found that 93
percent of respondents acknowledged buying foods they never used.
Food Waste Reduction and Disposal
Response to the problem of food waste at all social levels has varied hugely,
including campaigns from advisory and environmental groups, and concentrated
media attention on the subject.
As alternatives to landfill, food waste can be composted to produce soil and
fertilizer, fed to animals, or used to produce energy or fuel. Limiting food
wastage has seen the adoption of former World War I and World War II
slogans by antiwaste groups such as WRAP.One way of dealing with food
waste is to reduce its creation. Consumers can reduce spoilage by planning
their food shopping, avoiding potentially wasteful spontaneous purchases, and
storing foods properly. Another potential solution is for "smart packaging" which
would indicate when food is spoiled more precisely than expiration dates
currently do, for example with temperature-sensitive ink, plastic that changes
color when exposed to oxygen, or gels that change color with time.

An initiative in Curitiba, Brazil called Cambio Verde allows farmers to provide
surplus produce (produce they would otherwise discard due to too low prices)
to people that bring glass and metal to recycling facilities (to encourage further
waste reduction). In Europe, the Food Surplus Entrepreneurs Network (FSE
Network), coordinates a network of social businesses and nonprofit initiatives
with the goal to spread best practices to increase the use of surplus food and
reduction of food waste.
The Problem of Food Waste in Landfills and
Greenhouse Gases
Dumping food waste in a landfill causes odour as it decomposes, attracts flies
and vermin, and has the potential to add biological oxygen demand (BOD) to
the leachate. The European Union Landfill Directive and Waste Regulations,
like regulations in other countries enjoin diverting organic wastes away from
landfill disposal for these reasons. Starting in 2015, organic waste from New
York City restaurants will be banned from landfills.
In countries such as the United States and the United Kingdom, food scraps
constitute around 19% of the waste dumped in landfills, where it ends up
rotting and producing methane, a greenhouse gas.

In a study done on Italy in 2014, it was estimated that food waste from 'farm to
fork' emits nearly 4 million tons of CO2. The country produces 186,000 tons of
oil equivalent annually.
Methane, or CH4, is the second most prevalent greenhouse gas that is
released into the air, also produced by landfills in the U.S. Although methane
spends less time in the atmosphere (12 years) than CO2, it's more efficient at
trapping radiation. It is 25 times greater to impact climate change than CO2 in
a 100-year period. Humans accounts over 60% of methane emissions globally.
Food Waste Municipal Collection
In areas where waste collection is a public function, food waste is usually
managed by the same governmental organization as other waste collection.
Most food waste is combined with general waste at the source. Separate
collections, also known as source-separated organics, have the advantage that
food wastes can be disposed of in ways not applicable to other wastes. In the
United States, companies find higher and better uses for large commercial
generators of food and beverage waste.

From the end of the 19th century through the middle of the 20th century, many
municipalities collected food waste (called "garbage" as opposed to "trash")
separately. This was typically disinfected by steaming and fed to pigs, either
on private farms or in municipal piggeries.
Separate curbside collection of food waste is now being revived in some areas.
To keep collection costs down and raise the rate of food waste segregation,
some local authorities, especially in Europe, have introduced "alternate weekly
collections" of biodegradable waste (including, e.g., garden waste), which
enable a wider range of recyclable materials to be collected at reasonable
cost, and improve their collection rates. However, they result in a two-week
wait before the waste will be collected. The criticism is that particularly during
hot weather, food waste rots and stinks, and attracts vermin. Waste container
design is therefore essential to making such operations feasible.
Use of Food Waste as Animal Feed
Large quantities of fish, meat, dairy and grain are discarded at a global scale
annually, when they can be used for things other than human consumption. The
feeding of food scraps to animals is, historically, the most common way of
dealing with household food waste. The animals turn roughly two thirds of their
ingested food into gas or fecal waste, while the last third is digested and
repurposed as meat or dairy products. There are also different ways of
growing produce and feeding livestock that could ultimately reduce waste.

It is now widely believed by scientists that the domestication of the dog was
related to food scraps. Indeed, some believe that dogs "self-domesticated" by
following around hunter-gatherer bands in order to eat their scraps. In many
preindustrial societies, domestic dogs perform (or performed) valuable service
to their human owners in exchange for scraps of meat. For example, sled dogs
in the Arctic, or herding dogs and livestock guardian dogs in Europe. Modern-
day pet dogs are also often fed table scraps. In fact, taking leftovers home
from a restaurant is often called a doggy bag.

One of the common animals to be fed household scraps is swine, in which case
the food scraps are often called slop. A study done in 2009 suggests
approximately 20 times more CO2 can be saved by feeding food waste to
pigs, instead of allowing it to go through anaerobic digestion. Some European
laws restrict the amount and type of scraps that can be fed to pigs. However,
in countries such as Japan, South Korea and Taiwan, it is encouraged and
furthermore mandatory to feed certain food waste to pigs.
The amount of bread and other cereal products discarded in UK households,
has been indicated to be enough to "lift 30 million of the world's hungry people
out of malnourishment." These grains, wasted for different reasons (including,
e.g., over production) could have otherwise been used to feed chickens.
Chickens have traditionally been given mixtures of waste grains and milling by-
products in a mixture called chicken scratch. As well, giving table scraps to
backyard chickens is a large part of that movement's claim to sustainability,
though not all backyard chicken growers recommend it.
Composting of Food Waste
Inevitable waste: peels of potato,onion, lemon, tangerine, banana,kiwi,
eggFood waste can be biodegraded by composting, and reused to fertilize soil.
By redistributing nutrients and high microbial populations, compost reduces
water runoff and soil erosion by enhancing rainfall penetration, which has been
shown to reduce the loss of sediment, nutrients, and pesticide losses to
streams by 75-95%.
Vermicomposting is the practise of feeding scraps to worms who produce
fertilized soil as a byproduct.

Food waste can be composted at home, avoiding central collection entirely,
and many local authorities have schemes to provide subsidised composting bin
systems. However, the proportion of the population willing to dispose of their
food waste in that way may be limited.[citation needed]
Anaerobic digestion of Food Waste
Anaerobic digestion produces both useful gaseous products and a solid fibrous
"compostable" material. Anaerobic digestion plants can provide energy from
waste by burning the methane created from food and other organic wastes to
generate electricity, defraying the plants' costs and reducing greenhouse gas
emissions.
Food waste coming through the sanitary sewers from garbage disposal units is
treated along with other sewage and contributes to sludge.
Commercial liquid food waste

Commercially, food waste in the form of wastewater coming from commercial
kitchens’ sinks, dishwashers and floor drains is collected in holding tanks called
grease interceptors to minimize flow to the sewer system. This often foul-
smelling waste contains both organic and inorganic waste (chemical cleaners,
etc.) and may also contain hazardous hydrogen sulfide gases. It is referred to
as fats, oils, and grease (FOG) waste or more commonly "brown grease"
(versus "yellow grease", which is fryer oil that is easily collected and processed
into biodiesel) and is an overwhelming problem, especially in the USA, for the
aging sewer systems. Per the US EPA, sanitary sewer overflows also occur
due to the improper discharge of FOGs to the collection system. Overflows
discharge 3 billion US gallons (11,000,000 m3) - 10 billion US gallons
(38,000,000 m3) of untreated wastewater annually into local waterways, and
up to 3,700 illnesses annually are due to exposure to contamination from
sanitary sewer overflows into recreational waters.
In US metropolitan areas, the brown grease is taken by pumpers or grease-
hauling trucks to wastewater treatment plants, where they are charged to
dump it. In other areas, it may be taken to a landfill or it may be illegally
dumped somewhere unknown, to avoid charges. This unmonitored disposal
process is not only harmful for our environment and our health, but it also hurts
businesses which have no idea where their business waste ends up, or indeed
how much liquid waste is in their grease interceptors at any point in time,
leaving them vulnerable to illegal dumping into their own grease traps or
interceptors. Some companies now market computerized monitoring services
along with in situ bioremediation, which produces byproducts of CO2 and gray
water that can safely flow into sewer systems. Other new technologies offer ex
situ treatment to process brown grease into some form of transportation fuel.
This may not be as environmentally friendly as in situ treatment, since it still
requires vehicles to pump and transport the brown grease waste to the plants.

Estimating how much brown grease food waste is produced annually is difficult,
but in the US alone, number is thought to be in the billions of gallons. In 2009,
the city of San Francisco stated it produces about 10 million US gallons
(38,000 m3) of brown grease a year. It is starting the first city-wide project in
the US to recycle brown grease into biodiesel and other fuels.
Agricultural food waste
Nearly all global produce, eaten or disposed of is grown using irrigated water.
The irrigated water is taken from rivers, lakes, and wells by farmers amounting
to roughly 675 litres. If the food goes uneaten, the water is ultimately wasted.
To put it into perspective, this wasted water would "be enough for the domestic
needs (at 200 litres per person per day) of 9 billion people."
Food Waste Recovery

Food wastes are undesirable for the food industry in terms of sustainability and
environmental impact, but perhaps more important in view of high disposal
costs. For this reason, they have been considered as a matter of treatment,
minimization and prevention for more than 40 years. Nowadays, food wastes
account as a source for the recovery of valuable compounds and deal with the
prospect of feeding population in the 21st century. Perspectives originate from
the enormous amounts of food related materials that are discharged worldwide
and the existing technologies, which promise not only the recovery but also the
sustainability of high added-value ingredients inside food chain.
________________________________________
This eBook is a compiled and heading edited version of the following wikipedia
page.https://en.wikipedia.org/wiki/Food_waste
This ebook uses material from the above Wikipedia article, which is released
under the Creative Commons Attribution-ShareAlike 3.0 Unported License
(If you want to view the references cited in the original Wikipedia page above,
which we have removed for reduced distraction during reading, follow the
above link.)
You can give away this ebook, and also add it to to your own website, but you
must not charge for it.
All Memes added to this ebook, can be found at: http://anaerobic-digestion-
news.blogspot.co.uk
________________________________________

For more eBooks like this one visit our website at:
www.AnaerobicDigestion.com - Click Here!

Food Waste Anaerobic Digestion Explained eBook pdf

Recommended

Recommended

More Related Content

Viewers also liked

Viewers also liked (10)

Recently uploaded

Recently uploaded (20)

Food Waste Anaerobic Digestion Explained eBook pdf