alternative food sources

Alternative Food Sources

Alexander Golberg, PhDPorter School of Environmental Studiesagolberg@gmail.com

July 2017

We will talk about

• Demand

• Supply

• Energy and Food

• Quality vs Energy

• Human energy requirements: how much food we need?

• Agriculture and Farming

• Modern food systems: gains and efficiencies – Food subsidies

• Seaweeds, Insects and Cultures Meat

• Novel Food challenges

Man-material balance

Ton/person/year

+0

6

5.1 Gases

Waste

Solid waste0.1

0.8

Resources

+6

89

19 Gases

Sewage

3

61

Solid waste

Resources

Where do the materials we use today come from?

https://farmingfirst.org/Post2015-Food

https://farmingfirst.org/Post2015-Food

https://www.forbes.com 6 Key Investment Themes For The Next Decade

1870–73

Energy Sources and Basal Metabolism

• Must consume three classes of nutrients (available in plant and animal food)

• Including organic compounds, vitamins and minerals.

• Absorbed in small intestine and are redistributed by blood to reproduce, grow, be active and adapt.

Energy yielding macronutrients

• Carbohydrates

• Proteins

• Lipids.

• Consumed at 10 (proteins and lipids) and 100 (carbohydrates) g/day.

Energy yielding micronutrients

• K ad Na (2.5 g/day)

• B-12, 3 µg/day

• But must for a healthy lifestyle.

• Deficiencies of Ca, P, Mg, and Zn impede normal growth, inadequate vitamin intakes disrupt the functioning of essential processes leading to gastrointestinal disturbances (folacinshortage) and epithelial hemorrhaging with low ascorbic acid.

Quality is important

• Food is not only a matter of sufficient quantities

• Most of the Earth carbohydrate ( cellulose and lignin) are cannot be digested by humans)

• Digestible carbohydrates are ingested as polysaccharides (starch) and simple sugars.

• Simple sugars include (fructose, glucose) and disaccharides :• Lactose (natural milk)

• Sucrose (refined sugar)

• Maltose (enzymatic degradation product of starch)

Energy values are determined as residuals after determination of proteins, lipids, water and ash.

Energy content of food

• Measured after complete combustion yielding CO2 and H2O

• Part of ingested energy is lost in feces and intestinal gases (H2 and CH4) produced by microbial fermentation of unabsorbed carbohydrates in the colon.

• A small part of digestible energy is lost through skin and urine

• Additional fraction is lost through heat (microbial fermentation and dietary induced thermogenesis)

• A very small fraction is lost to thermogenesis due to hormones, drugs or effects of cold and stimulants, leaving energy for maintenance that sustain basal metabolism and is available for physical activity.

Energy content of food

• Carbohydrates 17.3 kJ/g.

• Proteins 23 kJ/kg

• Fats 39 kJ/kg

Carbohydrates

• Dominant energizers of human evolution

• Staple cereals ( rice, wheat, corn, millet), tubers ( potatoes, cassava), leguminous grains (beans, soybeans, peas, lentils) and sugar refined from cane and beets.

• Complex carbohydrates are preferable to the simple varieties especially when consumed as whole seeds and whole grain ( 5-100g/day).

The Importance of Dietary Carbohydrate in Human

Evolution. Hardy et al. 2015

https://rosemarycottageclinic.wordpress.com/category/evolution/

Proteins and Fats

• Highest concentration of plant proteins is found in legumes (soybeans), cereals and nuts.

• Fats are present in high quantity in plant seeds, fatty meat, fish and dairy.

• The average consumption of fat in preindustrial societies was very limited. Now they constitute ~ 40% of food intake in rich nations.

Dietary proteins• Human growth is impossible without essential amino acid (9 in infants and

8 in adults)

• Amino acids contain 15%-18% N, 16% is commonly used

• Amino acids are precursors for structural molecules as proteins in muscles and enzymes, hormones and neurotransmitters, and antibodies and metabolically active compounds.

• Some N is used to replace secreted proteins caused by reutilization of compounds, excretions of N, shedding of skin, and cutting of hair and nails.

• Complete proteins with all share of essential amino acids are available only in foods of animal origin and mushrooms.

• Plant proteins are incomplete and need additions of some amino acids. Cereal grains are deficient in lysine and leguminous seeds in methionine and cysteine.

Lipids

• Contain two essential fatty acids: linoleic acid and alpha- linolenicacid.

• These must be digested to become precursors of prostaglandins and parts of cell membranes.

• Food lipids also carry fat soluble vitamins A,D,E and K.

Ethanol

• Gross energy 29.3 kJ/g

• Can be utilized only in the liver at hourly rates of 0.1 g/kg body (190kJ/h or 53W for a 65 kg person)

Human Energy Requirements

• In adults: energy required (intakes) to maintain body weight and composition, support desirable level of physical activity and long-term health.

• In children: + growth needs

• In pregnant women: + deposition of new tissues

• In lactating women: + production of milk

• Basal Metabolic Rate is leading, activities for work and leisure are the rest.

• Physical activity level (PAL)=TEE/BMR. TEE=total energy requirement

• Metabolic equivalent ~ cost of sitting resting metabolic rate (RMR)

Total Energy Expenditure

• In adults:

• 12.5 MJ/d (male)

• 9.2 MJ/d (female)

Dietary recommendations

• First published in 1941, tenth edition in 1989

• From 1997 dietary reference intakes ( not only to prevent nutrients deficiency but also to prevent chronic disease).

• DRI • carbohydrates is 130g/d,

• protein 56g/d (males) and 46g/d (females)

• 2 essential fatty acid.

Uncertainties

Coastal Kaul tribe were 27% (males) and 13% (females) high than their expected basal metabolic rate or

about 2.4MJ/d for man and 2.9MJ for women less than in a highland villages.

Unexplainable by differences in methodology, body weights, food availability and work.

1940-1983? 2017?

Why one person live on half the calories of another?

Humans are very flexible converters of food energy, able to respond with altered metabolic efficiencies to different diets, environmental conditions, specific tasks and health states.

How much? For What? In what context?

Cultural preferences and social expectations.

Elsie Widdowson (1906-2000)

Agriculture

• Is periodically strenuous energy investment combating tendency towards weedy disorder and producing orderly harvests.

• Ecologist might note the emphasis on the separation of crops and grains as key crops.

• An anthropologist will focus on inevitability of collective participation in seasonally demanding labor altering with periods of extended rest.

• Rindos (1984): “Such a complex process has no single cause, only history with many interdependent interactions”.

• Important to reject agriculture as invention and a notion of agricultural revolution.

Farming?

• New tools, cereal processing, sedentism and storage habits were not necessary prerequisites.

• The earliest conformation of pounding and grinding wild cereals for baking comes from Upper Paleolithic site (19,500 B.C.E) in Israel, 12,000 years before domestication of cereals.

• Multiple examples of complex societies with houses and storage based on hunting and gathering and an opposite, thousands of years of agriculture with no permanent settlements.

• Many foraging societies coexisted side by side with agriculturalists, farming had not universal appeal.

Framing rise

• Why it arose at the same time on three continents between 10000 and 5000 years ago is a mystery and will stay so.

• Environmental explanation: Paleolithic agriculture was impossible due to dry climate and low CO2 levels. Neolithic agriculture was mandatory. But it diminishes returns in gathering and hunting, brought by slow growth of foraging populations, extension of cultivation techniques and slow adoption of variety of cultivation practices.

• Cultural factors: farming fosters association a desirable goal for our sociable species. It also makes easer to have larger families and facilitates warefare.

Farming and energy

• Many early field harvest had net energy returns smaller than gathering.

• Quality was higher in cultivars

• The transition from foraging to farming was facilitated by a complex energetic, nutrition and social factors, but further development of agriculture was driven by pure energy imperatives.

• As a particular food production system reaches its limit, the affected population can • migrate, • stay and stabilize; • stay and decline; or • adopt more productive subsistence.

Practices shifts

• The shifts require high energy inputs, so even with higher food production density, the return can be low.

• Higher edible energy flux will support a larger population

• A natural tendency is to postpone the switch as long as a less intensive arrangement will do.

• Tel Abu Hureyara (Syria) hunting remained a critical source of food for 1000 years after the beginning of plant domestication.

Farming and Innovation

• These steps recover more of the site potential photosynthesis and support more people per ha of land.

• But require more energy to prepare the site and make tools.

• Large parts of energy inputs are long-term, intensive cropping required planning, storage, trading- civilization complexification, promoting • innovation, • specialization, • independence and • exchange of goods and techniques.

Plowing ->draft animals

Grains processing-> mastering water and winds energy

Distance distribution-> wind, water, animals.

Iron and tools->melting with charcoal.

Fertilizers

• By 2000, global average for N, P and K applications were 53 kg/ha, 9 kg/ha and 12 kg/ha.

• Rice fields in Jiangsu and Huanrequired 500kg N, 50 kg P, and 100 kg K /ha.

Modern Food Systems: Gains, Costs, Efficiencies. • The Iowa field receives 30 GJ/ha in direct and indirect energy

subsidies, but the solar flux during the 150 days between planting and harvesting in 1000-fold higher ( 20 TJ/ha).

• But without electricity and fossil fuels fluxes, only a tiny amount of this free energy will be converted to biomass.

• This subsidies also improved the quality of nutrition.

Between 1900 (low level fertilization and basic mechanization) and 2000, the world cultivated area grew by 80%-100%,

but energy harvested in edible food expended sixfold.

Direct result of 85-fold increase in energy subsidies per harvested hectare.

Food Energy Availability

• In 1900 1 ha of cultivated land could feed 1.5 people, edible harvest prorated to less than 10 MJ/day. Daily requirement is 9 MJ per capita.

• Modern farming increased the number of people to 4 people with modern diet and 6 with diet of 1900 (almost no meat).

• The best performances are better. China 8-15 people per heavily fertilized land.

• National data on food availability is published in FAO food balance sheets.

• Daily per capita excess in the USA is 15 MJ/day, EU 8.5 MJ/day and <8.5MJ/day in sub-Saharan Africa. At 2000, Chinese and Japanese supplies equaled to 12.5 MJ/day.

Food waste and undernourishment

• US surveys indicate adult male consumption 10.3 MJ/day and female 6.9 MJ/day (diet among many females). Average 8.4 MJ/day. Below average requirement of 9 MJ/day. Because of sedentary lifestyle, diet, and unreported.

• 50% gap with the availability ( 15 MJ/day). Food looses. Same picture in EU.

• But, there are 852 million (2005) with 815 million in poor countries and 220 million in India, who are undernourished because of internal conflicts, distribution inequalities, poor agriculture and other reasons

National balances of farming

• Australia and New Zealand (2-3 GJ/ha)

• Netherlands and Israel (70-80 GJ/ha)

• Special case of China which has 1.5 crops/ha, 50% irrigation of all land, and intensive fertilization. 165 kg nitrogen /ha (USA 60 kg N per ha). Half of all nitrogen in China’s food come from inorganic fertilizers.

• China’s population depends for survival on external energy subsidies, US population could be fed from the abundant farmland without any synthetic fertilizer.

• 2/5 people get proteins thanks to Haber-Bosch synthesis. But in rich countries the fertilizer helps to provide rich diets with plenty of animal foods and surplus food for export, in low-income countries it prevents wide-spread malnutrition.

Should we reduce food subsidy ratios?• Do we eat grapes because of their energy or because of their taste?

• Minimizing energy inputs would transfer all systems to tubers, but they have very few proteins and spoil faster than grains.

G7 leaders are calling to phase out fossil fuels by 2100

Can we do without subsidized agriculture?

• Nitrogen losses are 50%, and commonly 60-70% of applied nutrients. Asian irrigation systems efficiency can be doubled.

• Matching the power of US tractors with horses would require 250million heads, 10 times more that a record of 1918.

• 300 million ha (twice of USA arable land) will be needed to feed these animals.

• Doing without insecticides will reduce the harvest by 10-50%.

100 YEARS OF AGRICULTURAL CHANGE: SOME TRENDS AND FIGURES RELATED TO AGROBIODIVERSITY (FAO)

• Since the 1900s, some 75 percent of plant genetic diversity has been lostas farmers worldwide have left their multiple local varieties and landracesfor genetically uniform, high-yielding varieties.

• 30 percent of livestock breeds are at risk of extinction; six breeds are losteach month.

• Today, 75 percent of the world’s food is generated from only 12 plants andfive animal species.

• Of the 4 % of the 250 000 to 300 000 known edible plant species, only 150to 200 are used by humans. Only three - rice, maize and wheat -contribute nearly 60 percent of calories and proteins obtained by humansfrom plants.

• Animals provide some 30 percent of human requirements for food andagriculture and 12 percent of the world’s population live almost entirely onproducts from ruminants.

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Foreaging

Modern agriculture

Traditional agriculture

Pastoralism

Shifting farming

Foreaging

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Traditional agriculture

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Shifting farming

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60% of arable land potential is

in 13 countries

Population

Carrying capacity of environment

Population

Carrying capacity of environment

Human population growth

tool use

fossil fuels

agriculture

?

Next Step Could Be Offshore

IMAGE: Nori cultivation in Fujian, China. Photograph by

Wong Chi Keung, via People and Planet.

World Seaweed Production: CEVA

5 orders of magnitude

less than agriculture

Macroalgal Biorefinery

5-24% proteins in 2054

Alternative protein

http://4ento.com/2015/01/26/insects-as-a-protein-alternative/

Or Next Step Could Be in the Lab?-Cultured meat

Winston Churchill suggested in 1931:

"We shall escape the absurdity of growing a whole

chicken in order to eat the breast or wing, by growing

these parts separately under a suitable medium

Bhat, Zuhaib Fayaz, and Hina Fayaz. 2011.

“Prospectus of Cultured Meat—Advancing

Meat Alternatives.” Journal of Food Science

and Technology 48 (2): 125–40.

doi:10.1007/s13197-010-0198-7.

https://www.youtube.com/watch?v=3LKsSEbSrUQ

What is needed

• Cell source

• Scaffold

• Bioreactor

• Culture media and growth factors. What is media?

• A lot of locally trained personal.

AllergyToxicity

Anti nutritional

Potential concerns

Job security

Ladics et al. Regulatory Toxicology and Pharmacology 54 (2009) S2–S6