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What constitutes protein?
What is protein?
Protein is a sequence of amino acids
Indispensable amino acids – cannot be made by body* must be provided by the body
Dispensable amino acids – can be made by the body*
What is protein?
Various bonds and chains combine to give higher levels of organisation
Differences in functional properties and bioavailability of the proteins
Tertiary structure Quaternary structure
What is protein?
native form
denaturation
HeatPressureAgitationSalts pH
Increased digestibility
Loss of solubility
Why do we eat protein?
1. Nutrition• Energy • Amino acids• Growth & Repair
Nutrition
Total protein content
Indispensable (essential) amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
Bioavailability refers to how easy it is for the body to digest, absorb and use a protein in its metabolic processes. Animal proteins are known to have high bioavailability.
Animal Protein
Why do we eat protein?
1. Nutrition• Energy • Amino acids• Growth & Repair
3. FUNCTIONAL PROPERTIES…..
“any property of a substance, besides the nutritional ones, that affects its utilisation”
2. Organoleptic• Texture• Appearance• Flavour • Smell
What are we currently eating?
Global Food supply: the world’s need for protein. Mike Boland. Riddet Institute
Global protein supply
Is this sustainable?
• In 2011, 90% of global fish stocks were fully or over exploited
• Just 3 crops – maize (corn), wheat and rice account for 50% of the world’s consumption of calories and plant protein
• Water footprint for beef is 6 x greater than that of pulses
• 15% of all human caused greenhouse gas emissions is caused by livestock production
• 90% of global soy crops is produced in just 3 countries; USA, Brazil, Argentina – the supply of which is at risk due to climate change
Forum for the Future: The Future of Protein, Protein Challenge 2040
• Soybean cultivation has been a driver for deforestation in South America
Is this sustainable?
Meat
Milk
FAO Predictions
Year
Global Food supply: the world’s need for protein. Mike Boland. Riddet Institute
Why do we need sustainable protein?
Dairy free
Gluten free
Satiety
Why should we eat sustainable proteins?
Protein matched mealsMushrooms or Ground Beef
Greater “fullness”More fibre No effect on overall energy intake
19 year old study showed diets rich in vegetable proteins had a 35% lower risk of Type 2 Diabetes
By replacing 5g of meat protein with vegetable protein risk could reduce by 18%
Publications…..
Plant AND ProteinInsect vs. Dairy
Sustainable Proteins
Plant Protein
• Grains, seeds, nuts and pulses• Concentrates, isolates, hydrolysates
• Protein content of soy bean and lupin 45–50%
- May not contain all the essential amino acids – methionine (pulses)
- Anti-nutrients
Soybean Protein: Success Story• High protein digestibility score
comparable to animal proteins • Tofu, soymilk, tempeh, miso meat & dairy extenders and analogs
Microbial Protein
• Derived from microorganisms –yeasts, fungi
• Concentrates or processed to fibres/meat analogs
• Mycoprotein – singled celled protein + All essential amino acids + High digestibility+ Low in fat + High in fibre
Sustainable Proteins
Future Gazing
Algal Protein
• Marine plants - Seaweeds and Microalgae
• Seaweeds are complex multicellular organisms that grow in salt water or a marine environment
• Microalgae are single celled organisms that can grow in a range of environmental conditions
• Cultivated or Harvested
+ Up to 47% protein by weight
+ Nutritionally similar to plant protein
− Potential accumulation of heavy metals, high levels of iodine, and contaminants such as dioxins and pesticides
Microalgae biomass as an alternative ingredient in cookies: Sensory, physical and chemical properties, antioxidant activity and in vitro digestibility, In Algal Research, Volume 26, 2017, Pages 161-171.
Protein valorisation
Insect Protein
• Resource efficient • Fresh or dried whole insects, flours, extracts
+ Protein content between 35 – 61%, richer in protein than beans, lentils and soybeans
+ Protein digestibility 77 – 98% similar to eggs, beef and casein
+ Unsaturated fat, no cholesterol, Iron, Calcium, Zinc & B Vitamins
− Lysine and Tryptophan deficient (insect dependent)
− Allergenic – crustaceans, dust mites
Current legislation: Novel Foods
• A novel food is defined as a food that does not have a significant history of consumption within the EU before 15 May 1997
• If a food was commercialised in at least one member state before this date it can be marketed elsewhere in the EU without Novel Foods Regulation
• Application
• Substantially equivalent
• EU 2015/2283
• Covers the consumption of whole insects and their parts
• 1st January 2018 EU Commission will establish a Union List of novel foods authorised to be placed on the market within the Union
• For inclusion on the Union list a food
• Must not pose a safety risk to human health
• Must not mislead the consumer
• Where the food is intended to replace another food, it does not differ from that food in a way that would be a nutritional disadvantage
US Edible Insect Market Prediction
Lab grown proteins
• Cultured meat, cell-cultured meat or clean meat• Animal product produced following cell isolation and
identification, cell culture and tissue engineering
+ Foodborne illness reduction + Much reduced environmental impact + Control over content and type of fat
− 10-20 years til market ready (currently expensive)− Different eating quality (process dependent)− Consumer acceptance – GM Link
Where are we?
Traditional sources of protein
Sustainable Proteins Research at UoN
3. FUNCTIONAL PROPERTIES…..
“any property of a substance, besides the nutritional ones, that affects its utilisation”
Protein sources include:
Insects
Marine plants
Plant incl. underutilised crops
Proteins recovered from food waste
Functional properties of the protein are utilised in creation of typical
food microstructure e.g. emulsion, foams and gels.
Stability assessed in complex food matrices during and post-
processing
Variety of chemical and physical methods of protein extraction are
being explored followed by protein characterisation
Protein characterisation includes amino acid content, protein content,
charge, size and structure, interfacial properties such as surface
activity and interfacial rheology.
80 μm
Functional Properties: Emulsification and Foaming
Air
Oil
Oil in water emulsion Oil drops in water
FoamAir bubbles in water
Functional Properties: Thickening & Gelation
Native protein Denatured protein
GelEntrapped water
Protein aggregation
The challenge
Functional Properties of Insect Protein
Emulsifying ability of mealworm protein >whey protein
Mealworm protein Whey protein
Gould, J. and Wolf, B. (2017) Interfacial and emulsifying properties of mealworm protein at the oil/water interface. https://doi.org/10.1016/j.foodhyd.2017.09.018
Foaming ability of mealworm protein
Potential application in Egg-Free Cakes
Gelation of mealworm protein
Mealworm larvae protein
Contained in Chitin exoskeleton:+ 49% Protein,+ 35% Lipid, + 2 mg/ 100 g Iron, + 16.9 mg / 100 g Calcium,
Novel materials & processes
High pressure processingElectrical and ultrasonic fields
Protein valourisation from spent grain and spent bread
Food product applications
No additional protein Potato Protein Pea Protein
Reduced sugar cakes – addition of plant protein to aid aeration
Fat Free Ice CreamDairy Free Ice Cream
Alternative protein ice cream mix assessed during processing
operations
Apart from being GREEN….Why use Sustainable Proteins?
• Added functionality
• Added nutritional value
• Dietary requirements
• Processing capabilities
• Taste
• Texture
• Cost
Considerations….
Considerations….
People will starve to death rather than attempt to eat food that is;
• Unsafe – allergens, anti-nutrients
• Unpalatable – off flavours, disgust factor
• Unfamiliar
• Lower nutritional profile
Raw material
Structure Function
Amino acid sequence
Processing Processing
