Plant protein recovery technologies with focus on membranes

Frank Lipnizki1, Marilyn Rayner2 and Karolina Östbring2

1DEPARTMENT OF CHEMICAL ENGINEERING2DEPARTMENT OF FOOD TECHNOLOGY

LUND UNIVERSITY, SWEDEN

From raw plant material to edible proteins

Overview

• Conclusions and outlook

• Plant protein processig

• Membranes in protein processing

• Plant protein examples

Plant protein processingFuture - The protein shift

• Proteins are an essential part of the human diet.• Proteins of plant origin have a significantly lower

carbon footprint primarily due to absence of the environmental costs of inputs and generation of methane.

• A “protein shift” replacing animal based protein with proteins of plant origin is essential for a more sustainable food system.

• In 2016 USA reached “meat peak” at 97 kg per capita and for the first time the meat consumption decreased.

• In many Western countries the demand for plant proteins is increasing.

Plant protein processingProtein market

• Today’s global protein ingredients market is estimated to be 27.6 billion USD.

• The market share of animal proteins is around 62%, while 38% are currently plant proteins.

• The key animal proteins are whey, egg protein and gelatine.

• The key plant proteins are soy and wheat.

(Source: Global Industry Analyst 2012, Frost & Sullivan)

Plant protein processingExamples of plant proteins

• Soya protein• Wheat protein• Rapeseed protein • Sunflower protein• Pea protein • Quinoa protein

Plant protein processingBasic concept

Protein extraction/recovery

Protein purification

Protein concentration

Pea flakes

Pea protein powder

Protein utilisation

Plant protein productionExamples of extraction/decantation technologies

• Extraction e.g. alkaline extraction• Decantation• Precipitation• Screening

Vegetable protein productionExample of purification technologies

• Filtration• Centrifugation • Microfiltration• Ultrafiltration with diafiltration

Vegetable protein production Concentration technologies

• Evaporation• Spray drying• Ultrafiltration• Nanofiltration• Reverse osmosis

Vegetable protein production Water loop

• Microfiltration• Ultrafiltration• Nanofiltration• Reverse osmosis

Membranes in protein processingWhy???

• Proteins after extraction are often very diluted and require concentration before further processing.

• Proteins are general heat-sensitive and prefer gentle treatment.

• Membrane processes work excellent at low to medium concentrations.

• Membrane processes are gentle low temperature processes suitable for food applications.

Membranes in protein processing What is a membrane ?

UF and MF membrane

Membranes in protein processingMicrofiltration (MF)

• Pore size 0.1–1.0 µm• Typical operating pressure < 2 bar• Only suspended solids, bacteria and fat globules are rejected

Membranes in protein processingUltrafiltration (UF)

• Molecular weight cut-off (MWCO): 1,000–100,000 Dalton• Typical operating pressure 1–10 bar• Allows salts, sugars, organic acids and smaller peptides to pass• Rejects proteins, fats, enzymes and polysaccharides

Membranes in protein processingNanofiltration (NF)

• MgSO4 rejection > 99% • Typical operating pressure 5–35 bar• Allows monovalent ions to pass• Rejects divalent and larger ions and most organic components

Membranes in protein processingReverse Osmosis (RO)

• NaCl rejection > 95–96% • Typical operating pressure 15–75 bar• Concentration of liquids with low molecular compounds• Osmotic pressure of feed is important

Membranes in protein processingDiafiltration

Diafiltration is process to increase the purity of a product or to enhance product yield.• Addition of water (or recycled permeate) to the retentate to increase

transfer rate of impurities or product into the permeate

• Batch or continuous

• Additional membrane area required to remove added water

GöteneSweden, 1972UF of whey

Membranes in protein processing Past - How it started…..

Membranes in protein processing Today – The dairy protein refinery

Plant protein exampleRapeseed protein

• Rapeseed is the world's second largest cultivated oilseed.

• The primary product is vegetable oil (40 wt.%) and the remain is the protein-rich press cake as by-product (3 kg of rapeseeds generates 1 kg oil and 2 kg press cake).

• Rapeseed protein is comparable with soy protein in nutritional value and contains higher amounts of S-amino acids than many other plant proteins.

• The European Food and Safety Authority approved rapeseed protein isolated for human consumption in 2013.

Plant protein examplesRapeseed protein – An underutilized resource

3 kg rapseeds 1 kg rapeseed oil 2 kg rapeseed press cakeo 30% proteino excellent protein qualityo used as animal feedo 2 SEK/kg

meat 20% protein

Rape Rapeseed oil

Rapeseed press cake(30% protein/kg)

Plant protein-basedproducts

Prebiotics, building materials or pest control

Plant protein examplesRapeseed protein – A vision

“Fake-burger” and fries

Plant protein examplesRapeseed protein process

• First in lab scale– 100 g per batch– Parameter optimization– Onowledge exchange with industrial

partner

• Up-scaled to semi-industrial scale– 200 kg per batch

Plant protein examplesRapeseed protein – Production scale-up

• Texturized products(minced meat, filets, compare soyproducts)

• Dairy analogues(yoghurt etc.)

• Powder to enrichother foods

• Functional proteins (eg emulsifyingagents)

Plant protein examplesRapeseed protein – Products

Plant protein processingQuinoa protein

• Quinoa is a pseudo cereal native to the Andes, called the “mother grain” by the Incas and has been an important food crop for the last 5000 years.

• Quinoa grows at high altitudes (e.g. Bolivia, Chile) and in temperate climates (e.g. USA and Canada) and more recently in Denmark; Germany and Sweden.

• Quinoa is generally higher in protein than most grains and its protein content consists of high degrees of e.g. lysine and cystine.

Plant protein processingQuinoa protein processing

Conclusions• Various plant proteins are available to

enrich our human diet. • Concepts and technologies for

extracting/recovering plant proteins are available but require further optimisation.

• Rapeseed protein – a currently under utilised resource – can be an excellent plant source in Northern European countries.

• Quinoa is another potential protein-rich plant source.

The Future could be bright!!!

OutlookThree scenarios

Scenario A – Party ScenarioNew ways to reduce carbon dioxide and other climate gases in the atmosphere reversed the climate change. YIPPIE!

Scenario B - Protein ShiftDrastic changes in life style including a diet which significantly reduced meat intake and more plant-based foods in the Monday-Friday menu.

Scenario C – Do Not Act

The Team

Karolina Östbring, Postdoc, Expert in isolation of plant proteins

Ingegerd Sjöholm, Docent, Expert in processning of plants

Marilyn Rayner, Professor, Expert in food processing

Ia Rosenlind, Adjunkt,Expert in food chemistry,

Acknowledgements

Pufendorf Theme “Protein Shift” 2018/19

Thank you for your attention