Cecilia Wittbjer of Parabel describes the beneficial characteristics of the water lentil as a source of functional ingredients and plant protein.
Water lentils are relative newcomers to the plant protein ingredients world. The Latin name of this crop is Lemnaceae and it is also commonly called duckweed. They have small floating leaves growing on top of still water all around the world and are now being cultivated in large open hydroponic ponds. The crop needs sunshine and a warm climate to grow in an optimal way but it is a fairly sturdy plant that can survive for long periods at the bottom of lakes in colder climates, surfacing again when the sun comes out. An interesting attribute of this crop is that the plant doubles its mass in 24 hours, which means a daily harvest and a yield many times higher than other crops. Another advantage of this plant is its nutritional profile – especially the high concentration of protein. It has a complete and balanced amino acid profile and contains many other important macro‐ and micro‐nutrients.
Cultivation of water lentils
Parabel, a company based in Florida, USA, has been growing water lentils for seven years in various locations around the world to show the crop’s potential as a solution to food security and sustainability. The company ran growth trials in South America, East Africa and in Asia for at least one year at each location to validate the technology in different parts of the world. The results showed that it is a very scalable crop, capable of growing in many locations and supplying vast amounts of plant protein to the food industry. The water lentil species are locally sourced in each location to make sure that they grow well under the specific climatic conditions and that there is no disruption to the local ecosystem. The plants are grown with minimal quantities of mineral nutrients and there is no need for pesticides.
Currently, Parabel is undertaking a growth trial to evaluate whether the crop can be grown at close to optimal yields even under harsh climates such as in the desert. This trial will assess the ability of the crop to provide food security for countries that struggle to produce their own food and are having to import food and feed at high cost to themselves and the environment. This has become an even more pressing issue during the COVID‐19 pandemic, since supply chains have been strained.
The company is also in the later stages of constructing the second commercial production facility in Florida, USA. It has been manufacturing and supplying the US food industry with protein ingredients for over 3 years from its first farm and the second facility will expand its capability to meet demand from the food industry for novel plant protein ingredients. The new facility will commence operation in 2020, producing 3,000 tons of protein ingredients per annum. LENTEIN® is the brand name for Parabel’s line of products extracted from the water lentils. This represents a range of protein ingredients from whole food protein to protein concentrates and isolates. The concentrate contains 65% protein and has foaming, emulsion capabilities and high water solubility. The isolate containing 85% crude protein has more functional properties and can, for example, be used as an egg‐white replacer.
The hydroponic farm transforms marginal, non‐arable land into productive areas. There is no conflict with other crops and there is no need for chemicals or pesticides in the system. The processing recycles 98% of the water and there is no leakage of nutrients into nearby areas. In fact, the water use per kilo is very low compared to that of animal proteins and also other plant proteins, such as soy or pea.
The CO2 emissions are low due to the minimal processing requirements. The water lentils are taken out of the water, cleaned, washed and the protein is then separated mechanically from the fibre through proprietary technology and then finally dried to produce the plant protein product.
The nutritional profile of the water lentil extract shows higher levels of essential amino acids and BCAA’s than other plant proteins and it has application as a protein booster in many types of product. In addition to an amino acid profile similar to that of animal proteins, it is also highly digestible with a digestibility of 1.0 and a PDCAAS (protein digestibility–corrected amino acid score) of 1.0. It has been incorporated into smoothies and ready to mix beverages as well as dry mix goods, such as pasta, chips and crackers. There is also a green version with a vibrant green colour, which is stable at temperatures used in baking.
The hydroponic farm transforms marginal, non‐arable land into productive areas.
Recently the presence of plant‐based vitamin B12 was discovered in the water lentil crop. This vitamin is very important for people following vegan diets, for those with gastrointestinal disorders and for some in the elderly population, who are deficient in this vitamin.
There are four different forms of vitamin B12, or cobalamin: methylcobalamin, adenosylcobalamin, hydroxycobalamin and cyanocobalamin. Two of these, methylcobalamin and adenosylcobalamin, are the bioactive forms which are readily digested by the human body1. The other two forms must be converted into one of these bioactive forms before being available to the body, making them less efficient as a source of the vitamin.
In addition, cyanocobalamin, which is the most commonly found vitamin B12 supplement in stores, is synthetically derived from fermented bacteria. A study by Paul et al. concluded that there is significant evidence that synthetic cobalamin is not as effective in converting MMA (methylmalonyl‐CoA) into an important enzyme (succinyl‐CoA) in the process that produces energy within the body.
The study showed that there was a 13% increase in cobalamin stored in the liver and tissues when taking methylcobalamin compared to cyanocobalamin. Three human studies have also shown a lower retention of vitamin B12 when taking cyanocobalamin compared to the other three forms of cobalamin2.Studies on vitamin B12 from algae, such as Spirulina, have discovered that this is only a vitamin B12 analogue – or pseudo‐vitamin – which blocks the binding of natural vitamin B12. Nori contains natural vitamin B12, but studies have confirmed that 65% of it was a pseudo‐vitamin3.
Water lentils can be grown at higher yields than other crops and in many areas where food – at least protein rich foods – cannot be grown.
Vitamin B12 present in the water lentil extract has been shown to mainly consist of the bioactive forms methylcobalamin and adenosylcobalamin. Third party testing by a laboratory that holds ISO/ IEC 17025 certification using the Mass Spectrometry (LC‐MSMS) test, a precise and reliable method, measured the amount of the vitamin present and the various forms of cobalamin in the crop. The test indicated that adenosylcobalamin was present at 86%, methylcobalamin at 13% and hydroxycobalamin was also detected at 1%.
Parabel is working with several institutions to undertake clinical studies to verify the bioavailability and the potential to reverse deficiency in humans, through evaluating MMA and homocysteine levels in volunteers within the next year.
Other nutritional characteristics
In the last few years product launches in the plant‐based category have been on the rise. This is due to the increasing interest in ethically produced products and eating less meat. A large number of people (often known as flexitarians) are trying to reduce their intake of meat. Water lentils are a source of sustainable plant‐based protein functional ingredients which can be used for both meat and dairy alternatives.
During COVID times there has also been an increase in products targeting immunity as well as general health and wellness. Water lentils contain Omega 3 ALA (alpha‐linolenic acid), as well as chlorophyll, vitamin A, lutein and zeaxanthin.
LENTEIN received the FDA no objections letter in the USA in 2018. Health Canada recognises water lentils as a food, as do multiple other countries around the world; it has been eaten in South East Asia for many years and is listed in the Chinese Pharmacopeia. Parabel is in the later stages of negotiation with EFSA (European Food Safety Authority) regarding approvals to enter the European market.
Water lentils can be grown at higher yields than other crops and in many areas where food – at least protein rich foods – cannot be grown. They contain a wide range of valuable nutrients which address the key market drivers – health and sustainability.In a world where the middle class, urbanisation and fast food is growing, health is paramount. The water lentil offers a source of plant‐based protein that meets many of the needs of today’s consumers.