Water lentils, commonly known as duckweed and classified by science as a member of the Lemnaceae plant family, are neither a lentil nor a legume. An important food source for waterfowl in the wild, these plants grow naturally in stagnant or slow-moving bodies of freshwater, as well as in wetlands. The popularity of water lentils has recently spread throughout the world as a superfood for people. However, other industries have also eyed the plant as potential animal feed and for biofuel production. 

The species used most for human consumption are Wolffia arrhiza and Wolffia globose. Known by the name “Khai-Nam'' and consumed by people in Laos, Myanmar, Thailand, and elsewhere in Southeast Asia, these nutrient-rich plants also appear in Asian herbal remedies. Though not part of Western cuisine, the plant has become popular in recent years, as it offers a high-quality source of plant proteins for healthy vegan and vegetarian diets. Including the recent rise in water lentil protein powder supplements, the plant is becoming an increasingly popular health food due to the ease with which it grows and its high nutritional value. 

Water Lentils: Protein Powder Superfood & More

The increase in global demand for water lentils’ protein powder supplements has introduced the plant into Western diets, not only as a meat alternative but also for use in other applications like sports nutrition, health snacks, plant-based milks, and even baked goods. Requiring minimal processing, many companies have looked into ways to produce water lentils sustainably. Protein powders and other nutrient-rich supplements made from the plant have also piqued the interest of nutraceutical, animal feed, biofuel, and food processing industries. 

Plant proteins offer a number of health benefits, though most do not contain essential amino acids that are mainly found in meats. The water lentil is an exception. 

Water lentils are:

  • allergen-friendly,
  • digestive-system compatible, 
  • Nutrient-rich, and 
  • the only bioavailable and plant-based source for vitamin B12

One of the most difficult nutrients for vegans to source is vitamin B12, which human bodies cannot naturally produce, as it otherwise only appears naturally in foods of animal origin, including dairy products, eggs, fish, meat, and poultry. In a solely plant-based diet, water lentils offer a way for vegans to keep healthy while also adding plant-based protein with all nine of the amino acids the human body cannot produce on its own. 

Other ways in which water lentils can support human health include:

  • aiding the normal function of nerve cells,
  • boosting energy,
  • forming of red blood cells, 
  • helping DNA synthesis, and
  • offering relief for those with poor digestion, intestinal damage, leaky gut, nutrient deficiencies, and immune reactions. 

In addition to Vitamin B12 and a full spectrum of protein amino acids, water lentils also contain various vitamins, minerals, healthy fats like omega 3, antioxidants, and dietary fiber. 

A Sustainable Food Source

According to a United Nations report titled “How to Feed the World in 2050,” the world will require 70% more food by 2050. Water lentils would support this need, as all they require to grow is water and sunshine. Additionally, water lentils only require their weight in water, meaning they require no additional water beside the substrate in which they grow. 

Considering the following, it takes:

  • 1900 lbs. (approximately 862 kg) to produce a pound (approximately 454 g) of almonds or
  • 4300-15,000 lbs. (approximately 1950-6804 kg) to produce a pound (approximately 454 g) of meat from chickens, sheep, or cattle. 

Meanwhile, it takes a mere 705 lbs. (approximately 320 kg) of water to grow a pound (approximately 454 g) of lentils. Further, because water lentils are grown in water, growers can recycle nearly all of the water it takes to grow them.  Given all these factors, these remarkable plants could be one of the planet’s most sustainable foods when it comes to water use.

Growing Water Lentils for Food Supplements 

Reproducing asexually, water lentils can double in biomass every 24-48 hours. Given their natural environment in Southeast Asia, water lentils grow best in warm, fresh, and nutrient-rich water. When growing water lentils for protein powders, food supplements, and other uses, the whole plant gets used. As the plants can double in mass in as little as 24 hours, it also makes growing water lentils incredibly efficient and allows harvesting of plants daily.

Given how they grow in the wild, they are perfect for growing hydroponically. When it comes to the large-scale growing of water lentils, currently this happens on sizable aquafarms, often in greenhouses, to better control environmental factors to prevent contamination by toxins or heavy metals. Since water lentils are grown in very controlled environments, they also do not require pesticides. 

Fast-growing water lentil strains can produce about .7 oz. (20 gr) when dried per 10.8 square feet (one square meter) farmed. This equates annually to around 1.4 million lbs. (about 635 kg) per almost every two and a half acres (one hectare), which is about fifty times the yield from corn. Water lentils can even be farmed vertically, growing them in water-filled trays stacked one on top of another, keeping the space needed to a minimum. This is an ideal situation for urban farmers. 

Protein Powder & Other Products Made from Water Lentils

Processing water lentils is a streamlined process that avoids harsh treatment and chemical extractions to keep the crop’s nutritional value intact. For the Western palette, finely grinding it into a greenish powder gives it a better mouthfeel and makes it more versatile, allowing food processors to utilize it in various ways. This “gentle” processing means nutrients stay active, providing more benefit to consumers. 

Water lentils made into protein powder offer an ingredient that can adapt to be used in a wide variety of foodstuffs. Raw water lentils are often first ground into a fine green powder. The food industry can then formulate various dry foods like crackers, cereal bars or clusters, chips, snack mixes, and other edible products. Water lentil protein powder on its own mixes well with liquids, so it can additionally be made into sports drinks, protein shakes, or just combined with water as a meal replacement.  

Which Machine Do I Need?

Prater Industry Air Classifiers: Processing Water Lentil Protein Powder 

Prater’s machinery allows nutraceutical and health food processing facilities to handle the main part of hydroponically-grown plants from growers and grind them into specific particulate ranges. Its machinery and systems can grind this raw material down to a micron range that gives it a more palatable texture for Western consumers and better mouthfeel. The raw material can be broken down into water lentil protein powder and altered to meet any specialized particle size ranges required. 

As water lentils need to be ground into a very fine powder, Prater’s air classifying mills offer a means to achieve this, including for clients who require large throughputs. To produce even larger quantities, however, Prater can build a custom-built system to offer greater efficiency.  Prater's MAC Air Classifier in parallel with its M Series Fine Grinder allows milling the material to occur separately from air classification.