Duckweed, also known as water lens or bay root, is a flowering aquatic plant that floats on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands.
The plant is usually eaten in certain countries in the Southeast Asian region, such as Thailand, Cambodia, Myanmar and Laos. Locals often eat it in salads, soups, curries or omelettes.
The researchers investigated six species of duckweed, and specifically their characteristics—dry weight, protein, fat, starch content, and amino acid and fatty acid distributions.
The total protein content of the duckweeds was between 20-35 percent per dry weight for the investigated species, which is comparable to lupins, rapes, or peas—flour made from these are often recommended for vegetarian or vegan nutrition. Particularly, W. microscopia and W. hyalina were found to have the highest levels of amino acids.
Further, it was found that these plants contain stearidonic acid and alpha-linolenic acid—omega-3 fatty acids, and W. microscopia particularly has at least five times the amount of phytosterol content than in most other plant oils. Phytosterols have the capacity to lower plasma cholesterol and LDL (low-density lipoprotein).
Duckweed therefore can be used as a very nutritional alternative source of protein than meat, and the researchers suggest that possible applications include smoothies or gluten-free baked goods.
The aquatic plant at present has yet to be cultivated; currently it is simply being ‘harvested’ from bodies of water. There are however some initial experimental facilities in Israel and the Netherlands where it is produced on an industrial scale.