Essential amino acids (EAAs) are amino acids that are necessary to build proteins in an organism. The source of complete EAAs are both animal and plant-based food. Essential amino acids in plant food Essential amino acids (EAAs) are the amino acids required by an organism for building proteins but which cannot be synthesized by the organism itself. As such it is essential that these amino acids be supplied by the organism's diet. In case of humans there are 9 EAAs: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
EAAs are provided in both animal and plant-based food. The EAAs in plants vary greatly due to the vast variation in the plant world and, in general, plants have much lower content of proteins than animal food. Some plant-based foods contain few or no EAAs, e.g. some sprouts, mango, pineapple, lime and melon. On the other hand, nuts, seeds, beans and peas contain EAAs in significant quantity. The following table shows the composition of EAAs in selected plant foods as well as recommended dietary allowances.(RDA) +EAAs content in plant foods(mg/100g) in comparison to RDA(for a 70-kg man (mg)) and chicken breast.1HistidineIsoleucineLeucineLysineMethionine
+ CysteinePhenylalanine
+ TyrosineThreonineTryptophanValineTotal EAAs contentRDA700140027302100105017501050280182012880Chicken, breast, raw83911041861216382117181009283116510963Soybeans, mature seeds, raw1097197133092706120236611766591202918332Cashew nuts, raw4567891472928755145968828710947928Pumpkin and squash seed, roasted7701265238812209222790985569155912468Beans, white, mature seeds, raw6501031186516036051921983277122210157Peas, mature seeds, raw58698316801771468166981315910359164Quinoa, raw4075048407665128604211675945071Wheat, durum32253393430350710383661765944773Rice, white, raw153281538235286565233753972763Tofu, raw, regular2214357134521377874021204463713Seaweed, spirulina, dried1080321049503020181253602970929351026841 1Chicken was chosen as it is the most eaten animal food and it has one of the highest amount of EAAs among animal-based foods.
Soybeans have the highest content of EAAs among the foods. Spirulina is a superior supplement containing the highest amount of EAAs. Another important factor is the composition of EAAs. As we can see the quantity of some EAAs is lower. For example, pumpkin seeds despite high total EAAs content have a low content of lysine. A good indication is to calculate the food sample that meets the WHO's requirement of EAAs intake. A table below shows the smallest sample food required to provide all EAAs according to the RDA for each individual EAA. +Amounts of sample foods required to provide a minimum amount of each EAA to equal the RDA (for a 70-kg man)ChickenSoybeansCashewPumpkin seedsBeansPeasQuinoaWheatRiceTofu156 g90 g226 g172 g173 g224 g325 g693 g893 g766 g Soybeans have the smallest sample food that provide complete protein, smaller than for several animal foods. Food samples for nuts, seeds, beans, and peas are bigger than one of chicken, and in case of rice, the sample is simply unpractical - the known fact is that cereals are not the main source of proteins.
External links
"In Vitro assessment of the nutritive value of expanded soybean meal for dairy cattle", Journal "Soy", MedlinePlus
References