How do you determine the quality of a protein? PDCAAS
When it comes to protein quality you should always consider its digestibility and amino acid profile. Nowadays, the most accurate and widely used measurement of these factors is the PDCAAS (protein digestibility corrected amino acid score index). In general, plant-based proteins have a lower index (usually around 0,7) than animal ones (usually above 0,9). This tells us that animal proteins have an amino acid profile that is closer to what our bodies need than the protein in plants and also that our bodies have an easier time digesting and making use of animal protein. This does not mean you cannot cover your protein needs purely by plants. You just have to know how.
Tofu? No. Tempeh? Yes
The most popular vegan and vegetarian source of protein is soy, without a doubt. Unfortunately, there are several issues with that. Though the PDCAAS of soy is way above average for a plant source (above 0,9), it is usually consumed as Tofu. Tofu is made out of raw or sometimes just soaked soy beans. This means a lot of the anti-nutrients such as lectins or phytic acid are still present. It is also good to know, most of the soy available today is genetically modified.
If you want soy, go for Tempeh which contains fermented soy beans. Fermentation makes soy much less threatening for your digestion. But still, don’t make it your only protein source, overconsumption of soy can cause hormone imbalances because it can affect estrogen production.
Germinated hemp seed protein is the best
The hemp seed stands out among all plant food choices because it is the only plant protein source that has all the amino acids our bodies use. Look for germinated or fermented hemp seed proteins as the best option, they digest well and have a great amino acid score. There are very little downsides to it except that the high quality one could be relatively expensive.
Soaked nuts and seeds
Both nuts and seeds are a great option. Firstly, they are very rich in protein, secondly, they bring a lot of healthy fats, and finally, they are full of minerals. The only problem is they also contain plenty of anti-nutrients and nutrient inhibitors just like soy. If they are a staple in your diet, you should definitely soak them before eating. And even if you do that, I recommend consuming not more than a handful of them a day to be on the safe side.
Combining different sources is the key
The most practical approach is eating a combination of different protein sources. For example, rice and pea proteins are complementing each other so well that together they almost have a perfect amino acid profile. Find good protein sources like legumes, quinoa, leafy greens, seaweeds, nuts and seeds, and combine them during a day of eating. Having a good variety will make it easier to cover your amino acid requirements and limit the anti-nutrient and toxin content.