Protein in Pistachios
A new narrative review has been published in Nutrients Journal Special Issue "Plant-Based Diets: Benefits and Concerns". The article focused on movements towards plant-based diets and explains how there is often confusion when it comes to nuts and views around their protein quality.
The article compared the amino acid profiles of different protein food sources, including nuts. There are nine main essential amino acids – histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Within these isoleucine, leucine and valine are branched chain amino acids which have gained interest due to their ability to induce protein synthesis. It was found that pistachio nuts provide all nine essential amino acids in adequate amounts. This makes them a complete protein.
Pistachios were found to provide a higher level of branched chain amino acids compared with other nuts and foods such as brown rice and lentils. Raw and roasted pistachios had a Protein Digestibility-Corrected Amino Acid Score of 73 and 81%, higher than that of many other tree nuts. The Protein Digestibility-Corrected Amino Acid Score of roasted pistachios was only slightly lower than that of beef, chicken, and egg powder.
Pistachios align with European Union/United Kingdom nutrition claims qualifying them as being ‘high in’ fibre, monounsaturated fatty acids, copper, chromium, vitamin B6, thiamine, manganese, phosphorus, and potassium and ‘a source’ of protein, vitamin E, K, folic acid, riboflavin, magnesium, iron, zinc, and selenium. They also provide γ-tocopherol, phytosterols and xanthophyll carotenoids, which are well known for their antioxidant and anti-inflammatory actions.
There have been concerns that amino acid profiles from plant-based diets could be lacking. The inclusion of a range of protein food sources can help protein needs to be met, providing that energy needs are being met. The findings from this paper demonstrated that nuts such as pistachios can provide ready-to-eat, good-quality, plant-based protein and, being nutrient dense, make a valuable nutrient contribution to daily diets.
Further information is available via:
Derbyshire E, Higgs J, Feeney MJ & Carughi A (2023) Believe It or ‘Nut’: Why It Is Time to Set the Record Straight on Nut Protein Quality: Pistachio (Pistacia vera L.) Focus. Nutrients 15(9): 2158. Available via: https://www.mdpi.com/2072-6643/15/9/2158
Disclaimer:
This work was supported by the American Pistachio Growers.