Almonds (Prunus dulcis) are one of the most widespread and widely consumed nuts in the world. Nuts, in general, have been part of the human diet since the Neolithic era, while today they are considered a healthy snack or an integral part of many meals. In addition to their highly desirable texture and taste, almonds are especially popular with consumers because of their nutritional value, as they are rich in protein, monounsaturated fatty acids, minerals (such as Potassium, Magnesium, Calcium, Phosphorus, Zinc, Copper, Manganese), dietary fibers, vitamin B2, vitamin E, which is considered a natural antioxidant, phenols and phytosterols. On the contrary, they contain a small amount of carbohydrates. For this reason, almonds are a low glycemic index food and their consumption is associated with weight maintenance and reducing the incidence of chronic diseases, such as type 2 diabetes and coronary heart disease. There is also evidence that almonds have a protective effect against the occurrence of colon cancer.
Among their various nutrients, as mentioned above, almonds, compared to other nuts, are considered mainly a very good source of high-quality protein (at a rate of 16-22% by dry weight). Almond proteins contain essential amino acids, such as Leucine, Valine and Phenylalanine, in a proportion similar to that of soy protein, which is currently the most widely consumed vegetable protein in the world. Their amino profile is poor only in the sulfur amino acids, Methionine and Cysteine, and Lysine as well. In addition, almond proteins are quite digestible and unusually rich in Arginine, a “conditional” essential amino acid.
Arginine is synthesized de novo by the human body. However, in cases of insufficient bioavailability, such as stress and catabolic conditions, it is necessary to consume it through protein foods. According to research, Arginine is an important immunoregulatory factor. More specifically, it helps maintain the integrity or restoration of intestinal barrier homeostasis, the balance of either local or systemic immune responses of patients, tissue integrity, and also contributes to wound healing. In addition, metabolites from the breakdown of Arginine in the body, such as Polyamines or Nitric acid, play an important role in repairing and developing the gastrointestinal mucosa, while maintaining the intestinal barrier in inflammatory conditions of the gastrointestinal tract or in chronic cases. There is also evidence that Arginine enhances the cytotoxicity of natural cells by suppressing the proliferation and growth of cancer cells and reducing cancerous tumors. Of high importance is the fact that Arginine can also help lower cholesterol. For this reason, energy intake from proteins controls the LDL-cholesterol levels in the blood with beneficial effects on hypercholesterolemic individuals. In conclusion, almond proteins can be an important source of abundant Arginine with beneficial benefits for human health.
The benefits of plant protein Arginine to human health are enhanced by the presence of another amino acid, Glycine, which is also found in a significant percentage in almond proteins. It has been found that the synergistic action of Arginine and Glycine helps to control the insulin / glycogen ratio with a parallel reduction of insulin in the blood, reduction of the biosynthesis of cholesterol in the blood serum and, as a result, reduction of the possibility of cardiovascular disorders.
Almond proteins are, in addition, rich in Glutamine and Glutamic Acid (Glx) and Asparagine and Aspartic Acid (Asx) in a percentage that can even reach 47% of their total amino acids. Like Arginine, Glutamine is a conditionally essential amino acid and in certain pathophysiological conditions, such as stress due to inflammation or sepsis, and in cases of injury or chronic disease, its presence is required in greater quantities than human body can produce. Glutamine is the most abundant amino acid in skeletal muscle and plasma. It is an important immunoregulatory factor. It serves as a means of transporting nitrogen to the human viscera for the formation of proteins and other nitrogenous compounds, while playing a regulatory role in the proper functioning of the kidneys. More specifically, it is a basic substrate that allows the kidneys to secrete the acidic load, thus maintaining a constant blood pH and preventing phenomena acidosis. Another important property of Glutamine is the fact that it is a basic raw material for the proliferation of somatic cells. Based on all of this, patients with serious illnesses (such as people with cardiovascular and neurological problems, intestinal dysfunction, kidney disease, diabetes, severe catabolic disease or immunodeficiency syndromes) and postoperative or traumatized individuals need additional Glutamine intake through diet or supplements. For this reason, almond proteins are an important source of Glutamine for the proper functioning of the body and fast recovery.
Finally, during the digestion of almond proteins, mainly by the effect of Chymotrypsin and less by Trypsin and Peptin, bioactive peptides are produced, which have anti-inflammatory, antihypertensive, anti-microbial and antioxidant properties, and play a vital part in regulatory blood pressure.
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