Hazelnuts

What are

Hazelnuts are indehiscent fruits (achenes with woody pericarp), partially wrapped in a green leafy shell that comes off when ripe.

The plant that produces the hazelnuts is called "nocciolo" ( nocciòlo ); it is a tree belonging to the Coryloideae family, Genus Corylus, Avellana species (the binomial nomenclature is Corylus avellana ). It is therefore no accident that hazelnuts are also known as "avellane".

There are different varieties of hazelnuts. In Italy, the most famous are certainly those of the Langhe (Tonda Gentile), but lately the Sicilian Nostrals are also distinguished. Other cultivars are the Tonda di Giffoni, the Tonda Gentile Romana, the Camponica and the Mortarella di S. Giovanni.

The core is a tree that reaches 5-7m in height, with heart-shaped leaves and a serrated profile; it grows spontaneously in the mild climate woods and often naturally forms real bush stains (similar to plantations), also called "hazel". Under the hazelnut plants it is possible to find some mushrooms, such as the red porcinello, the berbesin and (in the subsoil) the black truffle.

The soil suitable for the development of hazel groves is draining, fertile and deep. The stone coexists very well with oaks, beeches, ash trees, maples and some poplars.

The origins of hazelnuts are European and Caucasian. In Italy, the hazel partly colonizes the plains, a good surface of the hilly crests of the Apennines (up to the Sicilian nebrodis) and is not lacking near the average alpine altitudes. It is widely cultivated in Spain, France, Turkey and Italy (especially in Piedmont and Lazio).

Nutritional Properties

Hazelnuts are oily seeds, therefore particularly rich in fats; their use is heterogeneous but, among others, we can also note the production of an alternative oil to the extra virgin olive oil (see the article: hazelnut oil).

The gastronomic uses of these fruits are very numerous and it is not at all easy to mention them all. In addition to being eaten alone, hazelnuts are used for the production of sugared almonds, nougats, chocolate, ice creams and various sweets, but also of "healthy" foods such as muesli. Hazelnuts, as "dried fruit" (or better, oily seeds), are widely used in food regimes of the type: Macrobiotic, Zone Diet and Paleolithic Diet.

Due to the moderate protein content (taking into consideration that it is a vegetable food), the hazelnuts are a valid substitute for plastic foods of animal origin; obviously, neither the quantity nor the biological value are vaguely comparable to those, for example, of meat. However, the possibility of combining several plant protein sources, if well considered, ensures the coverage of essential amino acid requirements also through a vegan diet.

Hazelnuts can be used to complete the diet's lipid intake; may seem strange, but some diets require alternative lipid sources than oil to reach even 25-30% of total calories. In this case, hazelnuts are an excellent solution.

Composition for: 100g of Hazelnuts, dried

Nutritional values (per 100 g of edible portion)

Edible part				42%
water				4.5g
Protein				13.8g
	Prevailing amino acids			Glutamic Ac, Arginine, Aspartic Ac
	Limiting amino acid			Lysine
Lipids TOT				64.1g
		Saturated fatty acids		4.16g
		Monounsaturated fatty acids		38.62g
		Polyunsaturated fatty acids		5.20g
		Cholesterol		0.0mg
TOT Carbohydrates				6.1g
		Starch		1.8g
		Soluble sugars		4.1g
Ethyl alcohol				0.0g
Dietary fiber				8.1g
			Soluble fiber	- g
			Insoluble fiber	- g
Power				655.0kcal
Sodium				11.0mg
Potassium				466.0mg
Iron				3.3mg
Football				150.0mg
Phosphorus				322.0mg
Thiamine				0.51mg
Riboflavin				0.10mg
Niacin				2.80mg
Vitamin A (RAE)				30.0μg
C vitamin				4.0mg
Vitamin E				15.0mg

The breakdown of fatty acids is beneficial for lipid metabolism. To be honest, hazelnuts do not contain large quantities of essential molecules (omega 3 and omega 6); however, the intake of omega 9 (oleic acid) is more than satisfactory, to the benefit of cholesterolemia.

Also noteworthy is the concentration of dietary fiber, important for preventing constipation, but also for reducing the risk of colon cancer, feeding the intestinal bacterial flora and modulating nutrient absorption.

The nutritional importance of hazelnuts is also attributable to the high content of vitamins (vitamin E, B6, folate and thiamine) and mineral salts (copper, iron, manganese and calcium). If taken in small doses they have antioxidant, restorative, hypoglycemic and cholesterol-lowering properties (they are a good source of plant sterols).

However, given their high caloric intake, hazelnuts should be consumed in moderation (10-20 grams are more than enough), possibly away from main meals, perhaps associating them with a pulpy fruit (kiwi, banana, apple, etc.).

Hazelnuts are particularly suitable for the hypercholesterolemic diet, due to the positive effects of omega 9 and phytosterols. They are not contraindicated in case of type 2 diabetes mellitus, hypertension, hyperuricemia and hypertriglyceridemia. However, it is good to keep in mind that very often these metabolic pathologies derive primarily from a condition of obesity; therefore, being hazelnuts extremely energetic, it is always good to take them with a certain moderation.

WARNING! Hazelnuts are potentially allergenic foods, which is why they should also be excluded from the diet of the nurse and that of the infant.

Notes on Hazelnut Oil

The hazelnut oil, obtained by squeezing the seeds, is mainly intended for the cosmetic industry, where it is used for its precious antioxidant, emollient and toning properties (it is especially suitable for very dry and dehydrated skin).

In the past, hazelnut oil has risen to the headlines for the discovery of a multi-million euro turnover, based on its illicit addition to the finest extra virgin olive oil.

See also: use of hazelnuts in herbal medicine

Hazelnut production

The harvest of hazelnuts takes place in autumn, when the fruit reaches full maturity and the wrapper shrivels, detaching with ease. Followed by cleaning and drying operations, necessary for the prolonged preservation of the food. In fact, the reduction of humidity reduces the fat rancidity and prolongs its shelf life, even if any exposure to excessive temperatures could have the opposite effect.

Once purchased, the hazelnuts with the shell should be stored in cool, dry places at room temperature (around 20 ° C) for no more than a couple of months.

The production of shelled hazelnuts also includes the low-temperature roasting of the fruit, necessarily deprived of the shell. To preserve the organoleptic characteristics and avoid the degradation of the hazelnuts, the packaging takes place by means of well-sealed containers. Once opened, the hazelnuts should be stored in a cool, dry place, possibly in a closed pot and away from sunlight and heat sources. Also in this case, the deterioration is rather rapid and the product should be consumed within a very short time.

Video Recipes Based on Hazelnuts

Even if it is improper to talk about light recipes when using hazelnuts in the kitchen, avoiding the addition of butter can certainly improve the lipid profile of the food (see hazelnut cake without butter); the use of protein powders can instead make the classic hazelnut ice cream a more suitable alternative for sportsmen, while the high percentage of hazelnuts in the chocolate spread avoids the addition of hydrogenated tropical oils and fats, often abundant in the products cheaper.