Result of hazelnut cleaning
from impurities with color sorter

The hazelnut is the fruit of the hazel tree. They are also known as cobnuts or filberts according to species. A cob is roughly spherical to oval, about 15–25 mm long and 10–15 mm in diameter, with an outer fibrous husk surrounding a smooth shell, while a filbert is more elongated, being about twice as long as its diameter. The nut falls out of the husk when ripe, about seven to eight months after pollination. The kernel of the seed is edible and used raw or roasted, or ground into a paste. The seed has a thin, dark brown skin, which is sometimes removed before cooking.

Hazelnuts are used in baking and desserts, confectionery to make praline, and also used in combination with chocolate for chocolate truffles and products such as chocolate bars, hazelnut cocoa spread such as Nutella, and Frangelico liqueur. Hazelnut oil, pressed from hazelnuts, is strongly flavoured and used as a cooking oil. Turkey is the world's largest producer of hazelnuts.

 All grades of hazelnut to be considered as high quality kernels should posses the following features (only in terms if the right conditions of keeping kernels are followed): whole nuts; absence of a husk parts or presence of a scratch with less than 3 mm length and less than 1,5 mm depth is no a defect;

• Dry, with no odd surface moisture;
• Clean and with no visible foreign substances;
• Not defected; products with rot and taints are prohibited as the reason of rejecting from consumption;
• Wholly developed, but shriveled and shrunken kernels are prohibited;
• Not spoiled;
• With no defects which can be a reason of inapplicable for consumption;
• With no alive insects or ticks regardless their development stage;
• With no visible defects left by insects, ticks and other pests;
• With no mold;
• With no outside smell and/or taste.