Parmigiano Reggiano cheese: general and metabolic/nutritional aspects from tradition to recent evidences

Parmigiano Reggiano cheese is the oldest italian Protected Designation of Origin product, in accordance with Regulation (EU) No. 1151/2012 of the European Parliament and of the Council of 21 November 2012 on quality schemes for agricultural products and foodstuffs. It is produced in a strictly delimited territory, which includes the provinces of Parma, Reggio Emilia, Modena, Mantua to the right of the River Po and Bologna to the left of the River Reno; also the milk must come exclusively from this strictly delimited territory. It is a hard-textured, semi-fat cheese cooked and matured slowly. Additives are not allowed. The cheese must be matured for a minimum of 12 months, with significant variations between the fresh product and the aged one, especially in terms of protein digestibility. Cheese proteins essentially consist of casein, with traces of lactoglobulin and lactalbumin: the protein intake is approx. 33.0%, and the biological value of this nutritious substance is high. Parmigiano Reggiano is a semi-fat cheese with a fat content (29.7%), lower than the protein content. Conjugated isomers of linoleic acid are found in Parmigiano Reggiano cheese in quantities of approx. 3 mg/g of lipids. The amount of vitamins present in Parmigiano Reggiano cheese, while varying in relation to aging, is sufficient to cover a high percentage of the daily vitamin requirement in children and adults. A 100 g serving of Parmigiano Reggiano cheese covers also the entire daily requirement of calcium and phosphorus for an adult person with an extremely favourable calcium/phosphorus ratio. Lactose content ranges from below limit of detection to 0.39 mg/100 gr of cheese, thus allowing to classify Parmigiano Reggiano cheese among the "lactose-free" cheeses, according to the European Commission for the formulation of infant milk criteria. The absence of lactose means that it can be administered to patients with lactase deficiency. The energy value is, in any case, high (402 kcal per 100 g), so Parmigiano Reggiano cheese has not to be considered as a supplement to a normal meal, but a food in its own right. Thanks to its composition and its richness in protein substrates, in calcium, in trace nutrients and bioactive peptides, together with its excellent lipid profile, Parmigiano Reggiano cheese can be considered a "naturally" functional food, ideal for use in every age of life and in several disorders such as diabetes, ostheoporosis and dyslipidaemias.