Among the magnesium compounds, magnesium bisglycinate, i.e. a magnesium amino acid chelate, is listed in the Regulation of the EC Commission No. 1170/2009. It is composed of glycine and elemental magnesium. The ratio between the metal ions and amino acid ions is 1 : 2. Amino acids are a new group of compounds permitted to be used as dietary supplements for people; therefore, in the available reference literature there are no results of studies that deal with assessing the possibilities of applying them to fortify milk and milk products. The objective of the paper was to determine the possibility of applying magnesium amino acid chelate (magnesium bisglycinate) to enrich yoghurt. The impact was analyzed of the following magnesium doses added to milk being processed [mg/100 g of milk]: 0 mg (control sample); 5 mg; 10 mg; 15 mg; 20 mg; 25 mg; and 30 mg, on the thermal stability of proteins during pasteurization as well as on the quality of yoghurts during refrigerated storage. Fortifying yogurts with magnesium bisglycinate did not significantly change the sensory characteristics of yoghurts; what’s more, it prevented the phenomenon of excessive souring of the yoghurts that often occurred while increasing the time of storing them. It was also proven that it was possible to increase the content of magnesium (even up to 30 mg per 100 g of product) through adding magnesium bisglycinate prior to the process of pasteurization of milk being processed. Enriching yoghurts with magnesium bisglycinate did not cause the product to become significantly darker. The enrichment with magnesium significantly changed the adhesiveness of yoghurts; however, it did not impact the hardness and cohesiveness of those beverages during a 21-day period of storing them.