Ripening of Hard Cheese Produced from Milk Concentrated by Reverse Osmosis

• Published in: Foods 2019-05, Vol.8 (5), p.165
• Main Authors: Taivosalo, Anastassia, Kriščiunaite, Tiina, Stulova, Irina, Part, Natalja, Rosend, Julia, Sõrmus, Aavo, Vilu, Raivo
• Format: Article
• Language: English
• Subjects: cheese ripening; concentrated milk; hard cheese; reverse osmosis; volatile compounds
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods8050165

The application of reverse osmosis (RO) for preconcentration of milk (RO-milk) on farms can decrease the overall transportation costs of milk, increase the capacity of cheese production, and may be highly attractive from the cheese manufacturer's viewpoint. In this study, an attempt was made to produce a hard cheese from RO-milk with a concentration factor of 1.9 (RO-cheese). Proteolysis, volatile profiles, and sensory properties were evaluated throughout six months of RO-cheese ripening. Moderate primary proteolysis took place during RO-cheese ripening: about 70% of α -casein and 45% of β-casein were hydrolyzed by the end of cheese maturation. The total content of free amino acids (FAA) increased from 4.3 to 149.9 mmol kg , with Lys, Pro, Glu, Leu, and γ-aminobutyric acid dominating in ripened cheese. In total, 42 volatile compounds were identified at different stages of maturation of RO-cheese; these compounds have previously been found in traditional Gouda-type and hard-type cheeses of prolonged maturation. Fresh RO-cheese was characterized by a milky and buttery flavor, whereas sweetness, saltiness, and umami flavor increased during ripening. Current results prove the feasibility of RO-milk for the production of hard cheese with acceptable sensory characteristics and may encourage further research and implementation of RO technology in cheese manufacture.