Research On Methods Of Accelerating Maturation Of Feta Cheese

In order to shorten the ripening time of Feta cheese, single factor and orthogonaltest were applied to study the following accelerated ripening methods: bovine milk and goatmilk proportion, ultrahigh pressure treatment and adding neutral protease. During aging ofFeta cheese, physicochemical properties such as moisture, pH value, fat (or Fat in Dry Matter),protein (or Protein in Dry Matter),12%trichoroacetic acid-soluble nitrogen, pH4.6water-soluble nitrogen and free fatty acid and rheological properties such as hardness andspringiness as well as sensory evaluation and the yield of Feta cheese were monitored tomeasure the ripening, the following results were obtained.(1)During the ripening of Feta cheese, pH value firstly decreased and then increased,the content of protein(or Protein in Dry Matter) and fat(or Fat in Dry Matter) decreased,12%richoroacetic acid-soluble nitrogen and pH4.6water-soluble nitrogen increased, thecontent of free fatty acid firstly increased then decreased, and both hardness and springinessshowed down trends.(2)Ultrahigh pressure treatment could shorten the ripening time of Feta significantly;the treatment at200MPa for15min had the best ripening effect.(3)Adding neutral protease to the curd of Feta cheese could accelerate the ripening.The best dosage of neutral protease encapsulated with chitosan and sodium alginate was300U/kg, but this kind of microcapsule was too big and couldn't distribute evenly throughout thecurd. So the method of microcapsule made should be improved.(4) the best optimum technological parameters of orthogonal test with the factors ofbovine milk and goat milk proportion, ultrahigh pressure treatment and adding neutralprotease was: bovine milk and goat milk was mixed with equal volume, yoghourt starterculture, neutral protease, vanilline should be added with1.5%,400U/kg and500mg/kgrespectively.