Due to increasing interest for dairy products made from hay milk on the Slovenian market, the largest Slovenian dairy plant has decided to manufacture cheese from raw hay milk. The main goal of the master's thesis was to determine the microbiological and chemical quality of raw hay milk and its applicability as raw material for cheese production. After determining the microbiological and chemical quality of raw hay milk, same batch of milk was used for production of semi-hard type of cheese, using a commercial starter culture. Two days later, the experiment was repeated, but with a new batch of raw hay milk, and this time a semi-hard type of cheese was produced with a combination of starter and protective culture that produces nisin. The same cheesemaking protocol was accomplished every month and lasted 12 months, from June 2018 to May 2019, at the Celeia Dairy plant in Arja vas. Besides analysing raw hay milk, microbiological, chemical, and sensorial analyses of cheeses were performed as well. Microbiological quality of cheese was monitored in accordance with the guidelines for microbiological safety of raw milk cheeses with classical pour-plate microbiological techniques. As cheese-making was carried out throughout the year, the possible impact of the seasons on the microbiological quality of raw milk and cheeses was monitored as well. Results revealed that raw hay milk and both cheeses (starter culture, starter + protective culture) complied with the microbiological guidelines throughout the year. Chemical analyses of cheeses were performed according to known standardised methods. We also performed a sensory analysis of cheeses with a 20-point system. Sensorial evaluation (a short analysis test) of cheesees ranged from 18 to 12 points.
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