The experiment was conducted on samples of the dorsal muscle (musculus longissimus dorsi), taken from 60 carcasses of fattening pigs with average live weight of ca. 110 kg, characterized by meat of normal quality. A total of 120 samples, each weighing ca. 500 g, were collected. They were divided into two groups and frozen according to a cryogenic-ventilation method (60 samples) and a ventilation method (60 samples). After 2 weeks, 6, 12 and 18 months of storage at a temperature of 245 K (-28^oC), the samples were taken for laboratory analyses. It was confirmed that freezing of portioned pork according to the cryogenic-ventilation method allows prevention of excessive raw material loss during chilling, storing and thawing. After two weeks of cold storage, pork frozen in the cryogenic-ventilation system was characterized by higher pH, a slightly darker colour and better water-holding capacity than pork frozen in the ventilation system. During a long period of cold storage its pH decreased, the colour became lighter and the water-holding capacity decreased to a lower extent than in the samples frozen according to the ventilation method. An analysis of hydrolytic and oxidative changes in intramuscular lipids confirms that pork may be stored up to 18 months regardless of the freezing method employed.