The experimental material were samples of the lumbar muscle (m.longissimus lumborum) taken from 60 carcasses of fattening pigs with a live weight of ca. 105 kg, their quality was considered normal. 120 samples (ca. 500 g each) were collected in total. 60 samples were taken from the hot left sides, ca. one hour after slaughter. The other 60 samples were taken from right sides chilled at a temperature of 2° C for 24 hours. Then, the two groups of samples were divided into two subgroups for the purpose of freezing them in liquid nitrogen or in a traditional ventilation chamber. After the two weeks and, then, after the six months of cold storing, some meat samples were collected for laboratory analyses. It was found that changes in their technological properties depended on three factors: a time elapsed between the slaughtering action and the moment of starting with the freezing process, a freezing method applied, and the cold storing period. After two weeks of cold storing, the samples taken from hot carcasses and frozen in liquid nitrogen showed a darker colour, a higher pH value, and a better water-holding capacity if compared with the meat samples frozen using a ventilation method (for both hot and chilled carcass samples). During the six months of cold storage, the pork acidity increased, the meat colour became brighter, and the waterholding capacity of the meat decreased, thus, the differences in the meat quality were less distinct regardless of the freezing method employed.
pork, time from slaughter to freezing, freezing methods, time of cold storage, quality