cooling brine to which rapeseed oil has been added can cause fine ice crystals to form , resulting in the ice crystals being uniformly distributed . if the meat is immersed in brine when it is in the above described state , the freezing rate is increased and the freezing time is considerably reduced in comparison with brine to which no rapeseed oil has been added . even after putting the meat into the brine , the temperature of the liquid does not increase , staying approximately constant . when meat frozen by the method of the present invention is thawed , the thawing time can be reduced to a great extent . the reason for such a marked increase in the freezing rate is that the ice crystals caused by the addition of rapeseed oil become of supply source of freezing latent heat to the meat . as a result , a rise in temperature of the liquid is prevented , and the meat passes promptly into the zone of maximum ice crystal formation (- 0 . 5 ° c . to - 5 ° c .). thus , generation of large ice crystals as well as deterioration of the quality of the meat can be prevented . furthermore , although the process of thawing the meat is not clarified , prompt thawing can prevent the growth of ice crystals so that breakdown of the meat &# 39 ; s structure is also prevented . referring first to the drawing which illustrates a freezing device for putting the present invention into practice , in a typical manner , numeral 1 is a tank , 2 is a stirring axis , 3 is a motor for driving the stirring axis 2 , 4 is piping arranged in the tank 1 , 5 is a compressor and 6 is a basket for holding the piece of meat 7 . the tank 1 is filled with brine 8 and the basket 6 is fully immersed in the brine 8 . the brine 8 is cooled by a cooling medium which circulates through the piping 4 , while repeating compression , liquefaction and evaporation by means of the compressor 5 . the meat is frozen by immersing the basket 6 in which the meat 7 has been placed into the brine 8 for a predetermined period of time and subsequently removing the basket 6 containing the meat 7 therefrom . the brine , which is cooled from - 30 ° c . to - 42 ° c ., has a slight amount of rapeseed oil added to it , the brine includinng propylene glycol ( 40 % in weight ), calcium chloride ( 10 %) and water ( 50 %). table 1 shows the results obtained by an experiment in which the amount of the rapeseed oil added to brine is varied . the experiment was performed under the following conditions . the temperature of the brine was - 35 ° c ., beefsteaks about 20 mm thick were used as the meat piece 7 and the beafsteaks lined the basket 6 at intervals of about 10 mm . table 1______________________________________amount of rapeseed freezing thawing amount of0il added (%) time ( min ) time ( min ) drip______________________________________0 20 20 large0 . 05 15 16 slight0 . 1 10 10 nil0 . 5 10 10 nil1 . 0 12 13 slight______________________________________ as shown in table 1 , if the amount of rapeseed oil added is within 0 . 1 to 0 . 5 %, favorable results are obtained . meat which is frozen with brine to which rapeseed oil has been added in the aforestated range remains good tasting and fresh . on the other hand , an organoleptic test , performed while the meat is frozen , shows that frozen meat to which no rapeseed oil has been added has numerous ice crystals radially extending from its center on the surface thereof . this phenomenom is believed to cause drip . in contrast thereto , frozen meat to which rapeseed oil has been added has one thick ice crystal linearly extending or in a folded manner toward the surface thereof and almost all of the structure of the meat is normal . since the present invention does not use expensive liquid nitrogen , etc . but rather uses economical and inexpensive brine and rapeseed oil , the cost of producing frozen meat can be lowered . furthermore , since the brine containing rapeseed oil remarkably reduces freezing and thawing time , deterioration of the quality of the meat can be prevented . thus , the time necessary to produce frozen meat can be reduced and the present invention advantageously provides quicker production of frozen meat and improved quality .
a method of freezing meat such as beef , poultry , pork , etc . including the steps of cooling brine which includes rapeseed oil added into a solution of propylene glycol , calcium chloride and water and then immersing the meat into the cooled brine . the meat thus processed by the brine is frozen in freezing equipment .