摘要 |
Material to be frozen is subjected to a cooling process which involves the efficient removal of latent heat of freezing. This can be achieved by subjecting the material being frozen to a greater rate of heat extraction when the latent heat is being given up than when the then solid material is being subsequently cooled further. Efficient removal of latent heat is also facilitated by inducing nucleation of the frozen liquid. Nucleation can be initiated acoustically and/or chemically. The invention, which has particular application in the frozen food industry and in the cryopreservation of biological material, allows shorter freezing times and/or improved quality or viability of the frozen product. |