Incremental freeze concentration equipment with double-sandwich structure and freeze concentration method

The invention relates to incremental freeze concentration equipment with a double-sandwich structure. The incremental freeze concentration equipment comprises a crystallization and concentration unit,a cold carrier temperature control unit and a parameter control and automatic recording unit, wherein the crystallization and concentration unit comprises a crystallization and concentration tank, anouter sandwich temperature probe and multiple groups of temperature recording probes in the crystallization and concentration tank; the side wall of the crystallization and concentration tank is of the double-sandwich structure which comprises an inner sandwich layer in which a buffering heat carrier I is introduced and an outer sandwich layer in which a cold carrier II is introduced; the heat carrier I is a food-grade carrier having heat transfer and buffer characteristics; the cold carrier II is an anti-free cold carrier; the outer sandwich layer temperature probe is arranged in the outer sandwich layer; the multipl