近日，中国科学院理化技术研究所研究员王俊杰团队与美国加州大学伯克利分校合作，通过利用新型低温冷冻方法——“定容”冷冻（Isochoric Freezing）保存食品。该研究成果以Analysis of global energy savings in the frozen food industry made possible by transitioning from conventional isobaric freezing to isochoric freezing为题发表在Renewable and Sustainable Energy Reviews上。

低温保存是一种减少全球食品损失的有效方法，在应对食品浪费和安全方面具有重要作用。然而，目前的全球冷链运作成本高昂，根据估计，仅食品冷藏产业所消耗的电量就占全球年用电量的4%，相当于排放6.54×108吨的二氧化碳，带来直接经济成本约1200亿美元。为了满足全球人口不断增长带来的对冷藏食品的巨大需求，需要对食品冷冻冷藏方法进行创新，以降低冷冻冷藏设备带来的碳排放和经济成本。传统的食品冷冻是在“定压”（常压）条件下进行的，除了能耗较高外，当温度降到0℃以下时，食品会发生全部冻结，不可避免地会生成冰晶对组织产生破坏，降低食品品质。

“定容”冷冻保存是利用定容腔体内冰膨胀所产生的压力，降低食品的凝固点温度：定容过程中，食品始终以过冷态保存，不存在冰晶损伤，从而提高食品品质。另外，该研究通过定量比较定压冷冻、超高压冷冻和定容冷冻等不同冷冻冷藏方法的能耗，发现定容冷冻保存过程中食品本身不存在相变，可以有效降低设备运行能耗，减少碳排放。

摘要原文

Analysis of global energy savings in the frozen food industry made possible by transitioning from conventional isobaric freezing to isochoric freezing

Yuanheng Zhao, Matthew J.Powell-Palm, Junjie Wang, Cristina Bilbao-Sainz, Tara McHugh, Boris Rubinsky

Abstract

An efficient global cold food chain is critical to the sustainability of the growing world population, and it is anticipated that the global frozen food market will reach $404.8 billion by 2027. Frozen foods are typically stored under conventional industry-standard isobaric (constant-pressure) conditions at sub-freezing temperatures, however, which can degrade the textural and nutritional quality of the food and comes at high energetic and carbon costs. While efforts to reduce this energetic toll have traditionally targeted the devices used to generate refrigeration, we herein identify that significant energy savings may be attainable by altering the fundamental thermodynamics of the freezing process itself. Here we show that preserving frozen food under isochoric (constant-volume) thermodynamic conditions, as opposed to conventional isobaric conditions, may theoretically reduce annual global energy consumption by as much as 6.49 billion kWh, with accompanying carbon emission savings of 4.59 billion kg. Importantly, these savings can be achieved rapidly and inexpensively, without any costly changes to the current global refrigeration infrastructure. Furthermore, early studies demonstrate that isochoric freezing results in substantially improved food quality, extends the preservable lifetime of fresh and otherwise delicate food products, and has cross-cutting biopreservation applications in domains as diverse as medicine, biology, and pharmaceuticals.

（本文由“食品科学网”转载，文章来源于中国科学院。图片来源于Renewable and Sustainable Energy Reviews，版权归原作者所有，如有侵权，请联系我们删除。）