Binds medium- and long-chain acyl-CoA esters with very high affinity. May function as an intracellular carrier of acyl-CoA esters. Confers resistance to cold and freezing. Interacts with phosphatidylcholine and derivatives, but not phosphatidic acid and lysophosphatidylcholine. May be involved in phospholipid metabolism. Interacts with PDLP8. Mostly expressed in seeds, stems, and siliques, and, to a lower extent, in leaves, flowers, and roots (at protein level) (PubMed:8660683, PubMed:18621979). Highly expressed in root and shoot phloem companion cells (PubMed:28786767). Up-regulated in constant darkness and down-regulated in the light. Induced by cold (at protein level). Enhanced sensitivity to freezing stress. Belongs to the ACBP family.