Ahead of Neville Hord's appearance at Leeds Crown Court on Thursday, his family passed a statement to the media via his lawyers in which they said they were still trying to understand the attack.
Customers pinned down a suspect after 30-year-old mother Jodie Willsher was attacked at an Aldi in Skipton a week ago.
The statement read: "Neville's family wish to express our sincere condolences to Jodie's family at what should have been a time of joy and happiness for them.
"No words can convey our sorrow for this tragic turn of events.
"We are trying to understand what led Neville to this action but cannot condone what he has done. It has affected both families very deeply."
Hord, 44, was taken from custody to Leeds Crown Court where he was further remanded by the Recorder of Leeds, Judge Peter Collier QC.
In a hearing lasting just short of 10 minutes, Hord spoke only to confirm his full name, date of birth and British nationality.
The defendant, wearing grey jogging bottoms and grey sweatshirt, was flanked in the dock by two prison officers.
Family members of the defendant sat in the public gallery as the case was adjourned until January 26 when Hord, of no fixed address, will attend Bradford Crown Court for a plea and trial preparation hearing.
Mrs Willsher suffered multiple serious injuries and died at the Keighley Road store, where she worked, at about 3.30pm on December 21.
Her husband, Malcolm, described her as "lovely and warm", adding: "She was amazing, beautiful and a lovely person. She was a doting mother and a loving wife."