Is there a way to trim an array without creating a new array? [closed]

I want to use trim() to remove the white spaces from an array but I dont want to create a new array nor do I want to use map().

I have multiple random arrays that I want to iterate through and modify the existing array.

I have arrays that look like this.

var arr = [
   {
      "title": "sally",
      "animals": {
        "type":
           [
              [" dog"],
              [" cat "]
           ]
       }
  },
  {
      "title": "bob",
      "animals": {
        "type":
           [
              [" cow "],
              [" bald eagle "]
           ]
       }
  }     
]

but I want them to look like this:

var arr = [
   {
      "title": "sally",
      "animals": {
        "type":
           [
              ["dog"],
              ["cat"]
           ]
       }
  },
  {
      "title": "bob",
      "animals": {
        "type":
           [
              ["cow"],
              ["bald eagle"]
           ]
       }
  }     
]

I am using the split() function which is causing the values to add a space.