How does time function exactly work?

They need to be a KEY Value.

In time key value it needs to have

Exact year, month, day, hour,minute,seconds PM or AM..

If you run the script within 5 minutes(It saves "results already saved in 5/28/2105, 1:00AM") kind of like it gets results from database instead of
entirely re-running it or getting data from database
So you're thinking of efficiency here.
So format should be like

5/28/2015, 1:00PM
[
  {
    Name : "Chicken"
    Price : "$50.00"
    IMAGE_URL : "imgeurl"
    Ingridients : "ingridents"
    Description : "descrption"
  }
{
    Name : "Beef"
    Price : "$50.00"
    IMAGE_URL : "imgeurl"
    Ingridients : "ingridents"
    Description : "descrption"
  }
]
5/28/2015, 2:00PM
[
  {
    Name : "Chicken"
    Price : "$50.00"
    IMAGE_URL : "imgeurl"
    Ingridients : "ingridents"
    Description : "descrption"
  }
{
    Name : "Beef"
    Price : "$50.00"
    IMAGE_URL : "imgeurl"
    Ingridients : "ingridents"
    Description : "descrption"
  }
]

The format should be something like that :)
Also the more information you can get from that API link the better.