The value of life...and food!

Unfortunately, two of our chicks turned out to be roosters.  So we were faced with the difficult decision of what to do with them.  I explored KSL classifieds and was surprised to see the number of people offering roosters to a new home with as expected, very few takers.  After many days of deliberation Trent and I decided we would eat them.  I oven fried the chicken meat and that night at dinner my husband had an amazing experience that touched both of our hearts.  His dinner prayer was more meaningful than usual.  He actually felt tremendous gratitude toward our chicken for giving up his life so we can live.   
Now comes the million dollar question.  How do I, as a mother, nurture my family's feelings of gratitude for their food when it is faceless and comes from the grocery store? Over the years, I have tried FHE lessons and prayer thanking the Lord for the animals and vegetables that provide us with food at the personal expense of giving up their life and I just get eyes rolling and sniggering.  Any suggestions?