We had a similar discoloration for our freshly minced beef patty… below was the reply given by Mr Roy to my question few months back in this same group…please go through it. We tried it and it worked.
Is there any method to stop or reduce the browning of raw beef patty… we dont want to add any artificial preservatives. The expected life of the product is 3 days. So we need to avoid browning for 3 days.
From what I remember in food chemistry and biochemistry raw meat color change should not be always misconstrued as spoilage. Unless it shows distinct characteristics of true spoilage which often us accompanied by foul aroma generated by microbial decomposition by pathogens.
The "browning color change " is the chemical reaction of the meat pigment metymyoglobin which upon the absence of oxygen forms deoxymetymyoglobin turning from red to brown…
So from the Chemistry standpoint.If there is enough oxygen on the meat surface it retain its reddish color .
Therefore the practical solution is to wrap the meat in air permeable plastic to ensure air flow .Some polypropylene sheets have porous properties; therefore with that in mind consult your packaging supplier for such porous material.
Now to ensure retention of color for the selected period ,if you pack the wrapped meat In porous plastic but you pile it on top of each other then some of then. stacked tightly ,the inner meat pieces with still turn brown gradually as there is not enough air circulation. So it should be moved around to ensure air flow or there is enough space in between meat pouches to promote air circulation ,like placing in a suitable racks in the cold room.