Poultry further processing (Chicken nuggets & Strips) - Quality related issues and sensory

Good day team

I am faced with a problem on further processing of chicken where the chicken strips are having darker brown(burnt) spot on the coating when deep fried and it doesn't look desirable visual.

Process:

Mixing Meat block, Forming, 1st Dusting, butter dip, 2nd Dusting, Butter dip, breadcrumbs coating, Fry (30 Sec/180oC), Oven (35min/80oC), Freezing to -15oC. deep fry for 3 mins. then experience the browning spot.

Anyone and those on the further processing of chicken please help 

That sounds like oxidation, is the breading heavier where the brown spots are?

What's the oil cleaning process/frequency

Is it possible the strips are picking up old batter/crumb from the fryer

Are you blast freezing?  or is this a regular walk in freezer

Thank you for your input, Scampi,

That sounds like oxidation, is the breading heavier where the brown spots are? No, the breading is evenly distributed on the strips

What's the oil cleaning process/frequency - the Oil is being cleaned daily and we did a trial to see if oil quality is playing a role but even with a new oil, we still experience the brown spot

Is it possible the strips are picking up old batter/crumb from the fryer - new oil was used after cleaning the fryer but the results are still the same

Are you blast freezing?  or is this a regular walk-in freezer - It's a Spiral blast freezer.

would the quality of the breast be causing this browning on the surface of the strips? like visible blood veins and blood clot on the fillets or breast.

Theoretically, blood will do that, but given that this is a fully processed product, the likelihood of an intact vein making it to your finished good is quite low

If you believe it to be clotting, you need to investigate further up stream to see if the carcasses are being trimmed correctly

is it possible it's seasoning that isn't properly blended?

Is the oil too hot?