it used to be restaurants would get fish with head or gills removed and the gut removed and they stored ok

what we call a beaver knife commercial fisherman call a fish knife , the round end knife, they slice up the belly and turn the knife 90 degrees and push the gut out .

when my son worked at the restaurant they got everything in individual fillets in plastic pouches , he was probably the only person at that restaurant who knew how to fillet from whole.
and they were well know for their Friday night fish fry

my cousin has a Filet machine , it is very cool , they scale the fish , head and gut them same as always , then they lay them on the line and the machine slices with the big deli type cutting wheels and takes the fillets off the spine , then they take a small knife and remove the y-bone they do mostly whitefish
he then has a chamber vac sealer and you get fillets in whatever package size you request.

given the specialized machines efficiency and most restaurants want fillets and have cooks not chefs it saves a lot of time at the kitchen end to have everything frozen in 2 fillet packets , then you hire a kid who keeps running to the freezer all night and bringing up boxes of fish and thawing them in one of the big sinks in the plastic , when they are thawed he slices the packaging and starts laying them out on a rack to drain , then into the beer batter and fryer.

it reduces space , talent , tools , makes the product last longer in storage and easier to use fast when an order comes in trading plastic waste for food waste.

I have never tried it gut in head on , so I have no comment on that , I would do head of gut out we do that for fish we freeze to smoke later and it works well
I like chunked also , give me gutted and chunked Lakers and I will boil them. love boiled laker , whitefish is good if you have the nets but they don't take hook in the summer well.

if your fillets are a bit old and you want to freshen them up whole milk is the answer
if they have a fishy smell to them it is the enzyme all fish have and all get fishy smelling with a little time , some oxidizes faster , a soak in milk 20-30 minutes is recommended I have done it for hours with no issue to the fish did a cat fish last weekend that way , son caught it over night I think about 01:00 pulled in the drive at 03:30 and walked in the house to pass out so I get the fish out of the bait bucket live well at 09:00 warm and bright sun it is stiff partially curled ,not cold at all and slimy not smelling too good hosed off and , fillet as normal and after skinning and rinsing put those fillets in milk in a bag in the fridge , we had it that night after a rinse and pat dry on paper towel .bread and fry and you wouldn't know it hadn't looked so good when I took it out of the bait bucket.

the oxidized fish enzyme that makes fishy smell, binds to the milk possibly the fat and is washed away is how I understand it to work.

I filet my fish before I freeze it in a freezer bag with water. Keeps a year or more that way.

Numerous scientific studies have been done and Jeff is correct. Fish frozen whole, and especially if glazed repeatedly, last much longer and resist freezer burn much better than those with the skin broken or even worse with the skin removed. Those are facts.

I fish year round, so I never have many fish in the freezer.

As a matter of fact, I try not to freeze fish at all...even ice fishing. When I'm ice fishing, I put my fish on a stringer and keep them in the water, below the ice. I don't like them to freeze with the guts in them.

No question, the best fish is fish that's fresh and never frozen, but I realize not many people have that luxury.

I couldn't care less what others do or how they deal with their fish.

Same here as to not freezing. I do some but very few compared to what we eat fresh....

x2

A century or so ago, the commercial fishing industry had gotten so large and widespread that ir was forced to explore and test methods of processing and preserving catches made far distant from home ports or distribution centers. Among those who pioneered freezing as an option was a man named Clarence Birdseye and many of the techniques developed during this period were extended to vegetables and meats other than fish.

In a nutshell, the way that freezing foods works best at preserving and retaining as close to fresh quality as possible is to freeze very rapidly and cut off oxygen to the frozen product. Some methods are superior to others. For example, polyethelene is permeable to oxygen so it does not make a good container for stopping oxidation. Rapid freezing is often accomplished by creating relatively thin layers of product on metal plates that can be really cold. Much experimentation and a century of use have resulted in superior frozen products in many cases.

That's how I do it also.I will fill a Ziplock freezer bag between half and 3/4 with fillets.Then add enough water to cover the fillets,,and squeeze the air out of the bag while sealing it.Results in fillets frozen in solid ice with no air.Will last well over a year like that.

We use to take whole perch that we caught through the Ice and put them In those waxed cardboard milk containers. Fill with water and place in the freezer. A month or so later thaw and clean and eat. Never had a issue with that system.

I have eaten red snapper caught fresh and baked with the scales and guts still In the fish. Tasted just fine.

Shore lunch is as fresh as it gets.
But got to freeze some-gut is only so big.

Cant beat a shore lunch for FRESH.

One spring we went out and smoked the 3/4 to lb sunnies. Came back and didn't have time to clean them before work. Tossed them in the freezer and when we took them out 2 days later, they were mush.

My friend's dad read us the riot act because we should have been smart enough to not wreck multiple limits of huge fish.

Never did it since except for creek chubs for bait.

I vacuum pack all my fish fillets. Can't tell them from fresh up to a year later.

Common practice for commercial crab bait.

Freezer space is the reason we’ve always cleaned them. Couldn’t fit but one fish fry in the freezer if we kept them whole, lol.

Put it this way you wouldn’t put a deer or rabbit in the freezer unprocessed so why would you do that to fish other than coon bait

We have done it to small game and birds plenty of times

Never froze fish on purpose but had them freeze while fishing lots and lots of time- sometimes they thaw out and start flopping again.

Guys I think Wolfie is trolling us and those fish are bait fish.