The Science Of Flavor

Here's a good question to get things going: which tastes better, a saltwater fish you catch and eat on the boat, minutes after it is caught, or one you catch and eat a couple of days later?  The answer is all about flavor, when it happens, when it peaks, and why.

First, let's get some science out of the way.  Every one understands that fish flesh is built differently than terrestrial animal flesh, and a lot of it has to due with the fact that fish don't have to fight gravity in the water.  Saltwater fish, however, load their muscles with free amine oxides and amino acids to counter balance the osmotic pressure of living in the ocean.  Without this balance, they would surely collapse in on themselves, not a pretty picture!  These free amino acids include the tasty compounds inosine monophosphate (IMP), glutamate and glycine.  IMP is a result of the breakdown of adenosine triphosphate (ATP) and is what gives many seafood items that savory dashi flavor.  Glutamate is the key flavor of umami, that savory bite that triggers our fifth sense of taste which lies somewhere between savory and heaven.  Glycine is mostly associated with sweetness and is predominately associated with delicious shellfish.


Ok, if you are still with me, we are going to jump into the meat of the question to get our answer.  These flavorful amino acids are found in much larger concentrations in fish than they are in land animals.  They are what make saltwater fish tasty and desirable, but they don't reach their peak flavor until the muscles begin to break down.  Directly after a fish is killed, its muscles are still bound together and have yet to disassemble into tasty amino acids.  The muscles will lock into place, a state called rigor mortis, and must be given time to continue to break down and develop into smaller compounds.  Fish flesh ages more rapidly than beef and it usually takes about 24 hours for fish to develop the mouthwatering qualities of IMP and glutamate.  Some fish, such as tuna, actually don't reach peak flavor until days later.  The bigger, oilier fish usually take longer.  If aging fish seems like a foreign concept, don't worry.  Most people think the closer the fish is out of the water the better it tastes, and for the most part they are generally right, but there are instances where a fish can be "too fresh" to enjoy.  Chefs, especially sushi chefs, wrestle with this dance after death at every serving, agonizing over the artful balance of flavor and time.

To give perspective, amino acids in beef break down at a much slower rate, meaning beef usually takes a couple of weeks to reach peak flavor.  Some companies age it even longer to allow more IMP to develop.  If it's all about getting the most flavor out of your catch, it makes the most sense to prepare your haul soon after it has come out of rigor mortis, but not before.  In the case of tuna, you might be better off waiting a couple of days.  Fresh and flavor usually run synonymous around the fish business, but there's a great deal of science happening under the flesh that makes that equation an incredibly difficult one to balance correctly.  I suggest we just leave this problem solving for the professional chefs, while we reap the pleasure of the outcomes.      

Outstanding In The Field

Outstanding In The Field (OITF) is a traveling feast that organizes farmers, chefs, ranchers, cheese makers, fishermen, winemakers, foragers, and the people they sustain around a communal meal in order to celebrate and better understand the group effort required to produce a quality dinning experience.  OITF has been at it for over 15 years now, visiting all 50 states and organizing more than 600 dinners, each one focusing on a particular farm and locale.

 Recently OITF visited Even Star Farm, where our friend Bret Grohsgal helped host a lucky bunch of diners who had the chance to check out his beautiful farm and then dine in the tranquil landscape.  Black Restaurant Group Chef Mallory Buford and Chef Danny Wells of Takoma Park restaurant favorite, Republic, lead the way in the pop-up kitchen producing savory meals using local ingredients like wild bluefish, War Shore Clams, and a bevy of Bret's most delectable produce.  Local producers such as Chapel Hill Farms, Pipe Dreams Fromage, Black Ankle Vineyards, One Eight Distilling, Denizens, 38 Degree Oysters, Black Rock Orchard, and Locust Grove also pitched in to make the evening under the dimming sun one to relish.  If you missed this event, you can follow up with OITF through their website to find out more information about future events.  If you want to taste more of Bret's produce, you can visit Republic restaurant in Takoma Park, MD, where Danny can take you on a virtual tour of the Chesapeake in just a few delicious plates.

Don't Give Up On Salmon

Recently, a market patron presented me with an idea he received from his doctor: that there was no nutritional value to eating farmed salmon.  Perplexed as to why a doctor would prescribe this nonsense, I was taken aback.  Being a simple fishmonger, it was difficult, nay, impossible to change this gentleman's mind at the time.  I mean, the advice came from a doctor.  Cleary a professional's opinion, one who's spent years understanding the human body and its needs, is going to outweigh the advice from a guy with fish guts on his shoes.

That being said, I thought this blog would be the appropriate forum for a few points on the benefits of eating high-quality farmed salmon, seeing as wild salmon season is shortly coming to an end in the upcoming weeks.  Wild salmon is a terrific choice but, soon, when the season ends, it will only be found frozen in our local markets.  In the case of fresh fish versus frozen, I am always going to advocate for fresh, and when the wild salmon season ends, I recommend trying our fresh farmed salmon.  Here's why.

Farmed salmon is good for you.  Farmed Atlantic Salmon traditionally has more heart healthy omega-3 fatty acids than their wild counterparts.  While farmed salmon also typically contains more saturated fat than wild salmon, that level of saturated fat is still much lower than other land-based protein choices.

Contaminants have historically been an issue with farmed salmon as a result of the salmon's feed.  You can still find these studies circulating the web, and often I have entertained arguments from customers using these outdated studies as "proof".  Look carefully though and you will realize that the majority of the contamination arguments quote studies that were conducted in 2002 or earlier.  Much in the way of feed improvement has happened in the last 13 years.  Salmon aquaculture (that is, farming) has greatly improved the feed recipes, eliminating the high levels of PCB's (Polychlorinate biphenyl, which is the organic pollutant historically associated with salmon farming) and other contaminants.  Today strict rules regulate the levels of contaminants that can be found in fish feed ingredients.  Now organic contaminants in farmed salmon are found at similar levels as those found in wild salmon, both at very low levels.

Salmon farming practices are getting better.  In the late 90's and early 2000's salmon farming came under intense fire for polluting their surrounding environments and harming the local wild populations of fish.  Efforts were made and there has been much success in fighting these issues.  Farms like Skuna Bay in British Columbia have reduced stocking densities, which has assisted with lowering the outbreak of disease, without the use of antibiotics.  Farms only stock sterile fish and pen technology has reduced the chance of escapees.  Many salmon farms practice crop rotation, moving open pens so that surrounding ocean environments can replenish and recover naturally.  It should also be noted that all reputable salmon farms such as Northern Harvest and True North have eliminated the use of dyes, hormones, and antibiotics in the farming process.  Land based salmon farming is in its infancy, but I predict by 2018 you will begin seeing fish reared on land being available to the domestic market.

Salmon, farmed and wild, is a healthy option when it comes to the question of what to eat.  The nutritional benefits of eating farmed salmon are numerous.  They contain healthy fatty acids, minerals, and vitamins that are not found at such high levels in other proteins.  I am no doctor, so I recommend you do the research and figure out what is best for you and your diet.  However, when quoting a study, it's just like purchasing the egg salad on special: it's best to check the date.