Saturday, July 6, 2013

A History of Smoke Preservation

Foods have been preserved by smoke curing since before the dawn of recorded history. People in all cultures the world over have relied on the smoke-curing of fish and meat products for long-term storage.

It is important to make a distinction between smoking for preservation, and smoking for texture and flavour. Today the former is common in less developed countries where transportation and climate extremes may be a factor. The later is popular in developed countries where refrigeration and an integrated logistical infrastructure for the efficient transportation of perishables is in place.
In its simplest form smoking meat and fish is similar throughout the world depending on the end product desired. Preservation can be accomplished by first cutting the flesh into thin strips and then drying them slowly over a fire — or in the sun in northern climes).
Packed as dried smoked products, these can travel great distances and remain edible for long periods of time. In all these processes, drying is of paramount importance for preservation, because it is moisture in the flesh that permits bacterial activity and spoilage. Salt accelerates the removal of water and hence its widespread use as a traditional perservative. Further, the application of extracts from the smoke (phenols, etc.) retards the development of spoilage bacteria.

Smoking In Europe And Britain During The Middle Ages

various heavily smoked and salted foods were relied upon to carry people over the lean times of late winter and into spring. Fresh fish could not be transported any distance from the port of landing unless they were preserved. Two of these products were Red Herring and Salt Cod. Red Herring was made with heavily salted herring that was smoked for up to three weeks in a kiln similar to those in use today to make "bloaters" on Grand Manan, New Brunswick today.
These herring, used initially in the home markets, were widely exported (and continue to be so today) to the West Indies in the infamous "Triangle Trade" between Britain, its Northern Colonies and the West Indian plantations. While not smoked, Salt Cod supported the expansion of trade routes throughout the world, and is a prime example of how a simple product can be of supreme importance to merchants — and the extension of government policy.

The Rapid Growth Of Logistical Infrastructure

(railways and steamships) beginning in the 1840's, enabled the transportation of perishables.

For the first time in human history it was possble to move large quantities fresh fish from one place to another. This marks the beginning of sea-fishing industrialization. As a result of the widespread availability of fresh fish, the popularity of heavily salted, heavily smoked products — a mainstay for hundreds of years — began to decline. In the same period (mid 1800's), the smoked fish products we now regard as traditional came into being. These are mildly smoked and dried and contain minmum salt as condiment.
The kipper for example was invented by John Woodger at Seahouses in Northumberland about 1843 after considerable experiment. Within a few years it had become very popular and remains so today.
Where the primary reason for smoking fish had been formerly to preserve it, it was now mainly to impart a pleasant mild smoky flavour. Rapid transportation for foodstuffs meant a long shelf-life was no longer so essential.

Smoked Fish Market

The market for smoked fish underwent a major change in the mid to late nineteenth century. And yet the actual technology of smoking fish remained much the same as it had been for centuries.

It was not until 1939 that the Torry Research Station in Aberdeen, Scotland developed the Torry Kiln that a reliable tool was generally made available to the industry. This mechanical kiln can be relied upon to produce a high-quality, uniform product time after time. The use of a forced-draft greatly enhances drying and smoke application and with the use of a heat source remote to the smoke generator a much reduced smoking time is achieved. This accomplishes two things; first, the fish is exposed to moderate temperatures (prime for bacterial growth) for a shorter period and secondly, the kiln-operator can process more fish in a given time and produce it at a consistently higher quality.
Many companies now produce kilns based on this proven technology of laminar air-flow through the product. The increasing use of micro-processors has added another quality factor that insures consistency and adaptability in processing any smoked seafood product for varying demands in any marketplace (differing salt levels, moisture content requirements, etc.).
On a personal level we have been asked if the application of all this technology removes us from the actual business of producing a really top-notch food. The answer is both yes and no. Yes, we don't have to baby-sit every load of fish now-it is controlled much more closely than any human could actually do it ourselves (people need breaks, holidays, etc.). The answer is no, it doesn't remove us from the process because the computer faultlessly carries out what we have programmed into it earlier. The result is as uniform and consistent as the changing nature of fish will allow.