It is a peculiar fact that frozen green peas, those humble rock-hard orbs, are almost always better than fresh. Unless you have the joy of a garden and the ability to eat peas right off the vine, fresh peas take so long to reach grocery store displays that enzymes break down their sugars into starch, turning them mealy. Frozen peas, which are frozen within hours of being picked, keep their sweetness and crispness, not mention their bright colour.
There was a time not so very long ago, however, when what came out of your freezer was – well, not to put too fine a point on it – bad. While people in chilly climes have been preserving food by freezing for longer than we probably can record, in the early 20th Century, processed food companies had a lot to learn when it came to making defrosted cod, peas and other foodstuffs palatable. Frozen food was especially dogged by a depressingly mushy texture. It was a great unifier across products: mediocrity for all.
The idea of rendering food edible for the indefinite future by freezing had been appealing for quite some time. Sir Francis Bacon, the famed statesman who is behind what we now call the scientific method – in which an observation leads to a question that can be tested – died shortly after an impromptu food freezing test in 1626. He and a comrade bought a chicken from a poor woman, had her kill and gut it, and stuffed the body cavity with snow to see if it would preserve it. His untimely demise from pneumonia soon after prohibited him from continuing the experiment, but the concept had legs.
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A turning point in the frozen food industry’s history came when Clarence Birdseye, a naturalist employed by the US government, moved to Labrador – which is today part of Canada – in 1912. There, he consumed animals from lynx to gulls with gusto, taking copious notes (whale meat was much like beef, he argued). The Inuit in the area habitually froze food during the winter months. Birdseye learned what everyone else there already knew, that the very coldest months produced the food that tasted best after being defrosted.
That led to an interesting hypothesis. In a Newfoundland Quarterly article about Birdseye’s adventures, Matthew Hollett writes: "Comparing a fish frozen in midwinter to one frozen in spring, Birdseye noticed that the ice crystals were much smaller on more quickly-frozen fish. 'When it snows on a mild winter day,' he later wrote, 'the flakes are large, and on a cold day they will be small. It's the same principle.' Birdseye theorised that smaller ice crystals were less damaging to food, helping to preserve flavour and freshness. He tested his theory by flash-freezing cabbages, and it worked wonderfully."
Indeed, quick freezing keeps large crystals from shredding the structure of food, helping prevent that nasty mushy texture. On his return to the US, Birdseye embarked on a series of inventions and patents to capitalise on this idea. He started out with seafood, developing a special cardboard carton and experimenting with using different refrigerants and ways of freezing.
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Of all his ideas, the technique that Birdseye is most known for, one that defined the industry for decades afterwards, turned out to be a way of swiftly freezing food by putting it in cardboard cartons and pressing them between super-cooled plates, between -6 and -45C (21 to -49F) for more than an hour. What's more, peas, he found, could be kept a sprightly green colour if they were blanched before being frozen this way.
Still, his first company went out of business, and another one struggled and was eventually bought in 1929 by Postum Foods, known for their portfolio of breakfast cereals (the new division was renamed Birds Eye Frosted Foods, and Birdseye continued to work for the group). People were not really sold on the frozen food concept. While Birdseye is extensively lionised in industry histories, it actually took decades for frozen food to find its feet, even with his help.
Frozen food had to be conceived of as essentially a different thing from fresh
In Laura Shapiro's fabulous history Something from the Oven: Reinventing Dinner in 1950s America, she writes that while World War Two gave frozen food manufacturers a boost, consumers remained unconvinced, in part because the quality of the products remained poor. One set of reviews she quotes make that very clear: a team of food technologists testing frozen foods bought from California grocery stores in 1947 and 1948 found "peas with 'stale' odours, mixed vegetables with 'hay-like odour and flavour', asparagus that was 'inedible because of stringiness and off flavour', and spinach 'about as tasty as a wet piece of cloth'".
It took trial and error to discover the foods that froze well (not all of them: to this day, frozen tomatoes are still uncommon) and to improve refrigeration in transportation systems, in stores, and in people's homes. It improved enough that good frozen food, when it finally came along, fulfilled the promise Birdseye saw on that first fateful trip to Labrador.
In addition, Shapiro writes, a kind of shift took place in the minds of consumers. Frozen food had to be conceived of as essentially a different thing from fresh. Canned green beans are completely different from fresh ones, and can be enjoyed on their own merits; frozen carrots are a different thing than fresh. They are best experienced without being haunted by the memory of crunchiness.
In a few cases, as with peas, the frozen product may actually embody all that is lost in an era when most of us live far from the fields, and what arrives with the label "fresh" does not fulfil the promise of the vine.
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