Lightbulb Moment in Food History

Susanne Freidberg, a professor of geography at Dartmouth, has been guest blogging here about the food supply. This is her final post; we thank her very much. You can thank her too by picking up a copy of her just-released book, “Fresh: A Perishable History.”

Photo: Stephen Ausmus A White Leghorn hen.

Last week’s post talked about early-20th-century “egg gamblers” who bought eggs cheap in spring in order to sell dear in winter. Their kind of speculation proved not just controversial but also pretty risky, and ultimately doomed. Why?
Egg gamblers won only if they sold off their cold-storage stocks before fresh ones arrived in spring. They faced two major unknowns: housewives who sometimes protested egg “hoarding” with organized boycotts, and hens who might start laying earlier than expected. Because hens are acutely sensitive to shifts in daylight and temperature, all it took was a February thaw to set them off, sending egg prices plummeting.
Poultry farmers, meanwhile, just wanted to know how to get their own flocks to lay more eggs when fresh ones were scarcest and priciest. They knew that some chicken breeds laid a few more winter eggs than others, and that warm housing and a rich diet generally helped. But the most dramatic results came with the flick of a switch — literally.
Although few farmers in 1910 to 1920 had electricity, those who did discovered that hens couldn’t tell the difference between the sun and a light bulb. One early adopter in Cambridge, Mass., called it “the most definite control of production that we have.” In 1919 a Minnesota farmer wrote to Scientific American describing how his hens responded to a 50-watt bulb by “cackling and behaving in the liveliest fashion, and laying practically all their eggs in the night.” The magazine called it “a miracle.”
Some farmers worried that too much artificial light might backfire. As Hen Coop magazine reported in 1922, “A bird cannot be kept off her perch from 4 a.m. until 9 a.m. without showing the effect of the daily grind for eggs.” But by the mid-1930’s studies showed that all-night henhouse lighting paid off. If farmers could sell twice as many fresh eggs in winter, it didn’t matter that their hens wore out by spring.
As New Deal electrification projects brought power to rural areas nationwide, henhouse lighting caught on. For some poultry farmers, it took priority over electricity for the family home. By the early 1940’s, the results spelled the end of egg gambling. Thanks to “millions of modernized hens,” said Business Week, consumers no longer had to settle for storage eggs in winter.
You can probably guess what happened next. As egg production became less seasonal, agribusiness moved in. The postwar decades saw the rise of mechanized “egg cities,” each home to tens of thousands of caged layers. Enriched feeds replaced the vitamin D from sunshine, while antibiotics prevented henhouse epidemics. Unfortunately, they also fostered the spread of antibiotic-resistant salmonella.
Today’s average layer produces 250-300 eggs a year, and the niche market in fresh-laid winter eggs is long gone. The new niches range from several variations on “natural” (cage-free, organic) to the ultra high tech (traceability codes laser-etched on each shell). Among other qualities, both options cater to demand for genuine freshness — the same demand that brought us the industrial egg in the first place. Moral of the story? Be careful what you wish for.