Published May 1, 2005. From Cook's Illustrated.
Most commercial chicken broths are dreadful, "fowl" concoctions. So what is the time-pressed home cook to do?
Rare is the cook who has the time for the slowly simmered perfection of homemade chicken stock. The rest of us head to the soup aisle of the local supermarket to make do with some permutation of commercially prepared chicken broth. But truth be told, it could take nearly as long just to choose from the confusing array of offerings: Alongside the standard metal cans of broth and the dehydrated bouillon powders sit dozens of broths sporting "aseptic" packaging (resealable paper cartons) and glass jars filled with gloppy "base" (chicken broth reduced to a concentrated paste). Add organic, low-sodium, and gourmet-shop varieties to the mix, and the number of options quickly becomes overwhelming.
To narrow the field (from 40 samples we found at the local supermarket to 18!), we zeroed in on sodium content, which ranged from 140 milligrams to 1,350 milligrams per serving. How much salt was ideal? A preliminary tasting reconfirmed our historical preference for lower-sodium broths (around 700 milligrams per serving and below) and we selected those samples. Although the high-salt varieties fared well when tasted at regular strength (simply warmed up as soup), reducing them by even one-third—for preparing, say, a pan sauce—rendered them virtually inedible.
To further reduce the contestants to an even more manageable level, we made the first tasting—plain, warmed broth—an elimination round: Tasters would simply weed out the truly bad ones. The nine best would then advance to the finals, which would include tastings of plain broth (again) and simple gravy reductions. Finally, in both plain-broth rounds, we would make the samples' sodium levels roughly equivalent by adding appropriate amounts of salt, so tasters could focus on the flavor profiles. Saltiness would be tackled in the gravy round.
As tasters pried the lids off 18 steaming samples, nothing prepared them for the wretched sensory assault to follow. Suffice it to say the qualities separating these broths were far from subtle. Some were actually startling in their rancid, sour flavors; others were tough to smell, let alone taste. What could possibly account for such a varied spectrum of dreadful tastes and aromas? To find out, a behind-the-scenes peek at chicken broth manufacturing was in order.
In the test kitchen, we use 4 pounds of chicken to produce 2 quarts of stock—a ridiculously expensive formula for broth makers planning to charge less than $2 a quart at retail. So factories use much less. That explained why several broths in the lineup were described as "bland" and "insipid." But what about the horrible rancidity, which so vexed the panel of tasters?
Rancid off-tastes are caused by one thing: oxidation of fats. Just a few hours of air exposure are enough to cause minor spoilage that, while not unsafe, is wildly unpalatable. Occasional oxidation is an inevitable part of the broth production game, and the only way for manufacturers to combat it is with vigilant quality control. The worst offenders in terms of rancidity were products made by smaller companies, which we assume have smaller quality control staffs and programs.
To compensate for using less chicken, most manufacturers opt to add flavor enhancements, especially salt, vegetables, and monosodium glutamate (MSG). A comparison of label ingredient lists proved telling: Our favorite broths were those whose list of ingredients included most or all of the components of the standard mirepoix chefs use to make sauces—that is, carrots, celery, and onions. In fact, you can almost predict how good-tasting a commercial chicken broth will be by counting the number of mirepoix elements listed. But every additional ingredient means additional cost.
Based on past tastings, we expected the most flavorful brands to include MSG, a traditional but controversial flavor enhancer. So we were puzzled to find that only two of the 18 broths in the initial tasting included "monosodium glutamate" in the list of ingredients until additional research uncovered an interesting loophole in labeling laws. The U.S. Food and Drug Administration requires manufacturers to list MSG only if it's added in its pure form. But several food additives that contain the offending glutamic acid may be included without special labeling—among them, autolyzed yeast, yeast extract, dried whey, hydrolyzed soy protein, and disodium inosinate. A second look at the labels revealed that five of the top six broths in our lineup contain one or more of these compounds.
Because no canned broths made our top nine, we wondered if the relatively new aseptic cartons were responsible for maintaining fresh flavors without off-tastes. Only two of our broths are available in both types of packaging, and a head-to-head test revealed the flavor differences to be negligible. What's more, some of our worst-performing brands are packaged only in aseptic cartons.
So what chicken broth product should you reach for when you haven't got time for homemade? We recommend choosing a mass-produced, lower-sodium brand—and check the label for evidence of mirepoix ingredients. (The best-tasting brands get help from vegetables, a glutamic compound, or both.)