The list of global fermented dairy drinks runs to dozens of entries from at least as many countries, taxing the pronunciation skills of even the most multilingual among us. Danish kærnemælk and Polish zsiadle mleko sidle up against Rwanda’s ikivuguto and Iran’s doogh. Meanwhile, Scottish blaand leaves one wondering whether its name reflects its Viking origins or stands as a commentary on the fermented whey beverage’s flavor.
That so many cultures across so many generations could embrace so many variations on “spoiled" milk—and that they continue to do so long after refrigeration and GMPs brought spoilage under control—testifies not only to the universality of these beverages, but to the palate’s ability to adapt to what nature (and lactic-acid bacteria) throw its way.
And though today’s fermented dairy drinks are a far cry from their ancestors in everything from flavor profile to processing, product developers still build upon time-tested traditions in their formulations. Get the details right and these 21st-century cultured beverages will stand the test of time, too.
Come a long whey
To grasp just how diverse the world of cultured dairy drinks is, consider the difference between, say, a Danimals Rockin’ Raspberry smoothie and Central Asia’s beloved kumis: The former is sweet, fruity and designed to pacify Junior’s taste buds; the latter is alcoholic, fizzy and made from mare’s milk. What more need we say?
To be sure, notes Mukul Juneja, product manager, Givaudan, Cincinnati, “Outside the United States, most traditional drinks are not as sweet" as the yogurt beverages common in our own supermarkets. But even this distinction may evaporate as more cultured dairy products drift toward a generalized Western-style sweetness.
A case in point is Indian lassi, which Juneja says is traditionally tart like yogurt and “prepared simply with salt, pepper and maybe some cumin." But, he continues, “The more modern versions have more sugar added. And now the most popular versions are fruitier."
Cultured dairy drinks have evolved in other ways, too. On the plus side, they’re more consistent. “One of the necessities of mass production for recognizable commercial brands, as opposed to traditional homemade or cottage industry, is consistency," Juneja says. “That is probably one of the most significant areas of improvement."
We can trace a good chunk of that improvement to the widespread use of specially selected and cultured fermentative strains that replace the “starters" small-scale producers would harvest from one day’s production for use in the next. “Now we have companies dedicated to developing proprietary strains of microbial cultures designed to be stable in modern manufacturing facilities," Juneja says.
They’re also fine-tuned to enhance in the drinkable-dairy medium. According to Jonathan Hopkinson, Ph.D., senior applications scientist, DuPont Nutrition & Health, New Century, KS: “Generally, lower-viscosity cultures are used. They make acid and flavor, but produce fewer exopolysaccharides," which are the large polymers that can overwhelm the texture of a drinkable product. With fewer exopolysaccharides, you get a decrease in viscosity, and your drinkable yogurt stays drinkable.
Standard time
As for which cultures we’re actually allowed to use in yogurt drinks, the Code of Federal Regulations (CFR), surprisingly enough, has nothing to say. In fact, the CFR doesn’t specify standards of identity for yogurt drinks, at all—let alone for “smoothies." But don’t go taking that as a signal to label liberally, as the yogurt portion of any “yogurt drink" labeled as such must fit the federal definition of yogurt.
That means it must contain the lactic acid-producing bacteria Lactobacillus bulgaricus and Streptococcus thermophilus, and a minimum of 3.25% milkfat, 8.25% milk solids not fat and 0.9% titratable acidity (expressed as lactic acid) prior to the addition of bulky flavors. These standards, laid out in greater detail in 21 CFR 131.200, also apply to yogurt-and-juice-based smoothies, while milk-and-juice blends are permitted to contain any directly acidified milk product.
This still leaves manufacturers substantial room to differentiate their products. As Kimberlee (K.J.) Burrington, dairy ingredient applications coordinator, Wisconsin Center for Dairy Research (WCDR), University of Wisconsin-Madison, says, “You can find levels of fat ranging from nonfat to full fat, but protein levels don’t vary a lot." Sugar levels are lower in “light" beverages, she continues, but higher in meal-replacement types; as for total solids content in drinkable yogurt, it’s lower than in spoonable.
