In commercial manufacturing of any product, time is money.
If you ran a shoe factory and it required 3 days to manufacture a pair of shoes, how would your factory perform compared to a competitor that made a similar pair of shoes in 3 hours? Obviously, the shorter the time required to manufacture a product, the greater the productivity, the more potential there is to turn a profit.
The same principle applies to fermented foods: the shorter the time period of fermentation, the greater the productivity. The primary goal of commercially fermented foods is therefore to produce as much product in as short a time period as possible. The goal is not to provide the maximum number of microbes for health benefits.
But our goal in consuming fermented foods is to maximize the number of microbes produced, regardless of the time required. In general, the greater the number of microbes, the greater the potential benefits. Note, for instance, that many of the fantastic health effects experienced with the Lactobacillus reuteri yogurt had never been observed before, even though these species/strains (the DSM 17938 and ATCC PTA 6475) have been available as a commercial probiotic called Gastrus for over a decade—but providing only 100 million CFUs (colony-forming units, the microbiologists’ way of saying live microbes) of each strain, compared to the several hundred billion that we obtain with my method of extended yogurt fermentation. (The executives I talked with from the manufacturer, BioGaia, in Stockholm, Sweden, were oddly indifferent, not recognizing that they had overlooked far more interesting effects than the reduction in colic and regurgitation they had documented in infants.)
The process of bacterial doubling to increase microbial counts does not continue ad infinitum, of course, and a plateau effect will develop, after which there is no further increase in number of live microbes and an increase in dead microbes. For L reuteri, this plateau effect develops between hours 36 and 48 of fermentation. Similar phenomena apply with fermentation of other microbial species such as Leuconostoc mesenteroides and Pediococcus pentosaceus.that are typically found in fermented sauerkraut, kimchi, and fermented meats—the longer the fermentation time (up to a point), the greater the number of microbes.
When fermenting veggies and other foods on your kitchen counter, fermentation time varies depending on your choice of vegetable (tomato, for instance, ferments rapidly, while peppers ferment more slowly), whether you used a starter culture or relied on the microbes naturally resident on the vegetable’s outer surface, and temperature. It is not uncommon to require 3 days, 7 days, or even several weeks for fermentation to fully proceed.
If you buy commercially fermented foods (that are becoming increasingly available) for convenience, recognize that it was likely fermented for a short a time as possible. Rarely, if ever, do commercial products specify the amount of time allowed for fermentation, so it’s a safe bet that it was fermented for maximum productivity, not for maximum microbial coiunts.
For these reasons, should you buy commercially fermented foods, consider keeping it on your kitchen counter for several more days to allow fermentation to proceed further to increase bacterial counts. The amount of time does not have to be precisely controlled, but can be judged by taste—the more fermented foods you consume, the more you will be able to judge by taste whether fermentation has achieved a maximum. And, of course, there are recipes to help that you can find in my Super Gut book or the many recipes from my friend, Donna Schwenk, book author and food fermentation expert. People are often shocked at this, assuming that leaving it out at room temperature will invite rot. But that is the beauty of natural fermentation: healthy microbes will “outmuscle” unwanted species such as fungi like Aspergillus and you will obtain far greater counts of healthy microbes. If you remain squeamish about all this, consider looking at the starter cultures that Donna advocates that accelerate the process.
