What is well preserved retains its value

'What’s in the barrel won’t turn sour,' an acquaintance said to me recently. He wanted to reassure me that he would still keep his promise, despite the delay. I repeated the saying to myself and realized what utter nonsense it was from a food technology perspective.

People used to believe that food would keep well if you tucked it away in a wooden barrel or tub. In the days before refrigerators, salted herring contained so much salt that it had to be soaked in milk first to make it even remotely edible. Ugh. Fresh meat was also sometimes packed into a wooden tub or barrel with plenty of table salt. That’s where the Dutch saying 'see what kind of meat you have in the tub' comes from—a way of saying you need to find out what someone is really like. Scary things could happen in a dark, dirty barrel like that, believe me. People had no idea what caused food to spoil. Fortunately, they also hit upon kimchi, tofu, and pickles: foods preserved in barrels through processes in which Lactobacillae convert sugars into lactic acid, often with the help of salt.

To my mind, the most underrated—and valuable—smart food is sauerkraut. It is high in fiber and vitamin C, and supports the microbiome and the breakdown of fat.

Sauerkraut is easy to make at home. Remove the core from a white cabbage, slice it finely to a thickness of 0.8 mm, and add 1% salt. Put everything in a bucket and place a fermentation weight on top; this pushes the shredded cabbage down so it stays fully submerged in the sauerkraut juice. That keeps the cabbage from coming into contact with oxygen and going moldy (and becoming worthless after all).

The bubbling fermentation starts right away! Lactic acid bacteria convert the sugars in the cabbage into lactic acid until its concentration reaches around 2%. Most of the work is done by the highly resilient Lactiplantibacillus plantarum, at a comfortable temperature between 10 and 20 degrees Celsius. After about 3 weeks, the product has stabilized, and the sauerkraut can be stored for well over 6 months without refrigeration.

My point is: what’s in the barrel does turn sour! But I’m not quite sure what that means for the value of my acquaintance’s promise.

IJsbrand Velzeboer
Troubleshooting food technologist