Why Doesn't Sugar Spoil?

TL;DR

Sugar doesn't go bad because it has a very low water activity, preventing the growth of microorganisms.

Transcript

in the video today we're answering a viewer question because mark.you asks us why doesn't sugar ever seem to go bad two foods aren't left out on the counter fresh tomatoes and a bowl of sugar within a week or so one will develop black spots and the other remains pristine albeit a little clumpy depending on the humidity in the air the reason but bas... Read More

Key Insights

• 🥘 Sugar has a very low water activity (AW) and acts as a hypertonic solution, making it an effective food preservative.
• 💦 The water-absorption property of sugar causes cotton candy to collapse when exposed to humidity.
• 🍬 Cotton candy was only commercially available since 1972 when fully automated machines were invented to produce and package it.
• 🍬 30 grams of sugar is enough to make a typical serving size of cotton candy.
• 🧂 To preserve meat using salt, it is rinsed, salted, dried for a couple of weeks, and then rinsed again before cooking.
• ✋ Using a high concentration of salt or sugar can preserve meat for long periods, although the taste may be compromised.
• 🍖 A salt concentration of around 20% on the surface of meat is needed to kill off most microorganisms.

Questions & Answers

Q: Why doesn't sugar go bad?

Sugar has a very low water activity (AW) that prevents the growth of bacteria, molds, and yeasts, making it an excellent food preservative. Its low AW also makes it unable to support microbial growth.

Q: How does sugar preserve food?

Sugar acts as a hypertonic solution, drawing water out of cells, causing them to shrivel and die. This makes the food unsuitable for microbial growth. The higher the sugar concentration, the more effective the preservation.

Q: Why does cotton candy collapse in humid environments?

Cotton candy is made of pure sugar, which has a high water-absorption property. In humid environments, cotton candy absorbs moisture from the air, causing it to collapse and crystallize.

Q: Is cotton candy unhealthy?

Cotton candy is not the worst food choice compared to many other options. It contains no fat, no preservatives, and is relatively low in calories. However, it is not a health food and should be consumed in moderation.

Summary & Key Takeaways

• Sugar has a very low water activity (AW) which prevents the growth of microorganisms, making it an excellent food preservative.

• Sugar acts as a hypertonic solution, drawing water out of cells and causing them to shrivel and die.

• Cotton candy, made of pure spun sugar, collapses and crystallizes when exposed to humidity due to its high water-absorption properties.