Noticed a fermented smell from your chili paste in the fridge? Learn what can cause this change in aroma and how to store it correctly.
1 Answer
Chili paste smells fermented after refrigeration due to the activity of microorganisms, particularly yeasts and lactic acid bacteria, which continue to break down sugars and other compounds even at refrigerated temperatures, producing volatile organic compounds that contribute to the fermented aroma. This is a natural process, but excessive fermentation can indicate spoilage.
Detailed Explanation:
Chili paste, especially homemade or traditionally prepared versions, often contains a variety of ingredients including chilies, garlic, ginger, and sometimes sweeteners like sugar or honey. These ingredients provide a food source for microorganisms. While the initial fermentation process might be intentional in some chili pastes to develop flavor, refrigeration slows down but doesn't completely stop microbial activity.Here's a breakdown of why the fermented smell develops:1. **Microbial Activity:** Yeasts and lactic acid bacteria are commonly present in chili pastes. These microorganisms consume sugars and other carbohydrates, producing byproducts like lactic acid, acetic acid (vinegar), and various esters and alcohols. These compounds contribute to the sour, tangy, and sometimes alcoholic aroma associated with fermentation.2. **Refrigeration Slows, Doesn't Stop:** Refrigeration significantly slows down the metabolic rate of these microorganisms, but it doesn't eliminate their activity entirely. Over time, even at refrigerated temperatures, they continue to ferment the ingredients in the chili paste.3. **Volatile Organic Compounds (VOCs):** The fermentation process generates a variety of VOCs, which are responsible for the characteristic fermented smell. These compounds are released into the air and detected by our sense of smell.4. **Ingredients:** The specific ingredients in the chili paste influence the type and intensity of fermentation. Chili pastes with higher sugar content or those that haven't been properly sterilized are more prone to fermentation.5. **Storage Conditions:** Improperly sealed containers can allow air and other contaminants to enter, accelerating microbial growth and fermentation.While a slight fermented smell is often normal, a strong or unpleasant odor, along with visible mold or a significant change in texture or color, indicates spoilage and the chili paste should be discarded.
Pro Tip:
To minimize fermentation and extend the shelf life of your chili paste, store it in an airtight container in the refrigerator. Adding a thin layer of oil on top can also help to create a barrier against air and reduce microbial growth.