Have you ever opened a carton of milk and felt an uncharacteristic “fishy” aroma? Or did you notice that the sour cream took on a strange onion taste, even though it wasn’t even added? The culprits of these culinary disasters are incorrect proximity of food in the refrigerator. Herring, onions and dairy products are the worst trio to store together. But why?
It’s not just a matter of smells. Even the physics of the distribution of aromas are involved here. In this article, we will look at how chemical reactions, microbiological processes and even the physics of the distribution of aromas. In this article we will look at how herring fats, onion sulfur compounds and milk lactose interact with each other, accelerating food spoilage. We’ll also tell you how to properly organize the refrigerator space to avoid “taste conflicts” and prolong food freshness.
Spoiler: it's not just about taste. Some combinations may increase the risk of food poisoning due to cross-bacterial contamination. But first things first.
Chemical warfare: how herring destroys dairy products
Herring is one of the most “aggressive” foods in the refrigerator. It's all about its composition:
- 🐟 Omega-3 fatty acids - quickly oxidize in air, forming aldehydes (substances with a pungent odor).
- 🧂 Salt - in large quantities disrupts the osmotic balance in dairy products, accelerating the separation of whey.
- 🦠 Bacteria —even in salted herring there are microorganisms that can migrate to neighboring products.
When the herring lies next to milk or sour cream, its fats begin milk proteins penetrate through plastic packaging (yes, even through tightly closed!). Aldehyde molecules bind to Such a proximity is especially dangerous forforming new compounds - they are the ones that give that “fishy” taste. Moreover, this process is irreversible: even if you remove the herring, the dairy products are already spoiled.
Such a neighborhood is especially dangerous for soft cheeses (for example, feta cheese or Adyghe cheese). Their porous structure actively absorbs foreign odors, and their high moisture content accelerates chemical reactions. As a result, the cheese may become bitter or acquire a metallic taste after 12–24 hours.
Onions: why their aroma “infects” everything around
Onions are the second “saboteur” in the refrigerator. Its danger lies in sulfur compounds (thiosulfinates), which are released when onion cells are damaged (for example, when you cut it). These substances:
- 🧅 Easily penetrate polyethylene and paper.
- 🧀 React with casein (milk protein), changing its structure.
- 🦠 Stimulates the growth of bacteria Pseudomonasthat spoil milk.
Interesting fact: red onions produces less sulfur compounds than white or yellow, but even it can ruin the taste of butter or yogurt. Especially if the onions are stored in opened or in damaged packaging.
By the way, garlic acts in a similar way, but its aroma is less “intrusive” due to the different composition of essential oils. However, you shouldn’t keep it next to dairy products either.
Microbiological factor: bacteria know no boundaries
Even if herring and onions are stored in airtight containers, the risk cross contamination remains. Here's how it works:
- There are always bacteria on the surface of herring (for example, Listeria monocytogenes or Vibrio).
- When you open the refrigerator, air currents carry germs to all shelves.
- Dairy products are an ideal environment for the proliferation of these bacteria due to the high content of water and nutrients.
Research shows that in a refrigerator at a temperature of +4°C, bacteria can “travel” to a distance from the source of infection. And if the herring was lying in 30 cm from the source of infection. And if the herring was lying in thawed form, the radius increases to 50 cm!
Particularly vulnerable:
- 🥛 Milk - due to the liquid consistency, bacteria quickly spread throughout the entire volume.
- 🧀 Cottage cheese - its acidic environment neutralizes some microbes, but not all.
- 🧈 Butter - fats absorb bacteria like a sponge.
What to do if the dairy product has already absorbed a foreign odor?
If milk or kefir smells like fish/onions, but the expiration date has not expired, you can try using them in baking (the smell is neutralized when heated; it is better to throw away the cheese or butter - their structure has already been changed at the chemical level.
The physics of smells: why sealed packaging doesn’t save
Many people think that if herring or onions are in vacuum. packaging or zip bagthere will be no problems. This is why:
| Packaging type | Protects from odors? | Reason |
|---|---|---|
| Plastic bag | ❌ No | Molecules of aldehydes and sulfur compounds penetrate through micropores. |
| Vacuum packaging | ⚠️ Partially | Odors do not come out, but when when the refrigerator is opened, they spread through the air. |
| Glass container | ✅ Yes | Glass is impenetrable to gases, but only if the lid is tightly closed. |
| Foil | ✅ Yes | Aluminum blocks volatile compounds, but is inconvenient for long-term storage. |
The key problem is air circulation in the refrigeratorWhen the door opens, warm air rises and cold air falls down, creating convection currents. They carry the molecules of smells across all the shelves. Therefore, even if the herring is on the bottom shelf and the milk is on the top, the aromas will still “meet.”
Another one. nuance: plastic containers (especially cheap ones) absorb odors over time and become their source themselves. It is better not to use such containers for storing dairy products.
Temperature regime: why +4°C does not save
Many people believe that at the right temperature (+2...+4°C) products do not spoil. This is not entirely true. Cold only slows down processes, but does not stop them completely. storage of herring/onions and milk:
- 🌡️ Fat oxidation in herring continues, albeit more slowly, Aldehydes accumulate and gradually penetrate into dairy products.
- 🧊 Salt crystals from herring can condense on the walls of the refrigerator and then fall on neighboring products.
- 🦠 Psychrophilic bacteria (those that love cold) actively multiply in milk if microbes with herring.
Moreover, temperature difference on different shelves aggravates the problem. For example:
- On upper shelves (where milk is usually stored) the temperature can be 1–2°C higher than on the lower ones. This accelerates spoilage.
- In door (where oil is often kept) the temperature fluctuates with each opening, which helps absorb odors.
Ideal solution — separate storage by refrigerator zones. But more on this in the next section.
Smell the product - a fishy or onion smell even after washing the packaging indicates spoilage.
Try a small amount - a bitter or metallic taste means oxidation of fats.
Pay attention to the consistency - if the milk has curdled and the sour cream has become watery, this is a sign of bacterial infection.
Check the expiration date - if it has not expired, but the product has changed, the neighborhood is to blame.-->
How to properly organize the refrigerator space
To avoid “taste conflicts”, follow these rules:
- Zoning the shelves:
- 🥛 Dairy products —top or middle shelf (in glass containers).
- 🐟 Fish and seafood —bottom shelf (in sealed containers).
- 🧅 Onions and garlic —vegetable box (in paper bags).
- Use odor absorbers:
- 🍋 Slices of lemon or orange on the shelf.
- ☕ An open pack of soda or activated carbon.
- Keep an eye on the packaging:
- 📦 Herring and onions - only in glass or food-grade plastic with a lid.
- 🥛 Milk - in its original packaging, but after opening, pour it into a jar.
If your refrigerator has freshness zone (with a temperature of 0...+1°C), store dairy products there. And it is better to keep herring and onions in a separate container on the bottom shelf or in a fish box (if the model has one).
Do not forget about hygiene:
- Once a month, wash the refrigerator with a soda solution (1 tbsp per 1 liter of water).
- Wipe the shelves with vinegar (it neutralizes odors).
- Check the door seals - if they are worn out, odors spread faster.
What to do if the rules have already been broken
If dairy products have already absorbed foreign odors or changed taste, follow the algorithm:
⚠️ Attention! If milk, sour cream or yogurt have uncharacteristic color (grayish, yellowish), mold or gas bubbles -they need to be thrown away. The risk of food poisoning is too high!For products without visible signs of spoilage:
- 🧀 Cheese: cut off the top layer (1-2 cm) and use the rest in hot dishes.
- 🧈 Butter: melt in a frying pan - high temperatures will kill bacteria and neutralize odors.
- 🥛 Milk/kefir: use for baking or making pancakes.
If the smell remains in the refrigerator:
- Take out all the products.
- Wash the shelves and walls with a vinegar solution (1:1 with water).
- Put on shelves odor absorbers (soda, coal, citrus zest).
- Do not turn on the refrigerator for 1-2 hours to ventilate it.
If the smell does not go away for more than a day, check drainage hole (it may be clogged with organic residues) and door seals (perhaps they are leaking air).
FAQ: Frequently asked questions about storing herring, onions and dairy products
Is it possible to store herring in a vacuum package next to milk?
Vacuum packaging protects against Odor penetration outsidebut not from Microbes getting inside opening the refrigerator. If the packaging is intact, the risk is minimal, but it is better not to take risks and keep the products on different shelves.
Why does sour cream become bitter if there were onions nearby?
Bitterness appears due oxidation of milk fats under the influence of onion sulfur compounds. These substances catalyze the breakdown of lactose, which leads to a change in taste. The process is irreversible - it is better not to consume such a product.
How long do dairy products remain fresh if stored separately from herring and onions?
If stored correctly (in glass, at +2...+4°C), the time increases by 20–30%:
- Milk - up to 7-10 days (instead of 5-7).
- Sour cream - up to 14 days (instead of 10).
- Cheese - up to 1 month (instead of 2-3 weeks).
Is it possible to freeze dairy products so that they do not absorb odors?
Freezing stops the spread of odorsbut changes the structure of the products:
- Milk after defrosting can to separate.
- Sour cream will become watery.
- The cheese will lose some of its taste.
It is better not to freeze, but to organize storage correctly.
What other products cannot be stored next to dairy products?
The “black list” also includes:
- 🍎 Apples (they release ethylene, which accelerates the souring of milk).
- 🥩 Raw meat (risk of bacterial infection).
- 🌶️ Hot spices (pepper, curry - their aromas are absorbed into the oil).
- 🍫 Chocolate (absorbs all odors).