Sour cream is a cultured dairy product that easily spoils if not handled properly. Knowing how to identify signs of bad versus fresh sour cream can help avoid foodborne illness. This article covers indicators of spoiled sour cream, proper storage methods, what causes it to go bad, if moldy sour cream is safe to eat, and how long sour cream lasts refrigerated and frozen. Using these guidelines can help ensure you are able to fully enjoy the delicious tang of sour cream before it expires.
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Signs of Fresh Sour Cream
Here are some signs that indicate sour cream is still fresh and safe to eat:
- Creamy texture. Fresh sour cream is smooth and creamy, with a thick, spoonable consistency.
- Tangy taste. It will have a pleasant mild to tart, tangy taste when fresh.
- White color. The sour cream is white to off-white, with no browning or yellow discoloration.
- Clean lactic smell. It has a mild dairy odor, without any rancid, cheesy or rotten smell.
- No separation. Fresh sour cream is emulsified, with no watery liquid at the surface.
- Consistent texture. There are no lumps or graininess in freshly opened sour cream.
- Tight packaging. The sour cream tub has no popped sides or curdling underneath the lid.
Once opened, sour cream that develops discoloration, separation, or a foul smell should be discarded.
What Causes Sour Cream to Go Bad?
There are several factors that lead to sour cream spoilage:
- Microbial growth. Yeasts, molds and bacteria can grow rapidly if sour cream is left at warm temperatures.
- Temperature abuse. Heat encourages rapid microbe and enzyme activity that deteriorates sour cream.
- Age and exposure to air. Oxygen allows undesirable bacteria to grow and lowers the pH over time.
- Contamination. Introducing spoilage microorganisms through dirty utensils or hands.
- Improper storage. Temperature fluctuations, repeatedly opening container, etc.
Keeping sour cream refrigerated below 40°F inhibits microbial growth and slows the rate of quality deterioration.
Signs That Your Sour Cream Is Bad
Like any dairy food, sour cream has a limited shelf life and can spoil if left for too long. There are clear signs you can look for to determine if your sour cream has gone bad.
Check sour cream for these visible signs of spoilage before eating it:
1. Off Odor
When fresh, sour cream smells mildly tangy and creamy. As it spoils, the odor becomes noticeably sharp, unpleasant and vinegar-like.
A strong, foul smell that hits you as soon as you open the container means the sour cream has turned. Discard sour cream with an “off” odor.
Key Point: There is a distinct sour, unpleasant smell when sour cream goes bad.
2. Changed Texture
Fresh sour cream has a smooth, creamy texture that is thick but still spreadable. As it spoils, the texture changes to become too thin and watery or extremely thick.
Runny sour cream with a clumpy, cottage cheese-like consistency is past its prime. The texture changes as proteins deteriorate. Discard thickened or curdled sour cream.
Key Point: Spoiled sour cream develops a thin, watery texture or thickens into clumpy curds.
3. Pinkish, Blue or Green Tint
The natural color of fresh sour cream is white to pale yellow. As it starts to spoil, the color may turn pink, blue, green or grayish.
Unnatural colors happen due to the growth of molds, yeasts and bacteria that form pigments as they multiply. Do not eat sour cream with coloring changes.
Key Point: Off-colors like pink, blue, gray or green indicate spoiled sour cream.
4. Mold Growth
Any mold growth, usually looking dry and fuzzy, on the surface or inside the container confirms the sour cream has gone bad. You may see black, white, green or blue mold.
Always discard moldy sour cream. Mold can spread through dairy products invisibly and release toxic compounds. Do not take risks by tasting or eating moldy sour cream.
Key Point: Mold growth in or on sour cream signals it is inedible and should be discarded.
5. Separation & Curdling
As it spoils, sour cream naturally separates into clumpy curds surrounded by watery whey. The curdling happens due to increasing acidity from bacterial cultures.
Excessive separation of whey and large curds indicates the sour cream is too old to use. Discard separated, curdled sour cream.
Key Point: Curdling and separation into whey and curds means sour cream has spoiled.
6. Slimy Texture
A very sticky, slimy texture or stringy globs in sour cream indicate a high bacteria level. The slime comes from microbial digestion of dairy proteins and fats.
Slimy sour cream not only looks unappetizing but can also cause foodborne illness if ingested, so it should be discarded.
Key Point: Sliminess or mucous-like strings mean sour cream is harboring high levels of spoilage bacteria.
How to Store Sour Cream?
Like many dairy foods, sour cream has a relatively short shelf life and needs proper storage to prevent spoilage.
Follow these guidelines to keep sour cream fresh longer.
Refrigerating Sour Cream
Proper refrigeration is the key to longer sour cream shelf life. Here are some guidelines:
- Keep sour cream refrigerated at all times, as leaving it out at room temperature promotes rapid bacterial growth. Refrigerate both unopened and opened containers.
- Store unopened sour cream in the refrigerator in its original packaging until the expiration or “use-by” date.
- Once opened, transfer sour cream to an airtight storage container. Make sure the lid seals tightly.
- Write the date opened on the container and use within 10-14 days.
- Place sour cream toward the back of the fridge, away from the door where temperatures fluctuate.
- Keep away from strong odors that may permeate the dairy food.
Constant cold temperatures keep sour cream fresher longer. Next we’ll look at how freezing can extend the shelf life even more.
Freezing Sour Cream
Sour cream can be frozen for prolonged storage using these tips:
- Whip 1 cup sour cream with 1-2 teaspoons of flour or cornstarch per cup of sour cream. The starch helps prevent separation when thawing.
- Portion seasoned sour cream into cubes to use for baking, or flat packs for dips and toppings. Leave 1/2 inch headspace.
- Place dollops on a parchment lined baking sheet and freeze until solid, then transfer to freezer bags.
- Exclude as much air as possible and seal bags tightly. Label with contents and date.
- Store frozen sour cream at 0°F or below. Use within 2-3 months for best texture.
- Thaw overnight in the refrigerator before using.
With this method, leftover sour cream stays fresh in the freezer for a few months. The small amount of added starch keeps it stable when thawed.
Where to Store Sour Cream in the Fridge
To maximize freshness, store sour cream:
- In original packaging until opened
- Transferred to an airtight container after opening
- Toward the back of the top shelf
- Away from refrigerator vents
- Away from ethylene gas-producing fruits like avocados and apples
- Away from strong smelling foods like onions
The top shelf in the back helps avoid temperature fluctuations that degrade sour cream faster. Proper air circulation also prevents moisture buildup.
Troubleshooting Sour Cream Storage Problems
Having issues keeping sour cream fresh? Here are some common problems and solutions:
Problem: Sour cream developing thin, watery texture
Solution: Avoid freezing without added starch, which causes whey separation. Refrigerate unused sour cream promptly after opening.
Problem: Pink, blue or yellow discoloration
Solution: This is natural mold growing on old product. Discard sour cream immediately at first sign of mold.
Problem: Bitter taste
Solution: Rancidity from age. Use refrigerated sour cream by 10-14 day limit after opening.
Problem: Clumpy texture
Solution: Thaw frozen sour cream completely in the refrigerator before use. Mix well before using.
Problem: Off odors
Solution: Avoid storing sour cream near strong-smelling foods like onions. Check for spoilage. Discard if smell is rancid.
With proper refrigeration and freezing methods, sour cream stays fresh and usable for weeks.
Should You Freeze Sour Cream Past Use-By Date?
It’s best to freeze sour cream by the “use-by” date for optimal freshness and quality. Freezing cannot reverse spoilage that has already started.
Check the sour cream prior to freezing:
- Look for any mold, odd textures or smells. Discard if present.
- Give it a taste test – off-flavors mean it has already spoiled.
- Check for whey separation or a watery consistency.
Only freeze properly stored sour cream that has been continuously refrigerated and is not outdated by more than a few days. For best results, freeze sour cream by the printed use-by date.
Is Thawed Sour Cream Safe to Eat?
Sour cream that has been properly frozen and thawed is safe to eat. However, the texture may be slightly compromised.
When thawing frozen sour cream:
- Thaw in the refrigerator overnight, not at room temperature.
- Check for any separation of whey or watery texture. Mix back together if needed.
- Give thawed sour cream a smell and taste. Discard if any rancid or off odors and flavors are present.
- Use thawed sour cream for cooking and baking, not whipping.
With proper handling, thawed frozen sour cream retains its freshness. It can be used in dips, dressing, baked goods and other applications.
Can Eating Spoiled Sour Cream Make You Sick?
Yes, consuming sour cream that has gone bad can cause foodborne illness. The main risks are bacteria, yeasts and mold toxins:
Harmful bacteria like Staphylococcus aureus, Salmonella, Listeria, Bacillus cereus, E. coli and Clostridium botulinum can grow rapidly in spoiled dairy products when temperature abused.
Ingesting high levels of these pathogens may cause vomiting, diarrhea, abdominal pain, fever, chills and other symptoms starting 1 to 7 days after eating contaminated dairy. Vulnerable groups are most at risk of severe illness.
Yeasts & Mold Toxins
Some molds and fermenting yeasts in spoiled dairy may form toxic compounds called mycotoxins. They have been linked to allergic responses or nausea when ingested in high amounts.
However, adverse health effects directly due to mycotoxins seem uncommon. Still, it’s smart to discard moldy or curdled sour cream that may contain higher toxin levels.
Key Point: Bacteria, yeasts and toxins in spoiled sour cream can potentially cause foodborne disease if consumed.
Is It Safe To Bake or Cook With Spoiled Sour Cream?
No, you should avoid using sour cream that smells or looks bad in baked goods or other foods even if they will be cooked.
Bacteria and toxins can often withstand cooking temperatures. The high microbial levels and potential mycotoxins cannot be guaranteed to be destroyed by baking.
It is not worth getting yourself or others sick over. Always discard sour cream that has gone bad and do not try to use it in recipes.
Key Point: Do not use spoiled sour cream in cooking, baking or recipes. The safety risk remains even after heating.
Frequently Asked Questions
Can you freeze an already open container of sour cream?
Open sour cream can be frozen but should be used within 1-2 months. Freeze in airtight bags or containers to prevent freezer burn.
Is it safe to eat sour cream after the expiration date?
It’s not recommended to eat sour cream past the expiry date, especially if it has been opened. Use smell and texture to check for spoilage before consuming older sour cream.
Why does my sour cream have a yellowish liquid on top?
Some separation of whey is natural in sour cream. However, excessive liquid or curdling indicates the sour cream is old and no longer fresh. Discard sour cream with significant separation.
Can spoiled sour cream make you sick if it’s cooked?
Yes, it’s still risky to eat cooked spoiled dairy, as the bacteria or molds can persist. Always err on the side of caution and discard expired or questionable sour cream.
Can you substitute plain yogurt for sour cream?
Plain yogurt can work as a sub for sour cream in some cases thanks to the tangy flavor. However, the thinner consistency may alter the texture in recipes.
Sour cream has a relatively short shelf life and it’s important to know when it has gone bad. Look for curdling, separation, gas bubbles, unusual colors or foul odors.Promptly refrigerate unopened sour cream by the sell-by date and discard opened containers after 3 weeks. Never eat moldy sour cream. Follow proper storage and food safety practices to fully enjoy its flavor before it expires. Exercising caution with sour cream helps prevent foodborne illness.