How to know if cheese is spoiled? (5 easy ways)

In this brief article, we are going to answer the question “How to know if cheese is spoiled”, discuss the different methods of identifying spoiled cheese and the potential side effects of eating spoiled cheese.

How to know if cheese is spoiled?

There are several signs to look out for to determine if your cheese is spoiled. Here are some common signs of cheese spoilage:

Important: you must avoid eating spoiled cheese as it can cause you several health issues (1-6).

• Texture: Fresh cheese has firmness as it is semi-soft or semi-hard or hard in texture according to the type. When cheese gets spoiled it changes its texture. Spoiled cheese shows the texture of grainy or chalky texture. If you notice any slimy or sticky texture on the surface, it may be spoiled. Additionally, if the cheese appears to be harder or crumbly than usual, it may have dried out and could be past its prime.

• Smell: Different types of cheese give off different smells. In general, cheese should have a pleasant, earthy aroma, but sometimes it gives an unpleasant smell. So, you should smell the cheese while purchasing it so if the cheese starts giving different smells it means that it was spoiled. If the cheese smells sour, ammonia-like, or has a rancid odor, it may be spoiled. However, it is important to note that some cheeses, such as aged cheeses like Parmesan and cheddar, may have a slight ammonia smell that is not necessarily indicative of spoilage. However, if the smell is very strong or unpleasant, it’s best to err on the side of caution and discard your cheese.

• Appearance: If you notice any mold growth on the surface of the cheese, it may be spoiled. However, some cheeses, such as blue cheese and brie, have edible mold on the surface, so it’s important to know which cheeses are supposed to have mold and which are not.

In general, when checking for cheese spoilage, look for mold growth, inconsistent texture, and unpleasant smells. Be aware of the initial appearance, smell and texture of your cheese and track any changes to determine potential spoilage.

When in doubt, it is very recommended to discard your cheese to avoid any potential health risks.

Can you get sick from eating spoiled cheese?

Yes, eating spoiled cheese can be very dangerous and can lead to different foodborne illnesses (1-6). 

Here are some examples of different pathogens that can growth on spoiled cheese and can make you sick:

• Listeria monocytogenes: This bacterium is commonly found in soil and water, and it can grow at refrigeration temperatures (3,4,7). Symptoms of Listeria infection include fever, muscle aches, and gastrointestinal symptoms such as nausea and diarrhea. In severe cases, it can lead to meningitis or septicemia (3,4,7).

• Staphylococcus aureus: This bacterium can produce potent toxins that cause food poisoning (2,6). Symptoms of Staphylococcus aureus infection include nausea, vomiting, and stomach cramps (2,6).

• Salmonella: This bacterium is commonly found in raw meat, poultry, and eggs, but it can also be found in unpasteurized dairy products (4). Symptoms of Salmonella infection include diarrhea, fever, and abdominal cramps (4).

• Clostridium botulinum: This bacterium produces a neurotoxin that can cause botulism, a serious and potentially fatal illness (8). Symptoms of botulism include blurred or double vision, difficulty swallowing, and muscle weakness (8).

If you suspect that you have eaten spoiled cheese and are experiencing any of the above-mentioned symptoms, it is very important to seek medical attention immediately.

What should you do if you suspect you have eaten spoiled cheese?

If you have eaten spoiled cheese and you are experiencing symptoms of food poisoning, it is very important that you follow the next tips:

• Seek medical attention immediately: If you are experiencing severe symptoms such as vomiting, diarrhea, or dehydration, seek medical attention.
• Monitor your symptoms: Keep track of your symptoms and how long they last. If your symptoms persist or worsen, seek medical attention again.
• Stay hydrated: Drink plenty of fluids to replace the fluids lost due to vomiting or diarrhea. Water, clear broths, and electrolyte drinks such as sports drinks can help replenish lost fluids (9).
• Rest: Get plenty of rest to allow your body to recover. Avoid strenuous activity or exercise until you are feeling better.
• Discard the remaining cheese: If you still have the cheese that you suspect caused your illness, discard it immediately to prevent anyone else from eating it and getting sick.

Food poisoning can be serious and can lead to complications if left untreated.

So, remember: When in doubt, throw it out!

How to properly handle a cheese to avoid spoilage?

Here, you will find some tips for properly handling your cheese to avoid spoilage and prolong its shelf life:

• Purchase cheese from a reputable source: buy your cheese from a reputable cheese shop or grocery store that you trust. Make sure the cheese is fresh and has not been sitting on the shelf for too long.
• Store cheese at the proper temperature: most cheeses should be stored in the refrigerator at temperatures between 34 and 40°F. Soft cheeses, such as Brie or Camembert, should be stored in the coldest part of the refrigerator, while hard cheeses, such as Cheddar or Parmesan, can be stored in the warmer part of the refrigerator.
• Keep cheese wrapped properly: cheese should be wrapped tightly in waxed or parchment paper, or in a resealable plastic bag, to prevent it from drying out. Avoid wrapping cheese in plastic wrap, as it can trap moisture and promote mold growth.
• Use cheese within its shelf life: different types of cheese have different shelf lives (10), so it is important to use them within their recommended time frame. Here are some general guidelines for the shelf life of different types of cheese:
  • Fresh cheese (e.g., ricotta or goat cheese): 1-2 weeks
  • Soft cheese (e.g., Brie or Camembert): 1-2 weeks
  • Semi-soft cheese (e.g., Havarti or Gouda): 2-3 weeks
  • Hard cheese (e.g., Cheddar or Parmesan): 3-6 months or longer
• Store cheese properly for long-term storage: If you want to store cheese for an extended period, you can freeze it. However, some types of cheese, such as soft or fresh cheese, may not freeze well. Before freezing, wrap the cheese tightly in plastic wrap or aluminum foil and place it in an airtight container or freezer bag. Frozen cheese should be used within 3-6 months.
• By following these tips, you could be sure that your cheese stays fresh, safe and delicious for as long as possible.

References:

F1. Olsvik Ø, Wasteson Y, Lund A, Hornes E. Pathogenic Escherichia coli found in food. Int J Food Microbiol [Internet]. 1991 Jan 1 [cited 2023 May 3];12(1):103–13. Available from: https://pubmed.ncbi.nlm.nih.gov/2018703/  

2. Gajewska J, Chajęcka-Wierzchowska W, Zadernowska A. Occurrence and Characteristics of Staphylococcus aureus Strains along the Production Chain of Raw Milk Cheeses in Poland. Molecules [Internet]. 2022 Oct 1 [cited 2023 May 13];27(19). Available from: https://pubmed.ncbi.nlm.nih.gov/36235105/  

3. Melo J, Andrew PW, Faleiro ML. Listeria monocytogenes in cheese and the dairy environment remains a food safety challenge: The role of stress responses. Food Res Int. 2015 Jan 1;67:75–90. https://www.sciencedirect.com/science/article/abs/pii/S0963996914006875  

4. Colak H, Hampikyan H, Bingol EB, Ulusoy B. Prevalence of L. monocytogenes and Salmonella spp. in Tulum cheese. Food Control. 2007 May 1;18(5):576–9. https://www.sciencedirect.com/science/article/abs/pii/S0956713506000259  

5. Pourshafie MR, Saifie M, Shafiee A, Vahdani P, Aslani M, Salemian J. An Outbreak of Food-borne Botulism Associated with Contaminated Locally-made Cheese in Iran. http://dx.doi.org/101080/003655498750002385 [Internet]. 2009 [cited 2023 May 13];30(1):92–4. Available from: https://www.tandfonline.com/doi/abs/10.1080/003655498750002385  

6. Lindqvist R, Sylvén S, Vågsholm I. Quantitative microbial risk assessment exemplified by Staphylococcus aureus in unripened cheese made from raw milk. Int J Food Microbiol. 2002 Sep 15;78(1–2):155–70.  https://pubmed.ncbi.nlm.nih.gov/12222631/  

7. Kołakowska A, Madajczak G. [Listeria monocytogenes in human infections]. Przegl Epidemiol [Internet]. 2011 Jan 1 [cited 2023 May 3];65(1):57–62. Available from: https://europepmc.org/article/med/21735837  

8. Ting PT, Freiman A. The story of Clostridium botulinum: from food poisoning to Botox. Clin Med (Northfield Il) [Internet]. 2004 May 5 [cited 2023 May 3];4(3):258. Available from: https://pubmed.ncbi.nlm.nih.gov/15244362/  

9. McRobert GR. THE TREATMENT OF BACTERIAL FOOD POISONING. Br Med J [Internet]. 1934 Aug 8 [cited 2023 May 10];2(3841):304. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2445530/  

10. Jalilzadeh A, Tunçtürk Y, Hesari J. Extension Shelf Life of Cheese: A Review. Int J Dairy Sci. 2015;10(2):44–60. https://scialert.net/fulltext/?doi=ijds.2015.44.60