Can out-of-date blueberries make you sick? (+5 Ways to tell)

In this article, we will answer the question “Can out-of-date blueberries make you sick?”, and how to store blueberries.

Can out-of-date blueberries make you sick?

Yes, eating out-of-date blueberries can make you sick if they are spoiled. Eating spoiled blueberries that can contain harmful microorganisms, viruses, or parasites can lead to severe illnesses. (3,4) 

If the blueberries have passed their best-by date but they don’t have any signs of spoilage, it is safe to consume them. So, it is very important to know how to detect if the blueberries are spoiled. 

What are the factors that affect the safety of blueberries?

The main factors that affect the shelf life of blueberries are temperature, humidity, and handling;

  • Storage temperature: Is the most crucial environmental factor influencing the post-harvest lifespan of fresh fruits, primarily due to its significant impact on the rates of biological reactions, including respiration (2). 
  • Humidity: The blueberries must be kept in a relatively dry environment. An environment too dry will lead to water loss, and an environment with too high humidity may lead to condensation and the enhanced growth of pathogens (2). 
  • Handling: It is important to wash the blueberries properly and manipulate them with clean hands and utensils to avoid microbial contamination due to unhygienic conditions. (1)

What are the risks of consuming expired blueberries?

Consuming spoiled blueberries can cause vomiting, diarrhea, abdominal pain, and flu-like symptoms, such as fever, headache, and body aches, which can be caused by bacteria like Salmonella, Escherichia coli, Campylobacter or Shigella. (4).

Spoiled blueberries can also lead to viral infections such as Norovirus or Hepatitis A. (3)

How long do blueberries last?

Whole blueberries last 5-10 days 1-2 weeks in the fridge if stored correctly. Whole blueberries can only last a day out of the fridge. While sliced or cut blueberries will go bad after 2 hours if left unrefrigerated. (5,7)

Frozen blueberries will last a lot more, and it can be useful for extending their shelf life, as they will last for about 8-12 months. (6)

How to tell If the blueberries have gone bad?

Here are some signs of spoilage in blueberries.


Squishy blueberries whose juice is oozing out from the damaged spots have gone bad, discard such berries immediately.

If you observe any significant browning, darkening, or dull appearance, it is a clear indication that the blueberries have spoiled. If you notice any notable alterations you should discard the berries. 

Mold growth 

White, green, or any other colored mold growing on the berries is an obvious sign of spoilage. Berries that are contaminated with molds contain mycotoxins that can cause severe food poisoning. (8)

Texture and softness

Mushy, overly soft, wrinkled, or dehydrated berries have gone bad and you should get rid of them right away. (5)

Foul smell

If the berries give off a foul or rotten smell,  you should discard them, it may be an indicator of spoilage or fermentation.

Undesirable taste

If the berries are past their expiry or best-by and there are no visual signs of spoilage but you are unsure whether you should discard or consume them, your best bet is to taste them. If the taste is off, you should discard them. 

Other FAQs about Blueberries which you may be interested in.

Are blueberries berries?

Are blue raspberries real?

How to know if blueberries are spoiled?

How to properly store blueberries?

To properly store blueberries, follow these guidelines.

Do not wash them before storing them 

Blueberries are quite perishable and moisture will accelerate spoilage. Excess moisture can lead to mold growth and spoilage. Molds will produce mycotoxins that could cause foodborne illnesses. (9)

Only rinse the blueberries just before eating or using them. 

Moreover, washing and rinsing also stip the berries off of their protective bloom, which prevents the berries from moisture loss and decay.

Check the batch properly before storage 

Remove the bitter stems of the blueberries before storage. Moreover, remove the rotten berries so that they don’t contaminate and spoil the whole lot during storage.

Always opt for plump, firm, and brightly colored blueberries. Steer clear of containers with crushed or moldy berries. Prioritize selecting fresh, healthy fruit for the best quality and taste.

Refrigerate the blueberries 

If the blueberries aren’t to be consumed within a few days of purchase, store them in the fridge. Put them in an air-tight container and store them in the fridge for 1-2 weeks. (10) 

Freeze the blueberries 

If the blueberries are overripe or you bought a large quantity freshly off the farmer’s market, freeze them for extended storage.

Freezing is a good option if you want to store your blueberries for a longer period of time or if you have a large quantity to store. Freezing them will extend its shelf life to 8-12 months. (10)


In this article, we answered the question “Can out-of-date blueberries make you sick?”, and how to store blueberries?


  1. Food and Drug Administration. Selecting and Serving Produce Safely.
  2. Kraśniewska, K., Ścibisz, I., Gniewosz, M., Mitek, M., Pobiega, K., & Cendrowski, A. (2017). Effect of Pullulan Coating on Postharvest Quality and Shelf-Life of Highbush Blueberry (Vaccinium corymbosum L.). Materials, 10(8), 965.
  3. Leblanc, D., Gagné, M., Poitras, É., & Brassard, J. (2019). Persistence of murine norovirus, bovine rotavirus, and hepatitis A virus on stainless steel surfaces, in spring water, and on blueberries. Food Microbiology, 84, 103257.
  4. Cho, K-B. Detection of Microbial Contamination in Commercial Berries. Biomed Sci letters.
  5. Miller, W.R., McDonald, R.E., Melvin, C.F., Munroe, K.A. Effect of Package Type and Storage Time-temperature on Weight Loss, Firmness, and Spoilage of Rabbiteye Blueberries. American Society for Horticultural Science. 
  6. Garden-Robinson, J. Freezing Fruits. North Dakota State University. 
  7. Andress, E.L., Harrison, J.A. Preserving Food: Freezing Fruit. University of Georgia. National Center for Home Food Preservation.
  8. Pleadin, J., Frece, J., Markov, K. Mycotoxins in food and feed. Adv Food Nutr Res.
  9. Drusch, S., Ragab, W. Mycotoxins in fruits, fruit juices, and dried fruits. J Food Prot. 
  10. United States Department of Agriculture. Food Keeper.

Was this helpful?

Thanks for your feedback!