How to store unripe avocado?

In this brief guide, we are going to answer the question “How to store unripe avocado?”. We will also discuss what is the shelf life of avocados, how to know if avocado is ripe and how to tell if avocado has spoiled. 

How to store unripe avocado?

To store the unripe avocado, you have to get a brown paper bag from your local grocery. Empty the bag and place the avocado at the bottom. Fold the top of the bag over itself to partially seal the bag (1). 

Brown paper bags are important in storing unripe avocado because as the fruit ripens, a chemical called ethylene is released. The bag will trap it inside, which will encourage the fruit to ripen more quickly (2,3).

The place where you are going to store the unripe avocado should have a temperature somewhere between 65 to 75 degrees Fahrenheit so that you can make sure that the avocado will ripen evenly (3).

But if you want to slow down the ripeness you can store unripe avocados in the fridge and extend their shelf life (1).

What is the shelf life of unripe avocado?

The shelf life of unripe avocados at 4–13 °C is 14–28 days, with minimum oxygen (O₂) and carbon dioxide (CO₂). Storage at room temperature reduces shelf life to 5 to 7 days (4,5).

The time it takes for an avocado to ripen is determined by its initial stage of ripeness as well as the temperature outside. Unripe avocados can be sped up by placing them in a paper bag (2).

What affects the shelf life of unripe avocado?

Ripeness at purchase

Avocados purchased already ripe have a limited shelf life and should be used within a few days since they may spoil faster. Unripe avocados, on the other hand, may be stored for extended lengths of time until they mature (6).

Storage temperature and humidity

Temperature and humidity can have an impact on the shelf life of unripe avocados. Avocados maintained at room temperature ripen faster than those stored in the refrigerator. 

Place ripe avocados in the refrigerator to keep them fresher for longer. However, keep in mind that chilling might cause the flesh to discolor and alter texture dramatically (2).

Handling and bruising

Avocados are delicate fruits, and rough handling or excessive pressure can cause bruising, which accelerates deterioration. Avocados should be handled with care and should not be dropped or squeezed excessively (2).

Exposure to air

Avocados are susceptible to oxygen, which can result in browning and deterioration. When you cut an avocado open, the flesh is exposed to air, which causes oxidation and browning. 

To reduce this, keep chopped avocados with their pits intact, sprinkle lemon or lime juice on the exposed flesh, then securely wrap them in plastic wrap or place them in an airtight container (6).

Ethylene exposure

Ethylene is a natural plant hormone that promotes fruit ripening, especially avocados. Knowing that if you want to ripen avocados faster, put them in a paper bag alongside a ripe banana or apple, both of which produce ethylene gas. 

If you want to slow down ripening, keep avocados isolated from ethylene-releasing fruits (3,7).

How do you know if an avocado is ripe?

Testing avocados for ripeness helps you determine either they are to be used early or later or not at all (if spoiled). There are several ways to check the avocados for their ripeness, a few of which are explained below (3,6):

Examine the avocado’s color

Testing avocados by looking at their color is not the only way to examine them, but it can help you a lot. Like, ripe avocados are typically dark with hints of green. 

So, if you want to use the avocado right after getting home, choose one that is dark. If you plan to use one in a couple of days, select a greener one.

It is important to know the type of avocado that you are looking at because some varieties of avocado such as the Fuerte, Ettinger, Reed, and Sharwill stay green when they are ripe.

Examine the avocado’s skin

While checking the skin of the avocado, observe the color of it as well as its texture. The skin should be slightly pebbled, but make sure that there are no large indentations that may indicate the fruit has been bruised.

Examine the avocado’s stem

Flicking the small stem of the fruit is the preferred method for identifying the ripening status of avocado. When flicked, if it comes off easily and you can see green underneath, the avocado is ripe. 

But if it does not come off easily or you see brown underneath, the avocado is not yet ripe, or it is overripe and therefore unusable.

Squeeze the avocados

Place the avocado in the palm of your hand and gently squeeze. If the avocado gives off gentle pressure then it is ready to eat. If an avocado feels firm or hard, it isn’t ripe yet. Purchase it only if you plan to use the fruit several days in the future.

How to tell if avocado has spoiled?

Several factors must be evaluated to determine if an avocado has soured. First, visible signs of decomposition such as mold growth caused by Colletotrichum spp. or severe browning of the flesh suggest microbial infection or oxidation (8). 

Texture changes, such as severe softness, sliminess, or a gritty texture, might indicate spoiling due to enzymatic breakdown or bacterial activity. Erwinia and Klebsiella aerogenes are bacteria species that were already found in spoiled avocados (9). 

Unpleasant scents such as sour or fermented smells may also indicate bacterial or fungal development on avocados (8,9). 

Finally, because of the breakdown of lipids, rotten avocados can have an unpleasant or rancid flavor. Combining visual, textural, olfactory, and gustatory evaluations can assist in establishing if an avocado has been rotten (10).

Conclusion

In this brief guide, we answered the question “How to store unripe avocado?” We also discussed  what is the shelf life of avocados, how to know if avocado is ripe and how to tell if avocado has spoiled. 

References 

1. Hebishy, E., Tas, A.A. 4-hexylresorcinol and sodium metabisulphite-based edible coatings for avocado shelf-life extension. Applied Food Research, 2023, 3, 1.

2. Kassim, A., Workneh, T.S. Influence of postharvest treatments and storage conditions on the quality of Hass avocados. Heliyon, 2020, 6(6).

3. Eaks, I.L. Ripening, Respiration, and Ethylene Production of ‘Hass’ Avocado Fruits at 20° to 40°C. J. Amer. Soc. Hort. Sci., 1978, 103(5):576-578.

4. Nor, Shahidah Md, and Phebe Ding. Trends and advances in edible biopolymer coating for tropical fruit: A review. Food Research International, 2020, 134.

5. Blakey, R. J. et al.The importance of maintaining the cold chain to avocado ripening and quality. South African Avocado Growers’ Association Yearbook, 2009, 32, 2.

6. The Commercial Storage of Fruits, Vegetables, and Florist and Nursery Stocks. Agriculture Handbook Number 66, 2016, 216-222.

7. Pech, J.C. Current challenges in postharvest biology of fruit ripening. Current Agricultural Science and Technology, 2013, 19, 1-18.

8. Akpoka, A.O. Biochemical characterization of bacteria and fungi isolates associated with post-harvest spoilage of avocado pear (Persea americana) sold in two fruit markets in the benin city metropolis, nigeria. Bacterial Empire, 2020,3, 1-4.

9. Hassan, M.K., Dann, E.K. Effects of Treatment with Electrolyzed Oxidizing Water on Postharvest Diseases of Avocado. Agriculture, 2019, 9(11):241.

10. Araújo, R.G. AguilarAvocado by-products: Nutritional and functional properties. Trends in Food Science and Technology, 2018, 80, pp. 51-60,