How to preserve squash

In this brief guide, we are going to answer the question “how to preserve squash”, and discuss the different methods used to preserve squash. We will also summarize the best way to preserve different squash varieties.

How to preserve squash

All fresh horticultural crops are metabolically active organisms, even after harvest, until they are either processed or consumed. Depending on storage conditions, various physiological processes, such as respiration, ripening, and senescence, can significantly impact the quality and shelf life of fruits and vegetables. To preserve vegetables, it is necessary to delay ripening and senescence. Cold storage is the most frequently used practice to decrease metabolic activity (1).

Squash is preserved by:

• Refrigerating
• Blanching and freezing
• Dehydrating
• Pickling 
• Making into noodles

Squash is a summer vegetable with over 20 varieties. Zucchinis, pumpkins, butternut squash, and yellow squash are some well-known squash types.

The pumpkin (Cucurbita L.) is a plant material containing antioxidants, e.g., carotenoids, tocopherols, phenolic acids, and flavonols. It is commonly grown in Europe, Asia, South America, North America, and Africa. It is estimated that the annual pumpkin production exceeds 20 million tonnes. It is a valuable dietary component because its pulp is rich in carotenoids and its seeds are a source of unsaturated fatty acids. Pumpkin flowers and leaves are less popular, but they are also edible. Pumpkin pulp can be consumed both raw and after being processed, e.g., cooked, or as compotes, jams, purees, and juices. The most common pumpkin species are: Cucurbita maxima, Cucurbita pepo, and Cucurbita moschata (2).

The preservation method depends on the type of squash. For example, raw zucchinis and yellow squash are preserved well by refrigeration while raw pumpkins are preserved at room temperature. 

Preserving squash by refrigeration

Refrigeration is a short-term preservation method for squash.

Both whole and cut squash can be stored in the refrigerator for about 1 week (3).

To refrigerate squash:

• Wash the squash.
• Dry it with a paper towel and remove the moisture. Make sure the squash is dry.
• Place the squash in a clean paper or plastic bag with an open end for ventilation.
• Place in the crisper drawer of the refrigerator.

Preserving squash by blanching and freezing

Squash, like most vegetables, must be blanched before they can be frozen. Blanching stops enzyme actions that can cause loss of flavor, color and texture (3).

Most varieties of squash can be frozen for about 1 year.

Frozen squash must be thawed before being used in dishes. Thawing frozen squash will release a lot of excess liquid which has to be discarded. 

1. Freezing squash cut into small pieces: squash pieces can be used in many dishes such as noodles, soups, etc.
2. Freezing shredded squash: Shredded squash can be used in baking. 

To freeze squash:

To freeze cut-up squash pieces:

• Wash the squash in clean water and cut them into pieces of about half an inch each.
• Blanch in water for about 3 minutes: Add no more than 1 pound of squash (4-6 cups) to the boiling water. Once the water returns to a boil, blanch squash for 3 minutes (4 minutes at elevations greater than 3,500 feet). After 3 minutes, remove the squash, using the basket or colander, and plunge pieces into cold water or ice water. The quicker the slices or grated squash cool, the more crispness they will retain (3)..
• Allow to cool down.
• Drain off all water. 
• Package into a clean container.
• Label and freeze.

To freeze shredded squash:

• Wash the squash in clean water and grate it.
• Blanch the grated squash in steam for one to two minutes. Steam blanching must be done until the squash becomes translucent.
• Package into clean containers.
• Leave about half an inch of the gap between the squash and the lid.
• Cool the jars by packing them in cold water.
• Seal the jars and freeze them.

Preserving squash by dehydrating

Drying is used to remove water from foods. As a consequence, it prevents (or inhibits) development of microorganisms, improves food preservation and reduces the weight and bulk of food for cheaper transport and storage (4).

All squash varieties can be preserved by dehydrating.

Squash can be dehydrated by:

• Using a dehydrator
• Using an oven

Blanching squash before dehydration would preserve the color and texture with no change in taste.

Dehydrated squash can be consumed on its own as a snack or it can be added to other dishes.

Dehydrated squash can also be rehydrated before adding to another dish.

To dehydrate squash in a food dehydrator:

• Clean and wash the squash.
• Slice into pieces of a quarter-inch thickness.
• Place the squash pieces on the dehydrator tray. Leave space around the pieces for airflow and consistent drying.
• Set the dehydrator to 135 F. The dehydration time is around 6 hours.
• Store the dehydrated squash in an airtight container in a cool dark place.

To dehydrate squash in an oven:

• Clean and wash the squash.
• Slice into pieces of a quarter-inch thickness.
• Place the squash pieces on a baking sheet and cover them with another baking sheet or parchment paper.
• Set the oven to the lowest temperature. The ideal temperature for dehydrating is 135 F. 
• Place the squash in the oven.
• Keep the oven door about an inch open.
• The dehydrating time in an oven is around four to six hours.
• Store the dehydrated squash in an airtight container in a cool dark place.

To rehydrate squash:

• Soak the dehydrated crisps in boiling water.
• Let the crisps absorb water for about fifteen minutes.
• Pour off the excess water and use the rehydrated squash in a dish of your choice.

Preserving squash by pickling

Zucchinis and yellow squashes are 2 popular varieties that are preserved by pickling.

Squash is preserved by pickling in a solution of salt, vinegar, sugar, and spices. There are several recipes and methods to pickle squash. 

Pickling involves preserving foodstuffs under high acid concentration, enabling their preservation for over two years without refrigeration. Squash can be preserved by unfermented pickles, which is produced by two methods: (i) “salt-stock pickle” that use a concentrated brine (up to 16% salt) where preservation is due to salt and not to fermentation, and (ii) “vinegared pickles” where raw materials are packed in vinegar (acetic acid), salt and sometimes added sugar to help develop different flavor and texture in pickles. Unfermented pickles are usually pasteurized by heating (5).

If pickling is done without canning by a water bath or a pressure canner, the pickles must be refrigerated and used within 5-6 months. If canned properly the pickled will be shelf-stable for about a year.

How to preserve squash by making noodles

Making noodles followed by freezing or dehydrating is a popular way to preserve certain squash varieties. 

Spaghetti squash is a popular choice of squash for making noodles. Zucchinis and squash are also preserved as noodles. Squash noodles can be used as salads or added to soups as a gluten-free, low-calorie alternative to regular noodles.

Best methods to preserve popular squash varieties

Here’s a summary of the best ways to preserve some common squash varieties. 

Squash variety	Preservation method
Raw	Cooked/Blanched
Zucchini	Refrigerating, Freezing, Pickling	Refrigerating, Freezing, Dehydrating
squash	Refrigerating, Freezing, Pickling	Refrigerating, Freezing, Dehydrating
Pumpkin	Store whole, uncut pumpkins at room temperature.Refrigerating cut pumpkins.	Refrigerating or freezing pumpkin cubes or puree.DehydratingCanning pumpkin cubes
Butternut squash	Refrigerating, Freezing	Refrigerating, Freezing, Dehydrating

Other FAQs about Squash that you may be interested in.

Can you eat raw squash?

Conclusion

In this brief guide, we answered the question “how to preserve squash” and discussed the different methods used to preserve squash. We also summarized the best way to preserve different squash varieties.

If you have any questions or comments please let us know.

References

1. Ziv, Carmit, and Elazar Fallik. Postharvest storage techniques and quality evaluation of fruits and vegetables for reducing food loss. Agronomy, 2021, 11, 1133.
2. Kulczyński, Bartosz, Anna Gramza-Michałowska, and Jolanta B. Królczyk. Optimization of extraction conditions for the antioxidant potential of different pumpkin varieties (Cucurbita maxima). Sustainab, 2020, 12, 1305.
3. Nummer, B.A. and Johnson, J. Summer Squash. 2010. Utah University
4. Seremet, Liliana, et al. Effect of different drying methods on moisture ratio and rehydration of pumpkin slices. Food chem, 2016, 195, 104-109.
5. Behera, Sudhanshu S., et al. Traditionally fermented pickles: How the microbial diversity associated with their nutritional and health benefits?. J Funct Foods, 2020, 70, 103971.