Butternut squash is a type of winter squash that is very popular for its sweet, nutty flavor. It’s an extremely versatile vegetable that can be roasted, puréed, added to soups and stews, and even canned for preservation. Home canning is a great way to preserve fresh butternut squash to enjoy all year round. However, like any home canning project, proper technique is critical to ensure the safety of your final product. In this article, we’ll look at tips and guidelines for safely canning butternut squash at home.
Can You Water Bath Can Butternut Squash?
Butternut squash is a low-acid vegetable, with a pH higher than 4.6. This means it cannot be safely processed using a simple hot water bath canning method. The density of winter squash combined with its low acidity creates an environment where the bacteria Clostridium botulinum could potentially survive and produce toxins. These toxins can lead to botulism, a serious and potentially fatal foodborne illness. For this reason, butternut squash must be pressure canned for safe long-term storage at room temperature.
Steps for Safely Pressure Canning Butternut Squash
Follow these guidelines for safely preserving butternut squash using a pressure canner:
1. Choose fresh, undamaged squash
Select butternut squash that is firm, heavy for its size, and free from blemishes or damaged spots. Avoid squash with punctures, cracks, or soft spots.
2. Wash and peel
Thoroughly wash squash under cool running water. Peel off the tough outer skin with a vegetable peeler or sharp knife. Remove seeds and stringy membranes.
3. Cut into 1-inch chunks
Cut peeled squash into 1-inch cubes, slices, or chunks. This size will allow for safe heat penetration during processing.
4. Steam blanch
Blanch squash pieces for 3 minutes in steam to sufficiently heat through. This helps remove air pockets and inactivate enzymes that could affect quality, color, and flavor during storage.
5. Fill jars
Ladle hot blanched squash into hot, sterilized mason jars, leaving 1 inch of headspace. Remove air bubbles and add fresh boiling water or squash broth, leaving 1 inch of headspace below the rim. Wipe rims clean.
6. Apply lids and rings
Center lids on jars and screw on bands just until fingertip tight. Do not overtighten.
7. Pressure can
Follow manufacturer’s instructions for your specific pressure canner model. Process pint or quart jars of butternut squash for 90 minutes at 11 PSI. Increase pressure to 15 PSI if you live at an altitude above 1,000 feet above sea level.
8. Cool and test seal
When processing time is complete, allow canner to depressurize naturally. Remove jars without tilting and place upright on a towel or rack. Leave undisturbed for 12-24 hours, then test seals. Sealed lids curve downward and do not move when pressed.
9. Label and store
Wipe jars clean, label with contents and date, and store in a cool, dark place for up to 1 year.
Choosing the Right Pressure Canner
A quality dial or weighted gauge pressure canner designed for home use is essential for safely canning low-acid foods like butternut squash. Do not use electric multi-cookers. Key features to look for include:
– Sturdy metal design with fitted lid forming an airtight seal during pressurization
– Rack to keep jars raised up and prevent jar-to-jar contact
– Dial or weighted gauge to accurately regulate processing pressure
– Overpressure plug for safety release if pressure exceeds 15 PSI
– Capacity to hold at least 4 quart-sized jars
Follow the manufacturer’s instructions for proper maintenance, use, and safety checks of your pressure canner before and after each use. Replace dial gauges every year and have weighted gauges tested annually to ensure continued accuracy.
Pressure Canning Butternut Squash Step-by-Step
Follow this visual guide for a step-by-step overview of safely pressure canning butternut squash:
| 1. Prep cubes of peeled, seeded butternut squash | 2. Blanch cubed squash pieces in steam for 3 minutes |
| 3. Fill sterilized jars with blanched squash pieces | 4. Top off jars with hot broth, leaving 1 inch headspace |
| 5. Apply lids and screw on bands fingertip tight | 6. Place filled jars on rack in pressure canner |
| 7. Lock lid and vent steam before pressurizing | 8. Process at 11 PSI for recommended time based on altitude |
| 9. Allow canner to depressurize naturally | 10. Test jar seals after 12-24 hours |
| 11. Label sealed jars and store in cool, dark place up to 1 year | |
Tips for Safely Canning Butternut Squash
Follow these tips for safely pressure canning butternut squash at home:
– Use fresh, undamaged squash. Do not can pieces with mold, mushy spots, or other signs of spoilage.
– Adjust pressure and processing time based on your altitude. Use 15 PSI if you live 1,000 feet or more above sea level.
– Only make one jar size per pressure canner load. Mixing pints and quarts affects heat distribution.
– Let pressure drop naturally. Do not use quick release or cold water baths to decrease time.
– Wait 12-24 hours after processing before testing jar seals. This allows the contents to settle.
– Label all jars with contents and date. Store in a cool, dark place up to 1 year.
– If any jars fail to seal, refrigerate and consume quickly or reprocess within 24 hours.
Common Problems in Canning Butternut Squash
Avoid these potential problems when pressure canning butternut squash:
Not venting steam properly
Failing to vent steam for the recommended 10 minutes before pressurizing can lead to air pockets and inadequate heating. Vent according to your canner’s instructions.
Incorrect headspace
Too much or too little headspace can affect jar seals. Always leave recommended 1-inch headspace for butternut squash.
Lowering pressure too quickly
Releasing pressure too quickly after processing prevents contents from finishing cooking. Allow canner to depressurize naturally.
Loose jar lids
Lids must be clean and centered properly on jars. Screw bands on just fingertip tight before processing. Overtightening can distort lids.
Storing jars improperly
Do not store jars above 95°F or near direct sunlight. Temperature fluctuations and light exposure can affect seals and food safety.
Conclusion
With the proper techniques, equipment, and care, butternut squash can be safely preserved at home by pressure canning for enjoyment all year long. Always use up-to-date, tested recipes from trusted sources and follow instructions precisely for each step of the canning process. Pressure canning is the only safe method for low-acid foods like butternut squash. Take time to learn how to use your pressure canner properly and double check headspace, pressure, venting, and processing times for your altitude. Practice strict hygiene, and never taste or eat from jars that fail to seal or appear spoiled. With some care and planning, you’ll be able to enjoy delicious, nutritious butternut squash canned straight from your garden or local farmers market.