This page is all about canning asparagus. If you were looking for a canned asparagus recipe follow this link to see various options.
Home canning asparagus produces a much more acceptable product than buying the tinned varieties. Having said that we think that the tinned White Asparagus can be very good. The jury is still out in our house on bought tinned green asparagus for anything much more than as a filler in a quick everyday soup! So try this canning method and form your own conclusions.
As with all methods of preservation canning is going to produce the best results if the raw material is really fresh. It’s the perfect way to avoid waste at the height of the season when you can’t keep up with the rate it is growing. Do however consider the alternatives of dried asparagus or freezing asparagus.
Canning must be carried out correctly to ensure that the bacterium the bacterium Clostridium botulinum is killed. This bacterium may cause botulism a deadly form of food poisoning so it is important that the correct temperatures and pressures are used for the correct periods of time. Different times, temperatures and pressures are required according to the acidity of the food to be canned and the size and shape of the vessels being used. Acidity reduces the ability of the bacterium to reproduce. Asparagus is not an acidic plant unlike some fruits so needs to either be canned under pressure to achieve the temperatures required or have acid added (picking). Fruits with a reasonable level of acidity can be canned at 100 degrees C.
There are no safe ways to can asparagus in a boiling water canner unless it is pickled. You must use a pressure canner.
If you have not used a pressure canner before or are at all unsure about how to use it please read the following information on the National Center for Food Preservation website. It is really important that you get this right!
If you live at high altitude (above 1000 feet) water boils at a lower temperature and you will need to adjust the pressure to compensate for this. Again the National Center for Food Preservation website is a useful source of information.
Approximately 16 pounds of asparagus is needed for a full canner load of 9 pints. That’s quite a lot of asparagus to have excess from one or two days and you want to be canning your asparagus fresh.
1. Pressure cooker
2. Preserving jars with appropriate seal (e.g. Kilner or Mason jars ) – you must use proper preserving jars not used standard glass jars. The standard glass jars that you buy with mayonnaise or similar are not strong enough and may break. Preserving jars have deeper necks and better methods of sealing. These jars are generally sold as ½ pint, pint and quart size.
3. Tools for grabbing and moving the hot jars are available and are very useful
4. Fresh Asparagus!
5. Salt (Optional)
6. Boiling Water
If you don’t have a pressure cooker but still want to try canning asparagus you may like to try making pickled asparagus which can be jarred without the use of a pressure cooker.
1. As mentioned earlier use the freshest product you can and given it a rinse.
2. Cut off the woody ends and cut the spears into 1” lengths unless you wish to can them whole. If canning whole 4” to 6” in length is best but to fit the jars you are using.
3. You can “can” the spears either raw or cooked.
4. To can raw pack the jars raw spears leaving about 1 “ headspace and fitting as many spears in the jar as possible without crushing.
5. To can cooked asparagus cover the spears with boiling water and boil for 2 – 3 minutes. Or steam lightly. Put the hot asparagus into jars again leaving 1” headspace. Be careful not to crush as the cooked asparagus will be more tender.
6. Now is the time to add salt if you want to (this is only a matter of taste and not for preserving purposes) (1 teaspoon salt per quart).
7. Now pour boiling water into the jars just covering the spears but leaving 1” headspace. Put the lids on the jars firmly but do not over-tighten.
8. Put the jars in the pressure cooker and follow your cookers instructions for bringing the jars up to pressure.
Cooking times and pressures for canning asparagus are as follows:
|Table 1. Recommended process time for Asparagus in a dial-gauge pressure canner.|
|Canner Pressure (PSI) at Altitudes of|
|Style of Pack||Jar Size||Process Time||0 - 2,000 ft||2,001 - 4,000 ft||4,001 - 6,000 ft||6,001 - 8,000 ft|
|Hot and Raw||Pints||30 min||11 lb||12 lb||13 lb||14 lb|
|Table 2. Recommended process time for Asparagus in a weighted-gauge pressure canner.|
|Canner Pressure (PSI) at Altitudes of|
|Style of Pack||Jar Size||Process Time||0 - 1,000 ft||Above 1,000 ft|
|Hot and raw||Pints||30 min||10 lb||15 lb|
9. After the appropriate time leave the whole cooker and canned asparagus in its jars to return to room temperature at their own rate. This will take a good while. Do not be tempted to pour cold water over it or any simliar methods to speed up the cooling process!
10. Store in a cool dark place and don't forget to label your jars with the date and what is in the jar!!
We think asparagus canned at home beats the bought tins any time.
The National Center for Food Preservation has been a useful source of information on canning asparagus and also includes information on canning all sorts of other foods.