The role of salt in home canning

Summary of salt’s role in canning

In almost all home canning, salt’s role is flavouring; it is not present in sufficient quantities to prevent spoilage or act as a preservative in terms of safety.

Is it safe to do home canning without salt?

In very many instances, yes.

Any exceptions?

Yes. For safety reasons, items such as fermented foods (e.g. sauerkraut and fermented pickles) must continue to use real salt for the time being.

When is salt not needed for safety

The National Center for Home Food Preservation says,

• Is it safe to can food without salt? Yes. Salt is used for flavor only and is not necessary to prevent spoilage.  ^[1] https://nchfp.uga.edu/questions/FAQ_canning.html#17 ;
• Is it safe to can meat and poultry without salt? Yes. Salt is used for flavor only and is not necessary for safe processing.  ^[2] https://nchfp.uga.edu/questions/FAQ_canning.html#27

Renee Boyer of Virginia Cooperative Extension says, “The use of salt … in … canning …. has no preservative effect except when salt is used in brined and cured products…. Salt is mainly added to enhance flavor.”  ^[3] Boyer, Renee R. Boiling Water Bath Canning. Virginia Cooperative Extension. Publication 348-594. 2013. Accessed March 2015 at https://pubs.ext.vt.edu/348/348-594/348-594_pdf.pdf Page 3.

Salt in canning low-acid foods

Angela Fraser of Clemson University in South Carolina says, “Salt may be added to vegetables and tomatoes before canning. Because its only function is flavor, it can safely be omitted. Canning fruits and vegetables without adding sugar or salt does not affect the processing time or the safety of the product.”   ^[4] Fraser, Angela. Associate Professor/Food Safety Education Specialist. How Canning Preserves Food. Clemson University, Clemson, SC. Accessed March 2015 at https://www.foodsafetysite.com/consumers/resources/canning.html

The Institute of Medicine (US) Committee on Strategies to Reduce Sodium Intake says, “For many foods, reducing the sodium content of the product should not create food safety or spoilage concerns. Such foods include frozen products, products that are sufficiently thermally processed to kill pathogenic organisms (e.g., canned foods), acidic foods (pH < 3.8)”   ^[5] Institute of Medicine (US) Committee on Strategies to Reduce Sodium Intake; Henney JE, Taylor CL, Boon CS, editors. Strategies to Reduce Sodium Intake in the United States. Washington (DC): National Academies Press (US); 2010. 4, Preservation and Physical Property Roles of Sodium in Foods. Available from: https://www.ncbi.nlm.nih.gov/books/NBK50952/

Linda Robbins of Cornell Cooperative Extension writes, “… salt can be omitted for canning tomatoes, vegetables, meats, poultry and seafood since the amount added does not contribute to the safety of the food.” ^[6]Robbins, Linda. Types of salt and salt substitutes in home canning. Herikimer, New York: Times Telegram. 26 August 2016. Accessed October 2016 at https://www.timestelegram.com/news/20160826/linda-robbins-types-of-salt-and-salt-substitutes-in-home-canning

Ball’s web site says, “Can vegetables be safely canned without salt? Yes, vegetables may be canned without salt. The measure of salt called for in most vegetable recipes is too small to help prevent spoilage; it is there only for seasoning. To prepare vegetables with less or no salt, simply omit salt or reduce the amount of salt to taste.”  ^[7] Accessed June 2015 at https://www.freshpreserving.com/tools/faqs

Ball’s Blue Book says, “The amount of salt called for in canning meats and vegetables is too small to help prevent spoilage; the salt is there only for seasoning. Follow recipes for canning low-acid vegetables, meats and poultry, but omit salt. Do not omit salt from seafood recipes.”  ^[8] Ball Blue Book Guide to Preserving. Daleville, Indiana: Hearthmark LLC. Edition 36. 2013. Page 74.

It’s unclear why Ball’s Blue Book says not to omit salt from seafood recipes. Penn State Extension says that you can, when canning seafood: “Salt can be omitted for canning tomatoes, vegetables, meats, poultry, and seafood since the amount added does not contribute to the safety of the food.”  ^[9] Types of Salt and Salt Substitutes in Canning. Penn State Extension. 24 July 2012. Accessed June 2015 at https://extension.psu.edu/food/preservation/news/2012/types-of-salt-and-salt-substitutes-in-canning

Pacific Northwest Extension also says you can leave salt out when canning seafood:  “Lemon juice, vinegar, salt and oil are added to maintain quality (flavour, colour) of canned seafood. You can leave them out…”   ^[10] Canning Seafood. Pacific Northwest Extension. PNW 194. Reprinted 2008. Page 1. Accessed March 2015 at https://whatcom.wsu.edu/fch/documents/pnw194.pdf

Ball does not give its reasons; presumably it is for quality (flavour, colour) as Pacific Northwest explains, rather than safety. In the USDA guide, in the section on canning seafood, salt is listed as optional with most seafood recipes saying something like “Add 1 [Ed: or ½] teaspoon salt to each pint, if desired.”  ^[11] Oysters, United States Department of Agriculture (USDA). 2015. Complete guide to home canning. Agriculture information bulletin No. 539. Available at: https://nchfp.uga.edu/publications/publications_usda.html (Accessed March 2015). Page 5-12 

Salt in canning pickled items, preserves, condiments, etc.

The USDA Complete Guide (2015) says salt is not required for fresh-pack (vinegar) pickle recipes, but that it absolutely is required for safety with fermented pickles:

In the making of fresh-pack pickles, cucumbers are acidified quickly with vinegar. Use only tested recipes formulated to produce the proper acidity. While these pickles may be prepared safely with reduced or no salt, their quality may be noticeably lower. Both texture and flavor may be slightly, but noticeably, different than expected. You may wish to make small quantities first to determine if you like them.

However, the salt used in making fermented sauerkraut and brined pickles not only provides characteristic flavor but also is vital to safety and texture. In fermented foods, salt favors the growth of desirable bacteria while inhibiting the growth of others. Caution: Do not attempt to make sauerkraut or fermented pickles by cutting back on the salt required.” ^[12]United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. Page 1-28.

Patricia Kendall of Colorado State University Extension writes,

Any fresh-pack pickle recipe that calls for as much or more vinegar than water and provides a finished product with at least ¼ cup of 5 percent acid vinegar per pint jar of pickled products can be safely made without salt. Sweet pickles generally taste better without salt than dill pickles. If salt is omitted from fresh-pack dill pickles, try adding hot peppers, herbs and garlic instead. Dill pickles taste better if as little as 0.5 percent salt by weight of entire contents is added. This is the equivalent of ½ to ¾ teaspoon of salt per pint jar of pickles.”   ^[13] Kendall, Patricia. Food Preservation Without Sugar or Salt. Colorado State University Extension. No. 09302. October 2012. Accessed March 2015 at https://www.ext.colostate.edu/pubs/foodnut/09302.html

Oregon State Extension says,

Salt can be removed from most fresh-pack or ‘quick’ pickles without affecting the safety of the product if the recipe contains as much or more vinegar than water or other liquid. In other words, if the recipe calls for one quart water, it should have at least one quart vinegar, as a rule of thumb. Vinegar may even be the only liquid ingredient.”  ^[14] Food Safety & Preservation: Low Salt Pickles. Oregon State University Extension Service. SP 50-533, Revised February 2013. Accessed June 2015 at https://extension.oregonstate.edu/fch/sites/default/files/documents/sp_50_533_lowsaltpickles.pdf

Barb Ingham at University of Wisconsin Cooperative Extension writes,

Use the amount of sugar and salt called for in the recipe, or you can reduce the amount of either of these ingredients in a quick-process pickle recipe as they are added for flavor and not for safety. For safety sake always use the amount of vinegar called for in a tested recipe, using vinegar that is 5% acetic acid (5% acidity).”  ^[15] Ingham, Barb. Safe Preserving: Dilly Beans. Blog post dated 29 August 2013. Accessed June 2015 at https://fyi.uwex.edu/safepreserving/2013/08/29/safe-preserving-dilly-beans/

Dr Ingham goes on to further say in another publication,

You may safely reduce sugar or salt in any tested quick-process pickle. The amount (and type) of salt listed in a recipe for sauerkraut [ed: a fermented product] or genuine dill (crock) [ed: fermented] pickles can not be changed!…. You can rinse sauerkraut prior to serving and reduce the amount of sodium by 30-40%.” ^[16]Ingham, Barbara. Home Canning: Can I Make Substitutions Safely? University of Wisconsin Extension. 23 June 2015. Accessed June 2016 at https://bayfield.uwex.edu/2015/06/23/play-it-safe-changes-and-substitutions-to-home-food-processing-recipes/

Ball Canning’s FAQ says,

Q: I am following a low sodium diet. May I safely can my pickle recipes with less salt?

A: Only fresh pack (or quick) pickle recipes may be safely adjusted to reduce salt. Reducing the amount of salt or omitting the salt from fresh pack pickle recipes will change the flavor and texture of the finished pickled product. Salt is an important ingredient in fermented and brined pickle recipes. It should not be reduced or omitted when preparing this type of recipe.” ^[17]Ball FAQ. Accessed October 2016. https://www.freshpreserving.com/faqs.html

When is salt absolutely needed for safety in home canned goods?

There are a handful of home canned items for which salt-free alternatives can’t be safely developed. These include fermented and brined items. Don’t try to home can such items with reduced or no salt.

The National Center for Home Food Preservation cautions that “the salt used in making fermented sauerkraut and brined pickles not only provides characteristic flavor but also is vital to safety and texture. In fermented foods, salt favors the growth of desirable bacteria while inhibiting the growth of others. Caution: Do not attempt to make sauerkraut or fermented pickles by cutting back on the salt required.”  ^[18] National Center for Home Food Preservation. Preparing and Canning Fermented and Pickled Foods. Accessed January 2015 at https://nchfp.uga.edu/how/can_06/prep_foods.html

Patricia Kendall of Colorado State University Extension writes, “Always add the amount of salt specified in brined pickles and cured and smoked foods. Salt is needed for the safe preservation of these foods”  ^[19]Kendall, Patricia. Canning Fruits. Colorado State University Extension. No. 9.347. June 2013. Accessed March 2015 at https://www.ext.colostate.edu/pubs/foodnut/09347.html

Barbara Ingham at the University of Wisconsin says, “Do not alter the amount of salt in fermented pickles. Salt concentration is very important in fermentation. Too little salt will cause microbes to grow and allow spoilage to occur.”  ^[20] Ingham, Barbara H. Homemade Pickles & Relishes. Wisconsin Safe Food Preservation Series. University of Wisconsin-Extension Cooperative Extension. B2267. 2008. Accessed March 2015 at https://learningstore.uwex.edu/assets/pdfs/B2267.PDF page 15.

Ball’s web site says, “Salt is an important ingredient in fermented and brined pickle recipes. It should not be reduced or omitted when preparing this type of recipe.”  ^[21] Accessed June 2015 at https://www.freshpreserving.com/tools/faqs

Penn State Extension gives more information,

With the exception of fermented pickles and sauerkraut, salt is an optional ingredient… However, in fermented sauerkraut and brined pickles, salt not only provides characteristic flavor but also is vital to safety since it favors the growth of desirable bacteria while inhibiting the growth of others.  Therefore, do not attempt to make sauerkraut or fermented pickles by cutting back on the salt required… Do not substitute potassium chloride for sodium chloride in fermentation recipes. One way to lower the sodium content of sauerkraut or pickles is to rinse the product with water just before heating and serving. But never do this before canning. Lowering the salt content this way will lower the acid content (raise the pH) and possibly render the product unsafe to eat or quick to spoil.”  ^[22] Penn State Extension. Types of Salt and Salt Substitutes in Canning . 24 July 2012. Accessed January 2015 at https://extension.psu.edu/food/preservation/news/2012/types-of-salt-and-salt-substitutes-in-canning

Linda Robbins of Cornell Cooperative Extension writes,

…in fermented sauerkraut and brined pickles, salt not only provides characteristic flavor, but also is vital to safety since it favors the growth of desirable bacteria while inhibiting the growth of others. Therefore, do not attempt to make sauerkraut or fermented pickles by cutting back on the salt required. ….. Lowering the salt content this way will lower the acid content (raise the pH) and possibly render the product unsafe to eat or quick to spoil.” ^[23]Robbins, Linda. Types of salt and salt substitutes in home canning. Herikimer, New York: Times Telegram. 26 August 2016. Accessed October 2016 at https://www.timestelegram.com/news/20160826/linda-robbins-types-of-salt-and-salt-substitutes-in-home-canning

For the record, the Institute of Medicine (US) Committee on Strategies to Reduce Sodium Intake speculates that it may be possible to substitute potassium chloride and calcium chloride (aka Pickle Crisp®) for salt in fermented products. But they essentially also indicate that testing would be needed to determine quantities required.  Such testing for consistent, certified safety would be beyond the scope of any home kitchen, so one would have to wait for experts to get funding to do some actual research and lab testing on this:

Partially replacing salt with other compounds, such as potassium chloride and calcium chloride, may also be possible in fermented products (Bautista-Gallego et al., 2008; Reddy and Marth, 1991; Yumani et al., 1999). However, these alternatives may be less effective than salt so higher concentrations may be needed in formulations to achieve the same functionality (Bautista-Gallego et al., 2008).”  ^[24] Institute of Medicine (US) Committee on Strategies to Reduce Sodium Intake; Henney JE, Taylor CL, Boon CS, editors. Strategies to Reduce Sodium Intake in the United States. Washington (DC): National Academies Press (US); 2010. 4, Preservation and Physical Property Roles of Sodium in Foods. Available from: https://www.ncbi.nlm.nih.gov/books/NBK50952/

So in the meantime, though one researcher has speculated it might be possible to produce a safe product, no funding that we know of has been made available for research or testing on that question yet, so it remains speculative. Consequently, the home canner should clearly and absolutely avoid, as advised, trying to make reduced or salt-free fermented or brined goods.

See here for information on the use of salt substitutes in home canning.