Recipe Wednesday: How to eliminate “Flat Sour” in Canning

Excerpt from 1946 canning cookbook

What is Flat Sour?

Three vegetables, most generally canned, are tomatoes, corn and peas.

Classified by length of processing time, the difficult vegetables are corn, peas and lima beans. These three, with one or two others, such as beets and string beans, often develop “flat sour.” This is experienced more frequently by those who can in glass than in tin because it is impossible to cool glass jars as quickly as tin cans.


Do not permit produce to become heated in sacks and boxes which have no means of ventilation. Sweating and overheating develop conditions favorable for the growth of this “flat sour” organism.

Being one of the “thermophilic,” as its name signifies, it can stand a great deal of heat, and is seldom destroyed in processing. It usually develops at a temperature of 110 to 150 degrees Fahrenheit. There are also species of the “flat sour” which develop at lower temperatures.

Heat cans quickly, cool cans quickly, and little difficulty with this persistent organism will be encountered. Fresh products, canned immediately, quickly heated, processed the required length of time, and cooled quickly, will solve most “flat sour” difficulties.

Better Homes and Gardens Special Interest, Kitchen & Bath, September/October 2008 Issue

Putting sealed cans of vegetables which were cooked in a pressure cooker into a cold water bath for quickest cooling 1940 (Russell Lee, Library of Congress)

Lima Beans

Use Plain cans

The small, tender beans are best for canning. Wash, hull and sort. Put in kettle with just sufficient water to cover. Bring to a boil and pack hot into cans. Add 1 teaspoonful of salt, and, if desired, 1 teaspoonful of sugar to pint can. Seal with Home Can Sealer.

Process No. 2 Cans 50 minutes at 10 pounds pressure and No. 3 cans 60 minutes at 10 pounds pressure. Remove, cool quickly in cold water. Dry, label and store.


Use C. Enameled or Plain Cans

Shell and wash fresh, young peas. Discard hard and nearly ripe peas. Put into kettle, cover with water, bring to a boil. While hot, fill No. 2 cans to ½ inch from top. If can to too full, some of the peas will burst, clouding the liquor. Add 1 teaspoonful of salt and 1 teaspoonful of sugar to No. 2 can. Seal with Home Can Sealer.

Process No. 2 cans 40 minutes at 10 pounds pressure. Process large, overripe peas about 10 minutes longer. Cool quickly. Dry, label and store.

All American Flywheel Tin Can Sealer

  • Constructed of cast aluminum with heavy duty gear train.
  • Flywheel handle is easier to turn.
  • Configured to seal No. 2 can.
  • Contact seller for other can sizes.
  • Made in the USA

About Donna R Causey

Donna R. Causey, resident of Alabama, was a teacher in the public school system for twenty years. When she retired, Donna found time to focus on her lifetime passion for historical writing. She developed the websites www.alabamapioneers and All her books can be purchased at and Barnes & Noble. She has authored numerous genealogy books. RIBBON OF LOVE: A Novel Of Colonial America (TAPESTRY OF LOVE) is her first novel in the Tapestry of Love about her family where she uses actual characters, facts, dates and places to create a story about life as it might have happened in colonial Virginia. Faith and Courage: Tapestry of Love (Volume 2) is the second book and the third FreeHearts: A Novel of Colonial America (Book 3 in the Tapestry of Love Series) Discordance: The Cottinghams (Volume 1) is the continuation of the story. . For a complete list of books, visit Donna R Causey

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One comment

  1. My Mothers name was Rosella Smith and My Dad was John Wesley Willis

    My grandparents were Frank Willis and Monroe Smith.

    I love these news letters and look forward to getting them. My grand parent was born in the 1800’s

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