Dear TEAM: I have been canning salsa for a few years and I have never processed mine in a hot water bath. I am wondering if I have been lucky that I’ve never made anyone sick. I have been doing a lot of reading regarding pH levels as well as botulism in homemade salsa. I was hoping you could give me some insight into the safest way to can salsa. — E.D.
Dear E.D.: There are four important factors to keep in mind when canning foods: micro-organisms, acidity, temperature and time.
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Invisible micro-organisms, including bacteria and yeasts, are in the air and on food. All food has natural enzymes that cause the food to over ripen and spoil. To prevent food spoilage, these micro-organisms and enzymes must be destroyed. Our three weapons are acidity, temperature and time.
Food is either high or low acid. The pH level is a measure of a food’s acidity, with 4.6 or lower meaning a food’s acidity is high. A high acid environment inhibits the growth of bacteria and other spoilage organisms, but it is not enough to preserve food.
Heat must be applied for a specific length of time to inactivate enzymes, yeasts and micro-organisms. This is called heat processing.
High acid food includes fruits, fruit juices, jams, jellies, fruit spreads, pickles, relish, salsa, chutney and tomatoes with added acid (lemon juice or vinegar).
All high acid foods must be heat processed to 212 F (100 C). This is the temperature of boiling water and can be achieved efficiently in a boiling water canner. Individual recipes should indicate the length of time to process the food.
Low acid food includes vegetables, meat and game, poultry, seafood, soups, stews, tomato-vegetable sauces and tomato meat sauces.
This food must be heat processed at temperatures of 240 F (116 C) for a specified length of time to destroy the growth of Clostridium bolulinum spoilage organisms that can be present in any food.
This temperature can be achieved only in a pressure canner.
Clostridium bolulinum is destroyed at boiling temperatures, but it has the ability to form hardy spores that can survive the boiling treatment. These spores thrive in a low acid environment without air such as in a sealed jar because these spores give off a deadly toxin as they grow.
As boiling water canners cannot reach this temperature, low acid food must be processed in a pressure canner. Clostridium bolulinum spores do not grow in the presence of acid so high acid food can be safely processed in a boiling water canner.
Tomatoes were traditionally a high acid food but many new varieties are considered low acid. To adjust for this, an acid like lemon juice or vinegar is added to tomato- based recipes such as salsa.
When canning any foods, it is important to use recipes that have been tested, using current canning practices. Homecanning.ca is a reliable source of information.
Diane’s Salsa
This is a large batch salsa recipe that our family enjoys.
- 10 – 12 c. tomatoes, 2.5 – 3 L chopped (4 – 4.5 L whole tomatoes)
- 4 c. onions, chopped 1 L (5 – 7 large onions)
- 4 c. yellow peppers, 1 L chopped (5 mediums)
- 1 c. red peppers, 250 mL chopped (1 large)
- 2 c. green peppers, 500 mL chopped (2 large)
- 2 c. celery, chopped 500 mL
- 3 – 6 hot jalapeno peppers (3 for mild, 6 for medium)
- 6 cloves garlic, chopped
- 2 c. vinegar 500 mL
- 5 cans garlic or herbs 5 x 156 mL and spices tomato paste
- 2 tsp. paprika or 10 mL smoked paprika
- 2 tbsp. salt 30 mL
- 1 tsp. oregano 5 mL
- 2 tbsp. sugar 30 mL
- 2 tsp. cumin 10 mL
- 2 tsp. coriander 10 mL
- Optional:
- 1/4 – 1/2 c. hot sauce 60 – 125 mL or Tabasco sauce
Place clean sealers on a rack in a canner, then fill canner half full with water. Heat to boil to sterilize sealers. Place metal sealing lids in a pan of hot, not boiling water.
Place a few tomatoes in a large bowl, add boiling water, allow it to sit one minute, then place tomatoes in cold water. The tomato skins will slip off easily.
Chop tomatoes and set aside. For chunky salsa, chop by hand or use a food chopper. For a finer texture, use a food processor. Chop onions, peppers and garlic in a food processor.
Place ingredients, except tomatoes and hot sauce, in a large pot. Mix and boil for 10 minutes, or longer to desired thickness. Add chopped tomatoes and boil for one minute. Taste and add hot sauce or tabasco sauce. Mix well.
Ladle hot salsa into a hot jar, to within 1/2 inch (1 cm) of top of jar (headspace). Using a non-metallic utensil, remove air bubbles and adjust headspace. Wipe jar rim to remove any food residue.
Centre hot sealing lid on clean jar rim, screw band down until resistance is met, then increase to fingertip tight. Return filled jar to rack in canner. Repeat for remaining salsa.
When canner is filled, add enough water to covered jars by at least one inch (2.5 cm) of water.
Cover canner and bring water to full rolling boil before starting to count processing time. At altitudes up to 1,000 feet (305 m), process 15 minutes. See altitude chart.
When processing time is complete, remove canner lid, wait five minutes, then remove jars without tilting and place upright on a protected work surface. Cool upright, undisturbed, for 24 hours. Do not retighten screw bands. After cooling, check jar seals. Sealed lids curve downward and do not move when pressed. Remove screw bands, wipe and dry bands and jars and label. Yields: 18–20 pints. Source: Diane MacDonald, www.bernardin.ca.
Betty Ann Deobald is a home economist from Rosetown, Sask., and a member of Team Resources. Contact: team@producer.com.