Safe Preserving: NEW on canning lids

Image courtesy of the National Center for Home Food Processing and Preservation.

Image courtesy of the National Center for Home Food Processing and Preservation.

What’s new in the world of canning? For some people, canning jar lids are the hot topic of the day.  Recipes supported by UW-Extension recommend standard 2-piece metal lids for home canning. Last year Jarden Brands (manufacturer of Ball and Kerr-branded products) began instructing consumers that their lids no longer had to be pre-warmed prior to placement on the jar. Since treatment of lids has long been important in jar sealing, it is a good time to review this topic.

The material that coats the metal on many home canning lids has been reformulated in order to remove the chemical bis-phenol A or BPA. While there have been no scientifically documented health issues linked to BPA in home canning lids, companies such as Jarden took the precautionary step of reformulating the materials in the lids.

Because of the new lid formulation, Ball/Kerr no longer require pre-heating of lids. New boxes of lids from Ball/Kerr indicate that the lids should just be washed and set aside for applying to jars.  Most of the lids manufactured in the United States are made by Ball. If you buy lids in bulk or are otherwise unsure how to pre-treat lids for canning, it can be important to note that some consumers have noticed better sealing (fewer seal failures) if the new lids are lightly pre-warmed prior to use.  Jarden indicates that lids may be pre-warmed without threatening seal failure; boiling will thin the sealing compound and cause lids not to seal.

Here are some tips for success:

  • Use 2-piece metal lids for home canning. The design of home canning lids allows air to escape during canning, helping to form a vacuum seal and ensuring a shelf-stable product.
  • Use lids only once. The newer lids have a thinner application of sealing compound. They should not be reused.
  • Lightly pre-warm lids in simmering water, 180°F. Do not boil!  Many years ago, Kerr lids were boiled prior to use to soften the sealing surface. This is no longer necessary and will actually harm the sealant and cause seal failure. I have found that a small crock pot is a great way to heat lids without getting them too hot.
  • Store lids in a cool, dry location. The sealing compound can crack and become brittle if the lids are stored in a hot, dry location. Purchase new lids every year, if possible. Old lids may cause seal failure. If you prepare more lids than you need, be sure they are dry before storing then until your next canning event.
  • Take care to avoid scratching the lid surface. Lids are actually delicate. The sealing surface and the compound covering the metal lid can be easily scratched. Don’t use tongs to retrieve lids from warm water. Instead, opt for a ‘lid wand’ or, my favorite, a telescoping plumber’s magnet (pictured right) to quickly and efficiently retrieve lids from water.

    Telescoping plumber's magnet. Available at most hardware stores.

    Telescoping plumber’s magnet. Available at most hardware stores.

  • Tighten lid bands ‘finger tip tight.’ The purpose of the band is to hold the light lightly in place so that it drops down onto the jar rim once air is removed from the jar. If bands are tightened too tight, you risk jar breakage or seal failure.

The new lids function equally well for boiling water canning and pressure canning. The National Center for Home Food Preservation still does not recommend reusable canning lids for home use.  Safe preserving! Barb




Safe Preserving: Announcing – Put it Up!

Image courtesy of Clemson University.

Image courtesy of Clemson University.

Just in time for program planning, the National Center for Home Food Processing and Preservation has developed lesson plans for teaching youth how to preserve food at home. The Put it Up! Food Preservation for Youth  curriculum is a series of informal educational lessons that guide youth to explore and understand the science of safe food preservation.

The hands-on food preparation activities are designed for middle school ages, however they are can be adapted for 4th – 12th graders depending on prior experience with food preparation and classroom science.

Who is getting involved? After-school group leaders, 4-H educators and volunteers, summer camp instructors, parents, and other Extension educators will find the lessons a great way to engage youth in food preservation.

How are the lessons organized? The series is composed of six different food preservation methods:

  • boiling water canning
  • making jam
  • pickling
  • freezing
  • drying
  • pressure canning

Each method is divided into a beginning hands-on activity and an advanced hands-on activity. Activities may stand alone or be sequenced for cumulative learning. In addition to step-by-step procedures, reflection questions, and ideas for experimentation, each method also includes additional activities: a science-based fill-in-the blank challenge, a history-based word search, a glossary, a resource list, a knowledge test, and more!

The lessons are free to those who register online: Consider adding this to your resource database.  Safe preserving! Barb

Safe Preserving: Canning Your Own Salsa Recipe

salsaI am often asked by consumers how to take that family-favorite salsa recipe into a product that is canned and on the shelf to enjoy during the height of winter. Questions like this are prominent in the minds of researchers that develop tested recipes for home canners.

Salsas typically are mixtures of acid ingredients such as tomatoes or other fruits, vinegar, and lemon juice, and low-acid ingredients such as peppers, onions, and other vegetables. Salsas, pickles and other similar products are examples of  acidified foods; with added-acid or acid ingredients to reduce the pH to 4.6 or below, these products can be processed in a boiling water canning. If the product pH is above 4.6, then it must be processed in a pressure canner as a low-acid product.

Once a researcher knows the final pH of the product, the hard part is establishing a safe processing time. It is the type and proportions of ingredients, preparation method, product characteristics such as thickness, and size and type of container that will determine what the canning process time should be.  There is no way to tell someone how to can a homemade salsa without all of this information. The National Center for Home Food Preservation has a fact sheet that explains in detail how researchers conduct heat penetration studies in order to establish thermal (heat) processes for new canning recipes.

All recipes in the current USDA Complete Guide to Home Canning (2009) and Extension recipes from the National Center for Home Food Preservation and University of Wisconsin-Extension are tried and tested, and processing times decided upon for the recipe as provided and research-based.  Extension recommends recipes and procedures we know to be safe, and encourage consumers to use current, tested, science-based home-canning recipes from reliable sources.

Tested recipes for home canning of salsa are available from:

Ball Canning also has some tested salsa recipes available, however, many of these recipes use a seasoning packet that Ball markets for salsa. This seasoning packet is not necessary to manufacture safe salsa. If you do use a Ball salsa mix, you must carefully follow the directions on the packet.

There are no tested recipes for pressure canning salsa, for canning salsa in quart-size jars, or for adding ingredients such as corn or black beans to home-preserved salsa. Safe modifications that can be made to home canning recipes are outlined in an earlier blog. If you want to make recipe modifications to salsa, consider freezing your salsa for long-term storage. Freezing is a safe way to preserve an untested salsa recipe while protecting your family’s health.

A more detailed description of the science behind canning your own salsa recipe is available from the National Center for Home Food Preservation.  Safe preserving! Barb

Safe & Healthy: Summer without Salmonella

The Partnership for Food Safety Education is launching a campaign to get everyone ready for a SUMMER WITHOUT SALMONELLA.  What a great idea! Illnesses caused by Salmonella spike in the summer.  Here are some surprising facts about this group of harmful bacterium:

  • Salmonella causes about 1.2 million illnesses in the United States every year – more than any other pathogen!
  • For every confirmed case of salmonellosis, there are an estimated 30 unconfirmed cases.
  • There are 2000 Salmonella serotypes that can cause human disease.
  • The number of infections linked to Salmonella have not declined in the past 15 years.
  • Salmonella Typhimurium is known to be resistant to five microbial agents.
  • Salmonella outbreaks have been linked to a variety of food items from raw produce to frozen processed foods.

Just 4 Quick Tips from the Partnership for Food Safety Education and we can all be on our way to a goal of a summer without this deadly pathogen.

SummerWithoutSalmonellaHEADERIt’s easy!

  • Don’t rinse raw chicken. This spreads germs around the kitchen and is not a food safety step.
  • Cook chicken to 165°F. Always use a food thermometer.
  • Wash your hands. Before eating and before and after handling food.
  • Always use soap. Wash hands for 20 seconds with soap and warm water, scrub well!

Stay food-safe for a fun summer! Barb


Safe Preserving: Reusable Canning Lids

Jar with Tattler lid and gasket. Used with a standard metal ring band during processing.

Jar with Tattler lid and gasket. Used with a standard metal ring band during processing.

I have received a lot of questions about the use of reusable lids for canning.  Currently, Extension does not recommend the use of this type of lid. There is research underway at the University of Georgia to determine whether  we can recommend the use of these lids in the future.  That said, it’s good to know about different types of canning equipment in case you are asked to comment.

Perhaps the most commonly found brand of reusable canning lid is the Tattler® lid. This lid is very similar to a traditional metal canning lid that Extension does recommend. Tattler lids are plastic and reusable. They are used with a separate rubber gasket. With the traditional metal lid and the Tattler lid, you still use the standard metal ring to secure the lid to the jar.

Why do some individuals ask about the Tattler lids? The lids are reportedly better to use for home canning. Let’s look at some of the claims that the lid company makes. Tattler_10

  • BPA free. Several years ago, the chemical BPA (bis-phenol A) was in the news as a component in plastics ranging from baby bottles and baby toys to the plastic lacquer lining metal cans.  There was concern over the safety of the chemical, but the Food and Drug Administration has done extensive research and there is no cause for concern. Regardless, regular metal canning lids are also BPA free, so there is no advantage gained by using the Tattler lids.
  • Made in the USA. Standard Ball and Kerr metal canning lids are also made in the US, many right here in Wisconsin.
  • Indefinitely reusable. This claim on some websites is unfounded. The gaskets with the Tattler lids will wear out. Tattler lids may be used 10 times, not indefinitely. Metal canning lids are 1-trip lids, they are used once and then discarded or recycled to use when storing food, etc. Reuse is a benefit to the Tattler lids.
  • Use for hot water bath and pressure canning. Standard metal lids can also be used for both boiling water canning and pressure canning.
  • Avoid spoilage due to acid corrosion. High quality metal lids, like those from Ball and Kerr, do not present a corrosion risk. There is no advantage to using Tattler-style lids.
  • Made of FDA approved materials. Standard metal canning lids are also made of FDA approved materials.
  • Dishwasher safe. Standard metal canning lids are also dishwasher safe.

Based on standard pricing, the cost of a Tattler lid is ~$0.85 per lid; the cost of a standard canning lid (not purchased in bulk) is ~$0.21 per lid.  After 4 years of use, you would recover the cost of your investment in Tattler lids and save  money over the remaining 6 years that you use these lids. Your up-front investment, however, can be steep. For a home canner who puts up as few as 100 jars a year (and most of us preserve many hundreds of jars), your initial investment is ~$85.00 in lids alone. The Tattler lid must remain on the jar while it is sitting on the shelf; it can be replaced by a used metal lid once opened and moved to the refrigerator.

Later this year, I hope to be able to share information based on research-testing of the Tattler lids . Safe preserving! Barb


Safe & Healthy: When Grilling, Temperature is Key!

Image courtesy of Ohio State University.

Image courtesy of Ohio State University.

There are many aspects to managing a holiday picnic, including cooking meat to a proper temperature to help prevent foodborne illness. The USDA has simplified meat cooking temperatures so your holiday cookout will be both safe and tasty. These new temperatures are often lower than previous recommendations, but include a rest time. After you remove meat from the grill, set larger pieces aside to rest. As it rests, the meat juices will penetrate throughout, making for a juicer product, and the temperature will continue to rise, helping to ensure safety as well.

Safe minimum cooking temperatures

  • Ground meat – beef, pork, veal, lamb – 160ºF (no rest time)
  • Ground poultry - chicken, turkey – 165ºF (no rest time)
  • Fresh beef, veal, lamb – steaks, roasts, chops – 145ºF (3 minute rest time)
  • Fresh poultry - chicken, turkey – whole or pieces – 165ºF (no rest time)
  • Seafood – fin fish, shrimp – 145ºF (no rest time)

Key to cooking to a safe temperature, is having a thermometer and using it.  The food thermometer thermometer_in_steakshould be placed in the thickest part of the food and should not be touching bone, fat, or gristle. Begin checking the temperature toward the end of cooking, but before the food is expected to be “done.” Make sure to clean your food thermometer with hot soapy water before and after each use! thermometer_in_burger_cutout

To brush up on grilling food safety, refer to USDA fact sheets:

Happy (and foodsafe) 4th! Barb

Safe Preserving: Canning on Portable Burners

Presto dial gauge pressure canner.

Presto dial gauge pressure canner.

If you have a smooth cooktop or a nonfunctional stovetop you might find yourself looking for options for home canning. The National Center for Home Food Preservation offers some tips on deciding what to do.

If you consider installing a range top just for canning, remember to consider  expense of installing the utilities to support  a second range top. As for portable burners, they are not all alike and not all portable burners are appropriate for canning.  First of all, check the burner manufacturer’s specifications and directions or contact their customer service department for more specific information about the appropriate use of a particular burner for canning.

A few basic guidelines for you to keep in mind when selecting a portable burner for canning purposes:

  • The burner must be level, sturdy, and secure. Look for enough height to allow air to flow under the burner, but not such that it will become unsteady with a full, heavy canner resting on it. One we have tested was about 4 inches high off the counter top, on short legs that allowed air circulation underneath but was plenty stable.
  • Look for a burner diameter that is no more than 4 inches smaller than the diameter of your canner. In other words, the canner should not extend more than 2 inches from the burner on any side.  This is a common recommendation, but also make sure this is the recommendation for your canner brand.
  • Use caution when canning on outdoor gas burner/ranges over 12,000 BTUs, especially with pressure canning. Your pressure canner can be damaged if the burner puts out too much heat. Higher BTU burners could also produce so much heat that the recommended come-up time for canning could be altered, potentially producing an unsafe final product.
  • For electric burners, you want the wattage to be about equal to that of a typical household range large burner.  A burner with wattage of 1500W/120V is generally a minimum for boiling water canning; household range burners are more typically 1750W or higher and this kind of wattage may actually be a better choice if you can find it. [NOTE: The National Center is not able to recommend use of a portable electric burner for pressure canning.]

Remember that the housing for the electric burner must hold up to the high heat of canning for long periods of heating without damaging the counter top from reflected heat. Be sure to consider this in making your decision.

The National Center recommends consulting with the manufacturer before purchasing, or using, any type of portable burner for home canning. Safe preserving! Barb


Safe Preserving: Flavored Vinegars

flavored_vinegarFlavored vinegars are very easy to prepare and delicious with summer-time salads. They are favored by chefs for adding excitement to special dishes. Cooking at home is also enlivened by the blended flavor of vinegar and herbs, fruits, vegetables and/or spices. And because they are naturally so high in acid, flavored vinegars allow more creativity than other types of home canning – you may choose fancy bottles and non-standard lids for an especially festive look.

Getting Ready

  • Choose festive glass containers that will showcase your product. Use only glass containers, not plastic or metal. Carefully wash in warm, soapy water and rinse well. Prior to filling, sanitize by boiling in water for 10 minutes.
  • Choose a tight-fitting lid or cap. Use non-corrodible metal, plastic, or even cork. Wash lid or cap and sanitize prior to using. If using corks, use new cords and dip in and out of boiling water 3-4 times prior to sealing bottles.


  • Allow 3-4 fresh herb sprigs per 2 cups of vinegar. Use only the best leaves or stems for best presentation and flavor. Rinse well, but gently, in water and blot dry. For best keeping quality, dip in a dilute bleach solution after rinsing with water: 1 teaspoon of bleach in 6 cups of water (do not use scented bleach). Rinse again in cool water and blot dry. Or use dried herb, 3 Tablespoons per 2 cups of vinegar.
  • Favorite fruits for flavoring vinegars include raspberries, blackberries, strawberries, peaches, pears and the peel of lemons and oranges. Consider combining fruits with herbs such as mint or spices such as cinnamon. Rinse fruit well and blot dry. Allow 1-2 cups of fruit per 2 cups of vinegar.
  • Other popular flavorings include peeled garlic cloves, jalapeno or other hot peppers, green onions, peppercorns or mustard seeds.

Preparing flavored vinegar  Place herbs, fruits, vegetables and/or spices in sterilized jars. Heat vinegar to just below the boiling point (190°-195°F), and pour over the flavoring ingredients, leaving 1/4″ headspace. Wipe jar or bottle rim and seal tightly. Let sit to cool.

More information on preparing flavoring agents for vinegars, and tips on preparing high quality flavored vinegars can be found in the University of Georgia’s publication Preserving Food: Flavored Vinegars. Safe preserving! Barb

Safe & Healthy: Friendship Bread & Sourdough Starters

breadloafIt wasn’t long ago that my daughter came home from school bearing a plastic bag with a mass of sticky dough and asked me to ‘feed it’ and bake bread for her class once it had grown ‘big and strong.’  My daughter knows that I am an avid bread baker, but this was  my first experience with ‘friendship bread.’ Friendship bread is made using a yeast-based sourdough starter that is kept for an extended period of time, often passing from family to family. Another type of bread that is increasingly popular is an extended-rise no-knead bread.

As someone who at least thinks they know something about food safety, I first did some research. Recent nationwide foodborne illness outbreaks have been linked to traditional bread-making ingredients: first, contaminated flour was tentatively linked to the presence of E. coli O157:H7 in Nestle cookie dough that sickened at least 69 people in 30 states and led to a nationwide recall of prepared, refrigerated cookie dough in 2009; more recently, thousands of eggs were recalled in 2010 due to possible contamination with Salmonella. Since no one wants to share illness as they share friendship bread starter, or sicken their family as they prepare an extended-rise bread, it’s time to ‘think safety’ when preparing, or sharing, these products.

Here are some suggested steps to food safety when preparing, and ‘gifting’ friendship starters:

  • Choose the proper starter. It is difficult to prepare a sourdough starter from ‘scratch’. Microorganisms naturally present in the ingredients may not be the ideal ones for producing a good starter, and will be slower to produce the acid which is needed for safety. Instead of the ‘friendship style’ starter, choose one that contains yogurt or cultured buttermilk as an ingredient, placing acid-producing bacteria in the starter from the beginning and helping to inhibit any pathogens or spoilage bacteria which may be present.
  • Check to see that a starter is still good. A good starter has a pleasant sour smell and is bubbly. Discard any starters which smell bad, turn reddish or orange in color, or grow mold. Never taste the raw starter, use your other senses to detect if the starter is still good.
  • When possible, store a starter in the refrigerator. Try a recipe that provides for an initial fermentation of up to 8-10 hours at room temperature, after which the starter is maintained in the refrigerator. Even when a recipe does not suggest refrigeration, once activated, the starter can be placed in the refrigerator and simply warmed to room temperature for a few hours before baking.
  • Take care with extended rise, non-starter doughs. If preparing an extended-rise dough which does not contain a starter, never taste the raw dough, take extra care to maintain kitchen cleanliness and prevent cross contamination, and cook the dough thoroughly.

For more information on Friendship breads and sourdough starters, refer to the UW-Extension fact sheet. Stay safe and healthy! Barb

Safe Preserving: Treating Jars before Canning

Image courtesy of the National Center for Home Food Preservation.

Image courtesy of the National Center for Home Food Preservation.

Why do Extension recipes always call for washing jars before you use them for canning? And why do some recipes call for sterilizing jars, what is the difference? New canning jars out of the box are not necessarily clean. Being in a box or covered in plastic wrap is not the same as a sterile environment. In addition to contamination by microorganisms that cannot be seen with our bare eyes, packaged jars may accumulate dust, small bits of debris, and even chips of glass in the case of breakage (which does happen sometimes in all the steps of transport from factory to store to home).

Whether brand new or re-used many times over, you should always wash jars just prior to filling them when canning. Wash jars in a dishwasher or by hand, using detergent and rinsing well. Clean jars should then be kept warm prior to filling.  You can leave them in the closed dishwasher after the cycle, use your canner as it is preheating, or create a separate water bath that will keep the jars both clean and warm.  I grew up in a household where my Mom kept jars warm in the oven, and I myself use a Nesco roaster – any of these options will work. The warmth of the jar will help the seal to form, safely preserving the bounty of the harvest for months to come.

Washing is also a good time to inspect jars for any cracks or chips, discarding or re-purposing those jars for non-canning uses if any imperfections are found. If you see scales or film from hard water left on your jars, then remove this by soaking jars for several hours in a solution containing 1 cup of vinegar (5% acidity) per gallon of water.  [Hint: 1/4 cup of vinegar added to the canner water will help prevent build-up during canning.]

In order to actually sterilize jars, they need to be submerged in (covered by) boiling water for 10 minutes. Recipes call for pre-sterilizing jars for short processes, less than 10 minutes. When a process time is 10 minutes or more, the jars will be sterilized during processing in the canner.

And remember, Extension recommends that you use jars designed for home canning with 2-piece lids.  While it might be tempting to re-purpose an old mayonnaise or sauce jar for canning, these jars are more susceptible to breakage and may not take a 2-piece lid.  Safe preserving! Barb


Safe and Healthy: Preserving Food at Home is part of the University of Wisconsin-Extension For Your Information Network. Protected by Akismet. Blogging software based on WordPress.
© Board of Regents of the University of Wisconsin System | Terms of Use | Privacy Policy