Category: Food Preservation

Tray Pack for Freezing Food – Why and How

Marlene Geiger 1 Comment

Sometimes a small amount of a frozen food is needed, like a few strawberries for a smoothie, one chicken breast, or a few pepper slices for a soup. By “flash freezing” or using the “tray pack” method, one can easily remove just the right amount of fruit, vegetable, meat, and even baked items needed, rather than thawing larger amounts of food all at once. 

In the food industry, flash freezing quickly chills food items at extremely low temperatures with circulating air. This quick-chill method keeps ice crystals small, preserving the cell structure and preventing moisture loss in the food when it thaws. In the home, flash freezing refers to the tray pack method or practice of freezing individual pieces of food separately spread out on a baking sheet or tray until firm (1-2 hours). When frozen firm, the frozen food is promptly packaged (use containers or bags specific for freezing to prevent freezer burn), leaving no head space, sealed, labeled, and returned to the freezer. This prevents individual pieces of food from fusing together during freezing.

Small ice crystals are desirable in frozen food to preserve texture. Large ice crystals rupture food cells and cause a soft, mushy texture. Small crystals are formed when food is frozen quickly and kept at a constant storage temperature of 0ºF (-18ºC) or lower, making the at-home tray pack method desirable for any foods that come in or can be cut or broken into individual pieces. Raw, cooked, or blanched foods may be frozen using the tray pack method.

Foods that can be Flash Frozen with the Tray Pack Method

Bacteria, molds, and yeast are present on all fresh foods and multiply rapidly between temperatures of 40°F and 140°F (4°C and 60°C). Therefore, fresh fruits and vegetables should be washed with cool water to remove dirt and residues and prepared appropriately, including blanching when necessary, prior to freezing. Other foods should be handled appropriately for their type. Freezing does not kill most microorganisms in food but prevents their growth. When thawed, the surviving organisms on any frozen food can grow again.

  • Fresh fruits: strawberries, blueberries, blackberries, raspberries, cherries, mango chunks, cranberries, grapes, bananas slices, pineapple chunks, peach slices, kiwi slices, gooseberries, currants, rhubarb. Fruits that darken, such as peaches, can be pre-treated with ascorbic acid and drained prior to freezing.
  • Fresh vegetables that do not need blanching prior to freezing: peppers and chilies (seeded, whole, halved, or chopped), onions and garlic (chopped), tomatoes (peeled). [See Freezing Onions, Peppers, and Tomatoes]
  • Fresh vegetables that have been blanched, cooled, and drained prior: green/yellow beans, shelled peas, zucchini/summer squash, whole-kernel corn, carrots, okra, sugar/snap peas and small mixed vegetables. [See How to Blanch and Freeze Vegetables]
  • Individual portions of meat or chunks of meat.
  • Individual scoops of cookie dough.
  • Unbaked, shaped yeast dough. [See Freezing Yeast Dough]
  • Individual portions of baked items.

Trays or baking sheets may be lined with a silicone baking mat (Silpat) or parchment paper if sticking or freezing to the metal is of concern. To ensure that there is sufficient cold air to circulate around the trays to freeze quickly and not raise the temperature of already frozen food, add no more than 2 pounds of food per square foot of freezer space.

Food stored at temperatures of 0°F or below will always be safe to eat. Freezing prevents the growth of the microorganisms that cause food-borne illness. However, frozen foods might lose flavor, texture, or overall quality over time. The FDA Refrigerator and Freezer Storage Chart lists optimum freezing times for the best quality of most foods. Other recommendations from StillTasty.com for items not on the list include:

  • Baked items – 3-6 months
  • Unbaked yeast dough – 1 month
  • Cheesecake slices – 2 weeks
  • Fruit – 1 year
  • Cookie dough – 3-4 months

With the exception of most yeast dough products, it’s best to plan ahead and thaw frozen food in the refrigerator, where it will remain at a safe, constant temperature — at 40°F (4°C) or below. Other options include thawing in cold water or in the microwave. It’s also safe to cook foods from the frozen state; frozen vegetables are commonly prepared this way. Frozen fruit can be served frozen as snacks or used in salads or desserts.

The Mayo Clinic favors flash-freezing of produce, indicating that studies have shown that fruits and vegetables that are appropriately prepared and frozen as quickly as possible retain nutrients better.

For more information on freezing foods, check out The Science of Freezing Foods by the University of Minnesota Extension.

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Food Preservation, Food Safety ,
1 Comment on Tray Pack for Freezing Food – Why and How

Freezer Burn and Food Safety

Marlene Geiger 2 Comments

Have you opened some frozen food to find it has a dry, grayish surface or lots of ice crystals clinging to the surface? This is freezer burn.   Freezer burn is simply the result of air coming into contact with food, and while it may not look appetizing, it is usually safe to eat.

The phenomenon of freezer burn happens when tiny ice crystals on the food’s surface evaporate directly into vapor without first going through the liquid water phase – a process scientifically termed sublimation. This moisture loss or dehydration leaves the food’s surface layers dried out and discolored.

Freezer burn happens when food is not adequately wrapped to remove oxygen, which has a bleaching effect on the food surface. Food stored constantly at 0 °F will always be safe. Only the quality suffers with lengthy or inadequate freezer storage.

The bleaching and moisture loss effect of freezer burn may not make food unsafe to eat, but it certainly affects the taste, texture, and color. Severely freezer-burned food will have an off taste and smell that is especially noticeable. It’s best to toss any food that exhibits severe freezer burn as the quality does not merit the effort to save or prepare it.  Products exhibiting mild freezer burn are usually fine to eat by cutting away the burned area either before or after cooking. Foods with a higher water content are more likely to get freezer burn.

A few simple precautions will help to avoid freezer burn and ensure frozen foods remain at peak condition at time of use and eliminate food waste.  Here’s some tips from the experts:

  • Use freezer-safe containers.  Only use bags, jars, paper and containers that are labeled for freezer use. These products are designed to keep air out.
  • Remove as much air as possible.   Air is the enemy of frozen food.  Vacuum sealers do a wonderful job of removing air.  However, squeezing the contents without smashing will also remove a lot of air.  Some people like to insert a straw into the corner of a zipper bag and pull air out before the final close.  If using freezer containers, crumple a piece of waterproof paper on top of the food to help minimize headspace. This helps prevent freezer burn, ice crystal formation and keeps food pieces from drying out.
  • Maintain the freezer temperature at zero degrees F or lower to help freeze food fast and stay frozen solid.  Foods stored near or in freezer doors or at the top of a chest freezer should be eaten first as these areas are for short-term storage.  Also avoid packing the freezer tightly; air must be able to flow freely around the food.
  • Let foods cool before packaging.  The USDA recommends cooling food as rapidly as possible, either in the refrigerator or in an ice bath.   Cold foods are less likely to trap steam inside the packaging.  Steam, like air, is detrimental to frozen foods as it turns to ice crystals.  Individual blanched vegetables, fruits, meat pieces, and baked goods are best if cooled and then flash frozen on baking trays (tray pack method) for an hour or two before packaging.
  • Store-packaging may be left on meat products but they should be over-wrapped in freezer paper, heavy duty foil or plastic wrap or placed in freezer bags prior to freezing for long-term storage.
  • Label and date.   Freezing keeps food safe almost indefinitely.  However, there are recommended storage times for best quality. Refer to and/or download the FDA Refrigerator and Freezer Storage Chart which lists optimum freezing times for best quality. 

Freezer burn affects food’s quality but not its safety. Even though the food is safe to eat, doesn’t mean one should. Freezer burn fundamentally changes a food’s chemical composition, affecting its flavor and texture.   All foods are susceptible to freezer burn but with proper packaging and freezer management, the problem can largely be eliminated.

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Consumer Management, Food Preservation, Food Safety, Sustanability
2 Comments on Freezer Burn and Food Safety

What About All the Different Brands of Canning Jars and Lids?

Marlene Geiger 43 Comments

With supply and worker shortages and an increase in home canning in 2020 and 2021, new or unfamiliar brands of canning jars and lids began to appear to fulfill consumer needs.  Should consumers trust these new or unfamiliar products?

Canning jars have been around since 1858 when John L. Mason invented and patented a threaded glass jar that became known as the Mason jar and sold under the label, Mason. The original jar has changed very little but has undergone variations in shape and cap design. After Mason’s patent expired, many other manufacturers produced glass jars for home canning using the Mason-style jar with labels such as Ball, Kerr, Atlas, Drey, Mason, Globe, Mom’s, Knox, and Golden Harvest. However, as so often happens, through a process of competition and consolidation, the number of jar producers grew fewer over the years with one company, Newell Brands, acquiring the Ball®, Kerr, Bernardin, and Golden Harvest brands—all familiar brands to consumers.

Mason’s initial form of closure for the glass canning jar was a zinc screw-on cap with a milk-glass liner that screwed down onto a rubber ring on the shoulder of the jar, not the lip. In 1903, Alexander Kerr introduced lids with a permanent rubber seal eventually giving way to the modern two-piece metal lids that seal on the rim.

AnswerLIne has received many calls from clients wanting to know about the new or unfamiliar brands of jars and lids filling the shelf space formerly occupied by familiar and trusted brands. It is important to note that regardless of the brand, USDA canning procedures and processing times are based on scientific testing using standard Mason jars and two-piece metals lids. See Canning in Odd Sized Jars for information on non-standard sized jars.

Here’s what has been gleaned about some of the brands AnswerLine clients have asked about as they have shopped for canning supplies:

Anchor Hocking – Originally known for glass bake- and cookware, Anchor Hocking has re-entered the market with Mason jars.  The jars are made in the USA and per company information are dishwasher safe and perfect for canning, crafting, and storage.  The Anchor Hocking website gives instructions for both water bath and pressure canning with the jars.  Information on the box says the jars, lids and bands are BPA free.  The jars come with lids and bands; no information was found regarding the quality of the lids. 

Country Classics – These jars and lids are made in China and distributed by a company in Ohio.  Per the Country Classics website, www.countryclassicscanning.com, the jars are safe for preserving, crafting, and storing; information is provided for canning by water bath and pressure.  Wide-mouth and regular lids are available.  There is no information about the lids on the website but customer reviews on other sites are mixed. (17 October 2022 Update: numerous AnswerLine clients who have used these lids have reported buckling and seal failure.)

Denali – Offering wide-mouth and regular flat lids, rings, and a pressure canner in their canning line, this company has an engineering team in the US with manufacturing facilities currently in China; per the company website, www.denalicanning.com, this company plans to expand US operations in the near future.  Made of a heavier gauge of steel, the lids have been rigorously tested.  Consumers find that the lids seal well.  If something should not go right with the lids, Denali has a customer resolution option with possible refund.F

ForJars – ForJars has been in business for two year and currently offers only canning lids. Per the company website, https://forjars.co, the lids are made of high-quality metal, which prevents bending and buckling. They have also added some stainless steel material to the composition which prevents the formation of rust. The lids are thicker than many lids with a thickness of 0.18 mm versus 0.10 -0.12 mm of others. The lids work well for either pressure or water bath canning. A high-quality food-grade silicone is used for sealing. Presently the lids are manufactured in China but the company is hoping to open production facillities in Florida by late 2022 or early 2023. Customer service is provided at 941-257-8236 or support@forjars.com. A company representative said that they guarantee their lids and will work to make things right with customers who experience problems. Customer reviews are positive.

Golden Harvest – Golden Harvest is back on the market as a lower-priced line of home canning jars and lids sold by Newell Brands which also owns the Ball®, Kerr, and Bernardin (Canada) brands.  Most home canners find the Golden Harvest jars and lids to be of good quality.  The lids are manufactured in the US. There are no wide-mouth jars in the product line and there is no website for customer service. 

Kilner® – Kilner® is an old English company.  Currently jars are being manufactured in China.  Kilner® makes a variety of jars but the standard Mason jars with two-piece metal lids meet the USDA’s guidelines for home canning jars. They are safe for all types of canning, including pressure.  Kilner® makes their own lids but standard, two-piece, US market, metal lids also fit these jars. The jars may come with recipes but should be ignored; instead, recipes from a reputable source should be used.  The jars come in “ml” sizes, not the US standard half-pint, pint, and quart jars so processing times* need to be considered.  The USDA has not released any recommendations on these jars at the present time, so the rule of thumb is to use the next tested time up. More information can be found on the company’s website, www.kilnerjar.com.

Mainstay – The Mainstay line has been part of Walmart’s offering for several years.  However, it is not clear that Walmart is selling Mainstay canning jars and lids in 2022.  Prior, both jars and lids were made in the USA per product labeling—jars at an Anchor Hocking plant in Monaca, PA and lids by Healthmark LLC Jarden Home—but cannot be verified for recent products (should there be any).  Judging by 2020 consumer reviews, most consumers were satisfied with the lids but did note that the lids were thinner and some of the lids were defective right out of the box. The jars were listed as safe for home canning and freezing but did not specifically mention pressure canning. Mainstay BPA-free plastic lids that fit Mason jars are still available; these lids can be used for storage but not for canning.

Orchard Road – Orchard Road canning jars and lids are made in China following stringent guidelines per a company spokesperson. The plastisol sealing compound is made in Pennsylvania.  A company spokesperson said the entire canning product line has been tested by an independent lab against Ball® products and found to perform just as well.  Azure Marketing asserts that they provide consumers with high-quality canning products at reasonable prices.  The jars are heavy and safe for both water bath and pressure canning.  The lids are BPA-free and can be used with other Mason jars.  They also offer a line of decorative lids. 

PUR Mason – PUR Mason jars and lids are manufactured in China and distributed by the PUR Health Group in Broomfield, Colorado. According to a PUR company official, PUR lids and jars are safe for canning—both water bath and pressure canning.  Jars are lead free.  A new generation of BPA-free lids are now on the market and are heavier, have a thicker coating of enamel on the inside, and have an improved sealing compound for better adhesion.   For more information visit the PUR website.

Tattler – Known for their reusable lids since 1976, Tattler began producing one-time use lids in October 2022.  American made, the disposable lids feature extra thick metal for durability and double BPA-free coating on the underside to deter corrosion.  The flat lids are designed to be used with Tattler’s existing rubber gasket ring which replaces the plastisol used by other companies.  The lids are suitable for pressure canning, water bath canning, steam canning and vacuum sealing. For more information visit the Tattler website or call customer service at (231) 912-0525.

True Living – Both jars and lids are made in China and distributed by a company in Tennessee.  Lighter in weight than some other brands, they are sometimes found in the craft section of stores rather than the kitchen section.  Information on the side of the jar box says “dishwasher safe and BPA free.”  Lids have mixed reviews. 

Weck – Weck home canning jars are made in Germany and are well-known in Europe. Weck also owns the Rex line of preserving jars in Austria. The Weck canning jar system consists of glass jars, glass lids, tabbed rubber gaskets (sealing rings) and metal clamps. The jars are certified for both water-bath canning and pressure canning. The jars come in numerous irregular “ml” sizes—not the US standard half-pints, pints and quarts requiring processing time* adjustments; there are currently no USDA recommendations.  Canning information accompanying the jars has been found to lack modern, research-based procedures so should be discarded in the interest of food safety; tested recipes from reputable sources should be used.  Weck jars and supplies are more costly and are irregular in size; it is not possible to fit the standard 7 (quart) jars in a canner. More information can be found at www.weckjars.com.

There are countless sources for canning lids and it appears that most are made in China.  It is not possible to find reliable information for the no-name brands; reviewer’s comments indicate that lid failure is a problem.  Counterfeit lids are still being sold so it is definitely a “buyer beware” canning market.  While the cost will be higher, supplies are predicted to keep up with demand in 2022.

The USDA, National Center for Home Food Preservation (NCHFP), Iowa State University Extension and Outreach, or AnswerLine do not recommend for (or against) any of these products.  The current recommendation is to use the tested two-piece metal lid system that has been the norm for many years and Mason jars specifically made for the rigors of canning.

__________________________________

*The shape and size of a jar effects the safety of the canning process, so it should not be assumed that recommended processes can be used with jars other than the standard sizes and shapes of Mason-type jars manufactured for home canning. – So Easy to Preserve

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Consumer Management, Equipment, Food Preservation
43 Comments on What About All the Different Brands of Canning Jars and Lids?

Induction Cooking – What You Need to Know

Marlene Geiger 7 Comments

If you’re buying a new range or cooktop, you might be deciding between electric or induction. Induction cooking is currently one of the top choices. It has risen to popularity because of how fast food cooks through the induction method. While both use electricity to cook food and produce the same outcome, the way they get there is quite different. Both are great options, but it’s important to understand the differences between them and which will be the best fit for your cooking needs.

Standard electric cooking sends electric current to open coils or radiant burner elements below the glass or ceramic surface to transfer heat to cooking vessels (pots or pans)  and then to the food inside. This process is known as thermal conduction. It takes time for the burner to heat and transfer heat to the vessel as well as to cool down due to the residual heat that the burners hold; after reducing the temperature, burners take a few minutes to settle to a lower setting and remain hot after burners are turned off.

An induction cooktop or range looks similar to a glass-top electric counterpart but is powered by an electromagnetic field below the surface of the glass cooktop. Instead of passing heat along from surface to cookware to food, induction cooktops heat the cookware directly resulting in even cooking and less loss of energy. The magnetic field reacts with the cookware (which must contain ferrous iron) and transfers heat and energy directly into the cooking vessel. Only the pan, and what’s directly under it, on an induction range gets hot. The surface around it stays cool.  

WHAT ARE THE ADVANTAGES OF INDUCTION COOKING?

  • Cooking is faster.  In general, an induction range or cooktop is 2-4 minutes faster than gas or electric at bringing 6 quarts of water to a boil.
  • Excellent temperature control. Allows for precise temperature adjustments and reduces the chance of burning food.  When you turn the burner off, heat transfer stops immediately, so there’s less of a chance of foods boiling over or overcooking.
  • Easy clean up. Spatters or spills outside of the pan will not bake onto the cooking surface.  There are no burners to take apart and reassemble.
  • More energy efficient. An induction model uses 10% less energy than a smooth-top electric range.
  • Safe.   There is no emission of gas into the air. Cloth objects will not catch on fire because no element is exposed and heat only transfers to items with iron particles in it. Induction units also turn off when the cookware is removed from the heating element so there’s little risk of accidentally leaving it on when cooking is done. Burners accidentally turned on will not get hot.  Fire hazards and risk of burns is reduced.

Electrical appliances such as an induction unit create Non-Ionizing or Low-Frequency EMF. According to the National Cancer Institute there are no current studies that have been able to provide a link that Non-Ionizing radiation causes any adverse health issues such as cancer. In fact the natural radiation emitted from the sun is far more harmful than induction unit could ever be.[1]

The American Heart Association has also deemed the low electromagnetic field safe for patients with pacemakers or medical implants.

  • Reduces kitchen heat and ventilation requirements.

WHAT ARE THE DISADVANTAGES OF INDUCTION COOKING?

  • Cost.  Induction surfaces are an investment since the technology is relatively new.  However, as induction becomes more mainstream, the cost is decreasing.
  • Require cookware containing ferrous iron.  Specifically, that means stainless steel, cast iron, and carbon steel. Pots and pans made from aluminum and copper aren’t compatible. Most confusing of all, some cookware uses a combination of materials in its construction, so its induction status isn’t always obvious. Look for pots and pans marked “induction safe” or “induction compatible.” An easy test to see if cookware is compatible is to see if a magnet strongly sticks to the bottom of the pan.  If a magnet sticks to the bottom, it can be used with induction. 
  • Caution – Cooktops can get hot.   Heat is transferred from the cooking vessel to the glass through conduction, much as a hot pan would transfer heat to a countertop if you set it down to rest.  The glass surface never gets as hot as it would on a traditional radiant electric range but one can never assume that it will be cool to the touch.
  • Unfamiliar sounds.  Some consumers report a buzz or hum on the higher settings resulting from the high energy transferring from the coil to the pan.  There is also the possibility of hearing the element clicking or the fan cooling the electronics. All are common and resolve by turning down the heat or adding food to the pot or pan,, Consumer Reports says that heavy, flat-bottomed pans help reduce the vibrations that cause the buzz.
  • Magnetic field can interfere with digital thermometers.  Consumer Reports suggests the need to resort to an analog thermometer—an old-fashioned solution to a modern problem.
  • Requires a learning curve. Induction cooking takes some getting used to.  Some nuances include: placing the right sized cookware in the center of the heating element in order for it to be properly activated; cookware must be flat-bottomed; the heating element may cut off prematurely or shut off without warning when the pan is shaken or moved; food may overcook until one learns that cookware doesn’t take long to preheat and a lower heat setting is needed to maintain the temperature of food.  Touch pad controls also take time to get used to.
  • Cooktops scratch easily.  Although induction cooktops are made of a durable glass-ceramic composite, they are more prone to scratching if scratchy pans are slid across the surface and even cracking if a heavy pot is set down too hard. Most manufacturers suggest using cookware with clean, smooth bottoms, and to avoid sliding pots and pans across the surface. Sharp tools or abrasive cleaning materials should not be used on the surface.
  • Repairs may be expensive after the warranty period. 
  • A 240V outlet is required.  An induction range or cooktop easily replaces an electric range or cooktop.   If the conversion is from gas, an electrician will need to install the proper wiring. 
  • Requires canners (pressure and water) specifically made for induction cooktops.  Both are available.

While induction cooking is one of the most efficient, safest and precise ways to prepare food, the question remains, is it for you?

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Equipment, Food Preparation, Food Preservation, Safety around the home
7 Comments on Induction Cooking – What You Need to Know

Remember to Vent

Marlene Geiger 12 Comments

A critical step to achieving proper pressure inside a pressure canner is allowing it to VENT. What does this mean?

Venting is also “exhausting” the canner, a process of letting steam (and air) come out of the canner through the vent pipe for a period of time before beginning the pressure processing time.  Air trapped in a canner lowers the processing temperature and results in under processing of low-acid foods.  To be safe, the USDA recommends that all types of pressure canners must be vented 10 minutes before they are pressurized.

WHY VENT? 

It is STEAM, not water, that does the processing in a pressure canner. Low-acid foods (foods with a pH of 4.6 or higher such as all vegetables excluding tomatoes, meats, seafood, soups and sauces) are not acidic enough to destroy bacteria, their spores, and the toxins they produce or prevent the growth of botulinum bacteria in a vacuum.  The heat-resistant spores produced by C. botulinum can only be destroyed with the correct combination of temperature, pressure, and tested time. Temperatures in the range of 240°F to 250°F (115°C to 121°C) are needed to kill spores (USDA 2015). Water can get no hotter than the boiling point (212ºF, 100ºC), but steam can. Steam trapped in the canner increases the atmospheric pressure inside the canner causing the boiling point of water to increase to 240ºF-250ºF, the temperature needed to destroy bacteria and C. botulinum, that would otherwise be free to grow in a vacuum sealed jar.

In order to reach the optimum temperature to destroy botulinum bacteria, air inside the canner must be exhausted to allow space for a pure steam environment to build. There is a vast amount of air in a canner due to the space between the water level and the lid as well as the air that escapes from inside the jars and from the water. The most “jar air” comes from those with raw-packed foods.

Image Source: USDA Complete Guide to Home CAnning

HOW TO VENT

The vent or petcock is a short hollow pipe that sticks up above the canner lid.  When open, it allows air and steam to escape from the canner.  When closed, it holds steam inside. To vent a canner, leave the vent port uncovered or manually open the petcock (some older models).  After placing jars inside the warm canner and securing the canner lid, set the burner on high. Watch for steam to escape from the vent pipe. When a strong, visible, funnel-shaped steam cone emerges, set a timer for 10 minutes and let the canner continuously steam. After the 10 minutes, add the weight or counterweight to the vent or close the petcock to pressurize the canner.

WHAT HAPPENS DURING VENTING?

As the water boils inside the canner, the empty spaces become a mixture of steam and air. As steam increases, it pushes the air out creating a pure steam environment.  USDA processing times are based upon a pure steam environment which makes venting so very important.

In addition to venting, remember to adjust for altitude. Most recipes list processing time based on altitudes near sea level. To ensure the health of those who enjoy your foods, always use a tested recipe and follow instructions. Remember to VENT for 10 minutes to ensure that any and all microorganisms are destroyed.

Source: National Center for Home Food Preservation and USDA Complete Guide to Home Canning (2015)

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Equipment, Food Preservation, Food Safety
12 Comments on Remember to Vent

Meet Rachel Sweeney

Marlene Geiger

Rachel Sweeney is the newest member of the AnswerLine team!

Rachel giving a 4-H baking presentation.

AnswerLine is a new role for Rachel Sweeney, but Iowa State University Extension and Outreach is not. Rachel grew up on a diversified farm outside of Iowa City and was actively involved with Johnson County 4-H as a member of the Graham Champions 4-H Club. At an early age, she realized she could turn her interest in food and nutrition projects into a career, she decided to attend Iowa State University and major in that area graduating with bachelor’s and master’s degrees in dietetics and exercise science. After graduation, she spent a year in Nashville completing a dietetic internship at Vanderbilt University Medical Center.

Rachel’s began her professional career as an ISU Extension and Outreach human sciences specialist in Nutrition and Wellness, serving southeast Iowa for nearly seven years. In this role she led food preservation workshops, food safety trainings, and nutrition trainings for child care providers. After a brief stint as a retail dietitian, she returned to ISU Extension and Outreach as a program coordinator for Iowa 4-H Youth Development’s SWITCH (School Wellness Ingetration Targeting Child Health) program, an innovative school wellness initiative designed to support and enhance school wellness programming. After two years in this role, she got a new job title, MOM, in November of 2021, and a need to balance work and family life. AnswerLine provided the perfect opportunity for her to continue to work and enjoy her young family. One month into the job, Rachel says, “I have really enjoyed my first month on the job answering client’s questions and I look forward to continuing to learn and grow in this role to best serve the citizens of Iowa and Minnesota.”

When Rachel is not answering client questions via phone or email, she is likely with her family, 5-month old son, Thomas, and husband, Jim. She enjoys gardening, cooking and baking, food preservation, traveling, and being outside. As if she isn’t busy enough with work, family, and her many interests, she is also training for the swim portion of a half-Ironman relay-team competition in June! GO Rachel!!!!!

Rachel is a member of the Academy of Nutrition and Dietetics and stays involved with the Iowa Academy of Nutrition and Dietetics.

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Adult Learning, Child Development, Food Preservation, Food Safety, Recreation , ,
Leave a Comment on Meet Rachel Sweeney

Getting Ready for Canning Season

Marlene Geiger

Spring has arrived and it won’t be long before seeds or plants will find their way into the garden.  And that means that canning season is just around the corner so it’s time to get ready!  Having equipment ready and recipes selected before the fresh produce arrives helps to assure a successful canning season.

Recipes

Choose recipes that have been developed specifically for canning and come from research-based sources like the USDA Complete Guide to Canning (2015), the National Center for Home Food Preservation, So Easy to Preserve, or Extension resources from your land-grant university.  Recipes should be followed as written; canning is a science, not an art.  Therefore, alterations to the recipes should not be made. To learn more about the risks associated with modifying canning recipes with regards to swapping ingredients, adding ingredients, or increasing or decreasing ingredients, check out Modifying Canning Recipes by South Dakota State University Extension.  Penn State Extension also has an excellent article on Ingredients Used in Home Preservation, which describes ingredients and their function in canned goods.

Equipment

Safe canning methods include the boiling water bath method, the atmospheric steam canner method, and the pressure canner method. Each method uses a different type of canner. Electric, multi-cooker appliances should not be used for canning. Water bath and atmospheric steam canners require little maintenance and are used for canning high acid foods, pickles, fruit spreads, and most tomato products. (Atmospheric steam canners can be used in place of water bath canners as long as the canning process time is 45 minutes or less.)  Water bath canners have fitted lids and removable perforated or shaped-wire racks. The canner must be deep enough that at least 1 to 2 inches of briskly boiling water covers the tops of jars during processing.  All canners should be checked for signs of wear and corrosion on the body and lid. 

Pressure canners, used for low-acid foods (vegetables), some tomato products, and meats, require deeper inspection. Pressure canners have a weighted gauge, a dial gauge, or both for indicating and regulating the pressure. The lid gaskets along with the gauges, petcocks, vents, and safety valves should be inspected. Penn State Extension has a helpful inspection check list as a guide.  Pressure canners with dial gauges must be tested annually for accuracy. Gauges that read high cause under-processing and may result in unsafe food. Clostridium botulinum bacteria are the main reason why low-acid foods must be pressure canned to be safe. Home-canned foods are responsible for over 90% of all cases of food-borne botulism. Low readings cause over-processing. Your local extension office personal may have the equipment to test the accuracy of most dial-gauge canner brands such as Presto, National, Maid of Honor, and Magic Seal. National Presto Industries will also test gauges for free. (See University Minnesota Extension for more information.) All-American brand gauges cannot be tested at extension offices; contact the Wisconsin Aluminum Foundry, 920-682-8627 for help.* Burpee pressure canners can no longer be tested; the company is out of business and parts are no longer available for the Aristocrat; it is probably best to set these vintage canners aside as an heirloom or collectable. Dial gauges that are off more than two pounds of pressure should be sent to the manufacturer for repair or replacement. To learn more about canner gauge testing, watch Maintaining Your Canning Equipment by K-State Research and Extension. Iowa and Minnesota residents may call AnswerLine to find out where to go for testing.  Weighted or rocker-type pressure regulators do not require annual testing; the weights are not adjustable and usually maintain accuracy. 

It is also important to inventory canning jars, lids, and ring bands. Mason-type jars specifically designed to withstand the heat necessary for home canning should be used. Check jars for rim nicks, blemishes and hairline scratches or cracks.  Jars exhibiting any issues should not be used for canning; instead they can be recycled for dry food or pantry storage. Jar size plays a role in process time so the jar size called for in the recipe must be used. Two-piece lids are needed to seal the jars; the flat lid can only be used once while the ring band may be re-used unless it is rusty or dented.  For best results, use recently manufactured flat lids from reputable manufacturers.

Other essential canning equipment to locate and check for safe use include funnel(s) for large- and narrow-mouth jars, jar lifter, racks, food mill, jelly bags, bubble popper tool, and headspace gauge.  Make sure that everyday kitchen items like tongs, ladles, strainers, colanders, cheese cloth, long handled spoons, and a slotted spoon are conveniently located.  Also be aware that some canners cannot be used on glass stovetops and that a newly acquired electric range (since 2019) with coil burners may not allow consistent heat due UL858(60A) standards.[1].  A portable burner may be a suitable option provided NCHFP guidelines are considered.

Canning your own garden produce or farmer’s market produce can be rewarding and a great way to save your food for later use. Be ready by planning and preparing now.

*Newer models of the All American canner have both regulator weights (weighted gauge and dial gauge). [Picture 1.]  If the weight begins to rock at the desired pressure and the gauge is off by more than 2 psi the company recommends replacing the gauge. The gauge is now used as a reference to know when the unit is at 0 psi and can safely be removed.  The petcock on older All American Canners [Picture 2] can be replaced with a weighted gauge. Contact Wisconsin Aluminum Foundry for more information.  Photos used with permission from K-State Research and Extension.

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Consumer Management, Food Preservation ,
Leave a Comment on Getting Ready for Canning Season

Freezing Yeast Dough

Marlene Geiger 4 Comments

The frozen yeast dough products available at the supermarket are a nice convenience.  But, did you know that yeast dough can also be prepared at home and frozen to nearly duplicate the convenience of a ready-to-use product?

Fleishmann’s Yeast introduced home bakers to freezing yeast dough in their 1972 publication, Fleishmann’s Bake-it-easy Yeast Book.  Included in the book were the very first recipes for frozen dough one could make at home, freeze, and bake later.  The recipes introduced were specifically developed for freezing and to this day, they remain the standards for freezing yeast doughs.

It should be noted that freezing dough at home may not yield the same results as commercially frozen dough but is still a means to delicious, freshly baked bread when time is short. Frozen dough manufacturers have access to superior dough stabilizers and freezing equipment that freeze the dough very quickly, allowing doughs to freeze with minimal damage to the yeast and dough structure. Dough freezes slower in home freezers increasing the risk of damage to the yeast and dough structure.

Tips for Preparing Yeast Dough for the Freezer  

  • According to Fleishmann’s Yeast, only yeast dough recipes specially developed for freezing should be used for best results. Freezer dough recipes usually call for more yeast and sugar and less salt and fat. The most success is achieved with roll or pizza dough.  The method of preparation is not limited; dough can be made by hand mixing and kneading, mixer, food processor, or bread machine.
  • Original freezer-dough recipes used all-purpose flour.  Today, it is recommended to replace all-purpose flour with bread flour as it helps to maintain better structure.   
  • Active dry yeast should be used instead of fast-acting yeast. Fast-acting yeast is not ideal for recipes that require a long rising time.  King Arthur Baking suggests making the dough with cool, not lukewarm liquid (water or milk) to keep the yeast as dormant as possible so that it is less vulnerable to damage during the freezing process.
  • To compensate for the yeast that will inevitably die in the freezing process, King Arthur Baking suggests increasing the yeast by ¼ to ½ teaspoon per 3 cups (360 grams) of flour.
  • Dough may be frozen at two junctures: 1) after kneading and before the first rise (proofing) OR 2) after the first or second rise.  American Test Kitchen tested both junctures and found “freezing the dough between the first and second proofs was the best strategy. The first proof ensured that enough yeast had fermented for the dough to develop complex flavors and for some gluten development for better baked size. The remaining viable yeast cells then finished the job as the dough thawed and proofed for the second time.” 
  • Form the dough into balls for rolls or flatten the dough into a disk about 1 inch thick for pizza crust or dough to be shaped later. French bread, loaves of bread, braids, and cinnamon rolls can be shaped prior to freezing; loaves should be frozen in greased loaf pans and cinnamon roll slices placed on their sides on a lined baking sheet. Tightly wrap the dough with plastic wrap.
  • Flash freeze the dough in the freezer for 1-2 hours. Dough should be covered during flash freezing, thawing, and rising prior to baking to prevent the dough from developing a dry crust.
  • When the dough pieces have formed a hard shell around the outside, transfer to a zipper freezer bag or air-tight freezer container.  Return the dough to the freezer.  Dough may be frozen up to 1 month. For best results, use dough sooner rather than later.

When ready to use, remove needed dough balls, loaves, rolls, or disks from the freezer and allow to thaw covered in the refrigerator, a warm location, or combination until doubled in size. Do not over proof.  Since the yeast and bread structure have been compromised during freezing, over proofing may cause the dough to collapse on itself.

Previously formed dough can be thawed in a greased baking pan until double. Disks should be allowed to thaw and then rolled or shaped (pizza crust or any shape or specialty desired), placed in a greased baking dish, and allowed to rise until doubled. (Rolled dough for pizza crust does not need time to double unless desired.)  When dough has reached the desired size, bake as directed.

Thawing and rising times vary according to the temperature of the dough, the size of the dough pieces, and where thawing takes place.  Use these times as a guideline for thawing [1]:
Refrigerator: 8-16 hours
Countertop:  4-9 hours
Warm location:  2-4 hours
Dough balls for dinner rolls take about 1½ -2 hours to thaw and double before baking in a warm location.  Loaves of bread may take 4-6 hours at room temperature.

Recipes for freezer dough can be found on the Fleishmann’s website. Some examples include: pizza dough, bread dough, and dinner rolls.   If one is so lucky to have a copy of Fleishmann’s Bake-it-easy Yeast Book, 1972, a variety of yeast doughs developed for freezing can be found therein.

Fresh-baked bread is always more delicious than reheated. If you plan ahead, you can freeze yeast dough to save time provided you remember to pull it from the freezer in time—that’s the hardest part! 


_________________________________
References: 

Almost Pop ‘n’ Serve Dough, Cook’s Illustrated. https://www.cooksillustrated.com/how_tos/6065-almost-pop-n-serve-dough

Can Dough Be Stored in the Refrigerator or Freezer?, Fleishmann’s Yeast. https://www.fleischmannsyeast.com/frequently-asked-questions/

Fleishmann’s Bake-it-easy Yeast Book, 4/1972.

Fleishmann’s Yeast Best-Ever Breads, Specialty Brands, 1993

Hamel, PJ. (2015, October 5). Freeze and Bake Rolls. King Arthur Baking Company®. https://www.kingarthurbaking.com/blog/2015/10/05/freeze-bake-rolls?fbclid=IwAR0jISWL4_1eJ2NQGIcbzuuEQCWdLM-T-1RbVw6STyJidhNYJStLeAK2tSI&utm_source=facebook&utm_medium=social&utm_campaign=content&sf172188106=1

Kneaded Notes:  Holiday Baking Guide, Red Star® Yeast. https://redstaryeast.com/blog/holiday-baking-guide/

Nicholson, Annabelle. (2021, July 6). Can I Freeze My Yeast Dough?, King Arthur Baking Company®. https://www.kingarthurbaking.com/blog/2021/07/06/freeze-yeast-dough-make-ahead-bread

Woodward, Peggy. (2020, May 7). How to Freeze Yeast Dough. Taste of Home. https://www.tasteofhome.com/article/freezing-yeast-dough/

Reference to any commercial product, process, or service, or the use of any trade, firm, or corporate name is for general informational purposes only and does not constitute an endorsement, recommendation, or certification of any kind. Persons using such products assume responsibility for their use and should make their own assessment of the information and whether it is suitable for their intended use in accordance with current directions of the manufacturer.

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Food Preparation, Food Preservation ,
4 Comments on Freezing Yeast Dough

Are Two-Piece Lids Really Necessary?

Marlene Geiger

The pandemic of 2020 brought big frustrations for home canners as they searched and scrambled for two-piece lids. Out of frustration and desperation to get garden produce into jars, canners turned to using lids from uncertain suppliers, one-piece lids, reusable lids, and sadly reusing lids from previously canned foods (definitely a NO! NO!). 

The USDA and the National Center for Home Food Preservation (NCHFP) recommend and support the two-piece lid system even though one-piece and reusable lids are available.  Why two-piece lids for canning?  

The two-piece lid system (flats and screw bands) is still the best option for home canners. They are easy to use, known to seal reliably, and easy to tell if the jars sealed. When researched guidelines are followed by users, the two-piece lid system safely replaces the vacuum system used for commercially canned foods with a self-sealing system consisting of a flat metal lid held in place by a metal screw band. A trough around the outer edge of the flat lid holds a rubber-like, plastisol sealing compound which acts like a gasket; heat causes the compound to flow slightly over the rim of the jar.  During processing, the gasket allows air to escape from the jar and then forms an airtight seal as the jar cools. 

To ensure safe home canned foods, follow these important tips for two-piece lids:

  • Use new lids (flats) each time; after the first use the lid will no longer seal effectively. With careful handling, canning jars and screw bands may be reused many times. 
  • Purchase your lids (flats) from reputable suppliers.
  • Buy only the quantity of lids (flats) that will be used in a year’s time—please don’t hoard.
  • Follow the manufacturer’s directions for preparing lids (flats) to make sure to get a good seal. Heating of most flats is no longer needed or recommended by manufacturers. In fact, heating may actually cause lid failure.
  • Carefully observe headspace requirements for the product.
  • Removed air bubbles inside the jar with a plastic or silicone spatula.
  • Make sure the rim of the jar is clean before placing the flat lid on the jar.
  • Tighten the screw band as specified by the manufacturer.  Usually this is fingertip tight, which means the first full resistance is felt using just your fingertips.
  • Check all metal lids carefully. Don’t use old (more than 5 years old), dented, deformed, or defective lids.
  • Do not re-use lids from previously canned foods.

One-piece, reusable, and previous used lids are not approved for home canning by the USDA as they may allow air to be trapped within the sealed jar permitting bacteria to thrive and spoilage to occur which can lead to illness and even death.   While one-piece lids are available for home canning, they were made for use in industry where very strict time and temperature controls are in place.  Because they do not allow air to escape properly in home canning, consumers have reported jar breakage and lids buckling.

Reusable canning lids have been around for decades [1]. Research conducted through the National Center for Home Food Preservation on the reusable lids revealed that the three types of reusable lids they tested had an acceptable seal and removed the necessary amount of air. However, despite these finding, it was still recommended that the traditional two-piece metal lid system be used to “ensure the highest confidence in sealing.” [1] While there is no data to indicate that these lids will not perform satisfactorily if the manufacturer’s instructions are followed explicitly, the USDA and NCHFP cannot recommend their use due to a lack of researched-based information about their performance.

Lastly, recommendations and recipes from the USDA and NCHFP are currently based on the two-piece metal lid system.  The recommendation does not come lightly; it is backed by a body of research documenting how well they work consistently for safe home canning.

Why take a chance?  TWO-PIECE LIDS REALLY ARE NECESSARY. 

________________________________________

Sources: 

1G. Sivanandam. Evaluation and Comparison of the Sealing Performance of Three Major Types of Jar Lids Available for Home Canning. Thesis Project – University of Georgia. https://tinyurl.com/pj7ywjat

National Center for Home Food Preservation (NCHFP), Recommended Jars and Lids, https://nchfp.uga.edu/how/general/recomm_jars_lids.html

North Central Food Safety Extension Network, North Dakota State University, Put a Lid on It, Best Practices for Using Closures for Home-based Canning, https://www.ncrfsma.org/files/page/files/fn2028_put_a_lid_on_it_fillable_information.pdf

University of Missouri Extension, GH1452, Steps for Successful Home Canning, https://extension.missouri.edu/publications/gh1452

University of Wisconsin-Madison Extension, Put a lid on It, Best Practices for Using Closures for Home-Based Canning, https://fyi.extension.wisc.edu/safefood/files/2021/04/Closures_2021.pdf

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Equipment, Food Preservation, Food Safety
Leave a Comment on Are Two-Piece Lids Really Necessary?

Getting to Know the National Center for Home Food Preservation

Marlene Geiger 1 Comment

When AnswerLine clients have questions about food preservation, reference is often made to the National Center for Home Food Preservation (NCHFP).  What is the National Center for Home Food Preservation?  What relationship does it have with the United States Department of Agriculture (USDA) when it comes to food preservation?

National Center for Home Food Preservation Banner used with permission from NCHFP.

The National Center for Home Food Preservation (Centro Nacional para la Conservación Doméstica de Alimentos) is a publicly-funded center for research and education for home food preservation. The center is located in Athens, Georgia at the University of Georgia® and hosted by the College of Family and Consumer Sciences. The NCHFP is your source for current research-based recommendations for most methods of home food preservation.  The mission of NCHFP is to conduct and coordinate research to further develop knowledge in the field of food preservation and to share science-based recipes, techniques, and guidelines with educators and end-users to insure that foods preserved in the home are done so safely.

The Center was established in 2000 with funding from the National Institute of Food and Agriculture, U.S. Department of Agriculture (NIFA-USDA) to address food safety concerns for those who practice and teach home food preservation and processing methods. The Cooperative Extension System (CES) and USDA have long been recognized as credible sources for science-based recommendations. For more background on the USDA work in food preservation and the founding of the NCHFP, see the webinar, Welcome to the National Center for Home Food Preservation.

Dr. Elizabeth Andress, who was instrumental in founding NCHFP, became the first director in 1999. She served as director until her retirement in December 2021.   During her tenure, the center researched home canning and preservation recipes and methods; published So Easy to Preserve; developed the NCHFP website; wrote current topic blogs; developed preservation curriculum and courses suitable for institutions, workshops or webinars; and revised and updated the USDA Complete Guide to Home Canning (2015).  The NCHFP webinar also discusses additional work done by the center.

NCHFP is now under new leadership.  In November 2021, the University of Georgia announced Dr. Carla Schwan as the new director of the NCHFP along with titles of Assistant Professor and Extension Specialist in food safety and home food preservation. Dr. Schwan recently completed her PhD and postdoctoral research at Kansas State University and began her appointment at NCHFP January 2, 2022. NCHFP has been a strong resource for home food preservation research and guidance and will continue to be there for consumers under Dr Schwan’s leadership.

The resources provided by the NCHFP have become increasingly important in recent years.  Due to consumer desire to have more control over their food and the impact of COVID-19, many consumers have turned to home gardening and food preservation at home.  Both factors have led to demand for science-based information to educate consumers on safe methods to preserve food. 

Every consumer interested in food preservation should faithfully use the resources provided by NCHFP.  If you are not familiar with the NCHFP, spend some time perusing the website or order So Easy to Preserve or USDA Complete Guide to Home Canning (2015).  You’ll discover useful food preservation tips, find answers to food preservation questions, and be inspired to can, freeze, dry, pickle, jam and jelly at home safely!

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

More Posts

Consumer Management, Food Preservation
1 Comment on Getting to Know the National Center for Home Food Preservation

AnswerLine

Connect with us!

AnswerLine's Facebook page AnswerLine's Pinterest page
Email: answer@iastate.edu
Phone: (Monday-Friday, 9 am-noon; 1-4 pm)
1-800-262-3804 (in Iowa)
1-800-854-1678 (in Minnesota)

Archives

Categories

Meta