Category Archives: Food Quality

Time to Get Blueberries in Your Freezer?

Fresh blueberries laid out in single layer on a tray

 

Fresh blueberries are in abundant supply in many states now.  Blueberries are easy to freeze and maintain great quality for year-round use in favorites such as muffins, pancakes, and smoothies.  They are nutrient dense and add freshness and flavor to meals.

Blueberries can be prepared for freezing using two methods.  Dry pack and crushed or puŕeed. If you can’t freeze right after picking, refrigerate at 40 degrees F or below until ready to prepare and freeze. Work with small batches to prevent loss of nutrients and quality.

Dry pack is the easiest method.  Most advice says do not wash the blueberries; the skins will toughen if frozen wet. (If you do want to rinse them off with clean water, be sure to completely dry again before packaging and freezing.) Remove leaves, stems, and any bruised or immature berries. Package berries into moisture vapor resistant packaging, either rigid plastic or flexible bags.  Leave headspace.

Tray freezing before dry packaging allows blueberries to remain loose; and easier to remove in smaller amounts.  Spread a single layer of berries on shallow trays and freeze.  Once frozen, remove and promptly package.  Return to the freezer immediately.  When ready to use, remove from packaging and wash blueberries thoroughly by gently rubbing under cold running water.

Crushed or puréed is another method for freezing blueberries.  To prepare for freezing, remove leaves, stems, and any bruised or immature berries.  Wash blueberries thoroughly by gently rubbing under cold running water. Drain in a colander and blot dry with paper towels.

Crush, press through a fine sieve, or process in a food processor or blender. Mix with 1 to 1-1/8 cups sugar with each quart (2 pounds) of crushed berries or purée.  Stir until sugar is dissolved.  Package in freezer containers, leaving headspace.  Label, seal, and freeze promptly.   Keep an accurate inventory of the freezer.  Use first in, first out method to use blueberries at peak quality.

If you plan on using your frozen berries at a later time to make jam or jelly, freeze them unsweetened or follow the proportions of sugar to berries in the jam recipe you will eventually use.

Taking time to freeze fresh blueberries with care will provide delicious, high quality, and nutritious fruit for use year-round.

(The links on this page can be found at https://nchfp.uga.edu)

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Dry grains and beans in canning jars

“Dry Canning” Isn’t Canning To Me

Quite a few people are circulating directions for what they call “dry canning” as a method of storing dried foods. It is not a food preservation method we recommend.

What is canning?

Just because canning jars are used in “dry canning” does not mean the suggested procedures fit the classic definition of canning.

Canning as a method of food preservation or processing refers to a procedure of heat treating closed containers of food with the goal of producing what is called a “commercially sterile”, vacuum sealed-food that can then be stored safely at room temperature. The preservation goal is to kill any spoilage and pathogenic (harmful) microorganisms that otherwise would be able to survive in food at room temperature storage. In some categories of foods, bacteria can also be controlled by acidity or moisture control as well as the heat of canning. In other foods (e.g., low-acid or slightly acid foods) heat usually has to do the whole job. Different foods will have different microorganisms targeted for killing or control, depending on the nature of the food.

Why dry canning isn’t canning

Canning is done with moist foods because the moisture inside the container would support the growth of microorganisms. Dried foods do not have the same concerns even if a food is low-acid because the removal of available moisture limits or prevents the growth of microorganisms. Storage of dried foods for long periods of time will take into consideration means to preserve food quality, however, as well as preventing reabsorption of moisture into the food.

“Dry canning” techniques I see circulating call for putting dried food like grains, beans, and nuts, into canning jars. In some methods, canning lids are then placed on the jars and the jars heated in an oven. Usually about 200°F is recommended. In other directions, the food in jars is heated without the lids, which are then placed on the jars when they come out of the oven.

These procedures do not describe true canning preservation of food but instead would be considered a method of packaging dried foods for storage — one that, again, we cannot recommend because of several issues with it.

Issues with dry canning

Here are some issues to think about with this concept:

  1. This process is not “canning” just because it uses canning jars.
  2. It is unknown if this process can sterilize the food, although it might cause vacuum sealing of jars. This would not be a time and temperature combination known to kill many bacterial spores or mold spores.
  3. This method does not remove all of the oxygen from the jar before sealing and may trap moisture from the food if condensation occurs. While the presence of spores would not be an issue in very dry foods, any moisture pockets say from condensation or incompletely dried foods could be a problem. Moisture in the jar with some retained oxygen could support the growth of airborne molds or even bacteria not killed by the low heating in some seemingly dry foods. Some foods may seem dry to the consumer but still have enough moisture in them to come out upon heating and closing up in a container. This could be especially true of home dried foods.
  4. The dry oven process used at home has never been shown to sterilize these various dry foods or produce the claimed extended shelf life with quality. In fact, there is no known researched shelf life for foods packaged just this way at home.  (If someone can lead me to the research I have not been able to find, please let me know.) Extended shelf life expectations are available for dry foods prepared and packaged by other methods (see the Utah State University Extension references below).
  5. This heating could even make the quality of some foods worse.  This could be either by moisture condensation upon cooling, or if the food is lipid-containing nuts and grains, increased enzymatic reaction causing rancidity.
  6. A major manufacturer of canning jars and lids in the U.S. does not support the use of their jars and lids/sealing compound in this manner.
  7. Because this type of process is not recommended, doing it can be a waste of resources, time and energy.

Recommended storage methods for dry goods

dry_bean_light

Photo by E. Andress

 

Thoroughly dried foods can be stored a fairly long time in airtight containers at moderate room temperatures or in the freezer. If you want to vacuum seal containers of dry foods, methods that will preserve them safely and provide better food quality include:

(1) A vacuum sealing machine that has adapters for jars in addition to sealing bags if you want your food in jars.  This vacuum packaging is done at room temperature without heating the food.

(2) Oxygen absorbers inside your containers of these foods.  Oxygen absorbers can help preserve the quality of foods and also aid in insect control.

(3) If you are using the heating method to control for possible insect contamination of your dried food, the Utah State University booklet linked below has methods for heating and then cooling dry foods BEFORE they are packaged for storage. It also describes freezing procedures before packaging as an alternative to insect control. Even heating some foods on an open oven tray before packaging can cause some flavor changes that using the freezing method would not.

Utah State University Extension methods, for example, for long-term storage of dry rice and beans:

10-year storage of rice: https://extension.usu.edu/foodstorage/howdoi/white_rice

10 or more years for beans:  https://extension.usu.edu/foodstorage/howdoi/dry_beans

And here is a large book/booklet from Utah State University about storing food, A Guide to Food Storage for Emergencies, with more specific information and the oven or freezing methods for insect control:

https://extension.usu.edu/foodstorage/ou-files/Food_Storage_Booklet2.pdf

I would like to thank my colleagues in some other states for helping to review and contribute to these points. Nancy Flores at New Mexico State University helped get some organization and formatting to them, and Karen Blakeslee at Kansas State University helped with review and additions.  There were others who initially reviewed my first version and I thank them also.

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Orange Marmalade to Brighten Your Day

Sometimes new is better than the tried and true older version of something.

We took a look at the long-standing original Orange Marmalade procedure in the University of Georgia’s So Easy to Preserve book and decided to make it easier (and better?). The book version has a 12 to 18 hour standing period of the fruit and water ingredients before continuing with adding sugar and cooking. We found this wait to be unnecessary in affecting the outcome of the final product so we were able to shorten the procedure. Also, the book directions have you measure the fruit and water volume in cups after this standing period and then calculate the amount of sugar to add. That was a bit messy (and dirtied more dishes to wash!), so after some repetitions to figure out a specific amount of sugar to use with each batch, we eliminated that step, too!

Of course this will not get changed in the book until there is a new edition (a totally unknown date at this time, by the way) but our National Center for Home Food Preservation website makes it possible to bring it to you right away. The recipe is posted here: http://nchfp.uga.edu/how/can_07/orange_marmalade.html. We used navel oranges in our recipe development, and left all of the white albedo attached. See notes at the bottom of the recipe page.

This is still a traditionally very sweet marmalade that gels from correct cooking with the right proportions of sugar and pectin as well as acid. It is partially preserved for the recommended short canning procedure by the sugar content as well as acidic fruit, also. We recommend cutting the orange peel into very thin strips; it is “chock-full” of orange peel. However, the sweetness makes it not too bitter. (I will admit, I have never been a marmalade fan, but I do really like this one!)

The pectin comes from the citrus fruit albedo (the white pith or tissue right under the outer peel) that is included. As with all cooked jams, jellies or marmalades that gel without added purchased pectin, but only with the pectin found in the fruit, cooking to the right temperature for gelling will be a little variable depending on your actual fruit and pectin content, speed of boiling and size of cooking pot. Our yield is usually just the 7 half-pint jars or in one batch, at least another partial jar. It is important not to overcook, also, or you pass the point where the pectin will gel.

Brush up on your measurement of determining “doneness” if you need to! Temperature might work well with this one, or get a small glass plate cold in the freezer while you cook. When you are ready to test for doneness, take the plate out and drop a few drops of the marmalade onto the cold surface. It should hold its shape pretty well. If you use the Spoon Test, be sure you are capturing the jelly part of the marmalade on your spoon and not fruit or peel. You have to work  quickly with all these, and take the pan off your burner. You don’t want to overcook, either, and get a marmalade that is too stiff or gummy. This stage makes these methods a little less precise than cooking jams or marmalades with added pectin, but also makes them more special as you work to perfect your product!

If marmalade is something that can help brighten your morning or other meals with a little addition of flavor and color, enjoy!

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Celebrate Eating Together

On December 3, Family & Consumer Sciences Day is being celebrated with a “Dine In” theme. Since 2014, more than 300,000 people have publicly committed to dining in on the annual Family & Consumer Sciences Day http://www.aafcs.org/fcsday/home). This day also celebrates the birthday of Ellen Swallow Richards, the founder of what is now the American Association of Family and Consumer Sciences (AAFCS), formerly called the American Home Economics Association. The website above lists over 30 different valued sponsors or partners in this initiative. The promotion is an international event.

People are being encouraged to make a commitment to preparing and eating healthy meals with their family or others in their community. This is a fitting tribute to Ellen Richards, as she so believed in people working together and valuing family and community. You might consider this a good day to get some home prepared and preserved foods out of your freezer or pantry and share them together in a setting of community eating, whether with our own family or a group you invite to eat home prepared foods together. Maybe your community garden groups would like to share a meal of local foods and talk about community and health!

For other ideas, you can monitor the entries communities are sharing at http://www.aafcs.org/fcsday/home, or on Twitter and Facebook. Resources, such as an original recipe from the Beekman Boys cookbook and recipes certified by the American Heart Association can be found here: http://www.aafcs.org/fcsday/fcs-day-resources/dining-in-resources and http://www.aafcs.org/fcsday/fcs-day-resources/fcs-day-web-resources. Links to food preparation videos from The Art Institutes as well as Texas A&M University, food-related resources to use with children, and many other resources are also provided links. And of course, even if you do not want to can them, you can find interesting recipes at the National Center for Home Food Preservation for some relishes, fruit dishes, and salsas for your sides! (http://nchfp.uga.edu)

You can read a little more about Ellen Swallow Richards here, http://connect.aafcs.org/about/about-us, as well as in many other sources. Ellen Richards, a chemist, was the first female graduate and professor at the Massachusetts Institute of Technology. Smith College conferred an honorary degree of Doctor of Science on her. She was an activist for nutrition, foods education, child protection, public health, women’s rights, and the application of scientific principles to everyday living for the family. Her activism, vision and professional experiences led to formalization of the home economics profession and founding of the American Home Economics Association. Here is one short biography: https://libraries.mit.edu/archives/exhibits/esr/esr-biography.html. I have done a lot of archival research and reading myself about Ellen Richards’ life and professional contributions, especially regarding public health and safe food and water. It is nothing but inspiring, especially when you read a lot of her correspondence with other foods and nutrition professional leaders in the late 1800s.

(References are the links provided above throughout the text.)