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Posts Tagged: Master Food Preserver

Keep spoilage away with UC Master Food Preserver guidelines

Mark lids once they are used to easily keep them separate from new lids. (Photo: UC Master Food Preserver Program)
What's the best aspect of food preservation in the winter? Safely enjoying the fruits (veggies and meats) of your labor! How do you ensure that time is spent savoring the sight, smell, and taste of a home preserved product, rather than turning up your nose at unsightly mold speckled contents?  

First, stay organized.

From the very beginning, implement a canning system. For example, jars, lids, and rings are used in the canning process, but not all can be re-used. Visibly mark used lids to denote they are out of commission for the next round of canning. This will prevent unnecessary seal failures.

Second, rotate the pantry.

To ensure the nutritive value of the food you have preserved, use products within a year of being canned. A quick way to track this is by making labels with tape and a marker or blank stickers; this is a simple approach you can take to enjoy home-canned products at their best quality. Keep inventory of what products were used, liked and disliked. Use this information to plan for next season's canning escapades.

An example of hand-labeled products with date and product-type. (Photo: Missy Gable)

Pro tip: Store jars with rings removed to allow for easier detection of seal failure. When removing the ring, wash, rinse, and dry to combat mold growth and corrosion.

Jars are cleaned, dried and rings removed prior to storage. (Photo: UC Master Food Preserver Program)

Finally, avoid spoilage.

Prevention is key because once spoilage has contaminated a product, it cannot be salvaged. Using the proper amount of headspace when canning allows for a good seal in a low oxygen environment. If too much headspace is left, there may be excess oxygen that was not driven from the jar during processing. If the headspace is too little, the product may siphon out of the jar, get deposited on the rim, and prevent a clean seal.

Given a few key elements, mold can develop. Discard canned products with any sign of mold. (Photo: UC Master Food Preserver Program)
If there is mold growth in your jar, don't eat any of the contents. It might be tempting to scrape away the mold and eat the rest. However, mold growth in foods can actually alter the pH of the product. Interestingly, a jar that contained high acid products could become a low-acid food due to mold growth and be at risk for botulism. Some mycotoxins (toxins produced by molds) can cause illness or are carcinogenic. When in doubt, throw it out.

While molds can come in many different colors, not every type of discoloration found in a home-canned food is indicative of spoilage organisms. Sometimes, the undersides of the metal lid discolors. No need to panic if the product was properly processed and sealed. According to the University of Georgia, So Easy to Preserve, “natural compounds in some foods, particularly acids, corrode metal and make a dark deposit on the underside of jar lids.”

If you'd like to learn more about ways to enjoy home-canned goods and avoid spoilage, the UC Master Food Preserver Program has volunteers that are a wealth of information. Find a program near you to attend public classes on home food preservation or go through a training program.

Posted on Tuesday, January 30, 2018 at 2:53 PM
Focus Area Tags: Food

Building blocks of health

The scenario: Tomorrow is farmers market day, but not just any market on any day. This market happens once a month as part of a collaboration between the Food Bank Coalition of San Luis Obispo County and Lopez High School. The high school, a continuation school in the south part of San Luis Obispo County, has a program called Hands-On Parenting Education, or HOPE, which helps expecting and parenting teenagers to graduate.

It's the day prior to market day and HOPE students have a guest lecturer today: Dayna Ravalin, UCCE Master Food Preserver coordinator of San Luis Obispo/Santa Barbara counties. She's demonstrating how to make and store baby food safely. The timing is impeccable as students can (and do, as a result of the lesson) load up on fresh ingredients the very next day.

Dayna takes the students through the Core Four food safety tips while demonstrating how to convert fresh market produce into baby food blocks.

  1. Clean - Wash hands with warm water and soap for at least 20 seconds before and after handling food. Wash cutting boards, utensils, and counter tops with hot soapy water after preparing each food item and before you go on to the next food.
  2. Separate - Don't cross contaminate. Keep raw meat and poultry apart from foods that won't be cooked.
  3. Cook - Cook to safe temperature.
  4. Chill - Chill leftovers and takeout foods within 2 hours. Keep fridge at 40°F or below.

Lastly, students are shown how to easily preserve that baby food to last through the month or longer, until the next Lopez High School/Food Bank Coalition market day. Ravalin demonstrates the use of an ice-cube tray to aide in freezing baby-sized portions before providing each student with their own tray to take home, empowering them with building blocks for healthy eating.

The students leave, eager to take advantage of their resources the next day, and with two basic recipes using seasonal produce to get them started.

Homemade Baby Food Recipes


-      1 pound of carrots
-      1 cup water

Trim and peel carrots, cut into 1-inch segments. Put in a medium saucepan with the water. Bring to boil, reduce to a simmer, cover the pot and cook for 25 minutes (this will take longer if your carrots are thicker). Let cool in cooking liquid. Purée in a food processor, blender or food mill, cover and freeze in small portions.
Add in ideas: pinch of cumin, coriander, cinnamon or mashed potatoes.


-      2 sweet eating apples or pears
-      4 to 5 tbsp. water or pure apple juice

Peel, halve, core and chop the apples. Put into a medium saucepan with the water or apple juice. Cover and cook over low heat for 6 to 8 minutes until really tender. Let cool in cooking liquid. Puree in a food processor, blender or food mill, cover and freeze in small portions.
Add in ideas: pinch of cinnamon, pureed carrots, ginger

Cubes of baby food made from applesauce, potato puree, spinach puree, carrot puree, and pear puree. (Photo: Dayna Ravalin)

“You can even freeze the different purees in layers so it is triple colored when you empty the trays,” Ravalin said.

Through this 1.5 hour lesson, the expecting and new parents learned how easy it can be to extend the life of food, taking advantage of the school's monthly market to provide for their families. This partnership is one example of how UC Master Food Preserver Program volunteers donate more than 20,000 hours of their time annually educating families throughout California on safe food preservation.

Posted on Monday, March 27, 2017 at 7:23 AM

The well-rounded pumpkin: A versatile vegetable

UC Master Food Preservers volunteers can instruct on safe preservation techniques for pumpkin flesh. (Photo: Pixabay)
From seed to table or as seeds on the table, there are many edible forms of this staple fall decoration. While some ease their teeth into the lightly cooked tender green shoots of the plant, the majority of people know the pumpkin in its spherical orange form, with a few teeth missing. But what is the life of a pumpkin outside of an embellishment to autumn and Halloween décor?

In addition to those grown for use as jack-o-lanterns, varieties such as Sugar Pie and Fairytale work well in the kitchen. 

The seeds                                                                                  

Seeds become crunchy snacks when dried and roasted. For both techniques, thoroughly remove the stringy bits of flesh that cling to the outer layer of the seed. Dry at 115⁰-120⁰F for 1 to 2 hours in a home dehydrator or in a warm oven for 3 to 4 hours; alternatively, seeds can be dried in the sun. Rotate seeds regularly to promote even drying and avoid scorching. Dried seeds can then be roasted in a 250⁰F oven with a light spritz of oil and salt for 10 to 15 minutes.

The flesh

Wash the exterior of the pumpkin and remove the seeds and accompanying fibrous strands. The flesh can be skinned and cubed into 1-inch pieces as a starting point. Some home preservation options include:

  • Pressure canning – in CUBES only. Do not mash or puree. Put that food processor away; keep botulism at bay.

Note that contents can be mashed when removing the jar from the pantry for use in such foods as pumpkin butter, ice cream, and pie all year round.

  • Drying –
    • in 1/8-inch thick pieces for a chewy snack.
    • make a leather: cook and puree flesh with honey, cinnamon, nutmeg and cloves. This is an appropriate and safe use of that food processor.

  • Freeze – cook, mash, cool and freeze for future use.
The seeds can be dried, roasted, or even saved to plant next year. (Photo: Unsplash)

Want to learn more about the details of these processes? Take a UC Master Food Preserver class or ask a UC Master Food Preserver volunteer. Many programs are accepting applicants for upcoming trainings.  The UC Master Food Preserver Program is open to individuals looking to increase community knowledge in home food preservation methods. Applicants for the UC Master Food Preserver Program must be willing to share knowledge and skills learned from the certification training through local community outreach. Prior food preservation knowledge is not a requirement; willingness to teach others is.

Come full circle by saving seeds for next year's garden. Keep seeds and preserved pumpkin products in a cool, dry place until ready to use. Plant seeds in June for an October harvest and go easy on the water – pumpkins make the list of water wise vegetables, according to the UC Master Gardener Program of Marin County. The Pumpkin Production in California publication notes, “Excessive irrigation aggravates root and stem rot problems and increases humidity in the lower canopy, which contributes to foliage and fruit disease.”

If time cannot be carved out for pumpkin preserving this year, the UC Davis Arboretum offers a Carve ‘n Compost workshop later this month. With all these options, be sure to enjoy this October's harvest in one of its many forms.

This story en español. 

Pumpkins come in many shapes, sizes, and colors and are used to decorate or consume. (Photo: Katelyn Ogburn)
Posted on Tuesday, October 11, 2016 at 8:23 PM

Looking back at your leftovers

A Thanksgiving meal can leave lots of leftovers. recommends a labeling system for food storage.
It's that time of year again when refrigerator space at most homes is like prime real estate. Thanksgiving leftovers abound and December treats await creation.

In order to keep the holidays from being spoiled, here are a few tips and tools to have at your disposal. First, check out the food storage chart to know the storage times for your food goodies. For example, cooked poultry has a shelf life of 3 to 4 days in the refrigerator, but can be extended to 2 to 6 months in the freezer. When reheating leftovers in the microwave, remember to bring them to a temperature of 165 degrees F.

If you struggle to remember how old your leftovers are, you are not alone. While lifespan varies, generally there is a four-day guideline. You can use an easy labeling system or even search for food storage phone apps to aid your memory. Iowa State University Extension mentions the 4 Day Throw away app as one possibility.

If both refrigerator and freezer space is now completely taken, but you still want to make some holiday gifts, consider dehydrating, pickling, and canning. Some fall/holiday ideas include:

  1. Dehydrated fruits – colorful, healthy and space saving
  2. Pie filling – a perfect gift for busy friends or family
  3. Fall Garden Relish (recipe below from So Easy to Preserve, sixth edition)
  4. Lemon curd – sweet, sour, rich, and buttery all at once. Yum!


Fall Garden Relish
Recipe from the National Center for Home Food Preservation
(Yields about four pint jars.)

1 quart chopped cabbage (about 1 small head)
3 cups chopped cauliflower (about 1 medium head)
2 cups chopped green tomatoes (about 4 medium)
2 cups chopped onions
2 cups chopped sweet green peppers (about 4 medium)
1 cup chopped sweet red peppers (about 2 medium)
3 ¾ cups vinegar (5%)
3 tablespoons canning salt
2 ¾ cups sugar
3 teaspoons celery seed
3 teaspoons dry mustard
1 ½ teaspoon turmeric

Combine chopped vegetables; sprinkle with the 3 tablespoons salt. Let stand 4 to 6 hours in a cool place. Drain well. Combine vinegar, sugar and spices; simmer 10 minutes. Add vegetables; simmer 10 minutes. Bring to a boil.

Pack boiling hot relish into hot jars, leaving 1/2-inch headspace. Remove air bubbles. Wipe jar rims. Adjust lids. Process 10 minutes in a boiling water bath.

If you've never preserved before, consider attending public classes held by UC Master Food Preserver Programs around the state. Find your program and get started!

Posted on Tuesday, December 1, 2015 at 7:09 AM
Tags: holidays (1), master Food Preserver (7), MFP (1)

Apple-tunity: Preserving the fall apple harvest

Fall marks the height of apple season in California. With an abundance of apples available at an affordable price, it is the perfect time to preserve.
With colorful, dried leaves flitting about the streets and winter holidays on the horizon, fall is in full swing. But what does this mean from the perspective of a seasonal preserver? What can be done now that the prime abundance of summer tomatoes is but a fond memory or a dream for next year?

For some, it's time to wind down the season of preserving, but for others, this time of year provides a field of apple-tunity. Yes, the land of ample – I mean apple – opportunity. Here's a few ideas to get anyone started – no canning skills required!

“Home food preservation of apples and other seasonal fruits and vegetables allows families access to a wider variety of healthy foods throughout the year,” says Missy Gable, co-director for the UC Master Food Preserver Program. “In a time where food preservation is becoming increasingly more popular, it is critical for home preservers to follow research-based methods and recommendations to help ensure the preserved foods are safe for consumption.”  

A variety of fruit butters make a perfect holiday gift. Photo: Sue Mosbacher

To keep it simple, let's look to the freezer as a means to store the apple bounty. There are researched and approved recipes for apple butter, apple jelly, baby food, applesauce, and sliced apples. Even amongst something as simple as sliced apples, you can choose to add some variety in the way you pack them, weather it is in syrup, sugar, or as a dry pack. Syrup packs are good for using in uncooked desserts or fruit cocktail. Sugar and dry packs are perfect for pies. Plan ahead and follow the method that makes the most sense for your season of life.


Another method for keeping apples is dehydrating. In fact, it rivals freezing in its simplicity. Think rings, wedges and chips. In preparing the crispy treat, remember to pretreat the slices to prevent browning. It can be as simple as making a solution of 2 cups water with 3000mg ascorbic acid (crushed Vitamin C tablets), and dipping the slices for 3 to 5 minutes. Place the apple slices in a dehydrator for six to 12 hours and voila, apple pieces abound for use as granola mix-ins, oatmeal toppings, or a crunchy snack.

A decorated fruit leather is a fun and healthy snack for young children. Photo: Lillian Smith
In a recent workshop titled “Gifts from the Kitchen,” the UC Master Food Preserver Program of Sacramento County recommended making homemade fruit leather using applesauce. Make your own applesauce, or you can even use store-bought, and convert it into a delicious fruit leather. Smooth the applesauce out to one-eighth-inch thickness over a lined dryer tray or rimmed cookie sheet and dehydrate. Decorate your leather in colors by dyeing with spices such as cinnamon, using red candies or even gelatin. Use cookie cutters to make fruit leather shapes as depicted in the photo. Get creative and have fun; now is the time to let those apples shine!

For more information about apples, download the UC ANR publication Apples: Safe Methods to Store, Preserve, and Enjoy. Detailed recipes and preservation practices alluded to in this article can be found on the National Center for Home Food Preservation site, the Ball site, and in So Easy to Preserve.

If you'd like to learn more in-depth knowledge about safe home food preservation, check out the UC Master Food Preserver Program. They hold public classes by county as well as extensive training programs for qualified applicants.

Posted on Tuesday, November 3, 2015 at 8:37 AM

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