Presentation Transcript
Current Issues in Food Preservation: Current Issues in Food Preservation by
Martha Stone, Ph.D.
Mary Schroeder, M.S., R.D. Colorado State University
Cooperative Extension
Desktop Training
June 21, 2006
Overview: Overview Jams and Jellies
Without added sugar
With sucralose or Splenda®
Using Clear Jel
Review on tomato canning
USDA recommendations
Salsa
Food Processing Support Services
Jams and Jellies: Jams and Jellies Traditional products either made with:
1. No added pectin (natural pectin in fruit or juice)
i.e. Long Boil Method
2. Added pectin (dry or liquid)
Regular
Modified
Require certain amounts of sugar and acid to gel
Too little sugar can allow yeasts and molds to grow
Artificial Sweeteners (like Splenda®) cannot be used!
Traditional Jams and Jellies:Ingredients: Traditional Jams and Jellies: Ingredients Pectin
Stabilized in juice by :
Water shell
Negative charge
May be naturally in fruit or added
Acid
Adds positive charge
May be in fruit or added
Sugar
Dehydrating agent; removes water shell from pectin
Added ingredient
65% sugar concentration in hot syrup
Preservative; allows for short processing in boiling water bath
Pectin and Acid Proportions: Pectin and Acid Proportions Testing Pectin:
Allow ¾ cup sugar per cup juice/fruit
To test pectin, measure 1/3 cup fruit/juice and ¼ c. sugar in saucepan.
Bring to rapid boil, until sheets from spoon
Pour into clean hot glass and cool.
If jelly-like, will gel.
Pectin and Acid Proportions: Pectin and Acid Proportions Testing Acidity:
Heat to boiling: 1 tsp. lemon juice, 3 T. water and 1/2 tsp. sugar.
Compare by tasting fruit to mixture. If fruit isn’t as tart, add 1 T. lemon juice to each cup fruit/juice
Traditional Jams and Jellies:Method: Traditional Jams and Jellies: Method Prepare jars and lids
Prepare fruit/ extract juice
Add ingredients
Acid
Commercial pectin (liquid or powder)
Sugar
Boil to 65% sugar concentration
Endpoint temperature (8◦F higher than boiling point of water)
Timing (when pectin is added)
Fill and seal containers (1/4 “ headspace)
Process in boiling water bath
Scenario #1: Scenario #1
Someone brings you a freshly made jelly sample with sugar crystals? What is the most likely cause?
Scenario #2: Scenario #2
Someone brings you a traditional jelly that did not set up properly (i.e. no gel formed). What are possible reasons?
Function of Sugar: Function of Sugar Gel formation
Preserving agent
Adds flavor
When remove sugar:
Changes in consistency (melting point)
Texture changes (some like jello!)
Flavor
It is challenging to get the same quality product when sugar is removed !
Scenario #3: Scenario #3 Someone in your county calls you. She has used her grandmother’s recipe for making strawberry preserves (with fruit and sugar only) for many years. Since she was recently diagnosed with diabetes, she wants to reduce the sugar in this recipe. Can she do this? What would you tell her?
Jellied Products without added Sugar : Jellied Products without added Sugar 4 Methods:
1. Long-Boil Method
2. Regular Pectin with Special Recipes
3. Special Modified Pectins
4. Recipes using Gelatin
Jellied Products withoutadded Sugar: Jellied Products without added Sugar Long-Boil Method
Boiling fruit pulp for extended periods of time
Will make product thicken and resemble a jam, preserve, or fruit butter
Artificial sweetener may be added
Example: apple butter
Use processing times for canning fruit!
i.e. Apple butter- traditional vs. no sugar
Jellied Products withoutadded Sugar: Jellied Products without added Sugar
Regular Pectin with Special Recipes
Formulated so that no added sugar is needed
Contain some sugar
Artificial sweetener is often added
Pectin packages of different brands vary in weight from 1.75 to 2 ounces
Best to use recipes enclosed in package!
Jellied Products without Added Sugar: Jellied Products without Added Sugar
Special Modified Pectins
(Low Methoxyl Pectins)
Follow directions on package
Some products made with less sugar; some with artificial sweeteners
Sure Jell TIP: To enhance the sweetness and color of the jam – prepare as directed, substituting 1 thawed can (12 oz.) frozen white grape juice or apple juice concentrate in place of the water.
Making Pectin Jam or Jelly without Sugar: Making Pectin Jam or Jelly without Sugar Modified (low methoxyl) pectin must be used
Pectin has “no sugar needed” on label
Require divalent ions such as Ca++ or Mg++ to form gel
Ions usually added to the pectin (as purchased)
Ca++ powder may be in separate packet in box and added in an additional step
Sometimes gums are added to pectin mixtures for texture
Non-nutritive sweeteners added for flavor
Low Methoxyl Pectins: Low Methoxyl Pectins “Light”
“Less sugar”
“Low sugar”
“No sugar needed”
Brands available in this area:
Ball Fruit Jell
Sure-Jell
MCP
Mail Order:
Mrs. Wages Lite Home Jell
Pomona’s Pectin
Jellied Products withoutadded Sugar: Jellied Products without added Sugar
Recipes Using Gelatin (instead of pectin)
Unflavored gelatin is the “thickener”
Artificial sweetener is often added
Cannot be heat processed
Used for making refrigerator/freezer jams and jellies
Lots of Interest in Using Splenda®: Lots of Interest in Using Splenda®
Used in place of sugar in making low calorie:
Baked goods
Jams/Jellies
Pie Fillings
Will discuss the trade-offs in using Splenda® in food preservation.
What is Splenda® (Sucralose) ?: What is Splenda® (Sucralose) ? Splenda® Brand Sweetener = Sucralose
No-calorie sweetener
Approved for use in 80+ countries
Approved in the U.S. since 1998
No warning is required
extensively studied for safety
Chemical Structure: Chemical Structure Sucrose and Sucralose
Market Forms of Sucralose: Market Forms of Sucralose Splenda ® Granular
Only form for use in food preservation
= 96 kcals/cup vs. Sugar =770 kcals/cup
Splenda ® Sugar Blend for Baking
Bake with half the sugar
Splenda ® Brown Sugar Blend
Bake with half the sugar
Splenda ® No Calorie Sweetener
Packets, pouches
600 times sweeter than sugar
Characteristics: Characteristics Largely unabsorbed
Not broken down for energy or to smaller compounds
Does not de-chlorinate
Eliminated quickly
Non carcinogenic
Highly water soluble; poorly soluble in fats
MW=400 (sucrose MW=342)
Characteristics: Characteristics Tastes similar to sugar
600 x sweeter than sugar
Stable to high temperatures (even UHT pasteurization)
Does not caramelize or brown like sugar
Long shelf life
Stable in acidic media (soft drinks)
Stable in dry applications
Benefits: Benefits Tastes like sugar (no aftertaste)
Heat stable
Can help control caloric intake
Diabetes (not recognized as sugar or carbohydrate by the body)
Does not promote tooth decay
Long shelf life
Ingredient compatibility (water soluble)
Problems with Pectin Jams and Jellies containing Splenda®: Problems with Pectin Jams and Jellies containing Splenda® Regular pectin (HMP) will not gel
Must use low methoxyl pectin (LMP) with calcium added
Some no-sugar needed pectin still will not gel with Splenda® Granular
Best to use recipes that have been tested!
Successful Trials at Univ of GA: Successful Trials at Univ of GA Jams/Jellies made using Splenda® and low methoxyl pectins.
Pomona’s Universal Pectin
Mrs. Wages Lite Home Jell
Ball Fruit Jell No Sugar Needed Pectin
(All contain monocalcium phosphate which allows the pectin to set without sugar)
Read ingredient list!
University of GeorgiaSplenda® Trials: University of Georgia Splenda® Trials Tested jams made with red plums, fresh peaches, fresh strawberries, and frozen whole strawberries.
Followed same methods for adding Splenda® as suggested for adding sugar
Experimented with varying amounts of Splenda®
Recommendations Based on Testing Results: Recommendations Based on Testing Results 1.5 cups of Splenda Granular is the right amount to try for recipe quantities given on package inserts
Taste differences noted:
Mrs. Wages Lite Home Jell products seemed more tart than product made with Ball Fruit Jell
Increasing Splenda led to undesirable aftertaste
Results: U of GA- Splenda® Jams: Results: U of GA- Splenda® Jams
Much lower yield than package inserts suggest!
When 1.5 cups Splenda are substituted for up to 3 cups sugar, yield will be decreased
For example:
Mrs. Wages: Use 5 cups prepared fruit and add 1.5 cups Splenda. Yield = 3 pints instead of suggested 5-6 pints.
More like “spreadable fruit” than traditional jam
Ball: Use 1.5 cups Splenda. Yield = 4.5 pint jars instead of suggested 6 pints.
Results: U of GA - Splenda® Jams: Results: U of GA - Splenda® Jams Inconsistent texture
For example:
Mrs. Wages products were usually thicker
even too stiff in some cases
Spreadable fruit (not jam consistency)
Results: U of GA - Splenda® Jams: Results: U of GA - Splenda® Jams Trapped air
Foam layer in the headspace
Color (pale, cloudy)
Texture
Flavor (after taste-if too much used)
Appearance
So….can people get desirable or acceptable fruit spreads with Splenda® Granular ?
(weigh pros and cons…individual choice)
Safety Recommendations for LMP Products containing Splenda®: Safety Recommendations for LMP Products containing Splenda® No storage or shelf life information available
Process sealed jars in boiling water bath
10 minutes* at sea level
Add 1 minute for each 1000 ft above sea level
Refrigerate after opening to minimize changes in flavor, sweetness, and color
Refrigerator/Freezer Jelly without added Sugar: Refrigerator/Freezer Jelly without added Sugar Juice
Unflavored gelatin
Non-nutritive sweetener
Liquid = Saccharin
Powder = Sucralose
Refrigerator Jelly with Splenda®: Refrigerator Jelly with Splenda® Ingredients:
2 packages or 2 tablespoons unflavored gelatin
4 ½ cups bottled unsweetened fruit juice
½ cup Spenda Granular
Yield: about 4 half-pints
Refrigerator Jelly with Splenda®: Refrigerator Jelly with Splenda® Procedure:
Soften gelatin in juice
Bring to a rolling boil
Boil 1 minute
Remove from heat
Stir in Splenda® granular
Pour into hot, clean jars or plastic refrigerator containers
NOT shelf-stable. Store in refrig (1 mo) or freezer
Different texture but easy to make!
Using Clear Jel ®: Using Clear Jel ® Modified cornstarch-can replace flour, cornstarch or tapioca as a thickener
1 tbsp cornstarch = 1 ½ tbsp Instant clear Jel ®
2 tbsp flour or tapioca = 1 tbsp Instant Clear Jel ®
Types of Clear Jel® available
Instant
Does not require heat to thicken
Product will thicken once liquid is added
Ie. Instant puddings, gravies, pie fillings
Mix w/ equal amounts sugar; stir into food; wait 10 min.
Regular
Must be heated to thicken
Preferred type for products to be canned
Jams/jellies, canned pie filling
Mix w/ cold H20 before adding to food; heat 10 min.
Clear Jel® Advantages: Clear Jel® Advantages Clear in color when cooked
Excellent stability
Remains smooth
Prevents liquid separation and curding after foods have been frozen.
Excellent for cream sauces, custard, puddings
Clear Jel® Advantages: Clear Jel® Advantages For Jams and Jellies:
Less expensive than pectin
Sugar can be adjusted without losing jelling capacity
Recipes can be doubled, tripled or halved
Jam may be frozen or processed in boiling water bath for 10 minutes (plus altitude adj).
Clear Jel® in Jams/Jellies: Clear Jel® in Jams/Jellies Not an exact science (small batch 1st)
Can use any recipe-if processed 10 min. or frozen
Use pint or ½ pint jars
Hint: To dissolve more easily in liquid, mix with some sugar before adding to fruit or juice
Rule of Thumb:
Use 7 tbsp ClearJel ® for cooked jams
Use 3 to 4 tbsp ClearJel ® for freezer jams
Clear Jel® Resources: Clear Jel® Resources
Univ. of GA NCHFP “Purchasing and Using Clear Jel®”
www.uga.edu/nchfp/publications/uga/purchasing_using_clearjel.pdf
Blue Chip Group, Inc.
www.bluechipgroup.net/clearjel.html
WSU Skagit County Cooperative Extension
“Using Clear Jel ®” including jam recipes: http://skagit.wsu.edu/FAM/publications/using%20clear%20jel%2003.pdf
Pectin Resources: Pectin Resources Splenda® website: 3 no-sugar jam recipes using Splenda ® Granular and Sure Jell ® for Low Sugar Recipes at: www.splenda.com
Kraft Kitchens: links to no-sugar jam recipes and pectins at: http://www.kraftfoods.com/
Sure Jell ® website: www.kraftfoods.com/surejell/
Pomona’s Universal Pectin
Phone and Hotline: 413-772-6816
Mrs. Wages ® Pectins: link to recipes at www.mrswages.com/
Review of Tomato Canning: Review of Tomato Canning Key is having sufficient acidity for safety
(to prevent growth of Clostridium Botulinum)
Acidity level measured by pH scale
Due to variations in natural acidity, tested recipes call for added lemon juice
pH Scale: <4.6 needed for safety: pH Scale: <4.6 needed for safety
Acidity Test-ND State Univ. : Acidity Test-ND State Univ. North Dakota State University Extension
Tested pH levels of 15 varieties of tomatoes and salsa made with and without lemon juice
pH of tomatoes (4.93-5.09)
pH of salsa with lemon jc (4.09-4.32)
pH of salsa without lemon jc (4.72-5.0)
Must have pH <4.6 to be safe!
http://www.ext.nodak.edu/food/lemnjuic.pdf
pH Scale: <4.6 needed for safety: pH Scale: <4.6 needed for safety
Tomato Acidification: Tomato Acidification For whole, crushed, or juiced tomatoes:
Per quart of tomatoes, add:
2 T. bottled lemon juice OR
½ tsp. citric acid
Per Pint:
1 T. bottled lemon juice OR
¼ tsp. citric acid
Add directly to jars before filling
May want to add sugar to adjust for tartness
If don’t acidify, pressure can as a low-acid food.
USDA Tomato Canning Directions: USDA Tomato Canning Directions Based on USDA Complete Guide to Home Canning (1994):
Crushed
Hot pack only. Use cooked quartered tomatoes
Whole or halved; with liquid
Raw or Hot pack, with boiling water or tomato juice to cover
Whole or halved; no added liquid
Hot or Raw pack
Tomatoes are pushed tightly into jars to create juice as the jar fills
Salt is optional
USDA Tomato Canning Directions: USDA Tomato Canning Directions
Tomato Juice
Hot pack only
Tomato-Vegetable Juice Blend
Hot pack only
Add no more than 3 cups vegetables for each 22 lb. tomatoes used.
Tomato Sauce
Hot pack only
Processing times:
Water Bath: time per elevation-see chart
Pressure Canning:
Dial gauge: 10 lb psi + ½ lb/1,000 ft.
Weighted gauge: 15 lb psi at 1,000-10,000 ft.
What about salsa?: What about salsa? pH is influenced by:
Tomato variety, stage of maturity
Acidification
Added ingredients
Questions
“Can I change the ingredients in my salsa recipe?”
“Can I thicken my salsa with flour or cornstarch?
“What about recipes from friends or on the internet?”
Use only tested recipes! Risk of C. botulinum not worth the risk.
What would you do?: What would you do? John Q. Public has a salsa with corn and black beans. He wants to know if it should be processed in boiling water or steam pressure canned.
Recommendation?
Did the formula change?: Did the formula change? Enchilada sauce
Client stated no formula change
Flour as thickener
Replaced flour with gum
Would this small change in formula cause a change in pH?
Why or why not?
CSU Food Processing Support Services: CSU Food Processing Support Services Food Processing Support Lab- Dept.FSHN
Nutrient Analysis
$80 per formula
Based on ingredients/formulation provided by client
Initial pH screen $15/sample
pH testing $108
Based on values from 3 samples from 3 different batches
Sample=final product in form sold by client
CSU Food Processing Support Services: CSU Food Processing Support Services
Water Activity
$90 ($30/sample)
Samples from 3 different batches
Color Assessment
$30/sample
Shelf-life testing
$30 per week of testing
1 week under accelerated conditions =
1 month at room temperature
To provide minimum/maximum shelf-life of product
Client must provide 10 units/sample evaluation
CSU Food Processing Support Services: CSU Food Processing Support Services Product Development Consultation
$75/visit
Other services: Fees negotiated based on client needs
Go to:
www.fshn.cahs.colostate.edu/foodsupport.asp/
Denver Enterprise Center, Inc.
USDA-approved production facility
3003 Arapahoe St. Denver, CO 80205
1(303) 296-9400
Tested Salsa Recipes: Tested Salsa Recipes Washington State Univ. Extension Publications:
www.wsu.edu/
Salsa Recipes for Canning #PNW395
CSU CooperativeExtension Resource Center
www.cerc.colostate.edu/
Salsa Recipes for Canning #XCM-149 $2.75
Food Preservation Resources: Food Preservation Resources University of Georgia
National Center for Home Food Preservation www.uga.nchfp.org
CSU Fact Sheets
#9.302 Food Preservation Without Sugar or Salt
#9.303 Making Jellies
#9.341 Canning Tomatoes and Tomato Products
http://www.ext.colostate.edu/pubs/foodnut/pubfood.html#pres
Food Preservation Resources: Food Preservation Resources USDA Complete Guide to Home Canning (1994)
http://www.uga.edu/nchfp/publications/usda/can_guide_order.html
Master Food Safety Advisor Volunteer Training Manual
www.cerc.colostate.edu/ ($20)
Books
Putting Food By
Ball Blue Book of Preserving -2005 ($8.50)
So Easy to Preserve by Univ. of GA
DVD set ($39.95)
5th Edition Book (any time now?)
Preserving Food at Home: A Self Study (free online Web-CT modules)
http://www.homefoodpreservation.com/
Questions?: Questions?