Presentation on theme: "Lets Get Ready to Preserve – An Update on Canning Research June 3, 2013 Barbara Ingham Paola Flores."— Presentation transcript:
Lets Get Ready to Preserve – An Update on Canning Research June 3, 2013 Barbara Ingham Paola Flores
Need Help with Tonights Program? Help Desk: 800-442-4614 Phone in to todays program o Toll: 630-424-2356 o Toll Free: 855-947-8255 o Passcode: 6774570# Tonights program archived: o www.foodsafety.wisc.edu/preservation.html www.foodsafety.wisc.edu/preservation.html
Tips for a Successful Canning Season 1)Start with a research-tested recipe. Just because a recipe is in print, doesnt mean its safe for you and your family. 2)Use up-to-date recipes. We all want to continue with those tried- and-true recipes, but canning recommendations can, and do, change! 3)Start with equipment in good working order. Test equipment before use. Be sure to test dial canners! 4)Assemble jars, lids and other equipment. Use jars, lids and other equipment designed for home food preservation. 5)Leave your creativity behind. Follow an up-to-date, tested recipe.
Resources for You! Extension recipes are designed to help you prepare safe, high quality foods for family and friends. UW-Extension www.foodsafety.wisc.edu www.foodsafety.wisc.edu National Center for Home Food Preservation www.uga.edu/nchfp www.uga.edu/nchfp o How do I….Can? Freeze? Pickle? University of Georgia publications o So Easy to Preserve ( Book and Video ) o www.setp.uga.edu www.setp.uga.edu Ball Canning www.freshpreserving.com www.freshpreserving.com
UW-Extension Web site: www.foodsafety.wisc.edu A-Z Index Canning, Freezing, Drying Safe Home Food Preservation: Bulletins (recipes) Elevation guide Links to recommended websites
How do I? ….. Can, Pickle, Dry Univ. of Georgia: So Easy to Preserve Flavored Vinegars Jellied Products without Sugar URL: www.uga.edu/nchfp
Getting Started…Recipes Use ONLY up-to-date, research-tested recipes! Current canning instructions date from 1994 Dont (necessarily) do what Mom said (or did)! o Add ACID to tomato products when canning o Avoid using ALUM in pickling o Use LIME with care when making pickles o Be sure to include a heat-processing step as part of each home canning recipe. No tested recipe….no problem. Prepare the recipe and store refrigerated or frozen. 7
Getting Started…Canners Boiling Water Canners Use for naturally high acid foods (most fruits) or acidified foods (pickles, salsa) A rack is needed to lift jars off the bottom Use with a tight-fitting lid Processes food at 212°F 8
Getting Started…Canners Pressure Canners Use for low acid foods (meat, vegetables) Dial gauge – checked every year for accuracy! Weighted gauge – inspect for proper function Fitted with a rack Processes food at 240°-250°F 9
How do we know which canning method to use ? What is the pH (acidity) of the food? below pH 4.6 above Boiling Water Canning Fruits, Pickles, Salsa Pressure Canning Meat, Vegetables 10 HIGH AcidLOW Acid
What if….. For high acid foods you didnt have to: Wait for all that water to boil? Use so much water? Take so much time to process food? Introducing….The Atmospheric Steam Canner Lack of research means that Extension does not currently support the use of atmospheric steam canners.
About Paola 1 ST year Food Science M.S. student Graduated from Purdue University B.S. in Food Science Getting married in December!
Canning What is it? – Preserving food either at home or commercially Why is it important? – Preserving the harvest – extending shelf life – Catering to special dietary needs – Growing consumer trend What research has already been done? – Boiling water canners & pressure canners (USDA Complete Guide to Home Canning, 2009) nchfp.uga.edu/publications/publications_usda.html
pH, Heat, and Safe Home-Canned Foods Acid or Acidified Foods – Heat is required to destroy target pathogens and vegetative cells of spoilage organisms – High acid (pH <4.6) ensures that spores of Clostridium botulinum will not germinate – E. coli O157:H7 is the target pathogen in thermal steps – Yeasts & Fungi or heat resistant enzymes are also of interest as they pertain to food spoilage Pasteurization (heating): – Removes air entrapped in product and in headspace, allowing a vacuum seal to form on cooling – Helps to ensure that a strong hermetic (air-tight) seal forms
Research is key for safe home- preserved food Use of an up-to-date, research tested recipe is key for home canners. Sources of information: – National Center for Home Food Preservation www.uga.edu/nchfp/ www.uga.edu/nchfp/ – Ball Canning www.freshpreserving.comwww.freshpreserving.com – Extension bulletins www.foodsafety.wisc.edu/preservation.htmlwww.foodsafety.wisc.edu/preservation.html And a whole lot of untested, sometimes scary information posted to the web that is not tested – Canning fish in the dishwasher – Using a washing machine to clean cucumbers prior to pickling – Oven canning of meat – Filling salsa into jars, applying lids, and putting on shelf – Filling hot jam into jars, sealing and inverting
Steam Canners What are they? How are they assumed to work? – Heat transferred from steam through jar and into food Why are they growing in popularity? What foods could be safely canned in a steam canner? – Processing times have not been adequately researched to allow Extension educators to recommend use of these canners.
Research Timeline Spring/Summer 2013 Goal: To establish, under varying conditions, heating patterns in an atmospheric steam canner (ASC) and compare those to patterns in a boiling water canner (BWC) – Establish come-up time for each canner, i.e. when do we start the clock? – Determine the time for the cold spot in the center of a jar to reach a predetermined temperature in an ASC and BWC. Fall 2013 Goal: Using inoculated pack studies, to verify processing times for ASC (atmospheric steam canner) as compared to established processing times for BWC (boiling water canner) – Inoculate with E. coli O157:H7, Salmonella spp., Listeria monocytogenes Spring 2014 Goal: Determine if a re-configured BWC can be used as an ASC Goal: Updating of national outreach materials to include ASC recommendations, where appropriate
Methods & Procedures ASC – Hot (~180˚F) or Room Temp (~75˚F) tomato juice – Quarts (7), Pints (8), Half Pints (8) – Start with room temperature environment & heated jars – 4 thermocouples at varying depths – Measured come up time and venting time 1 2 3 4 Vent hole
Time for the canner to reach the processing temperature: ~18 minutes Example Data Graph
Results to Date Heating patterns depend on jar placement and quantity Generally: – Smaller jars will take less time – Smaller quantities will take less time – Higher temperatures will take less time – Statistics are showing that process is not highly variable when comparing similar environmental factors Many variables (for us and consumers) : Stove Room Thermocouple variability Visual cues & matching with concrete data Jar placement Amount of jars
Calculations Compare area under curve to analyze differences between runs Calculate Thermal Process Lethality. Process lethality can be compared across runs to determine how to adjust tested recipes for use in an Atmospheric Steam Canner.
Future Research – Processing time: Time period that given jar size should be held at a set processing temperature in order to achieve the required thermal destruction of microorganisms likely present in slowest heating point of container. – Size of the jar, size of the food, consistency of the canning liquid, etc. all have an effect on how heat penetrates through the product Convection (liquid food) = ¾ inch from bottom Convection & Conduction (liquid & solid) = center of jar
Thermocouple inserted into coldest spot within jar
Expected Outcomes Determine what adjustments need to be made to Boiling Water Canning instructions so they can be safely used for Atmospheric Steam Canners. – Research results sent out for review Fall 2013 – Results published ~Spring 2014 Write consumer guide to steam canning – Provide consumers simple instructions for safe steam canning of high-acid foods Research project results will be posted to: www.foodsafety.wisc.edu
The Bottom Line Assuring safety in Atmospheric Steam Canners: Use ONLY for fruits and acidified vegetables Use ONLY with tested recipes Use the correct amount of water & approved equipment Time once a full column of steam is emitted (8-10) Keep canner steaming the entire time Process for the full time required
And next …in our Lunch & Learn series June 17, 2013 12 noon – 1 pm Making Jams & Jellies Preserve the taste of perfectly ripe fruit in homemade jams and jellies and consider new gift ideas in jellied fruit and vegetable products. Archives will be posted to: www.foodsafety.wisc.edu