Food Preservation for Food Processors II An interactive module about acidified and acid foods Module designed by Julie Garden-Robinson, PhD, RD, LRD, Food and Nutrition Specialist (2014)

 Welcome to the second module on food preservation for food processors.  You will need to know the information from Food Preservation for Food Processors I before beginning this module.

Don’t get discouraged, your retirement homes are at your fingertips. Now that you know the basics about food preservation, this module will walk you through the regulations and requirement for acidified foods.

The following tips will help you navigate through each module.  Click to go back and to move forward in the module.  Before you begin you’ll take a pretest. The pretest will open in a new window. When you are finished with the pretest close the window to return to the module.  A symbolizes a question slide. You’ll need to click your mouse once to see the answer.  Click on words that are underlined for their definition.

 Click this button to return to your position in the module after reading the definition slide.  When you are finished with the module you will take a post-test. The post-test will open in a new window. When you are finished with the post-test close the window to return to the module.

Pretest  Before we begin let’s take a pretest to see how much you already know. Click here to begin the pretest.Click here to begin the pretest.

Acidification Now that you have some background about the other methods of preserving we’ll talk about the acidification process, when to use the acidification process and rules and regulations to follow with the acidification process.

According to the Food and Drug Administration, foods fit into three classes: 1. Acid 2. Low acid 3. Acidified Foods fall into these classes based on their natural acidity. Acidity is measured based on the pH scale.pH

pH according to food class  Low acid foods have a pH above 4.6  Acid foods have a pH of 4.6 or lower*  Acidified foods are low acid foods that have an acid or acid ingredients added to them to create a final equilibrium pH of 4.6 or lowerequilibrium pH *Tomatoes and tomato products having an equilibrium pH of 4.7 and lower are classed as acid foods

pH Values of Foods pH ValueFood Example 2Limes 3Grapefruit 4Peaches 5Carrots 6Beans 7Black olives

Are stewed tomatoes with a pH of 4.7 a high or low acid food? A. High B. Low Click the forward button to see the answer.

Are stewed tomatoes with a pH of 4.7 a high or low acid food? A. High B. Low Products with a pH of 4.6 and lower are considered high acid foods with the exception of tomatoes and tomato products. Tomatoes and tomato products with a pH of 4.7 are still considered high acid.

Water Availability  The amount of water available for microbial growth.  Bacteria grow in moist environments. The higher the water availability the greater the risk for microbial growth.  Adding a solute like salt or sugar “soaks” up the water making it unavailable for bacterial growth.

Water Availability Scale 0 aW Bone Dry Pure Water 0.2aW Very Dry (instant coffee, milk powder, etc.) 0.99 aW Moist Fresh Food (meat/fish) 0.6aW Dried Fruit 0.8 aW 1 aW Jams and Jellies A water availability less than 0.6

What is the water availability of dried fruit? A. 0.2 B. 0.4 C. 0.6 Click the forward button to see the answer.

What is the water availability of dried fruit? A. 0.2 B. 0.4 C. 0.6 “C” is the correct answer.

Water Availability  Bacteria, mold and yeast need a certain amount of water available to grow. As the water availability decreases, bacteria, mold and then yeast cease to grow. Bacteria stop growing below 0.85 aW Molds stop growing below 0.75 aW Yeast stop growing below 0.6 aW

Fill in the blank: Bacteria stop growing when the water availability is ____ and lower? A B C D Click forward to see the answer.

Fill in the blank: Bacteria stop growing when the water availability is ____ and lower? A B C D “C” is the correct answer.

Water availability of some common foods Food Example Water Availability Cheese Spread 0.95 Soy sauce0.80 Fudge sauce0.83 Soft moist pet food 0.83 Peanut butter0.70 Dry milk0.70 Liverwurst0.96 Salami0.82 A higher water availability number means the product has more moisture for bacterial growth.

True or False: Adding salt to a food increases its water availability. a. True b. False Click the forward button to see the answer.

True or False: Adding salt to a food increases its water availability. a. True b. False False, adding a solute like salt, decreases the water availability. The salt “soaks” up water making less water available for bacterial growth.

Acidified Foods An acidified food:  is a low acid food having acid(s) or acidic food(s) added to it.  has a natural pH greater than 4.6.  has an natural water availability greater than.85.

Which of the following statements is true? a. Acidified foods have an equilibrium pH greater than 6. b. All ingredients in an acidified food must have a natural pH less than 4.6. c. Acidified foods have an equilibrium pH less than 4.6 and a water availability less than Click the forward button to see the answer.

Which of the following statements is true? a. Acidified foods have an equilibrium pH greater than 6. b. All ingredients in an acidified food must have a natural pH less than 4.6. c. Acidified foods have an equilibrium pH less than 4.6 and a water availability less than “C” is the correct answer. Acidified foods can have ingredients with pH levels greater than 4.6 as long as the equilibrium pH level of the final product is less than 4.6.

Why a pH of 4.6?  A pH of 4.6 stops the growth of a dangerous microorganism called Clostridium botulinum

Clostridium Botulinum  Creates a toxin that causes the deadly disease botulism  Clostridium botulinum spores are heat resistant Pasteurization and cooking temperatures below 212 F cannot destroy this microorganism Proper acidification and pH levels can control and inhibit its growth

Symptoms of botulism  double-vision  droopy eyelids  difficult to talk or swallow  paralysis on both sides of the body that progresses from the neck down, possibly followed by difficulty in breathing *Botulism is fatal and is considered a medical emergency. double-vision

Foods linked to botulism  Canned Corn Peppers Green beans Soups Beets Asparagus Mushrooms Ripe olives Spinach Tuna fish Chicken and Chicken livers Liver pate  Luncheon meats  Ham  Sausage  Stuffed eggplant  Lobster  Smoked and salted fish  Canned Corn Peppers Green beans Soups Beets Asparagus Mushrooms Ripe olives Spinach Tuna fish Chicken and Chicken livers Liver pate

*C. botulinum can grow and produce toxins in any product that allows spore survival, and is not heated to a safe temperature before consumption. *Almost any type of food that is not very acidic (pH above 4.6) can support growth and toxin production by C. botulinum. Source:

Example of foods that can be acidified  Beans  Cucumbers  Artichokes  Cabbage  Cauliflower  Pudding  Tropical fruits  Fish  Peppers *A combination of these is also considered an acidified food. Salsa is an example.

Foods that are not classified as acidified foods  Carbonated beverages  Jams, jellies, preserves  Acid foods with small amounts of low-acid food(s) that don’t significantly affect the pH of the acid food  Foods that are stored, distributed, and sold under refrigeration

Which of the following are acidified foods? Click forward to see the answer. Salsa Pudding Pickles Carbonated Beverage Milk

Salsa Pudding Pickles Even though tomatoes are a high acid food, salsa has many low acid foods and needs to be acidified to be safe. Cucumbers are a low acid food to which an acid is added to make pickles. Pudding is a combination of low acid ingredients to which an acid is added for safety.

Now that we know which foods are considered acidified foods, we’ll explain the processing requirements you must follow to sell these foods to the public.

Scheduled process  Process selected by processor as adequate for use under the conditions of manufacture for a food in achieving and maintaining a food that will not permit the growth of microorganisms having public health significance. Whew! Source:

Registration and Process Filing  Commercial processors must register with the FDA on form FDA Form must be filed no later than 10 days after the firm starts operating.  Must file a scheduled process with the FDA on form FDA Form must be filed no later than 60 days after registration, and before packing any new product.

How to get FDA forms  Contact the FDA in writing requesting forms at the following address: LACF Registration Coordinator, HFS-618 Food & Drug Administration Center for Food Safety & Applied Nutr. 200 C Street, S.W. Washington DC Or download from: orms/CFSAN.html orms/CFSAN.html

Scheduled Process  Scheduled processes must include: information essential to produce a safe product  maximum equilibrium pH  other critical factors  heat processing  preservatives used, and their levels as appropriate.

 An operating supervisor should be on duty or accessible during processing, packing operations and container closing.  The operating supervisor must attend a specialized school and satisfactorily complete the required portions to be in compliance. Operating supervisors can obtain training at an approved Better Process Control School or an approved Acidified Food GMP School.

Processing operations The manufacturer must enforce quality control procedures to ensure that finished foods do not present a health hazard.

Processing operations  Acidified foods must be thermally processed to an extent sufficient to destroy the vegetative cells of microorganisms of:thermally processed Public health significance  Clostridium botulinum  Escherichia coli O157:H7  Salmonella  Listeria monocytogenes Nonhealth significance capable of reproducing in the food under the conditions which the food is:  Stored  Distributed  Retailed  Held by user

Processing operations  The final product must have a pH of 4.6 or lower within the time allowed in the scheduled process and maintained in all finished products The pH must remain below 4.6  Manufacturing must be in accordance with the scheduled process

Coding  Each product needs to be marked with a permanent code that includes: the processing establishment the product year day packing period  The code needs to be changed at least every personnel shift change.

Learn more about food preservation with the following on-line resources  National Center for Home Food Preservation  FDA- Acidified and Low Acid Canned Foods  Food Preservation and Storage  Don’t forget to take the post-test! NDSU is an equal opportunity Institution.

Post-test Let’s see what you’ve learned. Click here to begin the post-test.Click here to begin the post-test.

pH  pH values range from  Products with a pH below 7 are acidic  Products with a pH above 7 are basic  Products with a pH of 7 are neutral  The lower the pH the more acidic the product Click the button to return to your position in the module.

Equilibrium pH The pH of the acidified food after all the components have reached the same acidity For example: The pH of salsa after all the ingredients have mixed and reached the same pH Click the button to return to your position in the module.

Thermally processed  Application of heat to food before or after sealing in a hermetically sealed container, for a period of time and at a temperature scientifically determined to be adequate to ensure destruction of microorganisms of public health significance. Click the button to return to your position in the module.