Food Safety

  1. Potentially Hazardous Food
  2. Selected Food-borne Illnesses
  3. Food Controls

 

 

Potentially Hazardous Foods

Objective: The purpose of this section is to define potentially hazardous food under the California Health and Safety Code.

 

As we will discuss further in class, "potentially hazardous food" under most cases must be stored below 41 degrees F. or above 140 degrees F. These foods have the highest potential for spreading foodborne illness. Its fundamental legal definition is:

food that can support rapid and progressive growth of microorganisms
that may cause food infections or food intoxications.

A legal exception to this definition is Clostridium botulinum. Because of the extreme toxicity of its toxins, rapid and progressive growth is not necessary for botulism. Any growth or toxin production of this organism represents a significant risk.

Because of the significance of potentially hazardous food, the following conditions (defined by law) allow us to determine foods that are not potentially hazardous:

Try the links to the California Health and Safety Code (click first on "food sanitation" given just below, and then select "CURFFL"), and look at the additional distinctions provided under the law. It is one of the most important definitions you will ever work with in the field.

 

  
 
 
 

Selected Food-borne Illnesses

                                         
 
A. Infections                                                
                                                              
   1. Salmonellosis         Salmonella typhimurium        
                            Salmonella enteritidis        
   2. Campylobacter         Campylobacter jejuni          
   3. Listeriosis           Listeria monocytogenes        
   4. Hepatitis             type A = infectious                 
   5. Brucellosis           Undulant Fever                
   6. Trichuriasis          Trichuris thrichiura          
   7. Anisakiasis           Anasakidae family                   
                                                              
 
B. Intoxications  (primarily exotoxins)                                            
                                                              
   8.  Staphyloccoccus       Staphyloccoccus aureus        
   9.  Botulism              Clostridium botulinum               
   10. Perfringens           Clostridium perfringens
 
 
C. Poisonous plants/animals                                   
                                                              
   11. Favism                Vicia faba                    
   12. Snake root            Eupatorium 
   13. Paralytic                                            
       shellfish poisoning                                      
   14. Ciguatera                                            
   15. Scombroid             Scombridae family             
                                                              
 
D. Others                                                    
                                                                   
   16. agent:          Vibrio parahemolyticus
       reservoir:      oceans (variety of seafood)                        
       transmission:   poorly cooked seafood                              
       symptoms:       diarrhea, abdominal cramps (rarely fatal)          
                                                                         
   17. agent:          Bacillus cereus                                    
       reservoir:      soil                                               
       transmission:   especially cooked rice at room temperatures        
       symptoms:       sometimes vomiting, sometimes diarrhea             
                                                                         
   18. agent:          Clostridium perfringens (anaerobic sporeformer)    
       reservoir:      soil; also, GI tract of healthy humans or animals  
       transmission:   spores survive normal cooking,                     
                       then germinate, multiply, and produce toxins       
       symptoms:       diarrhea, nausea; usually no vomiting or fever     
                                                                         
   19. agent:          Copper poisoning                                   
       transmission:   copper in prolonged contact with acid foods or     
                       carbonated beverages                               
                       (e.g., improper vending machines)                  
       symptoms:       vomiting and weakness in < 1 hour (often minutes)  
	
 
 
  
 
 
 

Food Controls    

A. Pasteurization:                                                    
                                                                           
   1. Ultra Pasteurization:   >280 deg. F     for >2 seconds             
                                                                         
 
   2. Ultra High Temperature: 191-212 deg. F. for 1 to .01 seconds       
      (UHT)                                                                               
 
   3. High Temp. Short Time:  161 deg. F      for 15 seconds             
      (HTST)                                                             
 
   4. Holder pasteurizer:     145 deg. F      for 30 minutes             
                                                                         
                                                                         
B. Food and Temperatures:                                             
                                                                           
   5. Thermometers:  required in refrigerators.                          
 
                     should be:   readily visible                        
                                  at the warmest part of the unit        
                                  accurate to 1 degree Centigrade        
                                                                         
 
   6. Stem           designed to check food temperatures                 
      (or probe)     typically has metal stem                            
      thermometer:      with temperature readings at top of thermometer  
                     Restaurant operators must have on the premises.     
                                                                         
 
   7. Maximum        used to check temperatures in dishwashing machines  
      registering                                                        
      thermometer:                                                       
                                                                         
 
   8. Refreezing:    frozen foods may not be thawed and refrozen         
                     (exception: when food is cooked or processed 
                                 after thawing).                                     
 
C. Canning operations:                                                
                                                                            
   1. soaking       reduces spoilage bacteria                            
      and washing:                                                       
                                                                         
   2. sorting       consistent quality of product                        
      and grading:                                                       
                                                                         
   3. blanching:    direct contact with hot water or steam               
                    destroys enzymes (reducing chemical changes)         
                    softens tissues to fit in can                        
                    washes away "raw" flavor                             
                                                                         
   4. exhausting:   heat foods in cans prior to closing can              
                    produces partial vacuum                              
                                                                         
   5. sealing:      secures lid on can                                   
                    hermetic double seam                                 
                    when can cools, lids pull in (concave)               
                                                                         
   6. retort        closed vessel for "sterilization" of food            
      processing:   240 degrees for 30 minutes                           
                                                                         
                                                                         
   7. cooling:      quick cooling minimizes thermophilic bacteria        
                    potential for water contamination through seams      
                    (water must be disinfected)                          
                                                                         
                                                                         
D. Dishwashing:                                                       
                                                                          
   8. Manual      3 compartment sink:                                    
      method:                                                            
                    detergent and warm water:                            
                       good at removing, not killing bacteria            
                       most important step in dishwasing                 
                                                                         
                    rinse: removes detergent before sanitizer            
                                                                         
                    sanitizer:                                           
                       a "polishing" step                                
                       hot water   (180 deg F, 30 seconds)               
                       chemicals and warm water (75 deg F):              
                          chlorine:  100 ppm for 30 seconds              
                          quaternary ammonia:  200 ppm for 1 minute      
                          iodine:    25 ppm for 1 minute                 
                                                                         
   9. Machine       see NSF standards                                   
      method:         (National Sanitation Foundation)                   
                                                                         
          wash:     140-160 deg. F                                       
                                                                         
          rinse:    180 deg F,  10 seconds,  15-25 psi (water pressure) 
                    or chlorine rinse  (50 ppm)                       
 
 

Test your knowledge with a: quiz

For more information,  try:   food safety