Download
1 / 16
160 likes | 219 Views
Control Measures. Control Measures. Focus on safety and quality Food safety control measures -- prevent foodborne illness. Food quality control measures -- maximize shelf-life, slow spoilage, or produce a new product. Processors use a combination of controls
E N D
Control Measures • Focus on safety and quality • Food safety control measures -- prevent foodborne illness. • Food quality control measures -- maximize shelf-life, slow spoilage, or produce a new product. • Processors use a combination of controls • One-control system can be harsh making food unacceptable to the consumer. • Multiple controls is called the hurdle concept and is commonly used. C 5.01 -- Control Measures
Hurdle Concept • Food processors use a combination of control measures called hurdle concept. • The three primary control measures are: • Controlling water activity and/or pH values of the food. • Adding chemicals, such as additives or substances like salt, directly to the food. • Adjusting the atmosphere surrounding the food using special packaging methods. C 5.01 -- Control Measures
1a -- Controlling Water Activity • Water activity (Aw) • Minimum, optimum, and maximum values • Yeasts and mold grow at a lower water activity than do bacteria. • 0.85 safe cutoff for pathogen growth • Based on minimum water activity needed for S. aureus toxin production. C 5.01 -- Control Measures
Water activity and foods C 5.01 -- Control Measures
Controlling water activity C 5.01 -- Control Measures
1b -- Controlling pH • Minimum, optimum, and maximum pH values for microbial growth • Yeasts and mold grow at low pH. • Pathogenic bacteria do not grow at 4.6 or below. • pH controls growth and is not a method to kill pathogens. C 5.01 -- Control Measures
Ways to Control pH • Acidification • direct addition of acid to a low-acid food • Use organic acids, acetic, lactic, or citric or add high-acid food to mixture • Direct – predetermined amounts of acids added to individual finished product • Bath – acid and food combined in large batches and allowed to equilibrate. • Fermentation • Lactic acid bacteria produces lactic acid. C 5.01 -- Control Measures
Measuring pH • pH meter • Digital method but expensive • Easy, the MOST accurate, and sanitary • Indicator solutions • Organic dyes used with dropper • Solution turns pink or red in acid; green or blue in base • Neutral solution may turn lilac and might be difficult to read • Not totally accurate • Indicator paper • Used by dipping • Turns yellow to red in acids; turns green or blue in bases • Easy but not completely accurate • Titration • Add base with know ph to an acid • Uses burette • Difficult to calculate math so recommended for those with chemistry knowledge C 5.01 -- Control Measures
2 -- Adding Chemicals • Preservation method might not prevent growth of all microorganisms. • Add chemical preservatives, such as: • sorbates • benzoates • sulfites • nitrites • antibiotics C 5.01 -- Control Measures
How Chemicals Function? • Denature proteins. • Inhibit enzymes. • Alter or destroy cell walls. • Alter or destroy cell membranes. C 5.01 -- Control Measures
Common Chemical Preservatives C 5.01 -- Control Measures
Regulating Preservatives • Chemical preservatives are food additives. • Approved uses and use levels in FDA’s Food Additive Status List. • Addressed through product formulation. • Processor must carefully control the quantity of food additive for each batch. • Processing conditions must be scientifically established and followed C 5.01 -- Control Measures
3 -- Adjusting the Atmosphere • Packaging does not control the growth of pathogens, it is limited to the control of spoilage microorganisms. • Two functions: • Prevents contamination of the food and/or • Extends the effectiveness of food preservation methods. C 5.01 -- Control Measures
Types of Packaging • Reduced Oxygen Packaging (ROP) – prevents growth of microorganisms to extend shelf-life • Vacuum Packaging – air mechanically removed from the package before sealing • Modified Atmosphere Packaging – flush with nitrogen, carbon dioxide, and/or oxygen before sealing. • Controlled Atmosphere Packaging – retain atmosphere throughout shelf-life using an oxygen scavenger in packaging. C 5.01 -- Control Measures
Packaging – Key Concerns • If ROP used, must have barrier to C. botulinum. • Barriers include: • Water activity below 0.93 with refrigeration • pH below 4.6; salt above 10% • High levels of competing microorganisms • Thermal processing in final container • Freezing with frozen storage and distribution C 5.01 -- Control Measures
