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23 Cards in this Set
- Front
- Back
Indicatewhy the FDA has established DALs. |
- Reflect current max levels for natural or unavoidable defects in food for humans who use that present no health hazard - Reflects max levels considered unavoidable under good manufacturing practice - It's virtually impossible to have plant and animal materials free of various forms of contaminants as materials are stored, handled and transported |
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Explainwhy practicing cGMPs has no impact on DALs. |
Because DALs are established for unavoidable filth that will occur irrespective of what we do, it is inherent property of our harvesting and processing foods |
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List three majorreasons for conducting analysis for extraneous matter in foods. |
- To ensure protection of consuming public from harmful or filthy food products - To meet regulatory requirements of the FD&C - To comply with defect action levels |
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What two resources provide methods forseparating extraneous matter from cereal grains and their products? |
AOAC AACC |
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There are several basic principlesinvolved in separating (isolating) extraneous matter from foods. List five of these principles and give anexample of each principle. |
Density - Sedimentation method to measure heavy filth in shelled nuts Affinity for oleophilic solvents - Cracking flotation method to measure insect infestation of wheat Particle size - Sieving method to remove foreign matter in spices and condiments Diagnostic characteristics for identification of filth - Characteristics of molds, insect fragments grain Chemical identification of contaminants - Animal urine and excrement |
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Briefly describe the major constraint(s)to currently accepted methods for analyses of extraneous matter in foods. |
- Methods can be quite subjective; requires experienced analyst - Multiple steps in procedures makes being quantitative difficult - Fragment counts don't reflect total contaminant biomass present |
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Explain how some of the more recent analytical techniques can assist in identifying sources of extraneous matter in foods |
-X ray is used to inspect wheat for internal infestation - Uric acid measures bird or insect contamination - Microscopy techniques can be used to determine the nature of metals present in foods |
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BODPrinciple - |
- Measure amount of O2 required by MOs to oxidize biodegradable organic constituents present in water and waste - Based on direct relationship between concentration of organic matter and amount of O2 used to oxidize the pollutants and inorganic nitrogenous compounds |
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BODProcedure- |
- Put water sample that has been seeded w/ appropriate MOs in air tight BOD bottle - Measure initial dissolved oxygen immediately - Incubate sample at 20 C for 5 days, measure oxygen again |
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BOD what it stands for |
Biochemical Oxygen Demand |
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CODPrinciple - |
- Organic compounds are destroyed by refluxing in strong acid solution w/ a known quantity of an oxidized agent - Excess potassium dicromate that remains after digestion of organic matter is measured - Amount of organic matter that is chemically oxidizable is directly proportional to amount of potassium dichromate consumed |
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CODProcedure - |
- Reflux known amount of water or wastewater at high temp for 2 hours, w/ known amounts of potassium dichromate and sulfuric acid - Titrate excess potassium dichromate w/ standard ferrous ammounium sulfate solution using orthophenanthroline ferrous complex as an indicator - Caculate COD value w/ equation given |
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COD what it stands for |
Chemical Oxygen Demand |
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Inwhat case would they be instructed to use mercuric sulfate in the COD assay? |
Use mercuric sulfate if hig chloride levels in sample |
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BODAdvantages - |
-Less expensive -No interference - Truly measured dissolved oxygen lost |
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BOD Disadvantages - |
- Slower - Gives low values if poor seed material - Lower precision |
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Higher or lower COD: Poor seed material in BOD test |
COD higher |
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Higher or lower COD: Samplecontains toxic materials |
COD higher |
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Higher or lower COD: Samplehigh in aromatics and nitrogenous compounds |
BOD higher |
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Higher or lower COD: Samplehigh in nitrites and ferrous iron |
COD higher |
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Higher or lower COD: Samplehigh in cellulose and lignin |
COD higher |
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COD Advantages |
- Faster - Better precision |
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COD Disadvantages |
- More expensive - Not truly measuring dissolved oxygen - Interference from some compounds |