reason for autolysis in foods

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M.SohailNational Institute of Food Science & Technology,University of Agriculture, Faisalabad,Pakistan.

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What is Autolysis?What is Autolysis?

• Derivation of word ‘Autolysis’Derivation of word ‘Autolysis’

• Definition of ‘Autolysis’Definition of ‘Autolysis’

• Autolysis in generalAutolysis in general

• Autolysis in food systemsAutolysis in food systems

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AutolysisAutolysis

• Common understanding of autolysisCommon understanding of autolysis

• Autolysis in animal physiologyAutolysis in animal physiology

a) Embryonic development a) Embryonic development

b) Digestion and absorption b) Digestion and absorption

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Autolysis in plantsAutolysis in plants

• Bulbs provide a good mean of Bulbs provide a good mean of understanding autolysisunderstanding autolysis

• Stored food is utilized by the process Stored food is utilized by the process of autolysisof autolysis

• Rose cutting and seedlings are other Rose cutting and seedlings are other examplesexamples

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Autolysis in fruitsAutolysis in fruits

• Browning of apple Browning of apple

• Softening of bananaSoftening of banana

• Flaccid texture of strawberriesFlaccid texture of strawberries

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Autolysis in applesAutolysis in apples

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Autolysis in BananaAutolysis in Banana

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Reason of AutolysisReason of Autolysis

1)1) The main reason are autolytic The main reason are autolytic enzymesenzymes

1)1) Oxidation also plays vital roleOxidation also plays vital role

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Autolytic EnzymesAutolytic Enzymes

• What are autolytic enzymesWhat are autolytic enzymes• Oxidases and peroxidases Oxidases and peroxidases • Enzymes are indispensible for the Enzymes are indispensible for the

growth of bacteriagrowth of bacteria• Streptococcus and Bacillus spp release Streptococcus and Bacillus spp release lytic enzymeslytic enzymes• Molds also produce very active lytic Molds also produce very active lytic

enzymesenzymes

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List of Autolytic enzymesList of Autolytic enzymes

• Amylolytic enzymesAmylolytic enzymes

• Cellulytic enzymes Cellulytic enzymes

• Lipolytic enzymes Lipolytic enzymes

• Pectic enzymes Pectic enzymes

• Lipooxygenase Lipooxygenase

• Polyphenol oxidase Polyphenol oxidase

• Glucose oxidaseGlucose oxidase

• Catalase Catalase

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Role of Oxidation in Autolysis – Role of Oxidation in Autolysis – An ExampleAn Example

• OxidationOxidation

• Apples contain tyrosinase that react with OApples contain tyrosinase that react with O22

• Autolysis can be delayed by:Autolysis can be delayed by:

a) Deactivation of enzymesa) Deactivation of enzymes

b) Lowering of pHb) Lowering of pH

c) Reducing the amount of Oc) Reducing the amount of O22

d) Cutlery free of corrosiond) Cutlery free of corrosion

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