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Liquid Smoke as a Preservative for Fresh Water Fish

S.L.R. JayanayakeAG/11/FT/010

Seminar in Food Science and Technology

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Historical background Introduction to fresh water fish Smoke curing Liquid smoke Preservative activity Sensory Attributes Advantages and disadvantages Conclusions

Content

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Fire place of cave men

Stored meat and fish

Good flavor

Long shelf life

History of Smoking

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Lives in

Low salinity waters

Rivers, reservoirs, lakes and ponds

Commonly

Carps, trout, tilapia and eels

Local varieties

Fresh Water Fish

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Highly perishable 75% moisture Rich in nutrients Desirable pH for microbes

Seasonal excessive production

Why Should be Preserved

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Flavoring ,cooking and preservingby exposing to smoke.

Pre treatments ◦ Gutting ◦ Salting

Post treatments◦ Drying ◦ Packaging

Smoke Curing

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Two phases 1. Particle phase2. Vapor phase

Main compounds◦ Alkyl esters◦ Carboxylic acids◦ Polycyclic Aromatic Hydrocarbons (PAH)◦ Phenolic compounds◦ Resin acids and terpenoids ◦ Alkanes, alkenes and other aromatic compounds

Composition of Wood Smoke

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PAHs are potentially carcinogenic

Safety problems

Sanitation problems

Problems in process control

Uneven treatment

Problems of Using Direct Wood Smoke

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Production

Liquid Smoke

Wood Smoke

Extraction or Distillation

Condensation

Separation of Hazardous Compounds

Liquid Smoke

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Antimicrobial activity◦ Phenolic compounds ◦ Carbonyls ◦ Organic acids

Antioxidant activity◦ Phenolic compounds◦ Hydroquinone◦ Formic, benzoic and salicylic acids

Preservation

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Smoke flavorings◦ Carboxylic acids◦ Carbonyl compounds o Sweeto Flowery and fruity aromas

◦ Phenolic compounds o Smokey o Spicy flavors

Color

Sensory Attributes

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Advantages and Disadvantages

Advantages Disadvantages

Low health risks

No need to generate smoke in

fish processing plant

Easy to control process

Only liquid smoke is not

sufficient to preserve fish

Dryers are needed

Cost of production may be high

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Liquid smoke can be used with hurdle concept.

Produce good quality fish preserves with acceptable

sensory properties.

Conclusions

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Thank You