FISH DRYING APPLICATION NOTE

DEDICATED DRYING MACHINES MANUFACTURERDEHYDRATION OF FISHBEFORE DEHYDRATION AFTER DEHYDRATION Drying MethodsAir or Contact DryingDrying heat is transferred to fish from heated air or from a heated surface which utilizes the airmovement above the fish to remove the moisture away from it.Vacuum DryingVacuum drying has its advantage and is having its application in greater evaporation rate ofwater form fish at reduced pressure. This drying is achieved at lower temperatures and utilizesthe process of conduction by contact with heated surface.Freeze DryingThe process of freeze drying operates on the principle of sublimation to evaporate vapoursdirectly from the solid phase (ice).Dedicated Analytical SolutionsCorporate Office Tel +91-9643480893 Application LabKDM Analytical +91-9540666954 D-198, Mundka Industrial AreaB-2/41 First Floor, Rohini Delhi-110081Sector-16, Delhi-110089 Fax +91- 22612722 web www.kdmanalytical.comIndia E-mail [email protected]

DEDICATED DRYING MACHINES MANUFACTURERSaltingSalting is the preservation of food with dry edible salt. It is related to pickling (preparing foodwith brine, i.e. salty water). It is one of the oldest methods of preserving food, and twohistorically significant salt-cured foods are dried and salted cod. Four types of salting methodsare employed namely  Brining  Pickling  Kench curing  Gaspe curingSmokingSmoking is a fish preservation technique as old as drying and salting. The smoke from wood isused to partially dehydrate and preserve fish in smoking process. The peculiar smell and odordistinguish smoked products and creates a special market. Depending on temperature ofsmoking, it is classified as hot and cold smoking. Lot of variations does exist in terms of forms offish to be smoked, smokehouse development and pretreatment for smoking. Though smokedproducts have a special market, the microbiological quality aspect of smoked products has beena controversial subject. A better control and standardization of smoking procedure is desired toobtain safe products.DryingDrying alone or in combination with salting is one of the most practiced, low cost fishpreservation techniques. With technological development and improvement in life style, driedproducts demand is falling in developed world. But, in developing world due to it’s lowprocessing and storage cost, dried fish are preferred. To trap developed world’s market, newertechnologies giving better quality are under focus, though they are costlier than air drying. Fishare generally dried under open sun at atmospheric conditions. Mechanical dryers are developedfor processing fish under controlled and hygienic conditions. These dryers also include solardryers. Freeze, vacuum and heat pump dryers are being used with specific applications givingbetter quality dried fish.Principle of Preservation by DryingMain reason for degradation of fish is microbial growth. The environment for growth ofmicrobes is indicated by moisture content and a better parameter that does so is water activity.To inhibit the growth of microbes water activity should be lower than 0.7. Water activity of 0.6is truly desired but 0.7 values are sufficient for preservation. WE CARE FOR YOUR BUSINESSDedicated Analytical SolutionsCorporate Office Tel +91-9643480893 Application LabKDM Analytical +91-9540666954 D-198, Mundka Industrial AreaB-2/41 First Floor, Rohini Delhi-110081Sector-16, Delhi-110089 Fax +91- 22612722 web www.kdmanalytical.comIndia E-mail [email protected]