title: Dehydration of pollock skin prior to gelatin production.
abstract: Alaska pollock (Theragra chalcogramma) is the U.S.A.'s largest commercial fishery, with an annual catch of over 1 million tons. During pollock processing, the skins are discarded or made into fish meal, despite their value for gelatin production. The absence of gelatin-processing facilities in Alaska necessitates drying of the skins before transport to decrease the moisture content, but conventional hot-air drying is expensive. This study evaluated a less energy-intensive technology, the use of desiccants for reducing water weight in pollock skins prior to shipment. To ensure that the functional properties of gelatin obtained from dried pollock skins were not affected during desiccation, gelatins were prepared from each skin-drying treatment and compared with gelatin extracted from air-dried pollock skins. None of the desiccation treatments decreased the gel strength of pollock skin gelatin, nor were there major differences in gelling temperature or viscosity among the gelatin solutions. This suggests that pollock skins can be economically stabilized for transport to a gelatin-processing facility through the use of regenerable desiccants that are already common in the food industry.
  
  
  CONCLUSIONS
  Pollock skins destined for gelatin production can be stabilized using chemical desiccants prior to shipment. The dehydration process does not harm the functional properties of gelatin, such as gel strength, gelling temperature, and viscosity. This research suggests that fish skins can be economically stabilized for transport to a gelatin-processing facility through the use of regenerable desiccants that are already common in the food industry.
authors.affiliation: USDA Agricultural Research Service, Subarctic Agricultural Research Unit, Fairbanks, AK 99775-7200, USA. Cindy.Bower@ars.usda.gov
authors.forename: Cindy K
authors.initials: CK
authors.lastname: Bower
authors.forename: Roberto J
authors.initials: RJ
authors.lastname: Avena-Bustillos
authors.forename: Katie A
authors.initials: KA
authors.lastname: Hietala
authors.forename: Cristina
authors.initials: C
authors.lastname: Bilbao-Sainz
authors.forename: Carl W
authors.initials: CW
authors.lastname: Olsen
authors.forename: Tara H
authors.initials: TH
authors.lastname: McHugh
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D003890:Desiccation / Q000379:methods*; D055119:Elastic Modulus; D005511:Food Handling / Q000379:methods; D005524:Food Technology; D048388:Gadiformes; D005780:Gelatin / Q000737:chemistry / Q000302:isolation & purification*; D005782:Gels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis* / Q000191:economics; D008970:Molecular Weight; D011786:Quality Control; D012867:Skin / Q000737:chemistry*; D013053:Spectrophotometry; D013718:Tensile Strength; D044366:Transition Temperature; D014783:Viscosity; D014867:Water / Q000032:analysis
chemical_list: D000596:Amino Acids; D005782:Gels; D007220:Industrial Waste; D014867:Water; D005780:Gelatin