PROTEIN INSOLUBILIZATION IN FROZEN GREENLAND HALIBUT ( REINHARDTIUS HIPPOGLOSSOIDES )

PROTEIN INSOLUBILIZATION IN FROZEN GREENLAND HALIBUT ( REINHARDTIUS HIPPOGLOSSOIDES ) Frozen storage of minced Greenland halibut (Reinhardtius hippoglossoides) at ‐10°C resulted in a rapid loss in salt solubility of “my ofibrillar proteins” (approximately 50% in 15 days) and in a gradual loss in water solubility of “sarcoplasmic proteins” (approximately 40% in 120 days). The water and salt inextractable protein from frozen mince (R) was completely soluble in 4% sodium dodecylsulfate (SDS) when a disulfide bond reducing agent such as mercaptoethanol (ME) was present. Other reagents, including urea and Triton X 100, were less effective in solubilizing the protein from mince after frozen storage. Evidence presented supports the thesis that disulfide bond formation contributes to the observed loss in protein extractability during frozen storage of mince. Addition of various thiol reagents to mince prior to freezing was effective in minimizing protein insolubilization. An estimated 50% of the reduced cysteine associated with protein is oxidized in mince after long time storage at ‐10°C. However, the kinetics of disulfide bond formation do not parallel the time course of protein insolubilization; accordingly, the possibility that disulfide bond formation is a secondary event cannot be excluded. Other lines of evidence indicate that additional covalent or strong bond interactions contribute to the formation of(R). Solubilization and boiling of(R) in SDS/ME does not dissociate high molecular weight aggregates (500–1000 Kdaltons) although these aggregates are disrupted by sodium borohydride reduction. In addition, the degree of hydrolysis of proteins in frozen mince by certain proteolytic enzymes is lower then that of fresh mince despite the complete solubilization of the mince protein by these proteolytic enzymes. The mince protein from frozen fish contains substantially more fluorescence than that of fresh fish. Fluorescence is associated with the high molecular weight peptide fraction after pepsin catalyzed hydrolysis. The amino acid composition of mince proteins after HCl or formic acid/HCl hydrolysis did not change appreciably as a result of frozen storage. The data indicate that covalent bond formation by sulfhydryl residues and other borohydride and acid labile linkages contribute to the loss in solubility of the protein in Greenland halibut mince during frozen storage at ‐10°C. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Food Biochemistry Wiley

PROTEIN INSOLUBILIZATION IN FROZEN GREENLAND HALIBUT ( REINHARDTIUS HIPPOGLOSSOIDES )

Journal of Food Biochemistry, Volume 8 (3) – Sep 1, 1984

Loading next page...
 
/lp/wiley/protein-insolubilization-in-frozen-greenland-halibut-reinhardtius-7oBD4OSqqe
Publisher
Wiley
Copyright
Copyright © 1984 Wiley Subscription Services, Inc., A Wiley Company
ISSN
0145-8884
eISSN
1745-4514
DOI
10.1111/j.1745-4514.1984.tb00323.x
Publisher site
See Article on Publisher Site

Abstract

Frozen storage of minced Greenland halibut (Reinhardtius hippoglossoides) at ‐10°C resulted in a rapid loss in salt solubility of “my ofibrillar proteins” (approximately 50% in 15 days) and in a gradual loss in water solubility of “sarcoplasmic proteins” (approximately 40% in 120 days). The water and salt inextractable protein from frozen mince (R) was completely soluble in 4% sodium dodecylsulfate (SDS) when a disulfide bond reducing agent such as mercaptoethanol (ME) was present. Other reagents, including urea and Triton X 100, were less effective in solubilizing the protein from mince after frozen storage. Evidence presented supports the thesis that disulfide bond formation contributes to the observed loss in protein extractability during frozen storage of mince. Addition of various thiol reagents to mince prior to freezing was effective in minimizing protein insolubilization. An estimated 50% of the reduced cysteine associated with protein is oxidized in mince after long time storage at ‐10°C. However, the kinetics of disulfide bond formation do not parallel the time course of protein insolubilization; accordingly, the possibility that disulfide bond formation is a secondary event cannot be excluded. Other lines of evidence indicate that additional covalent or strong bond interactions contribute to the formation of(R). Solubilization and boiling of(R) in SDS/ME does not dissociate high molecular weight aggregates (500–1000 Kdaltons) although these aggregates are disrupted by sodium borohydride reduction. In addition, the degree of hydrolysis of proteins in frozen mince by certain proteolytic enzymes is lower then that of fresh mince despite the complete solubilization of the mince protein by these proteolytic enzymes. The mince protein from frozen fish contains substantially more fluorescence than that of fresh fish. Fluorescence is associated with the high molecular weight peptide fraction after pepsin catalyzed hydrolysis. The amino acid composition of mince proteins after HCl or formic acid/HCl hydrolysis did not change appreciably as a result of frozen storage. The data indicate that covalent bond formation by sulfhydryl residues and other borohydride and acid labile linkages contribute to the loss in solubility of the protein in Greenland halibut mince during frozen storage at ‐10°C.

Journal

Journal of Food BiochemistryWiley

Published: Sep 1, 1984

References

  • Parameters of texture change in processed fish: Cross‐linkage of proteins
    MAO, MAO; STERLING, STERLING

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off