Food Biochemistry and Food Processing (2 edition)

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Fish Gelatin

Soottawat Benjakul, Phanat Kittiphattanabawon, and Joe M. Regenstein

Introduction

Production of Gelatin

Pretreatment of Raw Material

Removal of Noncollagenous Protein

Removal of Fat

Removal of Minerals

Swelling of Pretreated Raw Materials

Acid Process

Alkaline Process

Acid Process in Conjunction with Pepsin

Extraction of gelatin

Drying

Fish Gelatin

Functional Properties of Gelatin

Gelation

Source of Raw Material

Presence of Endogenous Protease in Raw Material

Extraction Conditions

Emulsifying and Foaming Properties

Film formation

Improvement of Functional Properties of Fish Gelatin

Use of protein cross-linkers

Aldehydes

Phenolic Compounds

Genipin

Transglutaminase

Use of hydrocolloids

Oxidation process

Applications of Gelatin

References

Abstract:Fish gelatin, partially hydrolyzed or denatured collagen,

has received attention as the alternative of mammalian and avian

gelatin. It can be extracted from the by-products rich in collagen

such as fish skin, bone, scale, or the skin of some invertebrate,

and so on. Composition and properties of fish gelatin can be gov-

erned by the sources of raw materials. Processing parameters such

as pretreatment, extraction temperature, bleaching, drying, and so

on influence the chemical and functional properties of gelatin. Gen-

erally, fish gelatin exhibited lower functional properties than those

from land animals, thereby limiting the applications of fish gelatin.

Several approaches have been therefore developed to improve the

properties of fish gelatin via modification using chemical or enzy-

matic processes. Therefore, fish gelatin can be applied more widely

in several industries.

INTRODUCTION

Gelatin is biopolymer obtained from partial denaturation of col-

lagen. It has a wide range of applications in food and non-

food (photographic, cosmetic, and pharmaceutical) industries

(Regenstein and Zhou 2007a). Generally, gelatin is obtained

from mammals, especially pig and cow skins and bones.

Recently, outbreaks of mad cow disease (bovine spongi-

form encephalopathy, BSE) have caused anxiety in customers.

Additionally, the gelatin obtained from pigskin and pig bone

cannot be used in Kosher and Halal foods due to religious con-

straints. Furthermore, an increasing attention to health issues by

consumers has also resulted in a high demand of fish gelatin

(Kittiphattanabawon et al. 2010). As a consequence, the al-

ternative sources for gelatin production have been intensively

increased, especially skin, bone, and scale from seafood pro-

cessing by-products due to their abundance and low cost. How-

ever, fish gelatins have limited application, mainly owing to

the lower gel strength and lower gel stability, compared with

those from their mammalian counterparts (Leuenberger 1991).

This chapter covers the literature reviews of gelatin, particu-

larly fish gelatin, regarding their production, functional proper-

ties, and improvement of their functional properties as well as

applications.

Gelatin is one of the commonly used food ingredients, ob-

tained by the thermal denaturation of collagen (Bailey and

Light 1989). The process involves the disruption of noncovalent

Food Biochemistry and Food Processing, Second Edition. Edited by Benjamin K. Simpson, Leo M.L. Nollet, Fidel Toldr ́a, Soottawat Benjakul, Gopinadhan Paliyath and Y.H. Hui.

©C2012 John Wiley & Sons, Inc. Published 2012 by John Wiley & Sons, Inc.

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