Volume 3 • Issue 3 • 1000199
J Nutr Food Sci
ISSN: 2155-9600 JNFS, an open access journal
Open Access Research Article
Iheagwara, J Nutr Food Sci 2013, 3:3
DOI: 10.4172/2155-9600.1000199
*Corresponding author: Marcquin Chibuzo Iheagwara, Department of
Food Science and Technology, Federal University of Technology, Owerri,
PMB 1526 Owerri, Imo State, Nigeria, Tel: +2348032922630; E-mail:
marcquin.iheagwara@futo.edu.ng
Received March 10, 2013; Accepted March 18, 2013; Published March 20, 2013
Citation: Iheagwara MC (2013) Effect of Ginger Extract on Stability and Sensorial
Quality of Smoked Mackerel (Scomber scombrus) Fish. J Nutr Food Sci 3: 199.
doi:10.4172/2155-9600.1000199
Copyright: © 2013 Iheagwara MC, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Effect of Ginger Extract on Stability and Sensorial Quality of Smoked
Mackerel (Scomber scombrus) Fish
Marcquin Chibuzo Iheagwara*
Department of Food Science and Technology, Federal University of Technology, Owerri, Nigeria
Abstract
The effect of ginger extract on the stability and sensorial quality of smoked mackerel fsh stored at 28 ± 2°C was
determined over 20 days. Chemical, microbiological and sensory analyses were performed to investigate quality
changes, and to determine the shelf stability of the products. The proximate, thiobarbituric acid (TBA) value, peroxide
value (PV), mould count, and trimethylamine (TMA) were found statistically signifcant (P ≤ 0.05), in the smoked
mackerel fsh throughout storage. Protein, fat and ash contents of the ginger extract treated samples had marked
% increase compared to the control. The lowest TBA (0.08 mg MDA/kg), peroxide (4.50 mEq/kg) and TMA (3.46
mg N/100 g) values were recorded in 5% ginger extract treated samples, while the highest TBA (1.45 mg MDA/
kg), PV(30.07 mEq/kg) and TMA (15.52 mg N/100 g) occurred in the control. The result also revealed that samples
treated with ginger extract had lower mould count than the control. The organoleptic results showed that samples
treated with 5% ginger extract had the best acceptance, and were signifcantly different (P ≤ 0.05), when compared
to the control after 10 days of storage.
Keywords: Smoked mackerel fsh; Ginger; Stability; Quality; Lipid
oxidation; Tiobarbituric acid; Peroxide; Storage
Introduction
Fish constitutes a very important component of diet for many people,
and ofen provides much needed nutrients for a healthy living. Fish
serves as a principal source of dietary protein, which is very inexpensive
in relation to other protein foods [1]. It is the characteristics of fsh as
a cheap source of animal protein, which is now evident throughout the
world that makes it an excellent component of human diet. Fish protein
now takes precedence over other protein of animal origin, and compares
favorably with that of milk, egg and meat in its amino acid composition.
It is this quality that makes fsh protein to be practically indispensable
to developing countries, such as Nigeria, for diet supplementation,
where the staple diet or food consist primarily of starchy foods [2].
Besides, fsh is known to contain a very high quality of fats and oil,
and fsh fat is very high in polyunsaturated fatty acids, which are very
important in lowering blood cholesterol level. Te fsh oil, on the other
hand, contains the fat soluble vitamins. Fish is also a very good source
of thiamine and ribofavin, and contains minerals, phosphatids sterols,
enzymes, hormones, hydrocarbons and pigments [3,4]. However, fsh is
an extremely perishable food commodity, and hence, is subject to post
harvest losses ranging from bacterial and autolytic spoilage to other
factors. Tese causes cause fsh to lose its organoleptic qualities, and
generally unacceptable for human consumption. It is this perishability
of fsh that makes it to be processed into fsh based products, such as
smoked and canned fsh, fsh cake, fsh meal, fsh burger, etc. [5]. Fish
smoking is one of the traditional methods of preservation of fsh in
Africa. Smoke curing, as applied to fsh, is a method of preservation
efected by combination of drying and the deposition of naturally
produced chemicals, resulting from the thermal breakdown of wood
[6]. Dried fsh spoilage has been characterized by reddening, browning,
or other discoloration mould attack, and development of rancidity.
Te use of synthetic antioxidant has been very efective in controlling
rancidity. However, synthetic antioxidants have frequently been
associated with certain health problems [7]. Tis has necessitated the
use of natural antioxidants, such as spices, in the prevention of rancidity
in smoked fsh [8,9]. Spices (ginger, onion, garlic, etc.) are edible
plant materials that possess anti-oxidant, antiseptic and bateriostatic
properties. Tey are added to foods to delay onset of deterioration, such
as rancidity, and also function as seasonings to foods as well as impart
favor to the foods [10]. Ginger as a spice has a geographical spread that
covers every part of the globe and it is consumed whole as a delicacy,
used in traditional oriental medicine, or as spice in foods, such as fsh
[11-13]. Ginger contains spectra of biologically active compounds,
such as curcumin, 6-gingerol, 6-shagaols, zingiberene, bisabolene and
several other types of lipids that confer on it, the properties of being
pungent and a stimulant. Tese compounds are responsible for the
unique aroma and favour of ginger, and account for about 1-3% of the
weight of fresh ginger [13]. Tis present study is designed to investigate
the efect of ginger extract in improving the stability and organoleptic
quality of smoked mackerel fsh.
Materials and Methods
Materials
Te raw whole mackerel fsh (Scomber scombrus) used for the
study was bought from a cold store in Owerri market, and identifed
at the Department of Fisheries and Aquacultural Technology, Federal
University of Technology, Owerri. Te spice used is extract from ginger
(Zingiber ofcinalae) rhizomes. All chemicals used were of analytical
grade.
Generation of samples
One hundred and eighty (180) fsh samples with weight ranging
from 220-250 g were selected for the study. Each of the raw whole
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ISSN: 2155-9600