Waste Management for Smoking Salmon By-Products to Extract Omega-3
Fish Oil
Tarek Fouda
*
Department of Agricultural Engineering, Faculty of Agriculture, Tanta University, Egypt
*Corresponding author: Tarek Fouda, Department of Agricultural Engineering, Faculty of Agriculture, Tanta University, Egypt, Tel: +20 403317928, E-mail:
tfouda@yahoo.com
Received date: May 25, 2018; Accepted date: August 14, 2018; Published date: August 21, 2018
Copyright: © 2018 Fouda T. 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.
Abstract
The main objective of this research was to investigate the possibility of producing fish oil from smoking salmon
waste by using cold pressing and wet rendering methods. The amount and the characteristics of extracted of oil
were tested. The samples were used about 33.810 kg, smoked fish caused about 9.610 kg. As a Salmon waste
(skin, viscera, backbone frames and cuts off) it's recorded about 20% of the total mass from salmon slices. The
results showed the smoking salmon waste have more than 18% of oil fish per one kg of salmon waste. The oil
weight from Salmon by-products was increased with pressing time increase as well as oil productivity increased. The
oil extraction yield increased and characterization of quality. The optimum conditions at pressing time was 180 min,
oil weight was 93 g.oil/500 g. Salmon by-products, oil productivity was 18.00% and extraction efficiency were
98.46% at constant pressure. The oil weight from Salmon by-products was increased with heating time increase as
well as oil productivity increased. The oil extraction yield increased with the wet rendering processes at heating time
of 60 min have oil weight about 90 g.oil/500 g. Salmon by-products, oil productivity about 18.00% and extraction
efficiency was 95.23%. The oil extraction yield increased with the wet rendering processes and characterization of
the oil increasing with cold pressing processes.
Keywords: Extract; Efciency; Yield; Smoking salmon; Waste; Fish
oil; Cold pressing; Wet rendering
Introduction
Management and processing of fsh by-products and waste is an
environmental, social priority for many countries and is more
problematic because of rising production volumes. Te fsh processing
industry generates large quantities of tissue waste and by-products
which tend to be either discarded or retailed at low value for fertilizer
or animal feed [1]. Te fsh by product is nearly (skin 6%-viscera 7%-
of-cuts 10%-head 18%-backbone frames 10%) [2]. Te fsh processing
industries produce large quantities of fsh waste which ofen represent
about 20% to 50% of the total fsh weight [3]. Waste generated from
fsh processing plants is approximately 50 wt. % of harvested fsh
depending on the type of fsh, product and processing techniques [4].
Laboratory studies shows that green extraction methods provide an
excellent alternative to traditional methods the amount of fsh oil
produced and the quality is similar or even better. However, these
methods require additional research. It is necessary to improve the pre-
processing technology and the process of extraction itself. Fish oil
accounts for about 2% of world consumption of fats and oils.
Traditionally, the fsh oil is obtained as a by-product of the fsh meal
industry but currently smaller fsh with a relatively high fat content-
anchovies, sardines, herring and eels are in the centre of attention as a
raw material in the fsh oil industry. Already historically fsh oil has
played a signifcant role in the human diet and currently, the demand
for fsh oil is still growing thanks to its curative properties [5].
Tere are many methods to extract fsh oil such as wet and dry
rendering, solvent extraction, silage production and supercritical fuid
extraction. Te wet rendering extraction process involved frst cutting
the viscera still frozen into small pieces and putting them in 550 mL
boiling water for 20 minutes. Ten cooling down for 40 minutes and
fltering in a strainer with fast fow rate. Te process was repeated and
afer separation from water, the supernatant was fltered again using a
fne sieve and brought to the fre for 30 minutes [6]. Te optimum
method to process tilapia by-product into fsh oil was by extraction at
70°C for 35 minutes [7]. Te solvent extraction is another process that
yields fsh oil as a by-product. In this process, most of the water and
some or the entire fat are removed using suitable chemical solvents.
Normally, the solvent is recovered in the process and reused. Te
disadvantages of this method are the high cost [8]. Salmon light muscle
had 20.4% protein and 2.1% fats and oils, whereas the salmon dark
muscle contained 17.5% protein, 12.5% fats and oils [9].
Salmon have higher fat content in the viscera than the fllet [10].
Tilapia viscera composition of 14.62% ± 0.79% protein, 10.75% ±
0.97% lipids, 60.44% ± 0.27% moisture and 4.90% ± 0.61% minerals
[11]. Fish oil contains long chain PUFA Polyunsaturated fatty acid
(omega-3), the prominent ones being EPA and DHA making it
attractive edible oil [10]. Fish oil is a very efective nutrient and
contains important omega 3 fatty acids that can be absorbed easily.
Fish oil contains both Docosahexaenoic acid (DHA) and
Eicosapentaenoic acid (EPA) [5]. Tere is evidence from multiple
studies supporting intake of recommended amounts of DHA and EPA
in the form of dietary fsh or fsh oil supplements lowers triglycerides,
reduces the risk of death, heart attack, dangerous abnormal heart
rhythms and strokes [12].
Te fsh oil production although Europe is clearly the largest
producer of by-product fsh oil. Tis is principally because Asia
processes a large volume of farmed shrimp waste which does not yield
any oil. Tis factor is also a major contributor to the percentage of by-
product oil being at 26% globally rather than the 33% for fshmeal [13].
F
i
s
h
e
ri
e
s
a
n
d
A
q
u
a
c
u
l
t
u
r
e
J
o
u
r
n
a
l
ISSN: 2150-3508
Fisheries and Aquaculture Journal
Fouda, Fish Aqua J 2018, 9:3
DOI: 10.4172/2150-3508.1000253
Research Article Open Access
Fish Aqua J, an open access journal
ISSN: 2150-3508
Volume 9 • Issue 3 • 1000253