Better inner quality of commercial eggs, compared
to fertilized eggs, stored in room temperature during
different periods.
Souza, R.A.2*, Borba, H.1, Mello, J.L.M.1, Pizzolante, C. C.2, Souza, P.A.1, Ferrari, F.B.1,
Paschoalin, G. C.2
1
Faculty of Agriculture and Veterinary Sciences, Department of Technology, São Paulo State
University, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900, Jaboticabal/SP, Brazil.
2
Animal Science Institute, Nova Odessa, São Paulo, Brazil
*[email protected]
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The aim of this study was to evaluate the inner quality of commercial eggs (unfertilized laying
hens), fertilized eggs of laying breeders and fertilized eggs of broiler breeders, submitted to
different storage periods. 216 red eggs of 40 weeks old were used, being 72 eggs of laying hens
(Isa Brown), 72 fertilized eggs of laying breeders Hy-Line W36 and 72 fertilized eggs of broiler
breeders Cobb. It was used a 3x5 factorial arrangement (tree kind of eggs and five storage
periods) with 12 repetitions for the physical characteristics. The evaluated parameters in these
periods (0, 7, 14, 21 and 28 days) were: eggs weight, Haugh unit and yolk index. The commercial
eggs present, initially (0 day), better inner quality (greater values for yolk index and Haugh unit)
and lower quality losses during the storage period, as well as the weight loss is lower in these
eggs than the others during the same periods.
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Keywords: breeders, inner, laying hen, lineage
Introduction
The main objective in producing eggs for human consumption is to supply the consumer Market
with products that present good quality. In order to keep de nutritional and technological
characteristics, it is necessary, after the laying, to keep the temperature under suitable conditions
reducing, the maximum loses during the storage. Under the regulations of Industrial and Sanitary
Inspection of Animal Products in Brazil (RIISPOA, 1990), “the condemned egg by the hatchery” is a
fertilized egg that is excluded on the hatch process, classified infertile or any other way that not allows
the egg hatcher and can’t be sent to the storage factory or warehousing eggs. However, with the
market changing, may occur the commercialization of these eggs destined to the chicks’ production,
called “roostered egg” or simply fertilized egg. But, the consumer shall take especial cares because
these kinds of eggs lose inner quality very quickly by being more sensible to temperature variations;
so they must be maintained under cooling conditions. Thus, was aimed to evaluate the influences of
different periods of storage upon the inner quality of laying hens’ commercial eggs and fertilized eggs
of laying and broiler breeders.
Materials and methods
This study was developed in Laboratory of Animal Products Technology in Sao Paulo State
University – UNESP, Campus of Jaboticabal, Sao Paulo, Brazil.
It was used 216 red eggs from three birds’ lineages with about 40 weeks of age. So, were used 72
eggs from commercial laying hens Isa Brown strain, 72 fertilized eggs from laying breeders Hy-Line
W36 and 72 eggs from broiler breeders Cobb. The eggs were storage in room temperature about 22,9º
± 2,5ºC and relative humidity about 74,7%. The evaluated characteristics were: egg weight, Haugh
unit, yolk index and storage weight loss. Haugh unit was determined by the method described by Card
& Nesheim (1978) using the formula UH=100l0g(H+7,57-1,71,7W0,37) that H=albumen height e W=
egg weight. The yolk index were determined by the formula YI=YH/YW that YH=yolk height and
YW=yolk width. It was used factorial 3X5 design (three kinds and five storage periods – 0, 7, 14, 21
and 28) with 12 repetitions. Data were submitted to analysis of variance and means compared by
Tukey test (5%) using the statistical program SAS (2002).
Results and discussion
The greater eggs weight were from broiler breeders (BBE – p<0,01), consecutive for the laying
breeders eggs (LBE) and commercial laying hens (CLH). BBE and CLH presented lower values that
those found by Produman (2004) that relates BBE must have the average weight 65g comparing to
CLH 58g because broilers are bigger end heavier than laying hens..
Tables 2 and 3 are the data of the outspread for Haugh unit and yolk index. It is observed that
Haugh unit was significantly greater for CLH on the beginning (90.87) followed by BBE and LBE;
however, after 28 days it is observed the quality wasn’t different between the egg types. According to
USDA (2006) classification for albumen, the dense must present UH higher than 72, the medium
density between 72 and 60 and lower density below 60. So, in this sense, the obtained results to HU
for CLH and BBE are in the recommended range.
Table 1. Means for Egg Weight (EW), Haugh unit (HU) and yolk index (YI) in diferente periods
of storage and egg types.
EW (g)
CLH
LBE
BBE
DMS
F test
54,33c
55,82b
63,05a
1,18
174.86**
0
7
14
21
28
DMS
F test
Int. TxP
CV %
59,39a
58,64a
57,70ab
56,77b
56,17b
1,77
8,37**
0,07ns
4,73
HU
Egg Type (T)
46,25
43,45
40,00
2,82
13,83**
Storage Period - days (P)
78,76
52,51
32,99
26,96
24,94
4,24
434,03**
9,07**
15,09
YI
0,369
0,295
0,321
0,01
117,52**
0,46
0,37
0,30
0,27
0,24
0,019
294,16**
3,32**
9,26
Averages followed by distinct letters (columns) differ according to Tukey’s test (p<0.05).
Yolk index (table 2) was significantly greater to CE on the 0 day when compared to BBE e
LBE, the same occurred during all the storage periods except on 7 days of storage that the obtained
values weren’t different from LBE. According to Souza (1997), the medium values for yolk index for
fresh eggs must be between 0.42 and 0.40; so the medium values obtained for YI (BBE and LBE) are
between the described by the author.
Table 2. Means of Haugh Unit (HU) for the outspread egg types and storage periods
Egg Type
CLH
LBE
BBE
0
90,87Aa
69,53Ac
77,29Ab
HU
Storage Periods (days)
7
14
53,30Ba
31,04Cb
53,82Ba
39,34Ca
43,92Bb
29,35Cb
21
29,02CDa
32,28Da
20,74Db
28
25,49Da
24,16Ea
22,43Da
Averages followed by distinct letters (columns - lowercase) differ according to Tukey’s test (p<0.05). Averages followed by
distinct letters (lines – capital letters) differ according to Tukey’s test (p<0.05 (p<0,05).
Table 3. Means of Yolk Index (YI) for the outspread egg types and storage periods.
Egg type
CLH
LBE
BBE
0
0,51Aa
0,42Ab
0,44Ab
YI
Storage Periods (days)
7
14
0,40Ba
0,35Ca
0,32Bb
0,27Cb
0,39Ba
0,30Cb
21
0,31CDa
0,25CDb
0,25Db
28
0,27Da
0,22Db
0,22Db
Averages followed by distinct letters (columns - lowercase) differ according to Tukey’s test (p<0.05). Averages followed by
distinct letters (lines – capital letters) differ according to Tukey’s test (p<0.05 (p<0,05).
Conclusions
Under the conditions that the study was carried out, it is concluded that the initial quality of
fertilized eggs is lower than the commercial and the storage in room temperature has a big influence in
the inner quality of the eggs.
References
CARD, L.E., NESHEIM, M.C. (1978). Producion avicola. Zaragoza: Editoral Acribia.
PROUDMAN, J. A. (2004). Reprodução Animal. 7.ed. Kiawah Island, p.242-257.
RIISPOA. 1990. Regulamento da Inspeção Industrial e Sanitária de Produtos de Origem Animal.
Portaria n0 01 de 1990.
SAS Institute. (2002). SAS user’s guide: statistics. Release 9.1. Cary.
SOUZA, P.A. (1997). Efeito da idade da galinha na qualidade dos ovos mantidos sob condições de
ambiente. Ciência e Tecnologia de Alimentos. Campinas, v.17, n.1, p.49-52.
USDA (2008). United States Departament of Agriculture. Egg grading manual.