trabalho completo - 52ª Reunião Anual da Sociedade Brasileira de

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trabalho completo - 52ª Reunião Anual da Sociedade Brasileira de
52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Coloração da gordura de ovinos ingerindo dietas contendo bixina 1
Wellington Bizarria dos Santos2, Eldânia Soares Ferreira3, Diana Vieira Rocha4, Francisco Fernando Ramos de
Carvalho5, Dorgival Morais de Lima Júnior6, Kleber Régis Santoro7, Omer Cavalcanti de Almeida7
1
Parte da Dissertação de mestrado da segunda autora
Graduando em Zootecnia, UFRPE/UAG, Garanhuns-PE, Brasil. e-mail: [email protected]
3
Pós-Graduanda em Ciência Animal e Pastagens, UFRPE/UAG, Garanhuns - PE, Brasil. Bolsista CAPES
4
Mestre em Ciência Animal e Pastagens, UFRPE/UAG, Garanhuns - PE, Brasil.
5
Professor adjunto, UFRPE/SEDE, Recife - PE, Brasil
6
Professor adjunto, UFAL, Arapiraca - AL, Brasil
7
Professor adjunto, UFRPE/UAG, Garanhuns - PE, Brasil
2
Resumo: A cor de produtos cárneos é a característica analisada em primeira instância pelos consumidores, sendo
fator determinante para sua aceitação, uma vez que certos espectros de cor remetem a padrões de deterioração e de
idade avançada do animal. Dentre os fatores que compõem a cor destes produtos, a coloração da gordura desempenha
influência marcante, especialmente, naquelas oriundas de animais que ingerem dietas ricas em carotenoides, pois,
devido à sua característica lipossolúvel, tendem a se concentrar em maior quantidade nos adipócitos e, como
consequência, alterações mais pronunciadas na cor. Portanto, o objetivo do presente estudo foi avaliar o efeito da
ingestão de dietas contendo bixina, principal pigmento da semente do urucum, sobre a coloração da gordura de ovinos.
Foram utilizados 32 animais sem padrão de raça definida – SPRD, com peso inicial de 23,17 ± 1,45 kg, distribuídos
em bloco casualizado de acordo com o peso, alocados em baias individuais e submetidos aos seguintes tratamentos:
(T1) dieta sem inclusão de bixina, (T2) dieta com 0,056 g/kg de bixina, (T3) dieta com 0,113 g/kg e (T4) dieta com
0,169 g/kg da matéria seca da dieta. Para a determinação da coloração foram capturadas três imagens de cortes
transversais de cada lombo (com espessura de 1 cm), com a utilização do sistema de visão computacional (SVC) para
determinação das coordenadas CIE (L*a*b*). Os resultados permitem concluir que a ingestão da bixina, nos níveis
utilizados, não promoveu alteração na coloração da gordura.
Palavras–chave: Carotenoides, cor da carne, pigmento, visão computacional
Effect of ingestion of bixin on the colorimetric determination of fat in sheep
Abstract: The color of meat products is the characteristic analyzed in the first instance by the consumers, being a
determining factor in their acceptance, once that certain spectra of color refer to patterns of deterioration and advanced
age of animal. Among the factors that make up the color of these products, the color of the fat plays outstanding
influence, especially those from animals that eat diets rich in carotenoids; due to its lip solubility, the carotenoids tend
to concentrate in greater quantity in adipocytes and, as a result, cause more pronounced changes in color. The
objective of this study is to evaluate the effect of ingestion of diets containing bixin, main pigment of the seed of the
annatto, on the color of the fat of sheep. We used 32 animals non-defined breeds - SPRD, with initial weight of 23.17
± 1.45 kg, distributed in randomized block in accordance with the weight, allocated to individual stalls and subjected
to the following treatments: (T1) diet without inclusion of bixin, (T2) diet with 0.056 g/kg of bixin, (T3) diet with
0.113 g/kg and (T4) diet with 0.169 g/kg of dry matter in the diet. The color was determined by three images of crosssections of each loin (with a thickness of 1 cm), with the use of a computational vision system (CVS) for determination
of the coordinates CIE (L*a*b*). The results allow us to conclude that the ingestion of bixin, at the levels used here,
did not alter the color of the fat.
Keywords: Carotenoids, computer vision, meat color, pigment
Introduction
The impacts provided by staining of meat in marketing of foods reverberate in acceptance or rejection of
certain products. The use of diets rich in carotenoids in animal feed can promote significant colorimetric changes in
the composition of their food. This is due to the fixing of the carotenoid in living tissues, changing their visual
properties that are associated with the physical nature of the molecules. Currently, studies related to the use the
carotenoid bixin (Bixa orellana L., Bixaceae), that exhibits antioxidant properties and consequent minimization of
oxidative processes, directly reflecting on the quality of the food produced, preserving its nutraceutical properties.
The lamb meat is a food appreciated worldwide; its organoleptic characteristics meet the specific audiences,
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
especially when correlating the coloring. Thus, it is well known that the organoleptic characteristics exert a strong
influence on the consumer, therefore, their perception is easily evidenced, even when there is no physical contact.
This, it is notorious assess the dynamics of these carotenoids in the fat of sheep.
Material e Methods
The experiment was carried out in the Sector of Goat of Universidade Federal Rural de Pernambuco (UFRPE),
Recife. We used 32 animals non-defined breeds – SPRD, with initial weight of 23.17 ± 1.45 kg, distributed in
randomized block in accordance to the weight, allocated to individual stalls and subjected to the following treatments:
(T1) diet without inclusion of bixin, (T2) diet with 0.056 g/kg of bixin, (T3) diet with 0.113 g/kg and (T4) diet with
0.169 g/kg of dry matter in the diet (Table 1).
Table 1. Proportion of ingredients and chemical composition (g/kg) of experimental diets.
Ingredient
Treatments (levels of bixin g/kg)
0
0,056
0,113
Tifton 85 hay
550
550
550
Corn grain
300
222
128
Soymeal
130
108
102
REC1
0
100
200
Urea
10
10
10
Mineral Salt
10
10
10
Total
1000
1000
1000
Chemical Composition
MS2
882,5
876,7
870,9
Bixin3
0 0,0
0,056
0,113
PB3
154,0
151,2
154,6
EE3
27,8
32,2
36,0
FDN3
485,2
515,5
546,1
1
Residue from the extraction of colorific (REC); 2g/kg of natural material; 3g/kg of dry matter.
0,169
550
41
89
300
10
10
1000
865,2
0,169
155,3
40,0
576,6
After 58 days of confinement the animals were slaughtered and the carcasses were chilled at 4ºC for 24 hours, when
it was obtained the loins between the 1st and 6th lumbar vertebrae, vacuum packed in polyethylene bags of high
resistance and frozen in a freezer at -18ºC. For the colorimetric determination of fat, images of three cross-sections
of each fillet (with a thickness of 1 cm) were captured using a Computational Vision System (CVS), composed of
box in rectangular (50x50x60cm) with black interior matte and lighting system consisting of two fluorescent lamps
D65 (6500k), attached to the top of the camera at an angle of 45 ° in relation to the plane of the sample. The camera
used in the capture of the images was a Logitech HD Pro Webcam C920 - 15 megapixel Full HD 1080p (1920 x 1080
pixels), located at the top of the camera, in a centralized manner and with a distance of 25 cm from the sample
(Afshari-Jouybari & H. Farahnaky, 2011). The images were processed using the format of ADOBE RGB (1998) and
the software Photoshop CS6.0 for reading the spectrum of visible light, through the coordinates CIE (L*a*b*), where
L * represents the brightness with the light spectrum variant of black to white (0 to 100); the * is the chromaticity
green / red (-120 to 120) and b * is the chromaticity blue / yellow (-120 to 120). The color parameters were estimated
in three specific areas with 25x25 pixels in each slice. The statistical analyzes were performed using the procedure
PROC NPAR1WAY of SAS (Statistical Analysis System, version 9.2.).
Results and Discussion
The results indicate that the inclusion of levels of bixin in diets (0.056, 0.113 0.169 g/kg) did not alter the
coloring of fat from sheep meat (P>0.05), since the parameters of light [L*], proportion red [A*] and proportion
yellow [b*] were not affected by the treatments (P>0.05). The values for the color of the fat in the loin are presented
in (Table 2). The lack of effect of ingestion of bixin on the coloring of the fat of the animals can be explained by
studies of PRACHE et al. (2006) who concluded that the species has limited ability to deposit these pigments in
adipocytes. Additionally, carotenoids are deposited primarily in muscle tissue, which would propitiate meat with
more intense red, except the lutein, which is retained in considerable quantity in the adipose. This feature is interesting
because fat with intense yellowish color refers to animals with increased age, resulted of low enzymatic activity of
xanthophylls oxidases in older animals (Lawrie, 2005). The characteristic of retaining carotenoids in muscle tissue
may be a tool to protect the meat oxidative deterioration, once these pigments have high antioxidant activity, as
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
observed by SANTOS, et al. (2014). Such protection was observed by ROCHA (2013) that observed a greater life of
frozen meat of sheep that ingested bixin, in addition to observing that the protection was dose-dependent.
Table 2. Average values of the color of the fat in the Longissimus dorsi.
Variable
T1
T2
T3
T4
L*
99,68
99,63
99,25
99,57
a*
0,06
0,08
0,11
0,37
b*
0,75
1,17
1,71
1,81
Conclusions
The inclusion of bixin in the diets of sheep did not change the sheep fat color.
Acknowledgements
We thank the National Council for Scientific and Technological Development (CNPq) and the Coordination
for the Improvement of Higher Education Personnel (CAPES), by financial support and by grants.
References
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