SUMMARY
Meat tenderness is a major attribute for consumers worldwide. However, few studies investigate the importance of lamb meat tenderness for Brazilian consumers. This study assessed consumers’ evaluation of lamb meat with high shear forces. Eight lambs were slaughtered at 32.5±2.5kg of live weight and 5 to 6 months of age. The Longissimus dorsi muscle from both half carcasses was randomly assigned to four different postmortem processes: Tough Meat (TM), obtained by cold shortening, Fresh Meat (FM), Aging for 3 (A3) and 7 (A7) days postmortem . The variables measured were the sarcomere length, shear force (WBSF) and myofibrillar fragmentation index. We also applied the sensory analysis using affective acceptance tests with hedonic scale of nine points to measure texture, juiciness and overall quality of the meat. The postmortem processing for TM resulted in shorter sarcomere and greater shear values (p <0.05) compared to all other samples, while FM, A3 and A7, did not differ between the samples. Myofibrillar fragmentation was greater for A7 compared to TM (p <0.05), while FM and A3 showed intermediate values that did not differ between the treatments. In the sensory analysis, TM samples received significantly lower scores (p <0.01) for all attributes compared to other treatments and the attributes were not different between the post rigor processes. Consumers identified and evaluated negatively the meat samples with high WBSF. However, further studies are needed to elucidate the impact of smaller differences in WBSF, at intermediate values, on consumers’ evaluation.
Acceptance; Sarcomere length; Shear force; Tenderness
RESUMO
A maciez da carne é um atributo importante para os consumidores do mundo todo. Porém, ainda faltam estudos sobre sua importância na área de carne de cordeiro para consumidores brasileiros. O objetivo do estudo foi verificar a avaliação dos consumidores em relação à carne de cordeiro com força de cisalhamento elevada. Oito cordeiros foram abatidos com 32,5 ± 2,5kg de peso vivo e 5 a 6 meses de idade. O músculo Longissimus dorsi das meias carcaças foi distribuído aleatoriamente em quatro diferentes processamentos postmortem: Carne Endurecida (CE), obtido pelo encurtamento pelo frio, Carne Fresca (CF), maturada por 3 (M3) e 7 (M7) dias postmortem . As variáveis medidas foram comprimento do sarcômero, força de cisalhamento (FC), índice de fragmentação miofibrilar (IFM)e testes sensoriais de aceitação afetiva com escala hedônica de nove pontos para textura, suculência e qualidade global. O processamento postmortem para CE resultou em menor sarcômero e maiores valores de FC (p <0,05) em comparação com outras amostras, enquanto estas não diferiram entre si. O IFM foi maior para M7 em relação à CE (p <0,05), enquanto CF e M3 apresentaram valores intermediários que não diferiram. Noteste sensorial, as amostras de CE receberam escores menores (p <0,01) para todos os atributos comparados aos demais tratamentos, que não diferiram entre si. Os consumidores avaliaram negativamente a carne que apresentou alta FC. Porém, estudos devem ser realizados para elucidar o impacto de diferenças menores, em faixas intermediárias de FC, na avaliação do consumidor.
Aceitação; Comprimento de sarcômero; força de cisalhamento; maciez
INTRODUCTION
Sheep farming in Brazil is increasing, with a growth of 12% of heads between 2004 and 2012 (INSTITUTO FNP, 2014INSTITUTO FNP. ANUALPEC 2014:anuário da pecuária brasileira. 20. ed. São Paulo, 2014. 213p.). The fast farming cycle, with the reproductive life starting at 10 months old and slaughter before 6 months old, has been an important characteristic to boost this growth. The breeding of Santa Inês has gained interest and is increasing, because this breed fits these characteristics well and has high adaptability to several types of environment (FREIRE et al., 2010FREIRE, M.T.A.; NAKAO, M.Y.; GUERRA, C.C.; CARRER, C.C.; SOUZA, S.C.; TRINDADE, M.A. Determinação de parâmetros físico-químicos e de aceitação sensorial da carne de cordeiros proveniente de diferentes tipos raciais. Alimentos e Nutrição Araraquara , v. 21, n. 3, p. 481-486, 2010.).
Despite the increasing herd, production is still not sufficient to supply the Brazilian market (FIRETTI et al., 2010FIRETTI, R.; CARRER, C.D.C.; SILVA, V.L.; TRINDADE, M.A.; SOUZA, S.C.D.; SAVASTANO JR, H.; RIBEIRO, M.M.L.O.The perception of Sao Paulo state consumers in relation to ship meat: analysis by principal components. Revista Brasileira de Saúde e Produção Animal ,v.11, n.1,p.1-13, 2010.; BRASIL, 2015). Moreover, production of lamb meat faces issues mainly because of low product standardization, shortage of continuous supply (FIRETTI et al., 2010FIRETTI, R.; CARRER, C.D.C.; SILVA, V.L.; TRINDADE, M.A.; SOUZA, S.C.D.; SAVASTANO JR, H.; RIBEIRO, M.M.L.O.The perception of Sao Paulo state consumers in relation to ship meat: analysis by principal components. Revista Brasileira de Saúde e Produção Animal ,v.11, n.1,p.1-13, 2010.), and high prices (FIRETTI et al, 2010FIRETTI, R.; CARRER, C.D.C.; SILVA, V.L.; TRINDADE, M.A.; SOUZA, S.C.D.; SAVASTANO JR, H.; RIBEIRO, M.M.L.O.The perception of Sao Paulo state consumers in relation to ship meat: analysis by principal components. Revista Brasileira de Saúde e Produção Animal ,v.11, n.1,p.1-13, 2010.; ANDRADE et al., 2016 ANDRADE , J.C. SOBRAL , L.A. ; ARES , G. ; DELIZA , R. Understanding consumers' perception of lamb meat using free word association . Meat Science , v. 117 , p. 68 - 74 , 2016 ).
Among the organoleptic quality attribute s(color, texture, juiciness and flavor), texture is the most important sensory characteristic for preference and acceptance by consumers, as well as for their decision to purchase (KOOHMARAIE, 1994KOOHMARAIE, M.Muscle proteinases and meat aging. Meat Science ,v.36, n.1-2, p.93-104, 1994.; STARKEY et al., 2015STARKEY, C.P.; GEESINK, G.H.; ODDY, V.H.; HOPKINS, D.L.Explaining the variation in lamb longissimus shear force across and within ageing periods using protein degradation, sarcomere length and collagen characteristics. Meat Science ,v.105, p.32-37, 2015.). Texture perceived by consumers can be measured through sensory methods and is related to shear force measurements (CULLER et al., 1978 CULLER , R.D. ; PARRISH JR , F.C. ; SMITH , G.C. ; CROSS , H.R. Relationship of myofibril fragmentation index to certain chemical, physical and sensory characteristics of bovine Longissimus muscle . Journal of Food Science , v. 43 , n. 4 ,p. 1177 - 1180 , 1978 .). Within sensorial analysis, there are affectionate methods, which demonstrate a product potential through the direct opinion of consumers about specific characteristics (MEILGAARD et al., 1999MEILGAARD, M.; CIVILLE, G.V.; CARR, B.T. Sensory evaluation techniques .New York:CRC Press, 1999. 281p.).
Tenderness is partially defined by the toughening phase that occurs during rigor mortis . Meat toughening is generated by the shortening of sarcomere associated to an increase on shear force and meat toughening may be reverted by aging (WHEELER & KOOHMARAIE, 1994WHEELER, T.L.; KOOHMARAIE, M.Prerigor and postrigor changes in tenderness of ovine longissimus muscle. Journal of Animal Science ,v.72, n.5,p.1232-1238, 1994; KOOHMARAIE et al., 1998)KOOHMARAIE, M., SHACKELFORD, S. D. WHEELER, T.L. Effect or prerigor freezing and postrigor calcium chloride injection on the tenderness of callipygelongissimus. Journal of Animal Science, v.76, n.5, p. 1427-1432, 1998.. Cold shortening is very common in commercial conditions. Animal size associated to lack of fat covering results in fast decrease of the carcass temperature during the cooling (MONIN & SANTÉ-LHOUTELLIER, 2014MONIN, G.; SANTÉ-LHOUTELLIER, V. Conversion of muscle to meat: color and texture deviations. In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences .2ed. Oxford: Elsevier Ltd, 2014. p. 339-345.; OCKERMAN & BASU, 2014)OCKERMAN, H.W.; BASU, L. Carcass chilling and boning.In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences . 2ed. Oxford: Elsevier Ltd, 2014. p. 142-147..
There are no specific data on the sensory perception of lamb tenderness in Brazil, or on its influence on the consumer choice. Thus, this research investigated the consumer’s perception and its impacts on sensory evaluation in meats by induction of sarcomere shortening and aging, at different tenderness ranges.
MATERIAL AND METHODS
The project was approved by Ethics Research Committee of FZEA/USP (CAAE 44737515.6.0000.5422).
This study used 16 samples of the Longissimus dorsi muscle from half carcasses of eight lambs raised at sheep production sector at the Faculty of Animal Science and Food Engineering from the University of São Paulo (FZEA / USP). The lambs were from Santa Inês breed, not castrated and slaughtered at approximately 6 months old. They were raised in a semi-intensive management system in Coast-cross grass and supplemented with concentrate of 2% of live weight, offered once a day in a covered feeding trough. Water and mineral salts were offered ad libitum .
The 16 samples of LD were randomly distributed among four different types of postmortem processes; however, it was respected the same number of LD originated from right and left half carcass per treatment and ensuring that same animal would not have the same treatment assigned to both loins from its pair of half carcasses, to obtain different ranges of shear force (SF), as follow:
-
Toughened meat (TM): a procedure was conducted to ensure sarcomere shortening between 20 and 40% of resting sarcomere length to obtain higher shear force. For this reason, the muscles were excised immediately after slaughter, packed in plastic bags and then placed into a cool box with water and ice at 0ºC, where they were kept for 2 hours. The muscles were vacuum packaged and frozen until the analysis, according to Rees at al. (2002)REES, M.P.; TROUT, G.R.; WARNER, R.D. Tenderness of pork m. longissimus thoracis et lumborum after accelerated boning. Part I. Effect of temperature conditioning. Meat science , v.61, n.2, p.205-214, 2002..
-
Fresh meat (FM): the muscles were excised from the carcasses, that were kept in a cold chamber at 2-4ºC for 24 hours before deboning. The muscles were vacuum packaged and frozen until the analysis.
-
Aging meat for 3 days (A3): the LD was removed from the carcasses, that were kept in a cold chamber at 2-4ºC for 24 hours before deboning, and vacuum packaged, left to age at 1ºC for 3 days in a controlled temperature refrigerator, and frozen until the analysis.
-
Aging meat for 7 days (A7): the LD was removed from the carcasses, that were kept in a cold chamber at 2-4ºC for 24 hours before deboning, and vacuum packaged, left to age at 1ºC for 7 days in a controlled temperature refrigerator, and frozen until the analysis.
After completing the treatments, the following analyses were performed:
The pH and temperature. The pH was measured through a digital portable pH meter (model: DM-2, Digimed) and the temperature was measured with a digital spike thermometer (brand: Logen Scientific). Two measurements were made, one soon after slaughter and the other 24 hours post s laughter, except for the TM.
Thawing loss (TL). In this analysis, 3 steaks from LD with 2.5 cm of thickness were used. The samples were removed from the package, dried to remove exudate water, and weighed frozen. Afterward, they were frozen in a freezer with controlled temperature at 2°C overnight. On the next day, the samples were dried and weighed again. The TL was determined by the difference between weights before and after thawing (MISSIO et al., 2010MISSIO, R.L.; BRONDANI, I.L.; FILHO, D.C.A, RESTLE, J.; ARBOITTE, M.Z.; SEGABINAZZI, L.R. Características da carcaça e da carne de tourinhos terminados em confinamento, recebendo diferentes níveis de concentrado na dieta. Revista Brasileira de Zootecnia , v.39, n.7, p.1610-1617, 2010.).
Cooking loss (CL) . In this analysis, 3 steaks from LD of 2.5 cm thickness were used. The samples were weighed and cooked in a preheated electric oven. At 36ºC, the samples were turned over and kept in the oven until the internal temperature of 72ºC (temperature was controlled by a digital thermometer). Afterward, the steaks were left to cool at room temperature and were weighed again. The CL was determined by the difference between the weight after and before cooking (FELÍCIO, 1999FELÍCIO, P. Qualidade da carne bovina: características físicas e organolépticas. Reunião Anual da Sociedade Brasileira De Zootecnia , v.36, p.89-97, 1999.).
Shear force (SF) . The procedure was performed according to the recommendations of the American Meat Science Association - AMSA (2010) AMERICAN MEAT SCIENCE ASSOCIATION . Guidelines for uniform beef improvement programs . 9th ed. Chicago : National Livestock and Meat Board , 2010 . 185 p. Disponível em: < https://beefimprovement.org/library-2/bif-guidelines> . Acessed in: April 16, 2019 .
https://beefimprovement.org/library-2/bi...
. The same samples used to CL were used to analyze the shear force. Five to eight cylinders of 1.25cm of diameter, cut following the direction parallel to the muscle fibers, were removed from the steaks. The SF was measured through Warner-Bratzler texturometer (G-R Manufacturing Co., Manhattan, KS, USA). The results are expressed in kgf.
Myofibrillar fragmentation index (MFI) . The MFI was determined in accordance to procedures described by Culler et al. (1978) CULLER , R.D. ; PARRISH JR , F.C. ; SMITH , G.C. ; CROSS , H.R. Relationship of myofibril fragmentation index to certain chemical, physical and sensory characteristics of bovine Longissimus muscle . Journal of Food Science , v. 43 , n. 4 ,p. 1177 - 1180 , 1978 ., with the following adaptations: 1g of muscle sample was homogenized in 10 MFI buffer volume. The protein concentration was determined by the biuret method described by Gornall et al. (1949)GORNALL, A.G.; BARDAWILL, C.J.; DAVID, M.M. Determination of serum proteins by means of the biuret reaction. The Journal of Biological Chemistry ,v.177, n.2,p.751-766, 1949.. The protein concentration was adjusted to ensure the same protein concentration of 5 mg.ml -1 . The myofibrillar suspension was diluted and stirred, and absorbance was read immediately in the spectrophotometer (brand Unico, model 1205) at 540nm wavelength. The index was calculated according to Culler et al. (1978) CULLER , R.D. ; PARRISH JR , F.C. ; SMITH , G.C. ; CROSS , H.R. Relationship of myofibril fragmentation index to certain chemical, physical and sensory characteristics of bovine Longissimus muscle . Journal of Food Science , v. 43 , n. 4 ,p. 1177 - 1180 , 1978 ..
Sarcomere length (SL) . Five pieces (sub-samples) were cut transversely to the cross sectional area of LD from medial, dorsal-intermediary, intermediary, ventral-intermediary and lateral locations in the muscle surface. The fixation method for contrast microscope described by Cross et al. (1981) CROSS , H.R. ; WEST , R.L. ; DUTSON , T.R. Comparison of methods for measuring sarcomere length in beef semitendinosus muscle . Meat Science , v. 5 , n. 4 , p. 261 - 266 , 1981 . and Koolmees et al.(1986)KOOLMEES, P.A.; KORTEKNIE, F.; SMULDERS, F.J. Accuracy and utility of sarcomere length assessment by laser diffraction. Food Structure , v.5, n.1,71-76, 1986. was used in the analysis. Each sub-sample was place in a small bottle with 5% glutaraldehyde for 4 hours, and subsequently this solution was exchanged by a 0.2M sucrose solution and left over night. Both solutions have 0.1M phosphate buffer (pH=7.2) as basis. The samples can be kept in the sucrose solution up to 7 days. For slide preparation, each sub-sample was homogenized in Ultra-Turrax IKA (model T25 D), and a small part was placed on a slide and covered with a glass. In each slide, five different measurements were obtained and each measurement covered 10 to 20 sarcomeres of myofibrils linearly stretched. The Nikon Eclipse 80i contrast microscope was used with 100x magnifying lens. The Nikon Elements F program was used to measure the sarcomere in the photomicrographs.
Chemical composition . The samples were homogenized with a multiprocessor and chemical composition was determined in accordance to the ASSOCIATION OF OFFICIAL AGRICULTURAL CHEMISTS - AOAC (2005) AOAC . Official methods of analysis of the Association of Official Analytical Chemists International . 18 ed. Gaithersburg , Maryland , 2005 ., for the contents of moisture (method 950.46), ashes (method 920.153), lipids (method 991.36)and total protein for AOAC (1995) AOAC . Official methods of analysis of the Association of Official Analytical Chemists International . 16 ed. Gaithersburg , Maryland , 1995 . (method 981.10).
For sensorial analysis, the following preparations were made:
Samples preparation. After thawing in refrigerated environment (2ºC), the samples were immersed in 10 % sodium chloride solution and kept in the refrigerator for 30 minutes (SIQUEIRA et al., 2002SIQUEIRA, E.R.; ROÇA, R.D.O.; FERNANDES, S.; UEMI, A. Características sensoriais da carne de cordeiros das raças Hampshire Down, Santa Inês e Mestiços Bergamácia x Corriedale abatidos com quatro distintos pesos. RevistaBrasileira de Zootecnia , p.1269-1272, 2002.). Soon after, the samples were cut in steaks and cooked, as described in Cooking Loss. Immediately after cooking, the samples were chopped into cubes and kept in an oven at 50ºC for at most 15 minutes.
Sensory evaluation in individual booth . The evaluations were conducted in Laboratory of Sensory Analysis at FZEA/USP, with the participation of 50 untrained consumer panelists. These consumers were selected randomly within students of USP/Pirassununga between 18 and 25 years old and 57.7 % of the participants were women.
Free and Informed Consent Term was provided by the consumer panelists. Each consumer received a 2-cm3 meat sample from each treatment. Samples were presented in small and properly coded cups. The order of the treatments was randomized; therefore, consumers did not receive samples in the same sequence in consecutive panels. An acceptation test was conducted using the hedonic scale of nine points (1= Hated; 2= Very disliked; 3= Disliked moderately; 4= Slightly disliked; 5 = Not liked/not disliked; 6= Slightly liked; 7= Liked moderately; 8= Liked very much; 9= Loved), as described by Meilgaard et al. (1999)MEILGAARD, M.; CIVILLE, G.V.; CARR, B.T. Sensory evaluation techniques .New York:CRC Press, 1999. 281p.. The following characteristics were evaluated: tenderness, juiciness and overall quality.
The analysis for meat quality and percent composition used the analysis of variance (ANOVA) in the PROC MIXED, and means were tested by Tukey at 5% of significance. The sensory evaluation was processed using the non-parametric analysis, and the statistic difference was conducted using the Kruskal-Wallis test (PROC MIXED) at 1% of significance. Acceptance of meat sensory attributes was classified using the binomial test (PROC GLIMMIX) in which the grades were divided into two classes, agreed by the author as Satisfactory (from 6 to 9) and Unsatisfactory (from 1 to 5), and means were tested by Tukey at 1 % of significance. All data were analyzed using the statistical package SAS (SAS INSTITUTE INC., CARY, NC, USA).
RESULTS AND DISCUSSION
The percent composition of the loin samples from the four postmortem processes did not differ (p>0.05) ( Table 1 ), with average values of 75 %, 19 %, 4 % and 1 % for moisture, protein, lipid and ash, respectively. There was no impact of postmortem processing on the chemical composition, since the values corroborate with the literature (BONAGURIO et al., 2004 BONAGURIO , S. ; PÉREZ , J.R.O. ; FURUSHO-GARCIA , I.F. ; SANTOS , C.L.D. ; LIMA , A.L. Meat centesimal composition of purebred Santa Ines lambs and its crosses with Texel, slaughtered at different weights . Revista Brasileira de Zootecnia , v. 33 , n. 6 ,p. 2387 - 2393 , 2004 .; ZAPATA et al., 2011ZAPATA, J.F.F.; NOGUEIRA C.M.; SEABRA, L.M.J.; BARROS, N.N.; BORGES, A.S. Composições centesimal e lipídica da carne de ovinos do Nordeste brasileiro. Ciência Rural , Santa Maria, v. 31, n. 4, p. 691-695, 2001.).
There was no significant difference between the pH values at 0h00 and average value of 6.73 ± 0.15 was within expectation, near neutral values. The pH measured at 24h00 had no significant differences between processes and were within the normal range for lamb meat, which for post rigor meat, are between 5.4 and 5.8. The average values were 5.63 ± 0.04 ( Table 2 ). The pH 24h00 for TM was not measured.
Considering the conditions of pH and temperature, the TM samples had all the conditions to characterize sarcomere shortening, due to muscle cooling in water at 0°C and initial pH around 6.72 – conditions that favor high shear force values. These conditions are predisposing factors for cold shortening, which occurs in muscles when pH is greater than 6 and temperature is below 10°C (LOCKER & HAGYARD, 1963LOCKER, R.H.; HAGYARD, C.J.A cold shortening effect in beef muscles. Journal of the Science of Food and Agriculture ,v.14, n.11, 787-793, 1963.).
For TM, the sarcomere length was 1.44 µm ( Table 2 ), showing a shortening of 35 % when compared to the resting sarcomere length of 2.2 µm obtained for lambs (WHEELER & KOOHMARIE, 1999WHEELER, T.L.; KOOHMARAIE, M. The extent of proteolysis is independent of sarcomere length in lamb longissimus and psoas major. Journalof Animal Science , v.77, n.9, p.2444-2451, 1999.). This shortening level allowed lower meat tenderness, when comparing meat that remained on carcass for 24 h ( post rigor ) or aged meat (M3 and M7); however, samples that did not undergo shortening differ from each other ( Table 2 ). The shortening between 20 and 40 % was responsible for meat tightening (MARSH & LEET, 1966)MARSH, B.T.; LEET, N.G. Studies in meat tenderness. III. The effects of cold shortening on tenderness. Journal of Food Science ,v.31, n.3, p. 450-459, 1966.. High shear force values were also obtained at 24h postmortem in lamb meat with an average sarcomere length of 1.69 µm (WHEELER & KOOHMARAIE, 1994)WHEELER, T.L.; KOOHMARAIE, M.Prerigor and postrigor changes in tenderness of ovine longissimus muscle. Journal of Animal Science ,v.72, n.5,p.1232-1238, 1994. The sarcomere shortening, which occurs during the rigor mortis, is responsible for tightening the muscles, causing the toughening of Longis simus muscle in lambs (KOOHMARAIE et al., 2002)KOOHMARAIE, M. KENT, M.P.; SHACKELFORD, S.D.; VEISETH, E.; WHEELER, T.L. Meat tenderness and muscle growth: is there any relationship? Meat Science ,v.62, n.3,p.345-352, 2002. After rigor, the sarcomere length did not change significantly in samples processed after 24h postmortem ( Table 2 ).
The change in the shear force resulting from aging was not observed and the only difference verified in tenderness was related to the induction of cold shortening for TM ( Table 2 ). The lack of differences between aged meats was not expected, since the objective of this work was to create tenderness ranges by exposing samples to cold shortening or aging, once larger changes in shear forces occur between the 1 st and 7 th day of the aging process (KOOHMARAIE et al., 1991KOOHMARAIE, M.; WHIPPLE, G.; KRETCHMAR, D.H.; CROUSE, J.D.; MERSMANN, H.J. Postmortem proteolysis in longissimus muscle from beef, lamb and pork carcasses. Journal of Animal Science ,v.69, n.2, p. 617-624, 1991., 1995KOOHMARAIE, M.; SHACKELFORD, S.D.; WHEELER, T.L.; LONERGAN, S.M.; DOUMIT, M.E.A muscle hypertrophy condition in lamb (callipyge): characterization of effects on muscle growth and meat quality traits. Journal of Animal Science , v.73, n.12, p.3596-3607, 1995., STARKEY et al., 2015STARKEY, C.P.; GEESINK, G.H.; ODDY, V.H.; HOPKINS, D.L.Explaining the variation in lamb longissimus shear force across and within ageing periods using protein degradation, sarcomere length and collagen characteristics. Meat Science ,v.105, p.32-37, 2015.).However, the temperature of the carcasses after slaughter did not have an expected cooling rate, reaching 12 to 15°C at 24 hours post mortem , which probably allowed rapid tenderization of FM and the aged samples. Incubation temperatures of the muscle Longissimus between 15ºC to 20ºC during rigor onset (first 16 hours post mortem ) minimized the toughening effects of the muscle and accelerated the postmortem glycolysis process, with increased Desmin, Titin and Troponin-T degradation and m-calpain autolysis, resulting in lower shear force at 1day postmortem compared to very low (5ºC) or very high (> 30ºC) temperatures (GEESINK et al., 2000GEESINK, G.H.; BEKHIT, A.D.; BICKERSTAFFE, R.Rigor temperature and meat quality characteristics of lamb longissimus muscle. Journal of animal science, v.78, n.1,p.2842-2848, 2000.). These protein degradation patterns are all indicators of enhanced proteolysis and positively related to tenderization rate (DELGADO et al., 2001)DELGADO, E.F.; GEESINK, G.H.;MARCHELLO, J.A.; GOLL, D.E.; KOOHMARAIE, M.The calpain system in three muscles of normal andcallipyge sheep. Journal of Animal Science , v.79, n.2, p.398-412, 2001..
In lambs, the lack of differences between A3 and A7 were observed before, due to the faster tenderization process (GEESINK et al., 2000GEESINK, G.H.; BEKHIT, A.D.; BICKERSTAFFE, R.Rigor temperature and meat quality characteristics of lamb longissimus muscle. Journal of animal science, v.78, n.1,p.2842-2848, 2000.). This system also confirms that tender meats right after rigor tend not to have tenderizing effects due to the aging time. Although, differences could exist because of the fragility of myofibrillar structure caused by the postmortem proteolysis (MILLER, 2014MILLER, R.K.Chemical and physical characteristics of meat: palatability. In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences .2ed. Oxford: ElsevierLtd, 2014. p. 252-261.). Although there were no differences in shear force, the MFI seems to show a gradual increase of myofibrils fragmentation within the aging process. This study showed an increase in MFI, with significant difference observed between TM and A7, while FM and A3 did not differ between the PS ( Table 2 ). The results were similar to those observed for older crossbred lambs, except for the major changes reported in MFI between the 3 rd and 7 th day of aging (GONÇALVES, et al. 2004). On the other hand, the lack of changes in shear force even with a steady increase in MFI were observed in callipygian lambs (KOOHMARAIE et al., 1995KOOHMARAIE, M.; SHACKELFORD, S.D.; WHEELER, T.L.; LONERGAN, S.M.; DOUMIT, M.E.A muscle hypertrophy condition in lamb (callipyge): characterization of effects on muscle growth and meat quality traits. Journal of Animal Science , v.73, n.12, p.3596-3607, 1995.).
The postmortem process resulted in greater thawing loss for TM and FM, compared to A3 and A7 ( Table 2 ). The CL did not show differences, probably due to excessive thawing losses in MT and FM. The greater loss observed is linked to the storage of these muscles. Both processes underwent sarcomere shortening during the rigor mortis , and consequently the intramyofibrilar water spilled to the extramyofibrilar and extracellular spaces. However, this water is eventually retained in the meat, without the possibility of exudation because of sample freezing. On the other hand, muscles that undergo a longer aging time (3 and 7 days after slaughter), due to water channels formed in the extracellular space during aging, have drip losses with less free water retained in the extracellular spaces (DEVINE et al., 2014DEVINE, C.E.; WELLS, R.W.; LOWE, T.; WALLER, J. Pre-rigor temperature and the relationship between lamb tenderisation, free water production, bound water and dry matter. Meat Science , v.96, n.1, p.321-326, 2014.).
Postmortem processing | ||||||
---|---|---|---|---|---|---|
Variables | N | TM | FM | A3 | A7 | P Value |
Texture | 50 | 5.47 b | 7.43 a | 7.58 a | 7.66 a | <0.01 |
Juiciness | 50 | 6.45 b | 7.75 a | 7.57 a | 7.57 a | <0.01 |
Overall Quality | 50 | 5.92 b | 7.37 a | 7.53 a | 7.54 a | <0.01 |
The scores attributed to TM, which had SF of 7.2 kgf, were low compared to other processes, showing that SF has great impact on the sensory evaluation of consumers.
Samples classified as tenderer (SF below 3.40 kgf) received high scores in the sensory evaluation, except for TM. Meat of crossbred lamb (female and castrated) was qualified by consumers as tenderer, with values between 3.2 and 3.5 kgf, when compared to uncastrated lambs, which had SF of 4.1 kgf (GONÇALVES et al., 2004GONÇALVES, L.A.; ZAPATA, J.F.; RODRIGUES, M.C.P.; BORGES, A.S.The effects of sex and aging on lamb meat quality. Ciência e Tecnologia de Alimentos ,v.24, n.3, p.459-467, 2004.), close to the threshold value of tender meat for consumers (<4.1 kgf) (MILLER et al., 2001MILLER, M.F. CARR, M.A.; RAMSEY, C.B.; CROCKETT, K.L.; HOOVER, L.C. Consumer thresholds for establishing the value of beef tenderness. Journal of Animal Science ,v.79, n.12, p.3062-3068, 2001.; DELGADO et al., 2006)DELGADO, E.F.; AGUIAR, A.P.; ORTEGA, E.M.M.; SPOTO, M.H.F.; CASTILLO, C.J.C. Brazilian consumers' perception of tenderness of beef steaks classified by shear force and taste. Scientia Agricola ,v.63, n.3, p.232-239, 2006.. Gonçalves et al. (2004)GONÇALVES, L.A.; ZAPATA, J.F.; RODRIGUES, M.C.P.; BORGES, A.S.The effects of sex and aging on lamb meat quality. Ciência e Tecnologia de Alimentos ,v.24, n.3, p.459-467, 2004. used older lambs (15 months old with two permanent teeth) and, for this reason, other attributes, such as flavor and odor, probably influenced the low acceptance of uncastrated males. Different from the results of this research, which used young uncastrated lambs (6 months old).
In the acceptance analysis, TM obtained the lowest rates, resulting in a uniform distribution of scores in the lower range. The lowest preference for TM could be related to increase in shear force. Texture perception is highly affected by shear force for consumers of lamb meat. Samples with SF values lower than 2.7 kg were rated as high quality for most Australian consumers, while changing this threshold of SF to values lower than 4.9 kg, consumer acceptance decreased (HOPKINS et al., 2006HOPKINS, D.L.; HEGARTY, R.S.; WALKER, P.J; PETHICK, D.W. Relationship between animal age, intramuscular fat, cooking loss, pH, shear force and eating quality of aged meat from sheep. Australian Journal of Experimental Agriculture ,v.46, n.7,p.879-884, 2006.).
Although FM and A3 had no differences when compared to A7, some comments were made in the evaluation for A7 samples, such as “the score was not higher, because this meat was too tender”, “this meat was too viscous”, or “it disintegrated too easy in the mouth”. These samples presented greater MFI ( Table 2 ). These observations may indicate that exaggerated fragmentation of the myofibrillar structure in lamb meat may have detrimental influence on texture perception of some consumers. This may be explained by the high correlation (r=0.75) between MFI and the texture (CULLER et al., 1978 CULLER , R.D. ; PARRISH JR , F.C. ; SMITH , G.C. ; CROSS , H.R. Relationship of myofibril fragmentation index to certain chemical, physical and sensory characteristics of bovine Longissimus muscle . Journal of Food Science , v. 43 , n. 4 ,p. 1177 - 1180 , 1978 .).
Evaluating juiciness shows that TM is still the less accepted meat, even with better scores than for texture. Although there were no changes in moisture between the processes ( Table 1 ), TM received comments as “this meat is too dry”, which could probably happen since consumers tend to confuse juiciness with texture, associating tough meat to dry meat (MILLER, 2014MILLER, R.K.Chemical and physical characteristics of meat: palatability. In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences .2ed. Oxford: ElsevierLtd, 2014. p. 252-261.).
In addition, A7 was more penalized regarding juiciness and were not different from TM. This reinforces the fact that MFI could influence acceptance, once juiciness is the moisture sensation in the first chewing, and it would not be clearly evaluated if the meat ‘disintegrates’ easily in the mouth.
The analysis of Overall Quality ( Table 4 ) allows identifying the influence of juiciness and texture and the effects of other attributes not covered in this research, such as flavor, which also influence customers’ preference. This observation based on comments related to odor and taste that were not part of the attributes evaluated.
In the overall quality assessment, TM also received the lowest score, reflecting the results of texture and juiciness. Another element that may contribute to lower evaluations in the Overall Quality is odor, which presented comments as “strong odor” and “unpleasant odor”. On the other hand, A7 was not penalized in the overall quality assessment when compared with either FM or A3, even though it had an unsatisfactory evaluation for juiciness, considering the distribution of scores. Therefore, even though lamb meat with very high MFI and low SF may be penalized, this was not enough to result in lower perception of overall quality. However, meat with low MFI and a high SF was consistently penalized and had a large number of unsatisfactory scores. The data suggests that texture plays a major role in the evaluation of the untrained consumers. Furthermore, since FM and A3 received the best scores in all attributes evaluated, those samples may be considered as standards for lamb meat quality.
CONCLUSION
Meat toughness caused by cold shortening has a negative impact on not only meat texture, but also on juiciness and overall quality evaluation by consumers.
The prolonged period of aging and greater myofibrillar fragmentation associated with it compromise evaluation of juiciness.
ACKNOWLEDGEMENTS
We will would like acknowledge USP-Pirassununga Main Office for the donation of meat samples, CAPES for scholarship to the first author and Priscila A. Trevisoli for helping in the paper translation.
REFERENCES
- AMERICAN MEAT SCIENCE ASSOCIATION . Guidelines for uniform beef improvement programs . 9th ed. Chicago : National Livestock and Meat Board , 2010 . 185 p. Disponível em: < https://beefimprovement.org/library-2/bif-guidelines> . Acessed in: April 16, 2019 .
» https://beefimprovement.org/library-2/bif-guidelines> - ANDRADE , J.C. SOBRAL , L.A. ; ARES , G. ; DELIZA , R. Understanding consumers' perception of lamb meat using free word association . Meat Science , v. 117 , p. 68 - 74 , 2016
- AOAC . Official methods of analysis of the Association of Official Analytical Chemists International . 16 ed. Gaithersburg , Maryland , 1995 .
- AOAC . Official methods of analysis of the Association of Official Analytical Chemists International . 18 ed. Gaithersburg , Maryland , 2005 .
- BONAGURIO , S. ; PÉREZ , J.R.O. ; FURUSHO-GARCIA , I.F. ; SANTOS , C.L.D. ; LIMA , A.L. Meat centesimal composition of purebred Santa Ines lambs and its crosses with Texel, slaughtered at different weights . Revista Brasileira de Zootecnia , v. 33 , n. 6 ,p. 2387 - 2393 , 2004 .
- BRASIL . Ministério da Agricultura Pecuária e Abastecimento . Available in: < http://www.agricultura.gov.br> . Acessed in: June 10, 2016 .
» http://www.agricultura.gov.br> - CROSS , H.R. ; WEST , R.L. ; DUTSON , T.R. Comparison of methods for measuring sarcomere length in beef semitendinosus muscle . Meat Science , v. 5 , n. 4 , p. 261 - 266 , 1981 .
- CULLER , R.D. ; PARRISH JR , F.C. ; SMITH , G.C. ; CROSS , H.R. Relationship of myofibril fragmentation index to certain chemical, physical and sensory characteristics of bovine Longissimus muscle . Journal of Food Science , v. 43 , n. 4 ,p. 1177 - 1180 , 1978 .
- DELGADO, E.F.; GEESINK, G.H.;MARCHELLO, J.A.; GOLL, D.E.; KOOHMARAIE, M.The calpain system in three muscles of normal andcallipyge sheep. Journal of Animal Science , v.79, n.2, p.398-412, 2001.
- DELGADO, E.F.; AGUIAR, A.P.; ORTEGA, E.M.M.; SPOTO, M.H.F.; CASTILLO, C.J.C. Brazilian consumers' perception of tenderness of beef steaks classified by shear force and taste. Scientia Agricola ,v.63, n.3, p.232-239, 2006.
- DEVINE, C.E.; WELLS, R.W.; LOWE, T.; WALLER, J. Pre-rigor temperature and the relationship between lamb tenderisation, free water production, bound water and dry matter. Meat Science , v.96, n.1, p.321-326, 2014.
- FELÍCIO, P. Qualidade da carne bovina: características físicas e organolépticas. Reunião Anual da Sociedade Brasileira De Zootecnia , v.36, p.89-97, 1999.
- FIRETTI, R.; CARRER, C.D.C.; SILVA, V.L.; TRINDADE, M.A.; SOUZA, S.C.D.; SAVASTANO JR, H.; RIBEIRO, M.M.L.O.The perception of Sao Paulo state consumers in relation to ship meat: analysis by principal components. Revista Brasileira de Saúde e Produção Animal ,v.11, n.1,p.1-13, 2010.
- FREIRE, M.T.A.; NAKAO, M.Y.; GUERRA, C.C.; CARRER, C.C.; SOUZA, S.C.; TRINDADE, M.A. Determinação de parâmetros físico-químicos e de aceitação sensorial da carne de cordeiros proveniente de diferentes tipos raciais. Alimentos e Nutrição Araraquara , v. 21, n. 3, p. 481-486, 2010.
- GEESINK, G.H.; BEKHIT, A.D.; BICKERSTAFFE, R.Rigor temperature and meat quality characteristics of lamb longissimus muscle. Journal of animal science, v.78, n.1,p.2842-2848, 2000.
- GONÇALVES, L.A.; ZAPATA, J.F.; RODRIGUES, M.C.P.; BORGES, A.S.The effects of sex and aging on lamb meat quality. Ciência e Tecnologia de Alimentos ,v.24, n.3, p.459-467, 2004.
- GORNALL, A.G.; BARDAWILL, C.J.; DAVID, M.M. Determination of serum proteins by means of the biuret reaction. The Journal of Biological Chemistry ,v.177, n.2,p.751-766, 1949.
- HOPKINS, D.L.; HEGARTY, R.S.; WALKER, P.J; PETHICK, D.W. Relationship between animal age, intramuscular fat, cooking loss, pH, shear force and eating quality of aged meat from sheep. Australian Journal of Experimental Agriculture ,v.46, n.7,p.879-884, 2006.
- INSTITUTO FNP. ANUALPEC 2014:anuário da pecuária brasileira. 20. ed. São Paulo, 2014. 213p.
- KOOHMARAIE, M.; WHIPPLE, G.; KRETCHMAR, D.H.; CROUSE, J.D.; MERSMANN, H.J. Postmortem proteolysis in longissimus muscle from beef, lamb and pork carcasses. Journal of Animal Science ,v.69, n.2, p. 617-624, 1991.
- KOOHMARAIE, M.Muscle proteinases and meat aging. Meat Science ,v.36, n.1-2, p.93-104, 1994.
- KOOHMARAIE, M.; SHACKELFORD, S.D.; WHEELER, T.L.; LONERGAN, S.M.; DOUMIT, M.E.A muscle hypertrophy condition in lamb (callipyge): characterization of effects on muscle growth and meat quality traits. Journal of Animal Science , v.73, n.12, p.3596-3607, 1995.
- KOOHMARAIE, M., SHACKELFORD, S. D. WHEELER, T.L. Effect or prerigor freezing and postrigor calcium chloride injection on the tenderness of callipygelongissimus. Journal of Animal Science, v.76, n.5, p. 1427-1432, 1998.
- KOOHMARAIE, M. KENT, M.P.; SHACKELFORD, S.D.; VEISETH, E.; WHEELER, T.L. Meat tenderness and muscle growth: is there any relationship? Meat Science ,v.62, n.3,p.345-352, 2002
- KOOLMEES, P.A.; KORTEKNIE, F.; SMULDERS, F.J. Accuracy and utility of sarcomere length assessment by laser diffraction. Food Structure , v.5, n.1,71-76, 1986.
- LOCKER, R.H.; HAGYARD, C.J.A cold shortening effect in beef muscles. Journal of the Science of Food and Agriculture ,v.14, n.11, 787-793, 1963.
- MARSH, B.T.; LEET, N.G. Studies in meat tenderness. III. The effects of cold shortening on tenderness. Journal of Food Science ,v.31, n.3, p. 450-459, 1966.
- MEILGAARD, M.; CIVILLE, G.V.; CARR, B.T. Sensory evaluation techniques .New York:CRC Press, 1999. 281p.
- MILLER, M.F. CARR, M.A.; RAMSEY, C.B.; CROCKETT, K.L.; HOOVER, L.C. Consumer thresholds for establishing the value of beef tenderness. Journal of Animal Science ,v.79, n.12, p.3062-3068, 2001.
- MILLER, R.K.Chemical and physical characteristics of meat: palatability. In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences .2ed. Oxford: ElsevierLtd, 2014. p. 252-261.
- MISSIO, R.L.; BRONDANI, I.L.; FILHO, D.C.A, RESTLE, J.; ARBOITTE, M.Z.; SEGABINAZZI, L.R. Características da carcaça e da carne de tourinhos terminados em confinamento, recebendo diferentes níveis de concentrado na dieta. Revista Brasileira de Zootecnia , v.39, n.7, p.1610-1617, 2010.
- MONIN, G.; SANTÉ-LHOUTELLIER, V. Conversion of muscle to meat: color and texture deviations. In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences .2ed. Oxford: Elsevier Ltd, 2014. p. 339-345.
- OCKERMAN, H.W.; BASU, L. Carcass chilling and boning.In: DIKEMAN, M.; DEVINE, C. (Ed). Encyclopedia of Meat Sciences . 2ed. Oxford: Elsevier Ltd, 2014. p. 142-147.
- REES, M.P.; TROUT, G.R.; WARNER, R.D. Tenderness of pork m. longissimus thoracis et lumborum after accelerated boning. Part I. Effect of temperature conditioning. Meat science , v.61, n.2, p.205-214, 2002.
- SIQUEIRA, E.R.; ROÇA, R.D.O.; FERNANDES, S.; UEMI, A. Características sensoriais da carne de cordeiros das raças Hampshire Down, Santa Inês e Mestiços Bergamácia x Corriedale abatidos com quatro distintos pesos. RevistaBrasileira de Zootecnia , p.1269-1272, 2002.
- STARKEY, C.P.; GEESINK, G.H.; ODDY, V.H.; HOPKINS, D.L.Explaining the variation in lamb longissimus shear force across and within ageing periods using protein degradation, sarcomere length and collagen characteristics. Meat Science ,v.105, p.32-37, 2015.
- WHEELER, T.L.; KOOHMARAIE, M.Prerigor and postrigor changes in tenderness of ovine longissimus muscle. Journal of Animal Science ,v.72, n.5,p.1232-1238, 1994
- WHEELER, T.L.; KOOHMARAIE, M. The extent of proteolysis is independent of sarcomere length in lamb longissimus and psoas major. Journalof Animal Science , v.77, n.9, p.2444-2451, 1999.
- ZAPATA, J.F.F.; NOGUEIRA C.M.; SEABRA, L.M.J.; BARROS, N.N.; BORGES, A.S. Composições centesimal e lipídica da carne de ovinos do Nordeste brasileiro. Ciência Rural , Santa Maria, v. 31, n. 4, p. 691-695, 2001.
Publication Dates
-
Publication in this collection
29 July 2019 -
Date of issue
2019
History
-
Received
07 Feb 2019 -
Accepted
26 June 2019