HAM QUALITY AND ITS RELATIONSHIPS TO CARCASS QUALITY 11. Spesifit weight and dissection analysis of the ham Unto Uusisalmi Department ofAnimal Breeding, University ofHelsinki Received January 28, 1971 Abstract. Ham quality and its relationship to carcass quality were investigated in Landrace and Yorkshire pigs at the Puistola (n = 97) and Pohjanmaa (n = 103) litter testing stations by means of specific weight of the ham and dissection analysis of the ham and the most valuable part of the carcass. The material was processed by means of factor analysis. The greatest loading in the first factor was acquired by the fat-% of the ham (0.93), the second greatest by the meat-% of the ham (—0.90), the third greatest by the skin -(- fat part of the ham (0.89), and the fourth by the percentage of the skin + fat component of the most valuable part of the carcass (0.82). The skin + fat part of the ham correlated very significantly with the skin + fat component of the most valuable part of the carcass (Puistola r = 0.76, Pohjanmaa r = 0.74), and meat + bone part of the ham with the meat + bone component of the most valuable part of the carcass (Puistola r = 0.83, Pohjanmaa r = 0.81). In the Pohjanmaa material (n = 99) the phenotypical and genotypical correlations of the ham, back and their components with the carcass and its equivalent components were found to be relatively uniform. The only exception was the correlation of the meat -f- bone of the ham with the meat + bone of the most valuable part of the carcass (rphen. = 0.83, rgCn. = 0.48). No significant phenotypical or genotypical correlation was found between the skin + fat of the ham and meat + bone of the ham. The object of the present study is (1) to analyse the slaughter quality of the ham by means of specific weight and dissection analysis, and (2) to compare the dissection results of the ham and of the most valuable part of the carcass. Material and statistical method Data were collected on 200 carcasses of Landrace and Yorkshire pigs reared to 90 kg live weight at the Puistola (n = 97) and Pohjanmaa (n = 103) litter testing stations. Conventional carcass evaluation was made on day after slaughter. The left half of the carcass was cut and dissected in the manner presented by Uusisalmi (1969 a). The https://www.c-info.fi/en/info/?token=LZyXmkaOzkuFMSRf.UXL8FuFYf__KML64t5th6w.t1_xk1gXT5X8qXrPybiVRvZQLUhfPoYLandekUuTR2QPEyl1fqb-3X8CIGAkuEKMBfw4eOlHiWIL0o0ZM1IpRRBR08j3tczSPpok4DD1ILvf3B-L8SzvvIeMO5QIymU6Ccqjn3TmeioC64v3m3Lipl0HUojES6N_m8jWKQ 141 specific weights of the ham and the shoulder were determined, these were then dissected to separate the various tissues: skin, fat, meat and bones. During the measurements carried out at the Pohjanmaa testing station, the feed was changed from barley, maize and skim milk to standard mixture. Factor analysis was used to clarify the relationships between the dissection results on the ham and the most valuable part of the carcass and its skin + fat component and meat -f- bone component (n = 200). Factorisation was done from the correlation matrix (Vahervuo & Ahmavaara 1958 and Harman 1960) of the phenotype, and the rotation by the Varimax method (Harman 1960). In Finland factor analysis in the formation of groups of characteristics has been used by Varo on horses (1962 and 1966), pigs (1965) and sheep (1968) and by Maijala (1966) on poultry. The phenotypical and genotypical correlationof the skin + fat component and meat -f- -bone part of the ham and the back to the respective components obtained from the dis- section results of the most valuable part of the carcass were determined (Pohjanmaa, n = 99); results obtained included rphen . = the phenotypical correlation coefficient calculated from the total variation, rgen . = the genotypical correlation coefficient calcu- lated from the genetic variation, and rres . = the pheotypical correlation coefficient calculated from the error variation. Results Factor analysis (Puistola and Pohjanmaa, n = 200). The means, standard deviations and variation coefficients of certain dissection results on the ham and the most valuable part of the carcass, and of the specific weight of the ham that were included in the factor analysis, are shown in Table 1. The phenotypical correlations of the same characteristics are shown in Table 2. Of the 30 characteristics included, 2 characteristics had to be eliminated on account of a systematic error in the cards. The »error factor», a seventh factor formed on account of an error, was likewise omitted from the results of the factor analysis. Both eliminated characteristics acquired the greatest loadings in the eliminated factor. The other six factors formed after rotation, and their loadings, can be seen in Table 3 and Fig. 1. The first factor (Fig. 1) shows that it generally measures the fattiness and meatiness of the ham and the most valuable part of the carcass. The greatest loading in this factor was acquired by the fat-% of the ham (0.93), and the second greatest by the meat-% of the ham. The factor measures third best the skin + fat component of the ham, and fourth best the percentage of the skin -)- fat component of the most valuable part of the carcass. It may also be mentioned that the specific weight ranhed as low as eighth with the loading —0.62. The second factor measures the quantity and percentage of bone of the ham and the shank. The hind shank, with its second biggest loading (0.99), proves a good indicator of the amount of bone in the ham + shank. The weight of the ham + shank and its meat -(- bone part acquire the greatest load- ing in the third factor. The fourth greatest loadings are acquired by the meat bone of the most valuable part of the carcass and the most valuable part of the carcass (0.69). The fourth factor is measuring the quantity of skin of the ham and the shank. 142 Table 1. Averages, standard deviations and varition coefficients of dissection results at the litter testing stations of Puistola and Pohjanmaa, n = 200 Characteristics Puistola station Pohjanmaa station Total material x 8 variat.% x 8 variat.% x 8 variat. % 1 Live weight 90.41 1.88 2.07 89.32 2.55 2.85 89.85 2.31 2.57 2 Age days 167.20 8.49 5.07 178.99 12.84 7.17 173.27 12.42 7.16 3 Skin % of ham 3.86 0.55 14.24 4.25 0.63 14.82 4.06 0.62 15.27 4 Fat % of ham 16.56 2.60 15.70 17.25 2.45 14.20 16.92 2.54 15.01 5 Skin of ham + shank, g 323 44 13.62 349 52 14.90 336 50 14.88 6 Fat of ham + shank, g 1169 187 16.00 1231 342 27.78 1201 279 23.23 7 Fat %of ham + shank 16.17 2.47 15.27 17.57 6.92 39.38 16.89 5.29 31.32 8 Skin + fat of shoulder, g 883 140 15.86 935 189 20.21 910 176 19.34 9 Skin + fat of ham, g 1295 177 13.67 1346 179 13.30 1322 183 13.84 10 Skin + fat of the most valuable part, g 5668 696 12.28 5638 654 11.60 5652 673 11.91 11 Skin + fat component, % of carcass 16.75 1.98 11.82 17.11 1.74 10.16 16.94 1.86 10.97 12 Meat %of ham 72.39 2.60 3.59 71.49 2.43 3.39 71.93 2.55 3.54 13 Specific weight of ham 1.059 0.004 1.054 0.005 1.056 0.005 14 Meat of hind shank, g 314 30 9.55 299 35 11.71 306 34 11.11 15 Meat of ham + shank, g 4958 347 7.00 4776 383 8.01 4864 366 7.53 16 Meat %of ham + shank 68.51 2.47 3.60 67.59 2.74 4.05 68.04 2.64 3.88 17 Meat + bone of shoulder, g 2943 230 7.82 3185 266 8.35 3068 279 9.09 18 Meat + bone of ham, g 5115 352 6.88 4942 341 6.90 5206 355 6.82 19 Meat + bone of the most valuable part, g 15210 874 5.75 15545 964 6.20 15383 934 6.07 20 Meat + bone component, %of carcass 44.98 2.08 4.62 47.19 1.89 4.00 46.12 2.27 4.92 21 Bone %of ham 7.53 0.58 7.70 7.14 0.66 9.24 7.33 0.65 8.86 22 Bone of hind shank, g 325 27 8.31 322 28 8.70 323 28 8.67 23 Bone of ham + shank, g 808 61 7.55 696 76 10.92 750 55 7.33 24 Bone %ofham + shank 11.18 0.84 7.51 11.62 0.77 6.62 11.41 0.79 6.92 25 Hind shank, g 821 63 7.67 892 75 8.41 858 52 6.18 26 Ham + shank, g 7233 387 5.35 7109 400 5.63 7169 398 5.55 27 The most valuable part, g 20878 853 4.09 21182 1126 5.23 21035 1012 4.81 28 The most valuable part, %of carcass 61.73 1.34 2.17 64.30 1.32 2.05 63.06 1.85 2.93 The fifth factor is a factor measuring the skin + fat part and meat + bone part of the shoulder (shoulder factor). However, this factor also reveals the significance ofshoulder as addition to the most valuable part of the carcass. Phenotypical and genotypical correlations (Pohjanmaa, n = 99). Table 4 shows the phenotypical and genotypical correlations of ham and back and their skin -f- fat and meat + bone parts with the most valuable part of the carcass and its skin + fat and meat + bone components. The correlation coefficients calculated from the total variation varied from 0.66 to 0.83, and the genetic correlation coefficients calcul- ated from the variation between sires from 0.48 to 0.89. It may be pointed out that the Table 2. The correlation coefficients of the dissection data (n = 200) (—0.09 = 09; 0.49 = 49). Cf. the factor analysis. 2 34 56 7 89 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | ~T 09 —O6 08 05 07 — O4 16 21 37 14 08 14 20 30 —O6 14 28 26—27 02 20 10 — O7 — O5 39 49 — 2O 1 2 —O4 01 — O6 01 01 14 00—O3 —Ol 01—33—ll—O4—O3 37 —O6 14 23—l9— O5 — Ol —O4 —Ol —O5 10 27 2 3 13 86 02 04 06 23 15 24 —39 —O6 —OB —32 —39 —O3 —35 —l4 —O2 10 08 02 00 —Ol —lB —O3 22 3 4 11 62 48 38 90 74 80 —93 —59 —24 —44 —7B —34—47 —49 —59—4O — 4O —OB —O3 01 —O4 04 08 4 5 28 25 —O2 35 18 18 —29 —O4 17 —lO —l9 —O2 —O2 05 04 —O5 14 —22 23 28 19 05 23 5 6 95 20 68 46 45 —5l —42 —O6 —34 —ll —l9 —O3 —l3 —26 —45 —27 —7B 70 76 25 18 13 6 7 15 47 31 34 —4l —36 —l2 —5l 02 —lB —l5 —l9 —2O —34 —27 —9l 85 88 03 03 10 7 8 31 60 59 —39 —46 —l3 —23 —3B 31 —26 —lB —36 —lO —2O 02 —O7 —O4 —lO 24 15 8 9 74 71 —B2 —5O —OB —l3 —65 —23 —l2 —2l —44 —5O —26 —ll —OO 07 34 30 18 9 10 94 —6B —46 —lO —lB —5B —l4 —23 —23 —62 —34 —2B —OO —lO —O4 13 44 19 10 H —77 —55—2l—4l —67—23 —47 —4B —62 —4O — 42 — O3 —OB —O4 — l2 18 25 11 12 52 25 57 89 31 61 54 59 14 24 02 03 02 18 05 —O5 12 13 19 35 44 —O3 37 30 23 45 39 15 —O2 —O9 11 —O3 —29 13 14 45 23 01 41 23 05 10 26 05 —Ol 08 45 15 —l5 14 15 42 26 90 66 34 —ll 29 39 —3B —3l 80 49 01 15 16 22 63 51 54 —O2 11 -40 43 42 24 09 —Ol 16 17 28 59 54 06 24 07 —O3 —O3 17 45 43 17 18 74 41 —l2 34 —O2 05 11 88 53 03 18 19 72 —O5 43 01 04 07 60 76 40 19 20 —O4 27 —O6 09 08 17 25 61 20 21 57 25 —O2 —l4 —29 —2B —4O 21 22 19 02 —O2 26 21 —O9 22 22 r > 0.14 signif. at 5 % level — 97 —9B 02 00 10 23 23 r > 0.19 signif. at 1 % level 98 01 02 02 24 24 r > 0.24 signif. at 0.1 % level H 94 06 25 o = 64 09 26 26 49 27 27 143 1 Live weight 2 Live weight 3 Skin % of ham 4 Fat % of ham 5 Skin ofham+shank, g 6 Fat of ham+shank, g 7 Fat % of ham+shank 8 Skin + fat of shoulder, g 9 Skin + fat of ham, g 10 Skin+ fat of most valuable part, g 11 Skin + fat component, 20 Meat +bone component, % of carcass % ofcarcass 12 Meat % of ham 21 Bone % ofham 13 Specific weight ofham 22 Bone of hind shank, g 14 Meat of hind shank, g 23 Bone of ham+shank, g 15 Meat of ham+ shank, g 24 Bone % of ham +shank 16 Meat % of ham+shank 25 Hind shank, g 17 Meat +bone of shoulder, g 26 Ham+ shank, g 18 Meat + bone of ham, g 27 Most valuable p27 Most valuable part of 19 Meat + bone of most carcass, g valuable part, g 28 Most valuable part, % of carcass genotypical correlation coefficients between the dissection results on the back and the most valuable part of the carcass were slightly greater than the genotypical correlation coefficients between the dissection results on the ham and the most valuable part of the carcass. Discussion In the factor analysis the first joint factor was formed, measuring the fat content and the meat content of the ham, as the analysis included the percentage of fat and the per- centage of meat in the ham. The result might have been different had the percentages been omitted from the analysis. It may also be mentioned that in the first factor the specific weight came as low as eighth with the loading —0.62. At Pohjanmaa the specific weight was determined on slaughterhouse scales that could only be read to an accuracy of 20 grams. In the Puistola material the scales could be read to an accuracy of s—lo g. For both materials, the follow- ing Table elucidates the correlation between the specific weight of the ham and the dis- section results on the ham and the most valuable part of the carcass. Fig. I. Dissection results in the six factors. 144 145 Table 3. The rotated loadings of the factors factor factor factor factor factor factor I II 111 IV V VI 1 Live weight, kg 23 —O3 46 04 46 30 2 Age days 09 —Ol —OO 31 —lO 15 3 Skin %of ham 18 —O4 —2l —B9 —Ol 11 4 Fat %of ham 93 12 —l2 —O2 —O2 —l9 5 Skin of ham 4* shank 18 22 15 —B6 —O7 10 6 Fat of ham + shank, g 52 82 13 —O2 —Ol —l6 7 Fat %of ham + shank 34 92 —OB —O3 —OO —l3 8 Skin + fat of shoulder, g 47 00 —l7 17 64 05 9 Skin + fat of ham, g 89 15 25 —l9 —O2 —2O 10 Skin + fat of most valuable part of carcass, g 80 03 08 —OB 49 —l9 11 Skin + fat of most valuable part, %of carcass 82 03 —l9 —l2 35 —2B 12 Meat %of ham —9O —O7 27 24 00 —O3 13 Specific weight of ham —62 —l4 17 —l9 02 19 14 Meat of hind shank —O6 01 54 —O4 —2l 31 15 Meat of ham 4- shank —3O —37 85 12 —OO —O6 16 Meat %of ham 4- shank —B2 35 29 22 00 —l3 17 Meat 4- bone of shoulder, g —3l —O7 20 08 50 20 18 Meat 4“ bone of hara, g —39 05 88 11 02 —O4 19 Meat 4- bone of most valuable part of carcass, g —4B 00 69 —OB 29 02 20 Meat 4- bone of most valuable part, %of carcass —7O —OO 23 -—l7 ■—os —l5 21 Bone %of ham —32 —l7 —2B —ll 09 74 22 Bone of hind shank, g —2B —O9 31 —22 06 70 23 Bone of ham 4- shank, g 06 99 06 02 01 13 24 Bone %of ham 4- shank —l5 98 —O6 —O6 02 08 25 Hind shank, g —O9 99 04 —O6 —Ol 03 26 Ham 4- shank, g 07 08 97 —Ol —Ol —O3 27 Most valuable part of carcass, g 09 02 69 —l2 59 —ll 28 Most valuable part, %of carcass —O4 03 10 —32 29 —46 Table 4. Phenotypical and genotypical correlations of ham, back and their skin + fat and meat + bone parts with the most valuable part of the carcass and its components (99 pigs from the Pohjanmaa testing station in 1967—68). X correlated with Y rphen. r, rgen. res. Ham most valuable part of carcass 0.67 0.62 0.68 Back most valuable part of carcass 0.67 0.76 0.65 Skin + fat of ham skin + fat of the most valuable part 0.72 0.79 0.700.72 0.79 0.70 Skin + fat of back skin + fat of the most valuable part 0.76 0.89 0.72 Meat + bone of ham meat + bone of the most valuable part 0.83 0.48 0.99 Meat + bone of back meat + bone of the most valuable part 0.66 0.52 0.690.52 0.69 Skin + fat of ham meat + bone of ham —0.14 —O.OO —0.23 Skin -f- fat of back meat -| ■ bone of back 0.06 0.04 0.07 Skin + fat component meat + bone component (of carcass) (of carcass) 0.06 0.14 0.11 146 Ham Most valuable part of the carcass skin -f- fat meat + bone skin + fat meat + bone Y, Y, Y, Y 4 Specific weight —0.79 0.33 —0.72 0.55 Puistola of the ham (X) —0.27 0.28 —0.37 0.34 Pohjanmaa —0.50 0.37 —0.46 0.30 Total The Table 1 shows that the accuracy of the scales at Pohjanmaa was not sufficient for the determination of the specific weights. The Puistola material established the great importance of the specific weight, of ham for measurement of the skin -(- fat part of the ham and skin -f- fat component of the most valuable part of the carcass. Owing to the testing technique there occurs a so-called auto-correlation in the results of the factor analysis as well as in other results of the dissection analysis based on correlation computations. This hardly reduces the serviceability of the results in breeding work, however. At the present stage of breeding there is no correlation worth mentioning between the skin + fat part of the ham and the meat + bone part of the ham (Puistola, r = —O.lB, Pohjanmaa, r = —0.00). Thus a decrease in the amount of fat in the ham does not necessarily imply a corresponding increase in the meat -)- bone part. Consequently, the present sudy aimed at measuring not only the fattiness of the ham but also the weight of its meat + bone component. This can be done because it is easy to detach the ham comparably from the carcass, and the ham can easily be separated into its skin -)- fat and meat -f- bone parts. The sales value of the carcass declines somewhat with this treat- ment. The cutting of the ham into two parts can also be advocated on the grounds that a knowledge of the skin + fat part of the ham provides rather a lot of information on the skin -f- fat component of the most valuable part of the carcass (Puistola, r = 0.76, Pohjanmaa, r = 0.74) and, similarly, the meat -)- bone part of the ham correlates very significantly with the meat + bone component of the most valuable part (Puistola, r = 0.83, Pohjanmaa, r = 0.81). It may be mentioned that according to Blendl (1966) a ham stripped of its fat correlated very significantly with the total quantity ofmeat obtained by complete dissection of the carcass; n = 116, r = 0.86. The respective phenotypical and genotypical correlation coefficients (Table 4) were generally of the same order of magnitude. An exception is the correlation of the meat + bone part of the ham with the meat + bone component of the most valuable part of the half carcass. (rphen = 0.83 and r s£n = 0.48). However, in this case too the genotypical correlation is held to be so high that the meat + bone component of the most valuable part of the carcass can be positively influenced by selecting for a large meat -f- -bone part of the ham. 147 REFERENCES Blendl, H. M. 1966. Objektive Methoden zur Bestimmung des Schlachtkorperwertes beim Schwein als Hilfsmittel fiir die zuchterische Selektion. Z-kunde 38: 234—246. Harman, H. H. 1960. Modern faktor analysis. 469 p. Chicago. Maijala, K. 1966. Repeatabilities and correlations of economic traits in the Finnish Random Sample egg-laying Test. Ann. Agr. Fenn. 5: 48—63. Uusisalmi, U. 1969 a. Vorläufige Ergebnisse iiber das Messen der Schlachteigenschaften beim Schwein. J. Sci. Agr. Soc. Finland 41: 50—59. —»— 1969 b. Carcass analysis as aid in pig breeding. Acta Agric. Scand. 19: 214—220. —»— 1971. Inheritance in ham and its components in Finnish Landrace and Yorkshire breeds. Acta Agr. Scand. 21: 73—83. Vahervuo, T. & Ahmavaara, Y. 1958. Johdatus faktorianalyysiin. WSOY, Helsinki. Varo, M. 1962. Über die Begrenzung der Beurteilungseigenschaften bei der Eberauslese. Ergebnis der Faktorenanalyse. Ann. Agr. Fenn. 1: 267—283. —»— 1965. Einige Beobachtungen iiber Anwendungsmoglichkeiten von Ergebnissen der Faktoren- analyse. Ibid. 4: 91—95. —»— 1966. Über den Zusammenhang der hei Pferden zu ziichtenden Ziige. Ibid. 5: 100—113. —»— 1968. Lampaiden kasvatuskokeiden tuloksia. Summary: Results of rearing trials with Finnish sheep. Ibid. 7: 33—45. SELOSTUS KINKUN TEURASLAATU JA SEN YHTEYS RUHON TEURASLAATUUN 11. KINKUN OMINAISPAINO JA LEIKKELY ANALYYSI Unto Uusisalmi Helsingin Yliopisto, Kotieläinten jalostustieteen laitos Kinkun teuraslaatua ja sen yhteyttä ruhon laatuun tutkittiin maatiais- ja yorkshirerotuisista kanta- koesioista Puistolan ja Pohjanmaan koeasemilla vuosina 1967 —68. Perinteellisen teurasarvostelun jälkeen ruhon puolisko paloiteltiin ja sen arvokkain osa leikattiin nahka + rasva- ja liha + luu-komponenteiksi. Kinkun ominaispainon määrittämisen jälkeen se leikattiin kudososiinsa; nahka, rasva, liha ja luut. Materiaalia (n = 200) käsiteltiin faktorianalyysin avulla. Ensimmäisessä faktorissa esiintyivät suu- rimmilla latauksilla kinkun rasva-% (0.93), kinkun liha-% (—0.90), kinkun nahka + rasvan paino (0.89) jaruhon arvokkaimman osan nahka + rasvan %-osuus (0.82). Lisäksi todettiin, että kinkun nahka+ rasva korreloitu! erittäin merkitsevästi ruhon arvokkaimman osan nahka -f rasvaan (Puistola, r = 0.76, Pohjanmaa, r = 0.74) ja kinkun liha -f- luu ruhon arvokkaimman osan liha -(- luuhun (Puistola, r = 0.83, Pohjanmaa, r = 0.81). Kinkun nahka + rasvan ja liha -f luun välillä ei todettu merkittävää korre- loitumista. Pohjanmaan materiaalilla (n = 99) todettiin kinkun ja kyljysselän sekä niiden komponenttien feno- tyyppinen ja genotyyppinen korreloituminen ruhon arvokkaimpaan osaan ja sen komponentteihin ver- rattain yhdenmukaiseksi. Poikkeuksen tästä muodosti kinkun liha -f luun korreloituminen ruhon arvok- kaimman osan liha -f luu-komponenttiin (rphen = 0.83, r gen = 0.48).