Among many farmers, butchers and consumers, the expectation is that meat arising from grazing cattle generally is darker than meat from cattle primarily fed cereals. Without necessarily being the truth, this dogma is a constraint to the marketing of ‘green’ meat. In an attempt to increase the supply of organic meat from young cattle, we need to know which quality parameters are the characteristics for this type of meat, including colour characteristics

Jensen, S.K.

Therkildsen, M.

Vestergaard, M.

English

Organic Eprints

2/2012 14Green veal is not dark red Margrethe Therkildsen1, Søren K. Jensen2  and Mogens Vestergaard21Department of Food Science and 2Department of Animal Science, Science and Technology, Aarhus University, DK-8830 Tjele, DenmarkMogens Vestergaard, e-mail: mv@agrsci.dkAmong many farmers, butchers and consumers, the expectation is that meat arising from grazing cattle generally is darker than meat from cattle primarily fed cereals. Without necessarily being the truth, this dogma is a constraint to the marketing of ‘green’ meat. In an attempt to increase the supply of organic meat from young cattle, we need to know which quality parame-ters are the characteristics for this type of meat, inclu-ding colour characteristics.Organic beef from young cattleThe organic rules require that bull calves are raised outdoor at least 6 months a year in Denmark and are fed at least 60% roughage of the total diet. These rules are a constraint for an organic production of beef based on the bull calves born in the organic dairy herds because of extra labor costs, expected lower growth rate, difficulties in raising bull calves outdoor, possibly lower meat quality and lack of sufficiently high organic premium payment for the carcass. Among the meat quality characteristics often considered to be compro-mised by grazing animals is meat colour, that among most people are thought to be darker compared with meat from animals fed a cereal-based ration.  As a consequence, bull calves born in the organic dairy herds are sold for conven-tional fattening. The supply of organic beef from young cattle is concomitantly very limited. However, in order to obtain the necessary higher payment for beef from organic-raised young cattle, it is important that consumers like the beef from grass- and herb-fed young cattle, as this is the primary feeds for organic meat-producing cattle.Experiment with young Holstein bulls calvesWe recently completed an experiment aimed at elucidating the effect of purely grass or herb feeding of Holstein bull calves for 8 weeks prior to slaughter at 9-10 months of age on meat colour, fatty acid composi-tion, vitamin content and eating quality of the meat in comparison with meat from traditional rosé veal calves fed a concentrate-based diet and slaughte-red at 9-10 months of age. Calves were housed in door in straw-bedded pens and fresh green feed was cut and brought to the barn every morning. After a 2-week adaption period, 6 bull calves were fed purely grass and 5 bull calves were fed purely herb-based green feed for 6 weeks prior to slaughter. All calves had free access to the feed, and the grass-fed calves ate 50 kg per calf per day of the mainly Perennial ryegrass sward, whereas the herbs-fed calves consumed 60 kg per calf per day. The major species in the herb sward was English plantain (56%), and White clover, Sainfoin, White melilot, Salad burnet and Yarrow each consti-tuted approximately 5% of the sward (table 1). As dry matter content and feeding value of the two swards were slightly different, the energy intake was similar on the two treatments. The growth rate was lower than for a traditional veal calf in this period and amounted to 1.0 kg per day for both grass- and herb-fed calves.At slaughter, meat from 6 traditionally concentrate-fed Holstein bull calves was also included in study. All calves were less than 10 months old at time of slau-ghter. We chose the young and lean veal calf for this study to avoid interference from the fatty tissue on taste and colour characteristics and focused the study on what happened in the mus-cle/meat. Carcass weights were 175 to 200 kg. No dark red meatThe lean/fat colour evalu-ated on the carcass showed a ‘normal’ colour score of all three treatment groups giving no evidence for the dogma that meat from grass-fed and herb-fed cattle turned dark. This was sup-ported by measurements of colour traits on both the loin (M. longissimus dorsi) and a thigh muscle (M. semi-membranosus) 2 days after slaughter on steaks bloomed in normal atmospheric con-ditions for 1 h at 4oC.  We assessed L* for lightness, a* for red/green colours and b* for yellow/blue colours, but found no differences between the three feeding strategies (table 2).  We have to keep in mind that these calves were only 10 months and the green-feeding was only offered for two months.2/2012 15No tenderness compro-miseThe loin and thigh muscles were aged (at 2 C) for additional 7 days, before sensory analysis by a trained panel. Steaks and roasts, respectively, were cooked and served for the panelists. Except for more meat flavor and juiciness in loin and less sweet aroma in the thigh muscle from herb-fed calves compared with grass- and concentrate-fed calves, there were no significant differences in the sensory profile. Further-more, a mechanical testing device that can measure the shear force to cut through the meat sample were also applied and showed a good ‘tenderness’ of the meat. In fact herb- and grass-fed meat from the thigh showed a better tenderness than meat from concentrate-fed calves.  These findings are important, because it seems unrealistic to increase the premium payment for orga-nic veal and beef (i.e., where grass and herbs constitute at least 60 % of the ration) if the sensory quality is not good. Healthy fat in herb- and grass-fed beefThe meat from herb-fed calves contained less oleic acid, and more lino-leic acid, α-linolenic acid, α-tocopherol and β-carotene compared with concentrate-fed calves and with grass-fed calves in between. The (n-6)/(n-3) ratio in the meat, which is considered important for the human diet, improved from 8.6 for concentrate-fed  to 4.6 and 5.3 for herb- and grass-fed calves, respectively. Despite this positive effect, we have to remember that these calves only contained 1-2% of intramuscular fat in the loin, so the real benefit from the ‘improved’ fatty acid composition is probably not large.Marketing potentialOverall, the study showed that green-feeding for a 2-months period prior to slaughter can improve fatty acid composition and vita-min content, produce tender meat with a good flavor and with no signs of a darkening of the meat. All facts are im-portant for the marketing of veal and beef from organic raised cattle.AcknowledgementsThis project is part of the Organic RDD program, which is coordinated by International Centre for Research in Organic Food Systems, ICROFS. It is fun-ded by The Danish AgriFish Agency, Ministry of Food, Agriculture and Fisheries and by Aarhus University. Danish Crown is acknow-ledged for excellent support at sampling of muscles and Jens Askov Jensen, Aarhus University for excellent technical assistance.  2/2012 16Name              Latin name Grass Herbs                                                                                          % in swardEnglish plan-tainPlantago lanceo-lata56.4Salad burnet Sanguisorba minor4.6Sainfoin Onobrychis viciifolia6.1White melilot Melilotus alba 5.7Yarrow Achillea millefo-lium3.9White clover  Trifolium repens 2.4 4.3Perennial ry-egrassLolium perenne 83.6 0.7Weeds 14.0 18.4Table 1 Composition of grass and herb swards fed to the calvesFeeding             Grass Herbs Con  P-value Number of calves 6 5 6Age at slaughter, days 299 299 < 305 nsADG (6 wks), g/d 987 969 ~1250 nsLive weight at slaughter, kg 363 365 ~390 nsCarcass weight, kg 178 185 197 0.10Dressing, % 49.0 50.7 ~ 50.5 0.09EUROP conformation 2.7b 2.9b 3.7a 0.004EUROP fatness 1.7 1.8 2.2 nsLean/fat colour 3.0 2.8 3.0 nsL* loin 32.5 31.8 31.5 nsa* loin 14.2 14.9 13.4 nsb* loin 5.7 5.8 5.3 nsTable 2  Performance and carcass quality of bull calves fed either purely grass (Grass) or herb-based green feed (Herbs) compared with concentrate-fed bull calves (Con)ns: Non significant.  a b numbers with different superscript are significantly different. Numbers in gray are estimated

Green veal is not dark red

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