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   PLEASE SCROLL DOWN FOR ARTICLE This article was downloaded by: [Danmarks Vet & Jordbrugsbibliotek]  On: 14 January 2011 Access details: Access Details: [subscription number 915637824]  Publisher Taylor & Francis  Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK British Poultry Science Publication details, including instructions for authors and subscription information: The effect of breed and feed type on the sensory profile of breast meat inmale broilers reared in an organic free range system K. Horsted a ; B. H. Allesen-Holm b ; J. E. Hermansen aa  Department of Agroecology and Environment, Aarhus University, Faculty of Agricultural Sciences,DK-8830 Tjele, Denmark b  Department of Food Science - Sensory Science, University of Copenhagen,Faculty of Life Sciences, DK-1958 Frederiksberg C, DenmarkOnline publication date: 30 September 2010 To cite this Article  Horsted, K. , Allesen-Holm, B. H. and Hermansen, J. E.(2010) 'The effect of breed and feed-type on thesensory profile of breast meat in male broilers reared in an organic free-range system', British Poultry Science, 51: 4, 515— 524 To link to this Article: DOI: 10.1080/00071668.2010.506907 URL: Full terms and conditions of use: article may be used for research, teaching and private study purposes. Any substantial orsystematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply ordistribution in any form to anyone is expressly forbidden.The publisher does not give any warranty express or implied or make any representation that the contentswill be complete or accurate or up to date. The accuracy of any instructions, formulae and drug dosesshould be independently verified with primary sources. The publisher shall not be liable for any loss,actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directlyor indirectly in connection with or arising out of the use of this material.   British Poultry Science  Volume 51, Number 4 (August 2010), pp. 515 — 524 The effect of breed and feed-type on the sensory profile of breast meatin male broilers reared in an organic free-range system K. HORSTED, B.H. ALLESEN-HOLM 1 AND  J.E. HERMANSEN  Department of Agroecology and Environment, Aarhus University, Faculty of Agricultural Sciences, PO Box 50, DK-8830 Tjele, Denmark, and  1  Department of Food Science – Sensory Science, University of Copenhagen, Faculty of Life Sciences, Rolighedsvej 30, Floor 5, DK-1958 Frederiksberg C, Denmark  Abstract  1. Studies on the sensory profiling of male broiler breast meat were carried out to evaluatethe effect of two very different broiler breeds (JA757 and New Hampshire), two different feed types(broiler and grower feed) and age at slaughter (82 and 110d).2. The sensory profiling consisted of a pilot study, 4 training sessions, and finally the assessment.During the training session a panel of 9 assessors defined 17 attributes, which were used to describe thesmell, texture and flavour of the breast fillets. Each attribute was evaluated on a 15-cm unstructured linescale.3. The breast meat became significantly less hard, and more juicy and tender in the New Hampshire at110d of age, whereas the opposite was found in JA757, which also acquired a more ‘‘sourish’’ flavourwith age. The smell of ‘‘sweet/maize’’ and ‘‘bouillon’’ became weaker with age in JA757, but not in NewHampshire.4. Several significant differences in relation to the main factors of breed and age were found. Thetraditional broiler hybrid JA757 did best for most smell and flavour attributes, whereas New Hampshiredid best for the texture attributes. Age had a negative effect on the flavours and smell attributes ‘‘freshchicken’’, ‘‘neck of pork’’ and ‘‘sweet maize’’, but a positive effect on the texture attribute ‘‘crumbly’’.In addition meat was more ‘‘stringy’’ at 110d of age.5. The flavours ‘‘neck of pork’’ and ‘‘umami’’ were significantly improved when JA757 was fed on thebroiler feed and when New Hampshire was given the grower feed. The meat smelt more ‘‘sourish’’at 82d of age and less ‘‘sourish’’ at 110d of age when the grower feed was consumed. Meat wassignificantly harder and stringier when JA757 was fed on the grower feed. This was not the case for NewHampshire. In general, the meat was significantly less crumbly and stringier with the grower feed.6. Overall a very distinct difference in sensory profile was found between the two breeds. In additiondifferent slaughter ages and feeding strategies should be taken into consideration in a niche productionbased on alternative genotypes. INTRODUCTION Even though the principles behind organicproduction include ethical considerations(IFOAM, 2000), organic poultry production is tosome degree based on the same rationale as theconventional poultry industry,  i.e.  highly specia-lised layer and broiler breeds that need to beproduced in large flocks to obtain a satisfactoryeconomic output. For organic egg production,one of the consequences is that male chickens arekilled just after they have been hatched. This isdone since male chickens from layer breeds areconsidered as having no economic value due toslow growth, low meat production, low feedconversion rate, and different carcase conforma-tion. However, from an organic/ecological per-spective this is considered as a huge image Correspondence to: Klaus Horsted, Aarhus University, Faculty of Agricultural Sciences, Department of Agroecology and Environment, Box 50,DK-8830 Tjele, Denmark. E-mail: Klaus.Horsted [a] agrsci.dkAccepted for publication 10th February 2010. ISSN 0007–1668(print)/ISSN 1466–1799 (online)/10/040515 — 10    2010 British Poultry Science LtdDOI: 10.1080/00071668.2010.506907  D o w nl o ad ed  B y : [ D a n m a rk s  V e t  &  J o rdb r u g sbibli o t ek]  A t : 08 :02 14  J a n u a r y 2011    A  r  c   h   i  v  e   d  a  t   h  t  t  p  :   /   /  o  r  g  p  r   i  n  t  s .  o  r  g   /   1   8   2   1   2  problem and can lead to less consumer supportfor organically produced poultry products. As analternative to the traditional organic egg andbroilerproduction,anicheproductionbasedona combined production of eggs and meat might beconsidered. This may involve the reintroductionof the so-called dual-purpose breeds that werewidespread in the time before industrialisation(Robinson, 1961).Inrelation totheproductionof broilers, the slower growing, dual-purpose breedsmay even be better suited to a dual role incombination with other branches of production, e.g.  as pest controllers in fruit production(Clark and Gage, 1996; Pedersen  et al  ., 2004),since slow-growing broilers have proven moreactive in the outdoor run than fast-growingbroilers (Bokkers and Koene, 2003; Nielsen et al  ., 2003). However, even if the males from a dual-purpose breed are expected to have a highermeatproductionthanmalesfromtraditionallayerstrains, it is still less than traditional organicbroiler hybrids (Horsted  et al  ., 2005). Therefore,other quality dimensions must be considered inorder to obtain a premium price for slow-growingbroilers. Besides the ethical aspect, this could be a superior sensory quality of the meat from dual-purpose breeds. Several studies have identifieddifferences in sensory meat quality in traditionalbroiler hybrids (Lawlor  et al  ., 2003; Jahan  et al  .,2005; Brown  et al  ., 2008), but very little has beenpublished in relation to old dual-purpose breedsand to slaughter ages close to sexual maturity(Horsted  et al  ., 2005). Further, the feedingstrategy required to obtain good sensory qualityin meat from old breeds still needs to beexamined.With this background, the objective of thepresent study was to test for distinct differencesin the sensory profile of breast meat from malesfrom a dual-purpose breed and males from a relatively fast-growing broiler hybrid, andwhether this was influenced by feed type andage at slaughter. MATERIALS AND METHODS Breeds and rearing of experimental broilers A New Hampshire dual-purpose breed wasselected from the small hatchery ‘‘Hellevad’’ inDenmark where the New Hampshire is used as a female parent to produce a robust layer strain forthe organic market. The JA757 from the‘‘Hubbard Breeders’’ company was chosen torepresent a faster growing conventional broilerhybrid. This hybrid was chosen because it hadbeen selected for the organic broiler market afterthe regulations for organic broiler production inDenmark had been modified (The Danish PlantDirectorate, 2008).The chicks were hatched on the same dayand reared for the first 39d by an organicproducer. All broilers were reared togetherduring this period and from one week of agethey were given access to an outdoor area withfruit trees for two 1-h periods daily. They werefed on a normal commercial starter diet with210g/kg crude protein for the first 3 weeks, andfrom 3 weeks of age until the introduction to theexperiment at 39d of age they were given a broiler feed (Table 1). Experimental design and recordings on livebroilers On 15 May 2007 (at 39d of age), the broilerswere allocated to the experiment, which tookplace in a research orchard with apple trees. Thebroilers were divided into 12 flocks with47 broilers in each flock (6 flocks with the NewHampshire breed (3/4 were males) and 6 flockswith the JA757 hybrid (half were males)). Withineach breed, three flocks were fed on a commer-cially produced broiler compound feed, andthree flocks received a compound feed forgrowers. The broiler feed usually has a relativelyhigh crude protein content (190g/kg) and isbased on maize, whereas the grower feed is lowerin crude protein (160g/kg) and is mainly basedon wheat with fishmeal as an important proteinsource. However, analyses suggested a highercontent of crude protein in the grower feed thanstated by the formula (Table 1). These feed typeswere chosen for the experiment since the broilerfeed and grower feed were the preferred feedsfor JA757 and New Hampshire, respectively.Besides, both feed types are on the market andtherefore easy to procure in practice.Average weights at the beginning of theexperiment were 1423 and 569g for JA757 andNew Hampshire, respectively. Each pen mea-sured approximately 30  15 m and containedapproximately 110 apple trees,  i.e.  each broilerhad approximately 9  5 m 2 outdoor area.The broilers had access to a chicken house withperches, but feed and water were allocated in theoutdoor area under a rain shield to motivate thebroilers to go outside. The feeding silos werefilled as required,  i.e.  approximately twice a week.Feed consumption was recorded for each pen byweighing the allocated feed and weighing whatwas left in the silos on the days of slaughter at 82and 110d of age.Half of the broilers were slaughtered at 82dand the rest at 110d of age. Ages of slaughterwere chosen according to the French  Label Rouge concept (, 2008) and theDanish regulation for organic broiler production(The Danish Plant Directorate, 2008). Thelatter distinguishes between fast and 516  K. HORSTED  ET AL.  D o w nl o ad ed  B y : [ D a n m a rk s  V e t  &  J o rdb r u g sbibli o t ek]  A t : 08 :02 14  J a n u a r y 2011  slow-growing broilers, with fast-growing broilershaving an age of slaughter of at least 81d,whereas slow-growing broilers can be slaughteredat 70d of age unless the brood eggs are organic,when there is no age limit. The definition of a slow-growing broiler is daily weights gain notexceeding 35g/d.In the present study all broilers wereweighed at 60, 82 and 110d of age. At 82d of age samples from the cloacae of 10 randomlychosen broilers from each of the 12 pens weretaken and analysed for salmonella. Samples fromeach pen were pooled,  i.e.  a total of 12 sampleswere analysed. Slaughtering of broilers A sample of 6 male broilers from each plot wererandomly selected for sensory assessment,  i.e. 18 broilers from each treatment. The broilerswere caught in the late evening and transportedin crates to the slaughterhouse during the night(1 h of transport) and slaughtered in the earlymorning. After the broilers had been slaughteredand bled, the carcases were scalded in water attemperatures of 58 — 61  C depending onbreed. Feathers were subsequently removed ina plucking machine. The carcases were thenplaced in a vat with cooling water and sub-sequently eviscerated and hung up in a coldstorage room at a temperature at 4  C decreasingto 1  C. The carcases were kept in cold storage fornot less than 24 h and afterwards frozen to  18  C. After a few days, the carcases weretransported in a refrigerated van to the SensoryLaboratory at the University of Copenhagen,Department of Food Science. Sensory assessment Cooking and serving of samples Prior to the sensory profiling, the carcases werethawed in a controlled-temperature chamber at4  C for 30 and 24 h for JA757 and NewHampshire, respectively, due to different carcaseweights. Subsequently the breast fillets were cutoff and weighed to determine the cooking time,which was arranged so the fillets had a coretemperature of 75  C. The fillets (with skin) werecooked in pre-heated hot-air ovens at 185  C.The fillets were subsequently cut into 5 pieces,ensuring that each assessor in the panel receivedthe same part (sample) of the fillet for eachassessment (ASTM, 2006). Table 1.  Ingredient and nutrient contents of the experimental diets  Ingredient (g/kg):  Broiler feed,pelletedGrower feed,pelletedMaize, organic 360  7 0Wheat, organic 250 500Barley, organic 0 150Soya cake toasted, organic 200 92  5Sunflower cake, organic 120 120Oat, organic 25 50Greenmeal, organic 0 30Fishmeal 0 30Mono calcium phosphate 12  5 8  2Calcium carbonate 12  2 13  3Biotin premix 9  5 0Rape seed oil 3 0Rock salt 2  6 2  6 Vitamin premix 2  5 2  5Sodium bicarbonate 1  5 0  7Bergazyme(Endo-1  4-beta-xylanase3  2  1  8. EF no.: E1617)0  3 0Betain anhydrate 0  2 0  2  Nutrient content (g/kg):  Formula Analysis Formula AnalysisCrude protein 190 192 160 182Crude fat 59 58 45 49Starch Not stated 383 Not stated 363Sugar Not stated 33 Not stated 28Cellulose 52 Not analysed 69 Not analysedCrude ash 61 Not analysed 55 Not analysedLysine 8  9 8  1 7  5 7  9Methionine 3  4 3  1 3  0 3  2Cystine 3  5 3  2 3  0 3  2Threonine Not stated 7  1 Not stated 6  8ME (MJ/kgDM) Min 12  00 11  79 Min 11  10 10  93 SENSORY PROFILE OF BROILER MEAT  517  D o w nl o ad ed  B y : [ D a n m a rk s  V e t  &  J o rdb r u g sbibli o t ek]  A t : 08 :02 14  J a n u a r y 2011
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