Garganica kid goat meat: Physico-chemical characterization and nutritional impacts

Journal of Food Composition and Analysis 28 (2012) 107–113

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Original Research Article

Garganica kid goat meat: Physico-chemical characterization and nutritional impacts F. Longobardi a, D. Sacco a, G. Casiello a, A. Ventrella a, A. Contessa b, A. Sacco a,* a b

Dipartimento di Chimica, Universita` di Bari ‘‘A. Moro’’, Via Orabona 4, 70126 Bari, Italy Societa` AGRIFAP Srl, Viale del Lavoro 45, 37036 San Martino Buon Albergo, Italy

A R T I C L E I N F O

A B S T R A C T

Article history: Received 18 January 2012 Received in revised form 12 July 2012 Accepted 1 August 2012

A detailed physico-chemical characterization of the Garganica kid goat meat was carried out on samples (quadriceps femoris muscles) coming from different farms located on the Promontory of Gargano, in Apulia (southern Italy) by determining conventional parameters (moisture, ashes, fat, and protein content), stable isotope ratios (15N/14N and 13C/12C), major (Ca, Mg, Na, and K), and trace metals (Zn, Mn, Cu, Fe, and Cr). Moreover, information on a large number of metabolites was obtained by means of 1H High-Resolution Magic-Angle Spinning Nuclear Magnetic Resonance (1H HR-MAS NMR) spectroscopy. The most interesting findings of this work, for their impact on human nutrition and health, were represented by a considerable protein content (18.9%) and a low fat content (2.98%), characterized by a remarkable average percentage of desirable fatty acids (62.76%) and a good (C18 + C18:1)/C16 average ratio (2.30), that make the Garganica kid goat meat a highly appreciable food product. ß 2012 Elsevier Inc. All rights reserved.

Keywords: Garganica kid goat meat characterization Conventional analyses Metal content Innovative techniques 1 H HR-MAS NMR Stable isotope ratios Biodiversity and nutrition Livestock management and nutrition Food analysis Food composition

1. Introduction Food represents not only the satisfaction of nutritional demands but also an ideal of well-being. In addition, meat demand is becoming more oriented toward fresh, high quality products. It is known that the concept of food quality is not univocal, and that it involves both nutrition and aspects related to appeal and appreciation; consequently, the term ‘‘meat quality’’ is a rapidly changing concept, generically used to describe properties and perceptions of meat (Bredahl, 2003; Maltin et al., 2003), involving characteristics such as carcass composition and conformation, eating quality, health and production-related issues (Maltin et al., 2003), communication around the product, and combination of these (Banovic et al., 2009, 2010). Another important aspect related to the quality of European fresh meat is its geographical origin, and, in fact, a regulation of the European Community obliges beef producers to indicate the origin of the meat on the labels allowing to trace the entire route of the meat products from farm to table (Bernue´s et al., 2003). These labels must indicate where the animal was born, where it was reared, where it was slaughtered and the place where the meat was

* Corresponding author. E-mail address: [email protected] (A. Sacco). 0889-1575/$ – see front matter ß 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jfca.2012.08.007

butchered (Costa et al., 2008; Renou et al., 2004). Considering these factors, it is clear that studies on the factors affecting the perception of meat quality are interesting not only from a scientific point of view, but also for relevant economic implications. Recently, investigations have been made on different compositional parameters which could be related to feeding and geographical origin of meat products. It is well accepted that diet and the site where the animals are raised influence the isotopic composition of water, fat and protein of their tissues and derived products. Therefore, the analysis of the stable isotope composition by means of Isotope Ratio Mass Spectrometry (IRMS), gives pertinent information on the animal’s diet and on the geographical origin of meat. However, it should be noted that animals may consume mixed diets and undergo changes in the nature of their diet, together with changes in their geographical location, all issues that may make the use of such markers more complex. The correlation between 18O and 2H content of water consumed by animals and 18O and 2H content of organic compounds present in animal products, such as butter and cheese, has already been found (Manca et al., 2001; Rossmann et al., 2000). Piasentier et al. (2003) found that the ratios of stable isotopes of bioelements, such as C and N, could be successfully used to check the geographical origin of meat products. In fact, significant differences in d13C values of protein and fat and in d15N values of protein fractions of lamb meats

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coming from different countries and feeding regimes were found. Heaton et al. (2003) demonstrated also that isotope ratios of heavy elements such as Sr could carry information about meat geographical origin, because they are correlated to Sr content in rocks and their geological age. Low resolution Nuclear Magnetic Resonance (NMR) spectroscopy has demonstrated to be a useful tool for the assessment of meat quality and authenticity. Water retention capacity of fresh meat, which is related to water exudation, was assessed by NMR relaxation measurement of water protons (Offer and Knight, 1988). Magnetic Resonance Imaging (MRI) permitted the detection of the distribution of connective tissue, on which the toughness of meat and fat depends (Bonny et al., 2001). MRI was also used to distinguish between fresh and frozen/thawed products (Foucat et al., 2001). High field (500 MHz) NMR was applied for authenticity purposes, in particular to highlight adulteration through the combination of different meat cuts (Al-Jowder et al., 2001). The advantage of this approach consists in the high quantity of information contained in the NMR spectrum that can be regarded as the fingerprint of the sample. For authenticity purposes a high number of samples should be analyzed in order to compare the spectra of authentic and adulterated samples. Since high resolution NMR spectra contain many signals, a visual comparison is not easy and to deal with this problem chemometric methods need to be applied. The potential application of these methods to NMR data has been investigated in food analysis (Belton et al., 1998; Vogels et al., 1996; Zamora et al., 2002). Moreover, chemometric methods were also successfully applied on FT-IR spectroscopic data for compositional profiling and classification of food samples (Kemsley et al., 1996). Recently, among the different meat productions, particular attention has been focused on the production of goat meat. In particular, the kid goat meat is becoming increasingly important economically; this can be attributed both to a strong demand and to an interest in ecologically sound forms of vegetation control (https://attra.ncat.org/attra-pub/meatgoat.html). Kid goat meat is a pale pink color and, compared to adult goats or to bovine specimens, can be considered a lean, tender meat with a fine grain (Santos et al., 2007). It is particularly appreciated by consumers because it is a tasty meat that has a pleasant milky odor, and it is highly nutritious and easily to digest. Goat meat that is produced by rearing animals under extensive management is an expensive food product usually consumed only at special times during the year, such as Christmas and Easter. In the present work, samples of kid-goat meat belonging to the autochthonous Garganica breed and coming from a restricted and characteristic production area in the Promontory of Gargano (located in Apulia, southern Italy) were analyzed by means of different methods. In particular, conventional analyses (moisture, ashes, fat and protein content), Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), High Performance Ion Chromatography (HPIC), 1H NMR HR-MAS and IRMS were used with the aim to achieve a preliminary characterization of the chemical and physical characteristics of kid-goat meat.

remarkable dimensions allowed supplying the largest number of milk suckling goats. Regarding the feeding of animals, pregnant goat does were fed extensively, at pasture. The kids were reared according to the traditional farming system for Gargano kid goats: they were exclusively milk-fed, sucking from the dams until they reached the usual commercial live weight of 9.7  0.7 kg, specifically until the time of slaughter, which occurred around the age of 40–50 days. Suckling occurred twice daily, in the morning at about 7:00, before taking the dams out to pasture, and in the evening at about 19:00 when the dams came back from pasture. The contact with the dams was limited to the time necessary for complete suckling of the breast milk, and thereafter the kids were separated from their mothers to be put into pens, where they remained until going out again for the next feed. The weight of the kid was about 3.5 kg at birth. The daily weight increment of the kid during the first month after birth was 150–160 g. The slaughter was carried out according to the dictates of the Community legislation in force. For the analyses, each carcass was taken to the laboratory under normal refrigeration conditions. The rear leg muscles were cut in the region of the thigh into small portions. Immediately after their collection all samples were minced with a mincer machine, freeze-dried and stored in polypropylene bottles at 80 8C in a freezer until analysis. Each package was given an identification number corresponding to that of the carcass. 2.2. Conventional analyses The moisture content was obtained measuring the weight difference before and after the heating in stove for 5 h to 102 8C and the ash content was obtained by heating the dry sample to 600 8C. Fat content was measured by extraction with petroleum ether in a Soxhlet apparatus and protein content with the Kjeldhal method. 2.3. Metal determinations Fe, Mn, Cr, Cu and Zn concentrations were determined by using an inductively coupled plasma atomic emission spectrometer VARIAN model ICP-AES Liberty 110 (VARIAN Inc., Palo Alto, USA) equipped with a vertical torch and an ultrasonic nebulizer CETAC model U-5000AT+ (CETAC Technologies Inc., Omaha, NE, USA). Before analysis, the samples were freeze-dried and subjected to a mineralization process: 0.8 g of sample were dissolved in 10 ml of 70% HNO3 ULTREX (J.T. Baker, Phillipsburg, USA) and 2 ml of 30% H2O2 (J.T. Baker, Phillipsburg, USA) and they were digested in a microwave system Milestone model MLS-1200 MEGA (Milestone, Bergamo, Italy). Na, K, Mg and Ca contents were measured by means of high performance ion chromatography (HPIC, DX 120 EX, Dionex, Sunnyvale, CA, USA), equipped with a conductometric detector, following the procedure described in a previous paper (Brescia et al., 2002a). For these determinations, meat ashes were dissolved in 5 ml of 1 M HCl. For the freeze-dry process of goat meat, a Heto-Holten A/S LyoLab 3000 instrument was used, connected with a vacuum rotary pump. The freeze-dry process was performed at 55 8C.

2. Materials and methods 2.4. Fatty acid composition 2.1. Kid goat meat Ten male samples (i.e., 10 different animals) of Garganica purebred were supplied by 10 farms located in the delimited territory of Gargano in the northeast part of Apulia, in southern Italy. These farms are highly representative of the territory since they are traditionally devoted to the rearing of goats under extensive management in the wild, and most of all because their

The fatty acid composition of goat meat samples was determined by gas chromatography (GC) as fatty acid methyl esters (FAME). The methodology involves the alkaline saponification of extracted fat to break down their glycerides, and for the subsequent esterification of the liberated FAs in the presence of methanol solution. The formed FAMEs are then extracted with organic solvents and analyzed by GC with flame ionization detector (FID).

F. Longobardi et al. / Journal of Food Composition and Analysis 28 (2012) 107–113

Briefly, meat samples were saponified for 30 min in the water bath at 60–70 8C with the methanolic solution of KOH (2 mol/l). Methyl esters of fatty acids were separated and quantified by using a HR-GC, Carlo Erba gas chromatograph, equipped with a DB Waxtype analytical column, (30 m length  0.32 mm i.d.) coated with 0.5 mm film thickness (100% PEG, polyethylene glycol) (J&W Scientific Inc., Rancho Cordova, CA, USA), and coupled with an FID detector (Varian, Middelburg, The Netherlands). Helium was used as the carrier gas. The injection is performed with a split ratio 1:50 and constant flow operating mode at 50 m/s. The injector temperature and the heated block temperature are both set at 220 8C. The injected volume was 1 ml. Fatty acids were identified by comparison with retention times of fatty acids in standard samples. 2.5. Stable isotope ratio analysis Measurement of the 13C/12C and 15N/14N ratios (d13C and d15N, respectively) of the whole goat muscle was carried out on the freeze-dried samples. About 1.5 mg of sample were directly weighed into tin capsules for these determinations. The analyses were performed using an isotopic ratio mass spectrometer (IRMS, Finnigan Delta V Advantage, Thermo Fisher Scientific, Bremen, Germany) coupled with an Elemental Analyser (EA, FlashEA 1112 HT, Thermo Fisher Scientific, Bremen, Germany). The EA was equipped with a combustion reactor for determination of 13C/12C and 15N/14N. The EA was connected with an autosampler (MAS 200R, Thermo Fisher Scientific, Bremen, Germany) and interfaced with the IRMS through a dilutor (Finningam, Conflo III, Thermo Fisher Scientific, Bremen, Germany) dosing the samples and reference gases. Variations in stable isotope ratios were reported as parts per thousand (%) deviation from Internationally accepted standards: Pee Dee Belemnite (PDB) for carbon, atmospheric nitrogen (AIR) for nitrogen. The isotopic values were expressed using the formula:

d ð%Þ ¼

  Rsample  Rstandard Þ  1000 Rstandard

where R is the ratio between the heavy and light isotopes, Rsample is the isotopic ratio of the sample and Rstandard is that of the reference material. Each sample was analyzed twice and values were averaged. The analysis was repeated if the difference between the two values was higher than 0.2% for d15N and d13C, respectively. The values were referenced against reference gases (N2 and CO2) previously calibrated against International Standards from International Atomic Energy Agency (IAEA). Moreover, for each run at least one in-house standard (casein for both carbon and nitrogen) was analyzed to check the accuracy of the analysis. 2.6. NMR determinations 30 mg of D2O was added to 40 mg of the freeze dried sample, according to the procedure described by Brescia et al. (2002b). The obtained semi-solid pulp was inserted in the rotor for the 1H High Resolution Magic Angle Spinning (HR-MAS) NMR analysis. The NMR spectrum of the semi-solid meat sample was obtained with a Bruker AVANCE 500 MHz NMR spectrometer (Bruker Analytik GmbH, Rheinstetten, Germany) equipped with a HR-MAS probe head. The samples were brought to the magic angle (548440 ) with respect to the direction of the static magnetic field and spun at 4500 Hz in order to minimize the chemical shift anisotropy effects. Spectra were acquired with water signal suppression by presaturation. The following experimental conditions were applied: spectral width = 7000 Hz (12 ppm); time domain = 32 K

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points; number of transients = 128. Spectra were processed by applying a 0.3 Hz line broadening factor. Fourier-transformed spectra were phased and then the baseline corrected by spline interpolation of 14 baseline selected points. 3. Results and discussion The results of conventional analyses carried out on the ten goat meat samples are reported in Table 1. An average fat content value of 3% was found according to the values of fat content of about 2.5–5% for the kid goat reported in the literature (Atti et al., 2006; INRAN, 2009; Mahgoub et al., 2002; Webb et al., 2005). Moreover, it should be noted that in 5 of these latter, a value of less than 2% was measured. These results could be explained considering that the analyzed samples came from kid goats reared only on milk under the dam, and slaughtered very young at 40–45 days of age, when the intramuscular fat deposition process is still limited. This is a favorable feature that makes kid goat meat particularly appreciated from the health-conscious consumers. Generally, the fat content influences the organoleptic properties and the quality of meat, even if, as reported in Section 1, the term ‘‘meat quality’’ is a broader concept connected to consumer quality perception. The protein average value found (18.9%) is in good agreement with the data reported in the literature (19.2%) (INRAN, 2009). At this respect, goat meat can be considered a good source of proteins with high biological value. Also the moisture average value found (75.8%) is not very dissimilar to that reported in the literature (74.8%) (INRAN, 2009). 3.1. Fatty acid composition A description of the fatty acid profile (Table 2) is reported in the following paragraphs. In accordance with previous studies (Todaro et al., 2002), the major saturated fatty acids (SFA) identified in the intramuscular adipose tissue were palmitic acid (C16:0) and stearic acid (C18:0), while oleic acid (C18:1) was the main unsaturated fatty acid (UFA). Polyunsaturated fatty acids (PUFA) consisted largely of linoleic acid (C18:2), linolenic acid (C18:3) and arachidonic acid (C20:4). The proportions of the fatty acids were in the typical range for ruminants (Atti et al., 2006; Banskalieva et al., 2000; Bas et al., 2005; Beserra et al., 2004; Tshabalala et al., 2003). The results of this study are particularly consistent with data reported by Brzostowski et al. (2008), where the same muscles considered herein (quadriceps femoris) were studied. In particular, the C18:1 had the highest percentage compared to the other determined fatty acids. Rhee et al. (2000) reported that oleic acid constituted more than two-thirds of UFAs in intramuscular fat from crossbred goats, as confirmed by data reported herein. Nevertheless, the values recorded for C18:0 and C18:1, in Table 1 Chemical composition (%) of Garganica kid goat meat samples. Sample 1 2 3 4 5 6 7 8 9 10 Mean SD

Ashes

Moisture

Proteins

1.11 1.19 1.19 1.12 1.07 1.03 1.08 1.18 1.07 1.14

77.5 77.7 77.0 76.4 75.3 71.2 74.9 77.5 73.1 77.2

19.4 17.1 19.7 19.0 19.1 18.8 18.9 17.5 19.9 20.0

Fat 1.70 1.17 1.37 3.08 4.29 5.83 4.68 1.22 5.07 1.45

1.12 0.06

75.8 2.2

18.9 1.0

2.98 1.83

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Table 2 Fatty acid composition (%) of Garganica kid goat meat.

C10:0 C12:0 C14:0 C16:0 C16:1 C18:0 C18:1 C18:2 C18:3 C20:4 others SFA MUFA PUFA PUFA/SFA DFA (C18:0 + C18:1)/C16:0

1

2

3

4

5

6

7

8

9

10

Mean

SD

1.17 2.15 11.80 25.70 2.87 13.70 37.70 2.75 1.08 0.93 0.15 54.52 40.57 4.76 0.09 59.03 2.00

1.20 2.44 13.20 30.20 3.86 11.30 32.60 3.53 0.95 0.51 0.21 58.34 36.46 4.99 0.09 52.75 1.45

0.89 1.98 11.40 28.80 3.91 13.00 35.60 3.19 0.80 0.20 0.23 56.07 39.51 4.19 0.07 56.70 1.69

1.58 2.98 11.43 19.72 5.51 12.74 41.02 2.83 0.84 1.16 0.20 48.43 46.53 4.84 0.10 64.11 2.73

0.36 0.89 10.33 17.21 5.26 13.15 43.64 5.38 2.27 1.25 0.26 41.93 48.90 8.91 0.21 70.96 3.30

1.09 1.22 10.80 20.30 5.51 22.84 34.64 1.78 0.60 1.05 0.18 56.25 40.15 3.43 0.06 66.41 2.83

0.26 1.25 11.95 22.60 8.52 11.65 39.23 2.65 0.48 1.21 0.19 47.71 47.75 4.34 0.09 63.74 2.25

0.23 0.96 10.88 20.74 8.22 13.66 36.92 5.96 0.75 1.53 0.16 46.46 45.14 8.23 0.18 67.03 2.44

0.22 1.56 11.89 22.39 5.70 12.95 37.76 5.57 1.03 0.79 0.15 49.01 43.46 7.38 0.15 63.80 2.26

0.90 1.03 10.67 24.10 6.33 13.65 36.21 5.16 0.15 1.57 0.23 50.36 42.53 6.89 0.14 63.07 2.07

0.79 1.65 11.43 23.18 5.57 13.86 37.53 3.88 0.90 1.02 0.20 50.91 43.10 5.80 0.12 62.76 2.30

 0.49 0.71 0.83 4.09 1.81 3.26 3.18 1.49 0.56 0.43 0.04 5.21 4.00 1.89 0.05 5.31 0.55

this study, were often lower than those obtained by other authors (Dhanda et al., 2003; Werdi Pratiwi et al., 2007), probably due to the use of different breed, feed and slaughter weight: indeed, a change in the diet after weaning and the consequent increase in the slaughter weight will change significantly the fatty acid profile. Moreover, such difference could also be related to the different lipogenic activity of the enzymes at the level of the different muscles, as reported by Banskalieva et al. (2000). The fatty acid profile in suckling kids, which are pre-ruminants, is related to the composition of the maternal milk, that is naturally rich in short-chain fatty acids (Osorio et al., 2007; SanzSampelayo et al., 2007). Nevertheless, young animals, kid goats included, hardly accumulate short chain fatty acids in the adipose tissue (Banon et al., 2006) as confirmed by the absence of short chain (C4–C8) fatty acids in samples analyzed herein. On the other hand, the traditional rearing system adopted in this work, rich in long chain fatty acids, can explain the presence of such FA signals in the analyzed kid meat (Horcada et al., 2012). A typical fatty acid of green forage is the C18:3 that are not synthesized by mammals. Generally it is accepted that, higher concentrations of long chain SFAs raises plasma cholesterol, while higher concentrations of monounsaturated fatty acid (MUFA) and PUFA will decrease it (Grundy and Denke, 1990; Ulbricht and Southgate, 1991; Williams, 2000). Nevertheless, recent studies have brought into question such assertions (Thijssen et al., 2005).

1 2 3 4 5 6 7 8 9 10 Mean SD Meana SDa a

Cu

Fe

Mn

3.2. Metal content Table 3 lists the concentrations of metals (Fe, Mn, Cu, Zn, Na, K, Mg, and Ca) in the muscle of kid goats. The value of Cr was not included in the table because, in all samples analyzed, it was lower than the detection limit (0.2 mg kg1) of the ICP-AES.

Table 3 Metal content (mg kg1) of freeze-dried Garganica kid goat meat. Sample

The SFA percentages found in the present study range from 41.93% to 58.34%. These results appeared within the range of values collected by Banskalieva et al. (2000), but were lower respect to that reported by Banon et al. (2006), who recorded an average value of 69.17%, in perirenal fat, for kid goats reared with similar characteristics. The PUFA/SFA ratio is accepted as a dietetic indicator for meat quality (British Department of Health, 1994). Santos et al. (2007) reported values ranging from 0.09 to 0.12, for intramuscular fat of suckling kids, slaughtered at 8–11 kg of live weight (LW) and similar findings have been reported in this study. Likewise, Banskalieva et al. (2000) suggested that the ratio of (C18 + C18:1)/C16 could be a useful index in describing the potential health effects of different types of lipids. Values reported for this index may range from 2.06, for kids slaughtered at 11 kg LW (Todaro et al., 2004) to 3.39, for kids slaughtered at 5 kg LW (Todaro et al., 2002). For our samples this parameter was on average 2.30, in agreement with the literature. Moreover, to assess the nutritional implications of fat on human diet, the desirable fatty acids (DFA, i.e., MUFA + PUFA + C18:0) were calculated according to Huerta-Leidenz et al. (1991). The average value of 62.76% found in this study, was within the range recorded by Santos et al. (2007).

Zn

Na

K

Mg

Ca

0.82 0.44 0.63 0.65 0.76 0.93 0.31 0.66 0.78 0.56

8.1 5.9 7.2 9.2 4.8 6.9 5.5 8.3 9.4 6.2

0.018 0.003 0.004 0.059 0.024 0.003 0.007 0.042 0.044 0.007

91 82 90 86 96 78 110 123 84 102

3380 2340 2620 2770 3010 2960 2130 2890 2440 3030

17,000 17,900 18,050 17,450 16,800 13,550 15,700 18,350 13,050 17,950

940 960 1030 960 940 780 890 970 800 980

470 340 650 720 610 610 510 420 330 450

0.65 0.18 0.16 0.04

7.2 1.6 1.7 0.4

0.042 0.019 0.010 0.005

94 14 23 3

2760 380 660 90

16,580 1890 3980 450

920 80 220 20

510 130 120 30

Metal content (mg kg1) of goat meat, corrected as reported in the text.

Table 4 d13C and d15N of Garganica kid goat meat. Samples

d13C

d15N

1 2 3 4 5 6 7 8 9 10

26.1 26.7 25.0 23.5 23.7 25.9 25.4 24.5 27.8 26.6

4.2 5.6 6.6 4.5 6.2 5.1 5.4 4.6 4.3 4.8

Mean SD

25.5 1.4

5.1 0.8

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Fig. 1. A typical 1H HR-MAS NMR spectrum of a Garganica kid goat meat.

It should be pointed out again that the results in Table 3 were obtained on ‘‘freeze-dried’’ samples. However, if we consider that the water content in each sample is known (see Table 1), it is possible to recalculate the data on the basis of water loss due to freeze-drying process. The recalculated values of metal concentrations are shown at the bottom of Table 3. 3.3. Isotope ratios The values of d13C and d15N for the ten analyzed samples are reported in Table 4. Generally, stable carbon and nitrogen isotope ratios of animal tissues represent a balance between dietary intake and loss. This assumption is the basis for using animal tissue isotopic compositions (more often nitrogen and carbon) to infer dietary inputs (Schwarcz and Schoeninger, 1991). Isotope fractionation between mothers and offspring is not well-understood. One attractive idea is that offspring are a trophic level higher than their mothers because, through lactation and milk consumption, the offspring ‘‘consume’’ their mothers (Knoff et al., 2008; Newsome et al., 2006). Trophic levels and muscle tissue enrichments can vary from 0.5 to 4.6% for d13C and 1.0–6.0% for d15N (Ambrose and Norr, 1993; De Niro and Epstein, 1978; Hare et al., 1991; Minagawa and Wada, 1984; Schoeninger and De Niro, 1984; Sponheimer et al., 2003a,b). There is a systematic but poorly defined difference between the isotopic composition of the consumer tissues and that of the diet (an enrichment factor, expressed as Dtissue-diet). Unfortunately, no IRMS studies on goat kids reared only with suckling milk are available in the literature, so with the aim to compare the results obtained in this research, similar studies on lamb meat have been considered. In this regard the results concerning d15N and d13C isotopic ratios were not significantly different from values showed for lamb meat types reported in a previous study (Sacco et al., 2005). In addition, Camin et al. (2007) have proved the usefulness of multi-element (H, C, N, and S) stable isotope ratio analysis for geographical provenance assignment of lamb meat from several European regions. In this study it is showed that when lambs were fed milk (e.g., lambs from Toscana), relatively elevated d13C values were observed. This is due to the fact that each step in the food chain (or trophic level) leads to an

enrichment of heavy isotopes (De Niro and Epstein, 1978; Steele and Daniel, 1978). 3.4. NMR spectra 1 H HR-MAS NMR spectrum of a Garganica kid goat meat sample is shown in Fig. 1. The most intense signals are due to fatty acids of triacylglicerides and carnosine, although also signals due to other metabolites (amino acids, organic acids and sugars) have remarkable intensities. The fact that signals due to fatty acids, insoluble in D2O (the solvent used), are visible in the spectrum together with soluble molecules indicates an important advantage of 1H HR-MAS spectroscopy: it permits analysis of different classes of compounds in a single experiment. In all the performed meat spectra the same signals were present but with different intensities. Complete signal assignments have already been reported for beef meat (Brescia et al., 2002b).

4. Conclusions In the present work, conventional analyses (moisture, ashes, fat and protein content), major and trace metal determinations and innovative analyses (stable isotope ratios, 1H HR-MAS NMR) were used in synergy to give a detailed description of the physico-chemical composition of the Garganica kid goat meat. The results presented herein are in accordance with the works reported by other authors on analog meat products, although a punctual comparison could not be made because different breeds and/or other anatomical sections have been considered. In particular, it should be highlighted that in this work a high protein content (18.9%), a low level of fat (2.98%), good values of (C18 + C18:1)/C16 ratios, as well as a considerable desirable fatty acid content (62.76%) were found. These results indicate that Garganica kid goat meat may be recommended as a valuable component for health conscious consumer’s diet, since the above reported parameters are related to a high nutritional value and are known to be important indexes of beneficial effects on human health. The specific location of the goat farms under study in the Gargano environment, and the traditional type of livestock-rearing practiced, can be considered

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responsible for the peculiar chemico-physical composition of Garganica kid goat meat and for its potential on human diet and health. Acknowledgement This work was completely supported by the Gargano Mountain Community (Contract No. 607). References Al-Jowder, O., Casuscelli, F., Defernez, M., Kemsley, E.K., Wilson, R.H., Colquhoun, I.J., 2001. High resolution NMR studies of meat composition and authenticity. In: Webb, G.A., Belton, P.S., Gil, A.M., Delgadillo, I. (Eds.), Magnetic Resonance in Food Science: a View to the Future. Royal Society of Chemistry, Cambridge, UK, pp. 232–238. Ambrose, S.H., Norr, L., 1993. Experimental evidence for the relationship of the carbon isotope ratios of whole diet and dietary protein to those of bone collagen and carbonate. In: Lambert, J.B., Grupe, G. (Eds.), Prehistoric Human Bone: Archaeology at the Molecular Level. Springer-Verlag, Berlin, Germany, pp. 1–37. Atti, N., Mahouachi, M., Rouissi, H., 2006. The effect of spineless cactus (Opuntia ficusindica f. inermis) supplementation on growth, carcass, meat quality and fatty acid composition of male goat kids. Meat Science 73, 229–235. Banon, S., Vila, R., Price, A., Ferrandini, E., Garrido, M.D., 2006. Effects of goat milk or milk replacer diet on meat quality and fat composition of suckling goat kids. Meat Science 72, 216–221. Banovic, M., Grunert, K.G., Barreira, M.M., Fontes, M.A., 2009. Beef quality perception at the point of purchase: a study from Portugal. Food Quality and Preference 20, 335–342. Banovic, M., Grunert, K.G., Barreira, M.M., Fontes, M.A., 2010. Consumers’ quality perception of national branded, national store branded, and imported store branded beef. Meat Science 84, 54–65. Banskalieva, V., Sahlu, T., Goetsch, A.L., 2000. Fatty acid composition of goat muscles and fat depots: a review. Small Ruminant Research 37, 255–268. Bas, P., Dahbi, E., El Aich, A., Morand-Fehr, P., Araba, A., 2005. Effect of feeding on fatty acid composition of muscles and adipose tissues in young goat raised on the argan tree forest of Morocco. Meat Science 71, 317–326. Belton, P.S., Colquhoun, I.J., Kemsley, E.K., Delgadillo, I., Roma, P., Dennis, M.J., Sharman, M., Holmes, E., Nicholson, J.K., Spraul, M., 1998. Application of chemometrics to the 1H-NMR spectra of apple juices: discrimination between apple varieties. Food Chemistry 61, 207–213. Bernue´s, A., Olaizola, A., Corcoran, K., 2003. Labelling information demanded by European consumers and relationships with purchasing motives, quality and safety of meat. Meat Science 65, 1095–1106. Beserra, F.J., Madruga, M.S., Leite, A.M., Da Silva, E.M.C., Maia, E.L., 2004. Effect of age at slaughter on chemical composition of meat from Moxoto´ goats and their crosses. Small Ruminant Research 55, 177–181. Bonny, J.M., Laurent, W., Labas, R., Taylor, R., Berge, P., Renou, J.P., 2001. Magnetic resonance imaging of connective tissue: a non-destructive method for characterising muscle structure. Journal of the Science of Food and Agriculture 81 (3), 337–341. Bredahl, L., 2003. Cue utilisation and quality perception with regard to branded beef. Food Quality and Preference 15, 65–75. Brescia, M.A., Caldarola, V., De Giglio, A., Benedetti, D., Fanizzi, F.P., Sacco, A., 2002a. Characterization of the geographical origin of Italian red wines based on traditional and nuclear magnetic resonance spectrometric determinations. Analytica Chimica Acta 458, 177–186. Brescia, M.A., Caputi Jambrenghi, A., Di Martino, V., Sacco, D., Giannico, F., Vonghia, G., Sacco, A., 2002b. High resolution nuclear magnetic resonance spectroscopy (NMR) studies on meat components: potentialities and prospects. Italian Journal of Animal Science 1 (2), 151–158. British Department of Health, 1994. Nutritional Aspects of Cardiovascular Disease, Report on Health and Social Subjects, vol. 46. HMSO, London. Brzostowski, H., Niz˙nikowski, R., Tan´ski, Z., 2008. Quality of goat meat from purebred French Alpine kids and Boer crossbreeds. Archiv fur Tierzucht – Archives of Animal Breeding 51, 381–388. Camin, F., Bontempo, L., Heinrich, K., Horacek, M., Kelly, S.D., Schlicht, C., Thomas, F., Monahan, F.J., Hoogewerff, J., Rossmann, A., 2007. Multi-element (H, C, N, S) stable isotope characteristics of lamb meat from different European regions. Analytical and Bioanalytical Chemistry 389, 309–320. Costa, P., Roseiro, L.C., Bessa, R.J.B., Padilha, M., Partidario, A., Marques de Almeida, J., Calkins, C.R., Santos, C., 2008. Muscle fiber and fatty acid profiles of MertolengaPDO meat. Meat Science 78, 502–512. De Niro, M.J., Epstein, S., 1978. Influence of diet on the distribution of carbon isotopes in animals. Geochimica et Cosmochimica Acta 42, 495–506. Dhanda, J.S., Taylor, D.G., Murray, P.J., 2003. Carcass composition and fatty acid profiles of adipose tissue of male goats: effects of genotype and live weight at slaughter. Small Ruminant Research 50, 67–74. Foucat, L., Taylor, R.G., Labas, R., Renou, J.P., 2001. Characterization of frozen fish by NMR imaging and histology. American Laboratory 33 (8), 38–43. Grundy, S.M., Denke, M.A., 1990. Dietary influences on serum lipids. Journal of Lipid Research 31, 1149–1172.

Hare, P.E., Fogel, M.L., Stafford, T.W., Mitchell, A.D., Hoering, T.C., 1991. The isotopic composition of carbon and nitrogen in individual amino acids isolated from modern and fossil proteins. Journal of Archaeological Science 18, 277–292. Heaton, K., Kelly, S., Hoogewerff, J., 2003. The geographical origin of beef: possibilities for traceability schemes based on light and heavy stable isotope analysis. In: Proceedings 7th International Symposium on Food Authenticity and Safety, 15–17 October 2003, Nantes, France. Horcada, A., Ripoll, G., Alcalde, M.J., Sanudo, C., Teixeira, A., Panea, B., 2012. Fatty acid profile of three adipose depots in seven Spanish breeds of suckling kids. Meat Science, http://dx.doi.org/10.1016/j.meatsci.2012.04.018. Huerta-Leidenz, N.O., Cross, H.R., Lunt, D.K., Pelton, L.S., Savell, J.W., Smith, S.B., 1991. Growth, carcass traits, and fatty acid profiles of adipose tissues from steers fed whole cottonseed. Journal of Animal Science 69, 3665–3672. INRAN, Istituto Nazionale di Ricerca per gli Alimenti e la Nutrizione, 2009. Tabelle di composizione degli alimenti. INRAN, Italy. Kemsley, E.K., Holland, J.K., Defernez, M., Wilson, R.H., 1996. Detection of adulteration of raspberry purees using infrared spectroscopy and chemometrics. Journal of Agricultural and Food Chemistry 44, 3864–3870. Knoff, A., Hohm, A., Macko, S., 2008. Ontogenetic diet changes in bottlenose dolphins (Tursiops truncacatus) reflected through stable isotopes. Marine Mammal Science 24, 128–137. Mahgoub, O., Khan, A.J., Al-Maqbaly, R.S., Al-Sabahi, J.N., Annamalai, K., Al-Sakry, N.M., 2002. Fatty acid composition of muscle and fat tissues of Omani Jebel Akhdar goats of different sexes and weights. Meat Science 61, 381–387. Maltin, C., Balcerzak, D., Tilley, R., Delday, M., 2003. Determinants of meat quality: tenderness. Proceedings of the Nutrition Society 62, 337–347. Manca, G., Camin, F., Coloru, G.C., Del Caro, A., Depentori, D., Franco, M.A., Versini, G., 2001. Characterization of the geographical origin of Pecorino Sardo cheese by casein stable isotope (13C/12C and 15N/14N) ratios and free amino acid ratios. Journal of Agricultural and Food Chemistry 49 (3), 1404–1409. Minagawa, M., Wada, E., 1984. Stepwise enrichment of 15N along foodchains – further evidence and the relation between delta-n-15 and animal age. Geochimica et Cosmochimica Acta 48, 1135–1140. Newsome, S.D., Koch, P.L., Etnier, M.A., Aurioles-Gamboa, D., 2006. Using carbon and nitrogen to investigate maternal strategies in Northeast Pacific Otariids. Marine Mammal Science 22, 556–572. Offer, G., Knight, P., 1988. The structural basis of water-holding in meat. Part 2: drip losses. In: Lawrie, R. (Ed.), Developments in Meat Science, vol. 4. Elsevier Applied Science, London, UK, pp. 173–243. Osorio, M., Zumalaca´rregui, T., Figueira, J.M., Mateo, A.J., 2007. Fatty acid composition in subcutaneous, intermuscular and intramuscular fat deposits of suckling lamb meat: effect of milk source. Small Ruminant Research 73, 127–134. Piasentier, E., Valusso, R., Camin, F., Versini, G., 2003. Stable isotope ratio analysis for authentication of lamb meat. Meat Science 64, 239–247. Renou, J.-P., Bielicki, G., Deponge, C., Gachon, P., Micol, D., Ritz, P., 2004. Characterization of animal products according to geographic origin and feeding diet using nuclear magnetic resonance and isotope ratio mass spectrometry. Part II: beef meat. Food Chemistry 86, 251–256. Rhee, K.S., Waldron, D.F., Ziprin, Y.A., Rhee, K.C., 2000. Fatty acid composition of goat diets vs. intramuscular fat. Meat Science 54, 313–318. Rossmann, A., Haberhauer, G., Ho¨lzl, S., Horn, P., Pichlmayer, F., Voerkelius, S., 2000. The potential of multielement stable isotope analysis for regional origin assignment of butter. European Food Research and Technology 211, 32–40. Sacco, D., Brescia, M.A., Buccolieri, A., Caputi Jambrenghi, A., 2005. Geographical origin and breed discrimination of apulian lamb meat samples by means of analytical and spectroscopic determinations. Meat Science 71, 542–548. Santos, V.A.C., Silva, A.O., Cardoso, J.V.F., Silvestre, A.J.D., Silva, S.R., Martins, C., Azevedo, J.M.T., 2007. Genotype and sex effects on carcass and meat quality of suckling kids protected by the PGI ‘‘Cabrito de Barroso’’. Meat Science 75, 725–736. Sanz-Sampelayo, M.R., Chilliard, Y., Schmidely, Ph., Boza, J., 2007. Influence of type of diet on the fat constituents of goat and sheep milk. Small Ruminant Research 68, 42–63. Schoeninger, M.J., De Niro, M.J., 1984. Nitrogen and carbon isotopic composition of bone collagen from marine and terrestrial animals. Geochimica et Cosmochimica Acta 48, 625–639. Schwarcz, H.P., Schoeninger, M.J., 1991. Stable isotope analyses in human nutritional ecology. Yearbook of Physical Anthropology 34, 283–321. Sponheimer, M., Robinson, T., Ayliffe, L., Roeder, B., Hammer, J., Passey, B., West, A., Cerling, T., Dearing, D., Ehleringer, J., 2003a. Nitrogen isotopes in mammalian herbivores: hair d15N values from a controlled feeding study. International Journal of Osteoarchaeology 13, 80–87. Sponheimer, M., Robinson, T., Ayliffe, L., Passey, B., Roeder, B., Shipley, L., Lopez, E., Cerling, T., Dearing, D., Ehleringer, J., 2003b. An experimental study of carbon isotope fractionation between diet, hair, and feces of mammalian herbivores. Canadian Journal of Zoology 81, 871–876. Steele, K.W., Daniel, R.M., 1978. Fractionation of nitrogen isotopes by animals: a further complication to the use of variations in the natural abundance of 15N for tracer studies. The Journal of Agricultural Science 90, 7–9. Thijssen, M., Hornstra, G., Mensink, R.P., 2005. Stearic, oleic, and linoleic acids have comparable effects on markers of thrombotic tendency in healthy human subjects. The Journal of Nutrition 135, 2805–2811. Todaro, M., Corrao, A., Barone, C.M.A., Schinelli, R., Occidente, M., Giaccone, P., 2002. The influence of age at slaughter and litter size on some quality traits of kid meat. Small Ruminant Research 44, 75–80.

F. Longobardi et al. / Journal of Food Composition and Analysis 28 (2012) 107–113 Todaro, M., Corrao, A., Alicara, M.L., Schinelli, R., Giaccone, P., Priolo, A., 2004. Effects of litter size and sex on meat quality traits of kid meat. Small Ruminant Research 54, 191–196. Tshabalala, P.A., Strydom, P.E., Webb, E.C., De Kock, H.L., 2003. Meat quality of designated South African indigenous goat and sheep breeds. Meat Science 65, 563–570. Ulbricht, T.L.V., Southgate, D.A.T., 1991. Coronary heart disease: seven dietary factors. The Lancet 338, 985–992. Vogels, J.T.W., Terwel, L., Tas, A.C., van der Berg, F., Dukel, F., van der Greef, J., 1996. Detection of adulteration in orange juices by a new screening method using proton NMR spectroscopy in combination with pattern

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recognition techniques. Journal of Agricultural and Food Chemistry 44, 175–180. Webb, E.C., Casey, N.H., Simela, L., 2005. Goat meat quality. Small Ruminant Research 60, 153–166. Werdi Pratiwi, P.J., Murray, Taylor, D.G., 2007. Feral goats in Australia: a study on the quality and nutritive value of their meat. Meat Science 75, 168–177. Williams, C.M., 2000. Dietary fatty acids and human health. Anales de Zootechnie 49, 165–180. Zamora, R., Go´mez, G., Hidalgo, F.J., 2002. Classification of vegetable oils by highresolution 13C-NMR spectroscopy using chromatographically obtained oil fractions. Journal of the American Oil Chemists Society 79, 267–272.