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1.
Background and Aims: δ13C values from Vitis vinifera leaves, whole grape, seed, pulp, skin and/or grape must sugars have been investigated as an integrated marker of vine water status or intrinsic water-use efficiency during berry growth and across region of origin, vintage and variety. The use of 18O/16O isotopic ratio as a marker of water addition, vintage and geographical origin has also been studied. This paper examines the effect of irrigation and grapevine variety on δ18O and δ13C of grape must from eight varieties, all cultivated in the same vineyard to reduce the effects from other variables. Methods and Results: Stable isotope compositions of grape must water and sugar were determined by isotope ratio mass spectrometry. The result of the study showed statistically significant effects of irrigation and vine variety on both δ18O and δ13C. The effect of vintage on δ18O was only significant for non-irrigated vines. Conclusion: This research highlights the effect of variety and irrigation on δ13C and δ18O of grape. Significance of the Study: This is the first report to demonstrate that the varietal effect on δ13C and δ18O of grape is not due only to differences in the vegetative cycle of each variety. It further suggests that water exhibits a lower isotopic discrimination in the indigenous Spanish varieties studied than in non-indigenous varieties.  相似文献   

2.
Beef samples originating from the major cattle producing regions of the world (Europe, USA, South America, Australia and New Zealand) have been analysed using IRMS and ICP-MS. C and N isotope composition of the beef defatted dry mass and H and O isotope composition of the corresponding lipid fractions were determined. It was observed that intensive maize and/or C4 pasture feeding, during cattle production, gave rise to significant differences in the 13C content of beef produced in Brazil and the USA versus British beef fed predominantly on C3 pasture and fodder. The mean δ2H‰ and δ18O‰ values of beef lipid correlated well with the latitude of production regions and the relationship between the H and O isotopic contents were found to parallel the Meteoric Water Line. These findings support the hypothesis that the systematic global variations in the 2H and 18O content of precipitation are transferred through drinking water and feed into beef lipid. Multi-element concentrations determined in the beef were combined with the stable isotope data and submitted to multivariate analysis. Six key variables (δ13C‰ (defatted dry mass), Sr, Fe, δ2H‰ (lipid), Rb and Se) were identified by canonical discriminant analysis as providing the maximum discrimination between beef samples on the basis of the broad geographical areas (Europe, South America and Australasia). It was concluded that the methodology in its current state can be used to provide reliable origin information, but this is dependent upon the countries under investigation.  相似文献   

3.
Within the EU-project “Pure Juice” established stable isotope methods (δ2H, δ13C, δ15N) have been applied and improved in order to determine and verify the geographical origin of orange juices. In addition, new approaches employing analyses of δ34S and 87Sr/86Sr have been developed and tested. Approximately 150 authentic orange juice samples from several regions in North- and South-America, Africa and Europe have been analysed. A discrimination of orange producing regions, based on the results which ultimately depend on geographical, climatic and lithological differences was successfully performed. Furthermore, we demonstrate that blending of single strength juice by adding concentrate can be revealed by comparing 87Sr/86Sr of soluble and insoluble components of the juices. We conclude that regional assignment of orange juice samples is most successful when single parameters are combined in a “multi-element approach”.  相似文献   

4.
“Oloroso” sherry wines, belonging to the denominations of origin Jerez-Xérès-Sherry (JX), Montilla-Moriles (MM) and Condado de Huelva (CH) (Andalusia, Spain), were analysed for their contents of Ca, Mg, Fe, Cu, Mn and Zn by flame atomic absorption spectrophotometry, and Na, K, Al and Sr by flame atomic emission spectrophotometry. Among the three denominations of origin, differences in the mean contents were found for Na, Mg, Fe, Al and Sr. Cluster analysis showed that these differences were significant. Linear discrimination analysis, using Na, Mg, Fe, Al and Sr, gave 100% recognition ability and 93% prediction ability.  相似文献   

5.
The effects of wheat and bean straw growing substrates on nutrient contents of three edible oyster mushrooms and sensory properties of two mushroom foods were investigated. Moisture (fresh weight basis), crude protein, fat, fibre, ash, total carbohydrate, Fe, P and Zn (db) were ranged: 85.18–88.86%, 30.04–37.63%, 1.61–2.55%, 9.33–13.29%, 6.83–9.38%, 29.68–32.53%, 4.86–5.66 mg per 100 g, 12.39–15.36 g kg?1 and 54.61–65.98 mg kg?1, respectively. Moisture, fat and fibre were significantly (P < 0.01) affected by substrates, species and their interactions. Substrates showed no differences on ash, Fe and P (P > 0.05). Protein content was high for mushrooms grown on bean straw. Pleurotus sajor‐caju grown on bean straw had high protein, ash, Fe and P contents. No significant (P > 0.05) sensory acceptability differences were observed for boiled mushroom and mushroom sauce except colour of boiled mushrooms. In Ethiopia, if mushroom consumption is popularised, the support for food nutrition security is substantial.  相似文献   

6.
The aim of this study was to examine the minerals content (toxic elements, macro-elements and trace elements) of Basilicata region (southern Italy) honeys and compare the mineral profile of honeys classified as rural, industrial and urban according to anthropic characteristics of geographical origin. Overall, Ca, Na, Mg, Fe, Al, Zn and Mn were the most abundant elements detected in honeys, with average contents exceeding 1 ppm, whereas heavy metals content was lower than the maximum limit established for honey. Statistical analysis revealed significant differences (P < 0.05) among honeys as function of anthropic characteristics of geographical origin, with the exception for Se, Co and Ag content. Industrial honeys were characterised by the highest Zn, Cr, Sn, Cd and Pb content, urban honeys showed the highest As, Fe, Ni, Mn, Na, Mg and Ca content, whereas rural honeys showed the highest Cu, Al and Ba content (P < 0.05). The findings of this study highlighted that honeys mineral profile is closely related to different content of elements in environment, which is affected by anthropogenic activities.  相似文献   

7.
We determined carbon and nitrogen contents (C and N contents) and stable carbon, nitrogen, and oxygen isotopic compositions (δ13C, δ15N, and δ18O) of polished rice in order to develop a simple method to discriminate its geographical origin. As a first attempt, we examined a single cultivar, Koshihikari rice, from 14 different cultivation areas including Australia (n = 1), Japan (n = 12), and USA (n = 1). For all rice samples, C and N contents and the isotopic compositions are consistent with those of general plant materials, being 37.2–40.0% (C content), 0.8–1.4% (N content), −27.1 to −25.4% (δ13C), +0.4 to +9.0% (δ15N), and +18.8 to +22.9% (δ18O). However, its cultivated area is clearly distinguished by a pentagonal radar plot based on the elemental and isotopic compositions. Thus, the comparison of C and N contents and δ13C, δ15N, and δ18O values would potentially be useful for rapid and routine discrimination of geographical origin of the polished rice.  相似文献   

8.
The aim of this study was to examine the variation in carbon and nitrogen stable isotope ratios in cattle tissues from different provinces in China, and to investigate the correlations of δ13C and δ15N values between different cattle tissues. Furthermore, the success rate of classification using δ13C and δ15N values to distinguish the geographical origin of cattle was analyzed. Fifty nine cattle samples were collected from Jilin, Ningxia, Guizhou and Hebei provinces in China, and the δ13C and δ15N values of de-fatted beef, crude fat and tail hair were measured using isotope ratio mass spectrometry (IRMS). There were highly significant regional differences in the mean values of δ13C and δ15N values in the cattle tissues. A significant correlation was found in δ13C and δ15N between de-fatted beef, crude fat and tail hair, which indicated that all of these matrices could be used to trace cattle to their geographical origin. The results of discriminant analysis showed that δ13C was the better indicator for cattle origin traceability than δ15N. The classification success rate could be improved greatly by combining the two indicators. It was concluded that stable isotope analysis of C and N in cattle tissue can be used to trace cattle diet and origin in China.  相似文献   

9.
Packaging fresh lamb in a vacuum (VAC) versus a 100% CO2 modified atmosphere (MAP) may influence product shelf-life and the bacterial communities. While VAC is a common packing method and 100% CO2 MAP is used in some countries, there is little information about how these different techniques affect the growth of spoilage bacteria and sensory attributes of lamb. The aim of this study was to assess changes in microbiological and organoleptic properties, and determine differences in microbial communities by terminal restriction fragment length polymorphism (TRFLP) and 454 pyrosequencing, in bone-in (BI) and bone-out (BO) MAP- and VAC-packed lamb shoulders stored at −0.3 °C over 12 wk. VAC and MAP lamb shoulders were acceptable in sensory test scores over 12 wk of storage at −0.3 °C, despite total viable count (TVC) and lactic acid bacteria (LAB) levels increasing to 8 log10 CFU/cm2 for VAC lamb and 4–6 log10 CFU/cm2 for MAP lamb. Similar to the sensory results, there were no significant differences in microbial communities between BI and BO product. However, types of bacteria were different between VAC and MAP packaging. Specifically, while VAC shoulder became dominated by Carnobacterium spp. in the middle of the storage period, the MAP shoulder microbial population remained similar from the start until later storage times.  相似文献   

10.
In this review, we examine the variation in stable isotope signatures of the lighter elements (δ2H, δ13C, δ15N, δ18O, and δ34S) of tissues and excreta of domesticated animals, the factors affecting the isotopic composition of animal tissues, and whether stable isotopes may be used to differentiate organic and conventional modes of animal husbandry. The main factors affecting the δ13C signatures of livestock are the C3/C4 composition of the diet, the relative digestibility of the diet components, metabolic turnover, tissue and compound specificity, growth rate, and animal age. δ15N signatures of sheep and cattle products have been related mainly to diet signatures, which are quite variable among farms and between years. Although few data exist, a minor influence in δ15N signatures of animal products was attributed to N losses at the farm level, whereas stocking rate showed divergent findings. Correlations between mode of production and δ2H and δ18O have not been established, and only in one case of an animal product was δ34S a satisfactory marker for mode of production. While many data exist on diet–tissue isotopic discrimination values among domesticated animals, there is a paucity of data that allow a direct and statistically verifiable comparison of the differences in the isotopic signatures of organically and conventionally grown animal products. The few comparisons are confined to beef, milk, and egg yolk, with no data for swine or lamb products. δ13C appears to be the most promising isotopic marker to differentiate organic and conventional production systems when maize (C4) is present in the conventional animal diet. However, δ13C may be unsuitable under tropical conditions, where C4 grasses are abundant, and where grass-based husbandry is predominant in both conventional and organic systems. Presently, there is no universal analytical method that can be applied to differentiate organic and conventional animal products.  相似文献   

11.
The purpose of this study was to prepare a defatted peanut flour‐based film (DPFF); to characterise their physicochemical, optical, barrier and mechanical properties; and to evaluate the defatted peanut flour package efficacy to preserve the chemical quality of sunflower oil during storage. The film presented high lightness values (L* = 86.83). The water vapour permeability was 5.44 × 10?11 g m?1 s?1 Pa?1. Tensile strength and percentage of elongation were 1.01 MPa and 84.01%, respectively. Sunflower oil samples packaged in defatted peanut flour packages (DPFP) were stored during 67 days at room temperature. Peroxide value and conjugated dienes increased less for sunflower oil conditioned in DPFP and high barrier plastic pouches (EVOH) during storage than sunflower oil conditioned in Petri dishes (C). The use of DPFP improved the chemical stability of sunflower oil during storage. The DPFF showed suitable film properties, and also, the capacity to be incorporated in food packaging applications.  相似文献   

12.
The potential for using visible spectroscopy (400–700 nm) to classify six types (breed × production system) of lamb meat was investigated. Seven wavelengths namely 400, 410, 420, 450, 510, 610 and 670 nm were retained for the discriminant analysis. The basic meat physicochemical traits of Longissimus dorsi were also studied and a model including that information together with the spectra was developed to compare both accuracies. Then, Myoglobin content, water holding capacity, pH, a*, 670 and 610 nm wavelengths, protein percentage, L*, ash content, 450 and 420 nm wavelengths and moisture percentage were selected as variables for the development of the discriminant function. The data analysis showed that it was possible to discriminate the lamb types with accuracy around 83% using visible spectroscopy. However these results improved to 95% when using the reflectance together with basic physicochemical traits (12% better than using only the spectra).  相似文献   

13.
Coconut water is a natural isotonic, nutritive, and low-caloric drink. Preservation process is necessary to increase its shelf life outside the fruit and to improve commercialization. However, the influence of the conservation processes, antioxidant addition, maturation time, and soil where coconut is cultivated on the chemical composition of coconut water has had few arguments and studies. For these reasons, an evaluation of coconut waters (unprocessed and processed) was carried out using Ca, Cu, Fe, K, Mg, Mn, Na, Zn, chloride, sulfate, phosphate, malate, and ascorbate concentrations and chemometric tools. The quantitative determinations were performed by electrothermal atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and capillary electrophoresis. The results showed that Ca, K, and Zn concentrations did not present significant alterations between the samples. The ranges of Cu, Fe, Mg, Mn, PO43−, and SO42− concentrations were as follows: Cu (3.1–120 μg L−1), Fe (60–330 μg L−1), Mg (48–123 mg L−1), Mn (0.4–4.0 mg L−1), PO43− (55–212 mg L−1), and SO42− (19–136 mg L−1). The principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to differentiate unprocessed and processed samples. Multivariated analysis (PCA and HCA) were compared through one-way analysis of variance with Tukey–Kramer multiple comparisons test, and p values less than 0.05 were considered to be significant.  相似文献   

14.
The determination of 18 elements (V, Cr, Cu, Co, Se, Sr, Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn, Fe, Mg and Zn) in leaves, flowers and the infusion from Salvia fruticosa, a sage grown in Greece, is described. For this purpose, flame atomic absorption spectrometry has been used for the determination of Fe, Mg, Zn and inductively coupled plasma-mass spectrometry has been used for the determination of V, Cr, Cu, Co, Se, Sr, Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn using 45Sc 72Ge, 115In and 232Th as internal standards. The elemental content was found to be in the range of 0.01 (Bi)-30.8 (Mn) mg/Kg (leaves), 0.30 (Bi)-39.1 (Mn) mg/Kg (flowers), 0.003 (Sb)-20.4 (Mn) mg/Kg (infusion) for V, Cr, Cu, Co, Se, Sr, Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn and in the range of 0.07 (Zn)-3.21 (Mg) g/kg (leaves) for Fe, Mg and Zn. The majority of the samples were collected from six sites in the island Crete and transplanted and grown in a model farm. Chemometric techniques were used to investigate the original site classification according to their elemental content, and it was proved that the initial cultivation sites were characterized by only five elements (Sb, V, Zn, Cd and Cr). The application of factor analysis revealed significant correlation between certain elements, denoting their common sources. In addition, the total antioxidant activity of the herbal preparation was determined by measuring the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity. Microwave-assisted extraction (MAE) was used to extract total antioxidants and the effect of temperature, time and solvent in the extraction efficiency was investigated. The determination of the antioxidant activity was based on the % inhibition of the absorbance signal of the radical DPPH at 515 nm, after the addition of herbal’s extract. The IC50 values were found to be in the range of 10.6–40.1 mg/L.  相似文献   

15.
Extension of the display life of lamb with an antioxidant active packaging   总被引:5,自引:2,他引:5  
Camo J  Beltrán JA  Roncalés P 《Meat science》2008,80(4):1086-1091
Fresh lamb steaks were treated with three different preparations of natural antioxidants: one group was packaged with a rosemary active film, the second group was packaged with an oregano active film, and the third group was sprayed on the meat surface with a rosemary extract before packaging in a high-oxygen atmosphere. Samples were stored under illumination at 1 ± 1 °C for 13 days. Metmyoglobin formation, lipid oxidation (TBARS), instrumental colour (CIE a*), psychrotrophic bacterial counts (PCA), sensory discolouration and off-odour were determined. The use of a rosemary extract, a rosemary active film or an oregano active film resulted in enhanced oxidative stability of lamb steaks. Active films with oregano were significantly more efficient than those with rosemary, exerting an effect similar to that of direct addition of the rosemary extract; in fact, they extended fresh odour and colour from 8 to 13 days compared to the control.  相似文献   

16.
Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system. The production GABA from the cheaper glutamic acid is a valuable process. Rice bran is a potential source of glutamic acid decarboxylase which was therefore selected for production of gamma-aminobutyric acid (GABA) using lactic acid bacteria (Lactobacillus brevis (Lb.brevis) VTCC-B397). The influences of treatment of defatted rice bran with α-amylase, Alcalase (Al), Flavourzyme (Fl) and their combinations at different concentration ratios on the GABA synthesis were examined. With α-amylase impacts, concentration of GABA (6.41 mg mL−1) was about 2.38 times higher than the control sample (2.69 mg mL−1) under hydrolysis conditions of pH 6.5, temperature of 95 °C and α-amylase concentration of 0.15% (v/w) for 45 min. The α-amylase hydrolysis as prerequisite for protein hydrolysis using Al: Fl (ratio Al: Fl of 3: 7, concentration of 2% (w/w), pH = 8, temperature of 50 °C) reached the highest GABA synthesis efficiency, at 8.43 mg mL−1. Results showed that the enzyme treatment positively affected the fermentation using Lb. brevis for GABA biosynthesis from defatted rice bran.  相似文献   

17.
《Food chemistry》2005,91(4):593-600
Trace and minor elements in Slovenian honey were analysed by total reflection X-ray fluorescence spectroscopy. Upto 16 elements (K, Cl, S, P, Ca, Mn, Rb, Cu, Fe, Ni, Cr, Br, Ti, Pb, Sr and As) were detected, in a range of average content from 1.24 mg kg−1 for Sr to 2590 mg kg−1 for K. Statistically significant differences were established between different types of honey (acacia, floral, lime, chestnut, spruce, fir, forest and Metcalfa pruinosa honeydew honey). The highest content of elements was determined in forest honey and the lowest in acacia honey. Honeys were also separated according to their botanical origin as nectar honey or honeydew honey. Total elemental content and the content of S, Cl, K and Rb in honeydew honey was statistically significantly higher than in nectar honey. Chestnut honey differed in statistically its significantly higher contents of Rb and Ca from nectar and honeydew honeys. The year of honey production proved to have no statistically significant influence on elemental content. A comparison of our data with the literature data showed a relatively large diversity.  相似文献   

18.
In a preliminary study with commercial ewe's milk cheeses, there were statistically significant differences in the sensory evaluation scores and the amounts of short-chain (C4–C10) free fatty acids (FFAs) between cheeses made with lamb rennet paste or bovine rennet. Experimental ewe's milk cheeses were manufactured with 2 levels of artisanally produced lamb rennet paste and 2 levels of bovine rennet in 50 L vats, with a manufacturing replicate done within 1 week. Total coagulating activity was 2500 RU for cheeses manufactured with a high amount of rennet or 1000 RU for cheeses manufactured with a low amount of rennet. The two batches of lamb rennet pastes used had 4.0 (early Spring) and 6.5 U g−1 lipase (late Spring), whereas no lipase activity was detected in bovine rennets. The total concentration of FFAs in cheeses manufactured with lamb rennet paste was significantly higher than in cheeses manufactured with bovine rennet, regardless of ripening time and time of the year. Lipolysis in the former cheeses increased with the total units of lipolytic activity added. The increase in lipolysis in cheeses made with lamb rennet was primarily due to higher amounts of short-chain fatty acids (C4–C10). Butyric acid was the main FFA in cheeses made with lamb rennet paste, representing 34.5 μmol 100 μmol−1 (low level of rennet) and 44.2 μmol 100 μmol−1 (high level of rennet) of the total FFAs, whereas it represented only 17 μmol 100 μmol−1 of the total FFAs in all cheeses made with bovine rennet. The concentration of individual FFAs of chain length <C12 were significantly higher in cheeses made with lamb rennet paste than in cheeses made with bovine rennet. Cheeses made with lamb rennet paste received significantly higher intensity scores for odour and flavour intensity, sharp odour, ‘piquant’ and bitter flavours and ‘natural rennet’ odour and flavour.  相似文献   

19.
Soybeans grown hydroponically labeled with 59Fe or two levels of a 51Cr-65Zn mixture were analyzed for the distribution of these radionuclides in mature edible and nonedible parts. The concentration of 59Fe was significantly higher in the hulls than in other plant parts unlike for 51Cr and 65Zn. The seeds produced were then processed into a defatted soybean meal in order to investigate the effects of processing on the content of iron, zinc, and chromium. No detectable change in total Zn content and no significant change in 51Cr content were evident during processing. However, an overall 9% gain of total Fe content was observed as a result of processing probably due to Fe contamination by processing equipment.  相似文献   

20.
Tiezheng Ma  Haiwen Wu 《LWT》2010,43(9):1450-1398
By ethanol precipitation and physical separation procedures, the peanut protein concentrate (PPC) was isolated from defatted peanut flour (DPF) and the extraction times were determined as twice. The effects of liquid-to-solid ratio, ethanol concentration and reaction temperature on the solubility of PPC were studied for the primary extraction and the later two factors were studied for the second extraction by response surface methodology (RSM). The results showed that for both of the second-order models, the coefficient determination (R2) was good and a liquid-to-solid ratio of 11.79: 1 (v/w), an ethanol concentration of 85 mL/100 mL, an extract temperature of 36.35 °C for the primary extraction and a corresponding list of variables of 8:1 (v/w), 97.50 mL/100 mL and 38.40 °C for the secondary extraction were found to be optimal for the protein extraction from defatted peanut flour. By means of additional experiments, the adequacy of the model was confirmed.  相似文献   

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