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1.
B. Roth    D. Moeller    J.O. Veland    A. Imsland    E. Slinde 《Journal of food science》2002,67(4):1462-1466
Shear force and rigor mortis were used to evaluate the post‐mortem changes of muscle texture in Atlantic salmon (Salmo salar). The fish were either stunned with carbon dioxide (CO2), electricity, or percussion prior to slaughter. The pre‐mortem stress during CO2 stunning resulted in an earlier onset and resolution of rigor mortis, and accelerated post‐mortem softening of the muscle tissue as compared to the other stunning methods. No significant differences, either in development of rigor mortis or shear force, were seen between fish that were stunned with electricity or by percussion. Consequently electricity can be used for stunning fish prior to slaughter.  相似文献   

2.
Several techniques were used, mainly mass spectrometry connected with gas chromatography, matrix-assisted laser desorption with ionization time-of-flight and mass spectrometry connected with liquid chromatography. A major problem was encountered in determining glutathione, which can be conditioned by the pH and selected reducing agents. The GSH form can be oxidized through derivatization, and a small glutathione amount in the biological samples may hinder the determination process. Another problem is the existence of a metal ion in the tested organism; therefore, often a reagent with a chelating function is added to the sample and the mobile phase in liquid chromatography is applied with appropriate polarity for GSH and GSSG. We determined the concentrations of total, reduced, and oxidized glutathione in the liver, hepatopancreas, muscle, and gonad tissues of brown shrimp (Crangon crangon) and fish (Psetta maxima and Clupea harengus membras). The highest concentrations of tGSH were recorded in the shrimp hepatopancreas (7.21?±?0.011 μmol g?1 wet weight), in herring liver (2.85?±?0.025 μmol g?1), and in turbot liver (1.86?±?0.063 μmol g?1). In turn, the highest concentrations were reported for GSSG in the muscle of shrimp (0.140?±?0.000204 μmol g?1), and in the testis of turbot (0.063?±?0.000170 μmol g?1) and herring (0.009?±?0.000015 μmol g?1). We also investigated seasonal changes in the concentrations of glutathione in the muscle of C. crangon shrimp in the annual cycle. The lowest values of total glutathione were recorded during spring and autumn, which could be correlated with the increase in lipid peroxidation and oxidative stress.  相似文献   

3.
BACKGROUND: Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days. RESULTS: The sensory acceptability limit was 11–12, 6–7 and 7–8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB‐N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g?1 for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB‐N values of about 25 mg 100 g?1 should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K‐values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P > 0.05) for gonads with the three treatments. CONCLUSION: Gonads with oxygen packaging had lower sensory demerit point (P < 0.05) and TVB‐N values (P < 0.05), and higher relative ATP content (P < 0.01) and K‐values (P < 0.05), than that with nitrogen or air packaging, with an extended shelf life of 4‐5 days during storage in artificial seawater at 5 ± 1 °C. Copyright © 2011 Society of Chemical Industry  相似文献   

4.
Myrosinase activity in partially purified extracts of 12 cruciferous vegetables and an acetone powder preparation of Sinapis alba L. (white mustard) was determined by the initial rate of glucose formation from glucosinolate hydrolysis using a coupled assay. Of the species studied Raphanus sativus L. (radish, 12.8±0.7 μmol min?1g?1 powdered tissue) had the greatest myrosinase activity, and Brassica campestris L. ssp. rapifera (turnip) and Nasturtium officinalis R.Br. (watercress) (0.6±0.1 and 0.8±0.03 μmol min?1g?1 powdered tissue respectively) the least. The sub-species of Brassica oleracea studied all had similar myrosinase activity (ca 2.5±0.2μmolmin?1g?1 powdered tissue) except B. oleracea L. var. gemmifera D.C. (Brussels sprouts) and B. oleracea L. var. capitata L. (white cabbage) which had higher activities (7.6±0.1 and 5.2±0.2μmol min?1g?1 powdered tissue respectively). The effect of ascorbate concentration upon the myrosinase activity of six of the crucifers studied and the white mustard preparation, revealed that the ascorbate concentration necessary to promote maximal activity varied with species. A concentration of 0.9mM ascorbate maximally activated radish and turnip myrosinase, while red cabbage, watercress, white mustard and Brussels sprouts were maximally activated at 2.0, 3.0, 5.0 and 0.7–1.0mM ascorbate respectively. Two peaks of maximal myrosinase activity, occurring between 0.9 and 1.0mM and at 3.0mM ascorbate, were found for B. oleracea L. var. botrytis L. subvar. cauliflora D.C. (cauliflower).  相似文献   

5.
BACKGROUND: Recently much attention has been paid to biologically active plants because of their low production cost and fewer adverse effects compared with chemical drugs. In the present investigation the bioactivity of Phyllanthus niruri ethanol and aqueous extracts was evaluated in vitro. RESULTS: The ethanol extract of P. niruri showed a high level of flavonoid content (123.9 ± 0.002 mg g?1), while the aqueous extract showed the highest 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH; IC506.85 ± 1.80 µmol L?1) and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS; 46.44 ± 0.53 µmol L?1) free radical scavenging activities with high phenol content (376 ± 0.02 mg g?1) and elevated levels of ferric reducing antioxidant power (FRAP; 23 883 ± 0.019 mmol g?1) with excellent antibacterial activity against Staphylococcus aureus (20 mm inhibition zone) and Streptococcus agalactiae (12 mm inhibition zone), respectively, in addition to the best immune activation potential of human peripheral blood mononuclear cells (450.5%). CONCLUSIONS: It is clear from our results that both extracts of P. niruri has excellent bioactivity roles via elevated levels of antibacterial, antioxidant and percentage of peripheral blood mononuclear cell proliferation, which could lead to the development of medications for clinical use. Copyright © 2012 Society of Chemical Industry  相似文献   

6.
The characteristics and stability of natural actomyosin (NAM) from rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala) were investigated. The total extractable actomyosin (AM) was higher (7.60 mg ml?1) in the case of rohu compared with that from catla and mrigal (5 mg ml?1). Although the specific AM ATPase activity was similar (0.43–0.5 µmol P min?1 mg P?1) among the three species, the total ATPase activity was lower in mrigal (25 µmol g?1 meat) compared with the other species (37 µmol g?1 meat). The inactivation rate constants (kd) of AM Ca ATPase activity showed differences in the stabilities of actomyosin among these fish, the actomyosin from catla being least stable. The NAM from these species was stable up to 20 °C at pH 7.0. Catla AM became unstable at 30 °C, while rohu and mrigal AM could withstand up to 45 °C. The thermal denaturation with respect to solubility, turbidity, ATPase activity, sulphhydryl group and surface hydrophobicity showed noticeable changes at around these temperatures. Copyright © 2004 Society of Chemical Industry  相似文献   

7.
Muscle metabolites in resting, tank acclimated snapper, Pagrus auratus, were monitored for 72 hr postmortem and compared with values from exercised or commercially caught fish. The physiological status of the live animal was quantified by plasma cortisol and blood chemistry. Cortisol levels were lowest in unstressed controls (6.8 ± 2.1 ng mL?1) while exercised laboratory fish had highest levels (67.7 ± 11.2 ng mL?1). Control fish maintained a constant K-value for 72 hr in chilled storage; all other groups had significant increases. Onset of rigor development and muscle ATP depletion was delayed in unstressed fish and was more rapid in line-captured than exercised fish. Commercial users minimizing stress would maintain high flesh quality.  相似文献   

8.
Harmful algae blooms (HABs) are the main source of marine toxins in the aquatic environment surrounding the austral fjords in Chile. Huichas Island (Aysén) has an history of HABs spanning more than 30 years, but there is limited investigation of the bioaccumulation of marine toxins in the bivalves and gastropods from the Region of Aysén. In this study, bivalves (Mytilus chilenses, Choromytilus chorus, Aulacomya ater, Gari solida, Tagelus dombeii and Venus antiqua) and carnivorous gastropods (Argobuccinum ranelliformes and Concholepas concholepas) were collected from 28 sites. Researchers analysed the accumulation of STX-group toxins using a LC with a derivatisation post column (LC-PCOX), while lipophilic toxins (OA-group, azapiracids, pectenotoxins and yessotoxins) were analysed using LC-MS/MS with electrospray ionisation (+/–) in visceral (hepatopancreas) and non-visceral tissues (mantle, adductor muscle, gills and foot). Levels of STX-group and OA-group toxins varied among individuals from the same site. Among all tissue samples, the highest concentrations of STX-group toxins were noted in the hepatopancreas in V. antiqua (95 ± 0.1 μg STX-eq 100 g?1), T. dombeii (148 ± 1.4 μg STX-eq 100 g?1) and G. solida (3232 ± 5.2 μg STX-eq 100 g?1; < 0.05); in the adductor muscle in M. chilensis (2495 ± 6.4 μg STX-eq 100 g?1; < 0.05) and in the foot in C. concholepas (81 ± 0.7 μg STX-eq 100 g?1) and T. dombeii (114 ± 1.2 μg STX-eq 100 g?1). The highest variability of toxins was detected in G. solida, where high levels of carbamate derivatives were identified (GTXs, neoSTX and STX). In addition to the detected hydrophilic toxins, OA-group toxins were detected (OA and DTX-1) with an average ratio of ≈1:1. The highest levels of OA-group toxins were in the foot of C. concholepas, with levels of 400.3 ± 3.6 μg OA eq kg?1 (< 0.05) and with a toxic profile composed of 90% OA. A wide range of OA-group toxins was detected in M. chilensis with a toxicity < 80 μg OA eq kg?1, but with 74% of those toxins detected in the adductor muscle. In all evaluated species, there was no detection of lipophilic toxins associated with biotransformation in molluscs and carnivorous gastropods. In addition, the STX-group and OA-group toxin concentrations in shellfish was not associated with the presence of HAB. The ranking of toxin concentration in the tissues of most species was: digestive glands > mantle > adductor muscle for the STX-group toxins and foot > digestive gland for the OA-group toxins. These results gave a better understanding of the variability and compartmentalisation of STX-group and OA-group toxins in different bivalve and gastropod species from the south of Chile, and the analyses determined that tissues could play an important role in the biotransformation of STX-group toxins and the retention of OA-group toxins.  相似文献   

9.
Concentrations of five toxic metals were determined in two fish species from Turkish cities during 2010–2011. The obtained lead concentrations for all of the studied Trachurus trachurus (mean 777 μg kg?1) and Cyprinus carpio (mean 439 μg kg?1) samples were found to be higher than the maximum level (ML) of 300 μg kg?1, while Cd concentrations in the same samples were lower than the ML. Mean chromium (501 μg kg?1), Ni (272 μg kg?1) and Cu (785 μg kg?1) concentrations in T. trachurus were significantly higher than in C. carpio (336 μg Cr kg?1, 229 μg Ni kg?1 and 394 μg Cu kg?1), similar to those of Pb and Cd. Measured Pb concentrations in T. trachurus tissues are significantly higher than the ML, while those of Cd in both T. trachurus and C. carpio species were lower than the ML values.  相似文献   

10.
The aim of this work was to study the proximate composition and the bioactive profile of Bifurcaria bifurcata. It contains 73.31 ± 0.69% of moisture, 8.57 ± 0.11 g per 100 g dry weight (d.w.) of protein, 5.81 ± 0.14 g per 100 g d.w. of lipid content and 30.15 ± 0.00 g per 100 g d.w. of ash. The polyunsaturated fatty acids were the most abundant fatty acid (FA), accounting for 2426.56 mg per 100 g which represents 41.77% of the total FA. The methanolic fraction showed high quantity of polyphenols (220.01 ± 0.010 phloroglucinol equivalents g?1 extract), DPPH radical reduction capacity (EC50:58.82 μg mL?1) and oxygen radical absorbent capacity (3151.35 ± 119.33 μmol Trolox equivalents g?1 extract). The highest antimicrobial effect was observed against Pseudomonas aeruginosa (11.3 ± 1.5 mm) and Saccharomyces cerevisiae (IC50:17.07 μg mL?1) induced by methanolic and dichloromethane fractions, respectively. Dichloromethane fraction revealed the highest antitumor activity on Caco‐2 and HepG‐2 cells. Bifurcaria bifurcata can be a promising source of bioactive compounds and functional ingredients.  相似文献   

11.
This study aimed to establish an analytical method for α‐dicarbonyl compounds (α‐DCs) including glyoxal, methylglyoxal and diacetyl, to determine the content of α‐DCs in 101 various alcoholic beverages using gas chromatography–nitrogen phosphorous detector (GC‐NPD) and to perform exposure assessment. The limit of detection and limit of quantification for α‐DCs were 0.05–0.22 and 0.15–0.70 μg g?1, respectively. The accuracy and precision were validated in five matrices. The raspberry fruit wine had the highest value at 139.74 μg g?1 total α‐DCs. The lowest α‐DC concentration among the beverages was detected in rice wine (Makgeolli) at 1.59 μg g?1. The levels of α‐DCs in various samples were detected as follows: 1.59–56.68 μg g?1 in rice wine (Makgeolli), 2.73–16.77 μg g?1 in beer, 8.22–139.74 μg g?1 in fruit wine and 8.17–91.56 μg g?1 in rice wine (Cheongju). The estimated daily intake of α‐DCs in the intake‐only group and population group was calculated as 4.22–97.94 μg kg?1 bw day?1 and 0.28–7.13 μg kg?1 bw day?1, respectively.  相似文献   

12.
A study to quantify the free glutamic acid content of six processed foods, 44 dishes and 26 condiments available in Malaysia was performed using high-performance liquid chromatography with a fluorescence detector (HPLC-FRD). Recovery tests were carried out with spiked samples at levels from 6 to 31 mg g?1. High recovery in different matrices was achieved ranging from 88% ± 13% to 102% ± 5.12%, with an average of 97% ± 8.92%. Results from the study revealed that the average free glutamic acid content ranged from 0.34 ± 0.20 to 4.63 ± 0.41 mg g?1 in processed foods, while in prepared dishes it was as low as 0.24 ± 0.15 mg g?1 in roti canai (puffed bread served with curry or dhal) to 8.16 ± 1.99 mg g?1 in dim sum (a small casing of dough, usually filled with minced meat, seafood, and vegetables, either steamed or fried). Relatively, the content of free glutamic acid was found to be higher in condiments at 0.28 ± 0 mg g?1 in mayonnaise to 170.90 ± 6.40 mg g?1 in chicken stock powder.  相似文献   

13.
Isoflavone glucosides and aglucons in various soybean varieties (Chiang Mai‐60, S.J.‐5, Chiang Mai‐2, Srisumrong‐1, and Nakhonsawan‐1) harvested from dry vs. rainy seasons were quantified. Isoflavone contents of all soy germs ranged from 16.5 to 30.6 μmol g?1. Regardless of varieties, isoflavone contents in germ of seeds from dry season were higher (P < 0.05) than those from rainy season. The Chiang Mai‐60 germ, having the highest isoflavone content (30.6 μmol g?1), was selected for germ flour production. Freeze‐dried germ flour contained higher isoflavone aglucons (17.72 μmol g?1 daidzein; 6.48 mg g?1 glycitein; 4.28 μmol g?1 genistein) than those (15.07; 5.59; 3.41) of drum‐dried germ flour. However, isoflavone glucoside contents in freeze‐dried germ flour (3.27 μmol g?1 daidzin; 1.86 μmol g?1 glycitin; 1.41 μmol g?1 genistin) were lower than those (5.22; 3.15; 1.89) of drum‐dried germ flour. Total isoflavone contents of drum‐dried and freeze‐dried germ flours were comparable (34.32 vs. 35.02 μmol g?1) but more than that (30.16 μmol g?1) of unprocessed germ flour.  相似文献   

14.
In the present study, lipid was extracted from scallop (Patinopecten yessoensis) viscera by using the enzyme‐assisted solvent method and the supercritical carbon dioxide (SC‐CO2) method. Soxhlet extraction with ethyl ether produced a yield of 23.7 ± 0.6 g of lipid 100 g?1 of dry matter. Enzyme‐assisted solvent extraction allowed recovering 60.6 ± 1.5% of P. yessoensis viscera lipid from the samples treated with papain, whereas a lipid recovery rate of 78.3 ± 0.6% was achieved by SC‐CO2 extraction. The lipid extracted was divided into the unsaponifiable fraction (sterol) and the saponifiable fraction (fatty acid) and analysed by gas chromatography mass spectrometry. Results indicated that the fatty acid composition and sterol composition for lipids extracted by different methods were slightly different. Eicosapentaenoic acid and docosahexaenoic acid were dominant polyunsaturated fatty acids accounting for 35–40% of the total fatty acid.  相似文献   

15.
BACKGROUND: Horseradish plants (Armoracia rusticana) contain high concentrations of glucosinolates. Former studies have revealed that Armoracia plants cultivated in vitro have markedly lower glucosinolate concentrations than those grown in soils. Yet, these studies neglected that the sulfate concentration in the growth medium may have had a strong impact on glucosinolate metabolism. Accordingly, in this study horseradish in vitro plants were cultivated with differing sulfate concentrations and the glucosinolate concentrations were quantified by ion pair HPLC. RESULTS: Cultivation in 1.7 mmol L?1 sulfate (as used in the prior studies) resulted in the accumulation of 16.2 µmol g?1 DW glucosinolates, while the glucosinolate concentration increased to more than 23 µmol g?1 DW when 23.5 mmol L?1 sulfate was used in the medium. Correspondingly, the glucosinolate concentration decreased to 1.6 µmol g?1 DW when sulfate concentration was lowered to 0.2 mmol L?1. CONCLUSION: Since the glucosinolate accumulation in relation to the sulfate concentration follows a typical saturation curve, we deduce that the availability of sulfate determines the glucosinolate concentration in horseradish in vitro plants. © 2012 Society of Chemical Industry  相似文献   

16.
Sixty calves of the Dutch Friesian (FH) breed were stunned mechanically. Without previously having been stunned, another 30 calves were stuck according to the Jewish rite. Upon opening of the skulls (1–2 h post mortem) brains of mechanically stunned calves were collected either conventionally (n = 30) or ‘hygienically’ (n = 30), i.e. using a fresh pair of surgical gloves during each removal to avoid cross contamination. For ritually slaughtered animals only the hygienic procedure was followed. Samples of 10 g were excised from undamaged hemispheres and in the mechanically stunned treatment group also from the site of impact of the captive bolt. After storage in polystyrene trays at 3 ± 1°C for 7 days sampling was repeated. Bacteriological examination included the assessment of aerobic colony counts at 30°C for 3 days (ACC-30) and 4°C for 14 days (ACC-4) and Enterobacteriaceae colony counts at 37°C for 20 h (ECC). In conventionally collected samples the ACC-30 and ACC-4 were 3.8 and 3.0 log10 cfu g?1 at day 1 and 6.2 and 6.4 log10 cfu g?1 at day 8. With hygienic collection these counts were reduced by approximately 1 log unit. Whilst by conventional practice the ECCs, at day 1 and 8 were 2.6 and 4.8 log10 cfu g?1 these counts were 1.8 and 2.6 log10 cfu g?1 for hygienic practice. In samples excised from the site of impact of the captive bolt the hygienic procedure had similar, though less marked effects. On day 1 brains from ritually slaughtered animals had a bacteriological contamination similar to that found in the hemispheres of mechanically stunned calves. However, whilst at day 8 their mean ECCs were 3.4 and 3.5 log10 cfu g?1 the percentages of plates ‘positive’ for Enterobacteriaceae were only 10% in the ritually vs. 53% in the mechanically stunned group. The Enterobacteriaceae in this case were composed of psychrotrophic non-pathogenic genera of environmental origin. Salmonella was not isolated from any sample.  相似文献   

17.
It is considered that waterjet stunning may be a humane stunning method to apply in slaughter facilities. An experiment was conducted in a slaughterhouse to examine the effects of waterjet stunning combined with electroimmobilization during exsanguination on the occurrence of haemorrhages in the muscles and on meat quality.Slaughter pigs (n = 31) were stunned by waterjet (3900 bar) in a V-type restrainer and immobilized electrically (40 V) during exsanguination. Control animals (n = 39) were stunned automatically and electrically (600 V) using the same restraint device.At 45 min post mortem the pH in the semimembranosus (SM) and longissimus dorsi (LD) muscles was significantly lower (p < 0·01), while rigor mortis and temperature in the SM and LD were significantly higher (p < 0·05 and p < 0·01, respectively) in the carcasses of pigs stunned with the waterjet as compared to control pigs. At 18 h post mortem the ultimate pH of the LD was lower (p < 0·05), while scatter (fibre optic probe) and filter paper test values of the LD were higher (p < 0·01) in carcasses of pigs stunned with the waterjet. Fewer haemorrhages were observed in the shoulders of pigs stunned with the waterjet.The results of this experiment suggest that waterjet stunning, when combined with electroimmobilization, may be a suitable method to stun pigs in a slaughterhouse. However, further studies are required to improve the meat quality.  相似文献   

18.
In this study, we describe the extraction of different valuable compounds from winter melon seeds using supercritical carbon dioxide extraction combined with pressure swing technique (SCE-PST). The effects of the extraction variables, namely pressure, holding time (HT), and continuous extraction time (CT), were optimized by response surface methodology (RSM) to maximize the crude extraction yield (CEY). The optimal conditions were at pressure of 181.35 bar, HT of 9.93 min, and CT of 50.14 min. Under these conditions, the experimental CEY was 235.70?±?0.11 mg g?1 with a relatively strong antioxidant activity (64.42?±?0.21 % inhibition of DPPH· radicals, 67.36?±?0.34 % inhibition of ABTS·+ radicals) and considerable amount of phenolic compounds (42.77?±?0.40 mg gallic acid equivalent/g extract). The high-performance liquid chromatography (HPLC) analysis revealed that the bioactive phenolic compounds increased significantly using PST (p?<?0.05), where gallic acid had the highest concentration (0.688?±?0.34 mg g?1). The extract obtained using optimal SCE-PST conditions contained more than 83.65 % total unsaturated fatty acids (UFAs) and linoleic acid accounted for 67.33?±?0.22 % in the total extract. From the results, the SCE efficiency in terms of extract quantity and quality has been enhanced significantly applying PST. Finally, the results were compared with previous published findings using supercritical carbon dioxide, ultrasound-assisted, and Soxhlet extraction. It was found that higher CEY could be achieved using Soxhlet extraction even through the quality of SCE-PST extracts in terms of antioxidant activity and phenolic compounds was better.  相似文献   

19.
The changes in the microbiological and biochemical quality of grouper (Epinephelus chlorostigma) stored in dry ice (solid carbon dioxide) were investigated. Fresh fish stored in dry ice at the ratio of 1:1 (wt/wt) were found to be organoleptically suitable for consumption when they were stored for 30 h without re‐icing. Fish stored in water ice (as control) at the ratio of 1:1 (wt/wt) and in a combination of dry ice and water ice at the ratio of 1:0.2:0.5 (wt/wt/wt) were acceptable up to 18 and 24 h, respectively. Total bacterial load ranged from 105 to 107 CFU g?1, while total psychrophiles from 103 to 106 CFU g?1. Total lactics were found in the levels of 102–104 CFU g?1. Total volatile basic nitrogen contents were within the limit of acceptability in all the three treatments, whereas trimethylamine nitrogen content exceeded the limit (15 mg%) and hypoxanthine content was 11.11 mg (100 g)?1 on the 30 h in grouper stored only in dry ice. Lowest temperature of ?5.8 °C was recorded in grouper stored only in dry ice. Hundred percent CO2 environment within the package was found in grouper that were stored in dry ice and combination of dry ice and water ice.  相似文献   

20.
Starches isolated from 23 bread wheats (Triticum aestivum) and 26 durum wheats (T. durum) contained 26.3-30.6% (mean 29.1%) total amylose, 19.3–25.1% (mean 22.9%) apparent amylose and 783–1144mg 100g?1 (mean 977 mg 100g?1) lysophos-pholipids. Gelatinisation temperatures were 57.3–64.9°C (mean 61.8°C) and enthalpies 6.4–11.8 Jg?1 (mean 9.7Jg?1) in excess water, measured by differential scanning calorimetry. There were no correlations between any of these parameters. Starch granule size distributions were determined with a Coulter Counter and 100–channel analyser. A-granule mean volumes were 1235–2585μm3 (av. 1778), modal volumes 863–1804μm3 (av. 1264), mean diameters 13.9–16.0μm (av. 13.99), and specific surface areas 0.236–0.302m2g?1. B-granule mean volumes were 35.4–100.4μm3 (av. 55.9), modal volumes 16.5–54.5μm3 (av. 27.7), mean diameters 3.66–5.07μm (av. 4.09), and specific surface areas 0.684–0.920m2g?1. The B-granule contents of the starches were 12.8–34.6% (av. 27.3) by weight (sedimentation method) and 13.0–37.3% (av. 24.0) by volume (Coulter method), the latter being the more accurate method.  相似文献   

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