共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Aningeria robusta and Terminalia ivorensis of diameters ranging from 10 cm to 25 cm were examined. The following results were obtained: The overall (sapwood and heartwood
combined) moisture contents of the branchwood of both Aningeria robusta and Terminalia ivorensis were significantly greater than those of their corresponding stemwood, with the branchwood of Terminalia ivorensis being the highest. It was also observed that the overall specific gravity of the branchwoods of both species was higher than
that of the corresponding stemwood, with the branchwood of Aningeria robusta exhibiting the highest specific gravity. Detailed analyses of moisture content distribution and specific gravity of the heartwood
and sapwood of Aningeria robusta and Terminalia ivorensis are also presented. 相似文献
3.
4.
彩色马铃薯"剑川红"和"转心乌"富含花色苷,为探明2种马铃薯中花色苷的体外抗氧化活性差异及其组合效果,使这种价格低廉、取材方便的食材得到更好的开发和利用。本研究以抗坏血酸(VC)为对照,采用1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基法、2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate),ABTS)自由基法、羟自由基(·OH)法、超氧阴离子自由基(O_2~-·)法等4种体外抗氧化模型评价了云南地方特色马铃薯品种"剑川红"和"转心乌"花色苷的抗氧化活性。结果表明:"剑川红"和"转心乌"的花色苷具有很好的抗氧化活性,且与质量浓度成正相关,其清除自由基的能力是抗坏血酸的10.7~31.3倍;"剑川红"和"转心乌"对4种自由基的清除能力依次为ABTS+·DPPH自由基O_2~-··OH;"转心乌"花色苷对4种自由基的清除效果比"剑川红"花色苷强;二者的花色苷之间没有拮抗作用,且有一定的协同或增效作用,协同或增效效果因自由基的不同而有所差异。 相似文献
5.
ABSTRACT: Beef tallow was fractionated either without or with solvent to obtain a highly enriched unsaturated fatty acid (USFA) fraction. Solvent fractionation at low temperature (-18 °C) successfully fractionated USFA-enriched triacylglycerol (TAG). The higher that the solute to solvent ratio was used for fractionation, the more weight yield of USFA-enriched TAG from the liquid fractions was recovered during the fractionation. USFA-enriched fraction was further esterified with lipase and medium chain fatty acid (caprylic acid). Through 2nd-step transesterification, MLM (sn-1-medium-2-long-3-mediumTAG) type of structured lipids (SL) was produced in volume. Isolated SL was characterized by reverse-phase HPLC, GC, and DSC. Synthesized SL in this study would be considered as a value-added product from renewable animal fat for nutritionally beneficial applications in food. 相似文献
6.
A study to determine the optimum conditions for enzymatic peeling of two morphologically different oranges varieties (Thomson and Mollar) was carried out. The potential enzymatic saturation of albedo (PESA) was determined by submerging the orange fruit (with perforated flavedo) in an enzymatic solution with Chinese ink and applying several vacuum pressures for different times. The PESA was evaluated using percentage of weight increase and percentage of albedo surface dyed with ink. The incubation time with the enzymatic solution (Peelzym II) necessary to obtain a final product with good quality was also optimized. After each incubation time, the evaluation of peeling efficiency was carried out. The means of visual assessment for five characteristics were chosen and scaled for peeling and final product quality. Results showed that vacuum application in pulses was more effective than in continuum. For obtaining peeled segments from the Mollar variety the best conditions were three pulses of 80 kPa with the enzymatic solution and 30 min of incubation at an atmospheric pressure of 40 °C. The best condition to obtain peeled entire orange from Thomson variety were two pulses of 53 kPa with the enzymatic solution and 40 min of incubation at an atmospheric pressure at 40 °C. 相似文献
7.
8.
‘香水梨’和‘嘉宝梨’后熟期间呼吸强度及品质指标的变化及其比较 总被引:1,自引:0,他引:1
以商业成熟的‘香水梨’和‘嘉宝梨’为试材,经室温(20±3)℃、相对湿度85%~90%条件下后熟,测定后熟期间的生理和品质指标的变化。结果表明,‘香水梨’后熟期间的呼吸强度呈典型的跃变型变化,显著高于‘嘉宝梨’,且‘香水梨’在第5天出现呼吸高峰,‘嘉宝梨’虽在第15天时有呼吸高峰出现,但变化不显著;‘嘉宝梨’的可溶性固形物含量和固酸比显著高于‘香水梨’,两者的可溶性固形物含量分别在第15天和第10天时达到最大,‘香水梨’可滴定酸含量显著高于‘嘉宝梨’,后熟期间均逐渐下降;果实色泽变化为a*值变化最明显,‘香水梨’显著高于‘嘉宝梨’,后熟期间均逐渐上升;2种梨后熟期间石细胞含量基本不变,硬度逐渐减小,质量损失率逐渐增大,均为‘香水梨’高于‘嘉宝梨’。综上所述,‘香水梨’和‘嘉宝梨’均属于跃变型果实,后熟期间果实色泽和质地等品质性状均显著提升。 相似文献
9.
In vitro antioxidant activities of the novel pentapeptides Ser‐His‐Glu‐Cys‐Asn and Leu‐Pro‐Phe‐Ala‐Met and the relationship between activity and peptide secondary structure
下载免费PDF全文
![点击此处可从《Journal of the science of food and agriculture》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ruiwen Yang Jia Wang Songyi Lin Haiqing Ye Feng Chen 《Journal of the science of food and agriculture》2017,97(6):1945-1952
10.
Gastrointestinal absorption and metabolism of hesperetin‐7‐O‐rutinoside and hesperetin‐7‐O‐glucoside in healthy humans
下载免费PDF全文
![点击此处可从《Molecular nutrition & food research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lucas Actis‐Goretta Tristan P. Dew Antoine Lévèques Gema Pereira‐Caro Maarit Rein Alexander Teml Christian Schäfer Ute Hofmann Matthias Schwab Michel Eichelbaum Alan Crozier Gary Williamson 《Molecular nutrition & food research》2015,59(9):1651-1662
11.
Katrin Zur Anke Heier Karl Werner Blaas Carsten Fauhl-Hassek 《European Food Research and Technology》2008,227(4):969-977
1H- and 13C-NMR-spectra of pistachio oil from Iran, USA and Turkey were analysed with multivariate statistics in order to classify pistachios
according to their countries of origin. The integrals of the resonances of the NMR-spectra contain information about the fatty
acid composition of pistachio oil which is supposed to reflect the climatic conditions at the crop area. Consequently, NMR-spectroscopy
was thought to be a suitable method for the distinction of those pistachio oils. Cluster analysis was found to lead to a distinction
between pistachio samples from Turkey and other countries. Principle component analysis was used to extract components from
the data, which primarily contain the information about unsaturated acyl chains in the oil and allowed to assign the samples
very well to their respective countries of provenance. Linear discriminant analysis provides similar results with low error
rate estimations. It was demonstrated that those data gained by 1H- and 13C-NMR-spectroscopy from samples with unknown provenance can be classified by principle component analysis as well as by discriminant
analysis. 相似文献
12.
Growth and Survival Differences of Vibrio vulnificus and Vibrio parahaemolyticus Strains during Cold Storage 总被引:1,自引:0,他引:1
V.E. Burnham M.E. Janes L.A. Jakus J. Supan A. DePaola J. Bell 《Journal of food science》2009,74(6):M314-M318
ABSTRACT: Vibrio vulnificus and Vibrio parahaemolyticus are the most common Vibrio species associated with seafood illness in the United States. Our study was conducted to determine if strain-to-strain differences exist in the growth and survival of 8 different V. vulnificus and V. parahaemolyticus strains at low temperatures. By day 10, V. vulnificus strain 515-4C2 had significantly higher counts ( P < 0.05) (1.97 log CFU/g) compared with strains 3315, 1007, 29306 at 5 °C, which reached nondetectable levels. At 8 °C, strain 515-4C2 had significantly higher counts ( P < 0.05) (2.23 log CFU/mL) compared with 1007, 33815, 541(O) 49C, which reached nondetectable levels. At 10 °C, only V. vulnificus strain 33815 reached nondetectable levels. At 5 °C, V. parahaemolyticus strain 541(O) 57C had the highest counts (5.28 log CFU/g) by day 10 while strain 33847 had significantly lower counts (3.46 log CFU/g). After 10 d at 8 °C, V. parahaemolyticus strain M350A had the highest counts (7.97 log CFU/mL) while strain 541(O) 57C had the lowest counts (4.80 log CFU/mL). At 10 °C, V. parahaemolyticus strain NY477 had significantly higher counts ( P < 0.05) with 8.31 log CFU/mL compared with strain 33847, which had the lowest counts (6.77 log CFU/mL). Our research has shown that various V. vulnificus and V. parahaemolyticus strains vary in their ability to survive and grow at refrigeration temperatures. 相似文献
13.
The effects of refrigerated storage at 2 °C and 95% RH and processing treatments on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries were investigated. During refrigerated storage, total phenolics (TPC), total monomeric anthocyanins (ACY), and radical scavenging activity (RSA) fluctuated in ‘Marion’, but TPC and ACY continuously declined in ‘Evergreen’. Oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) decreased by 20% and increased by 19% in ‘Evergreen’, respectively after 7-d refrigerated storage, while no changes (P > 0.05) in ‘Marion’ were observed. Compared with frozen samples, freeze-dried ‘Evergreen’ had higher TPC (21%), ACY (5.5%), and RSA (14%), while hot-air dried “Marion” had lower ACY (56%), ORAC (37%), and FRAP (27%) and hot-air dried ‘Evergreen’ had lower TPC (37%), ACY (84%), and RSA (13%). ORAC and FRAP in canned ‘Marion’ was 21-61% lower than that of frozen samples. Jam also had lower TPC and ACY (67-84%), RSA (˜80%), and ORAC and FRAP (65-77%) values than frozen ones in both varieties (P < 0.05). The 6-mo post-process room storage had little effect on the bioactive compounds of frozen and freeze dried samples, but reduced ACY in hot-air dried, canned, and jam samples, and antioxidant capacities of all samples (P < 0.05). 相似文献
14.
Chemical composition of fresh and conserved<Emphasis Type="Italic"> Agaricus bisporus</Emphasis> mushroom 总被引:1,自引:0,他引:1
János Vetter 《European Food Research and Technology》2003,217(1):10-12
A comparison of chemical constituents of fresh and conserved samples of Agaricus bisporus was made. The crude protein and crude fat contents were practically unchanged but a decrease in dry matter content and a remarkable decrease in ash content were found. The concentrations of some minerals (Cd, Mn, Zn) were unchanged, indicating that the solubility was not good or the soluble, free forms of element were not present in large amounts. Another group of elements (B, Cu, K, Mg, P, Se) showed a decrease to varying extents because the presence of the free forms of the elements was high. Unfortunately this tendency was with regard to elements that belong to the biologically more valuable mineral components (K, P, Mg). Higher Cr-, Ni-, and Hg-concentrations of conserved mushroom samples are not beneficial characteristics. The extremely high Na level of the conserves (and therefore the changed, unbeneficial K/Na rate) is a hazardous factor to some groups of consumers (patients of high blood pressure and in general people with cardiovascular problems). According to the presented data there are some negative consequences (most of all the changes in minerals) derived from the classical technology of conservation which diminish the nutritional value of the mushroom. 相似文献
15.
ABSTRACT: Textural and physical properties of acetic acid-induced and salt-induced surimi gels were evaluated. The addition of 2 to 3% acetic acid significantly decreased the shrinkage and total expressible fluid and increased firmness compared to 0.5% acetic acid added. Acid-induced gels without starch were significantly firmer than those with starch and salts. There was no peak in storage modulus with the addition of acid in the temperature range of 32 to 43 °C, suggesting that the acid-induced gelation did not require setting as the salt-induced one. Partial substitution (1%) of KCl for NaCl did not change the storage modulus of the sol during heating and gel firmness. However, KCl and NaCl weakened the firmness of the acid-induced gel. 相似文献
16.
Nabaweya A. Ibrahim Souad El-Gengaihi H. Motawe S. A. Riad 《European Food Research and Technology》2007,224(4):483-488
Five labdane diterpenoids, austroinulin, iso-austroinulin, sterebin E, sterebin E acetate, and sterebin A acetate, along with hydrocarbons, aliphatic alcohols, β-amyrin,
β-sitosterol and stigmasterol were isolated from the chloroform soluble fraction of the methanol extract of Stevia rebaudiana leaves. Chlorogenic and caffeic acids were isolated from the EtOAc fraction. All the isolated compounds were identified using
spectral tools. The chloroform and methanol extracts proved significant anti-inflammatory effect and caused marked inhibition
of carrageenan-induced paw oedema in rats. 相似文献
17.
18.
Paired preference tests of liking require consumers to specify which of two foods are preferred or whether there is no preference. For ‘Buying’ preference tests, consumers specify which of two foods they are more likely to buy or whether they might buy either or neither. For ‘Choosing’ preference tests, consumers specify which of two foods they are more likely to choose when offered both, or whether they might choose both or neither. The first test is designed to predict greater degrees of liking, the second to predict buying behavior and the third to predict choice behavior. Yet, test results may not necessarily predict ‘real life’ behavior once consumers have left the testing situation; the ‘test’ preferences may not be ‘operational’. To validate the predictive ability of such tests, consumer behavior should be monitored for several months. Another approach is to allow consumers to take away some of the foods used in the test and observe what they take away. Consumers of potato chips were required to taste chips whose flavor and appearance were obviously different. A first group (N = 107) were given ‘Liking’, ‘Buying’ and ‘Choosing’ preference tests for two palatable types of chip. After the test, out of sight of the experimenter, consumers were presented with two rows of plain plastic ‘snack’ bags, filled with the chips used in the test. They could take away either two bags of the same type of chip (a ‘Take Away’ preference) or one of each type (no ‘Take Away’ preference) or take neither (rejection). They were also subtly questioned regarding whether they were going to consume the chips themselves or were going to share them with friends. A second group (N = 103) repeated the experiment. However, for these consumers, one type of chip was unpalatable. In general, ‘Buying’ preferences corresponded more to ‘Take Away’ preferences while ‘Liking’ and ‘Choosing’ preferences showed little correspondence. For the palatable chips, the preferences were spread more evenly than for the case where one type of chip was undesirable. In this latter case, approximately 50% of consumers were consistent over all tests in choosing the palatable chip. This might suggest operational preferences. ‘Take Away’ preferences suggested low predictability for paired preference tests of liking, choosing and buying. ‘Take Away’ preferences are not a substitute for monitoring consumer behavior for several months but they are a step in the right direction. 相似文献
19.
Ute Schweiggert Christina Kurz Andreas Schieber Reinhold Carle 《European Food Research and Technology》2007,225(2):261-270
The stability of non-esterified carotenoids and carotenoid esters in paprika and chilli powder as affected by various processing
treatments and storage conditions were studied. For this purpose, freshly harvested chilli and paprika pods were minced, immediately
heated at 80, 90 and 100 °C for 5 and 10 min, respectively, and lyophilised. Alternatively, thermal treatment prior to mincing
was applied. Processing resulted in a 25–34% loss of the initial carotenoid contents in chilli and 20–53% in paprika. Degradation
of individual non-esterified carotenoids, mono- and diesters was monitored, generally showing an increased processing stability
of mono- and diesters compared to their non-esterified counterparts. Capsanthin, capsorubin, zeaxanthin and β-cryptoxanthin
mono- and diesters esterified with saturated fatty acids displayed similar stabilities, whereas susceptibility of the non-esterified
pigments to degradation differed considerably. During storage over 4 months at ambient temperature pigment contents dropped
by 16.7 and 9.6% in chilli and by 39.7 and 38.8% in paprika powders with and without illumination, respectively. 相似文献
20.
Yogesh P. Gadekar Anne S. R. Anjaneyulu Rajendran Thomas Sanjod Kr. Mendiratta & Napa Kondaiah 《International Journal of Food Science & Technology》2009,44(9):1763-1769
Chicken soup was made from the broth collected after the pressure cooking of deboned chicken frames (bones). The quality of stored chicken soup (S1) was compared with the soup prepared from the stored chicken broth (S2) at refrigerated (4 ± 1 °C) and frozen (−18 ± 1 °C) storage up to 12 and 90 days, respectively. Thiobarbituric acid reactive substances values and microbial counts were significantly ( P < 0.01) higher in stored soup (S1) compared with fresh soup (S2). Psychrotrophs and coliforms were not detected. Appearance and odour scores of broth were satisfactory throughout the storage. Sensory attributes were rated better for fresh soup (S2) made from stored broth than stored soup (S1) but all the attributes were decreased with increasing storage period. The stored soup was acceptable up to 9 and 90 days in refrigeration and frozen storage respectively, while the soup made from refrigerated stored broth was acceptable for 12 days. 相似文献