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1.
The cooked odor concentrate from precooked krill was obtained by a simultaneous distillation and extraction system. The resulting odor concentrate was separated into basic, carbonyl and carbonyl-free fractions. Each fraction was analyzed by gas chromatography and gas chromatography-mass spectrometry. Fifty seven compounds, including 3 pyridines, 10 pyrazines, 6 thiazoles, 3 dihydro-4H-1,3,5-dithiazines, 11 aldehydes, 10 ketones, 4 alcohols, 6 hydrocarbons and 4 other compounds were identified. Twenty two of these compounds were newly found as the odor components of krill. The low molecular aldehydes, which are known to be a part of the precursors of the secondary formation of the cooked odor, were also investigated by thin layer chromatography. Ethanal, propanal and butanal were newly detected.  相似文献   

2.
The volatile flavor components of Kumazasa (Sasa albo-marginata) were studied by headspace and steam distillation analyses. Thirty nine and 90 components were identified in the headspace and steam distillation concentrate respectively by GC and GC-MS. The identified components include 7 hydrocarbons, 23 alcohols, 14 aldehydes, 8 ketones, 17 phenols and 14 acids.

The components which are believed to contribute to the characteristic flavor of Kumazasa are deduced to be: 1-penten-3-ol, trans-2-hexenal, 1-hexanol, cis-3-hexen-1-ol, cyclohexanol, α-ter-pineol, 4-octanolide and β-ionone.  相似文献   

3.
The steam volatile neutral fraction of tobacco smoke condensates was separated into n-hexane, nitromethane and 1:4 water-methanol soluble fractions by solvent partition.

2.methyl-4-hydroxy-2-hexenoic acid lactone, dihydroactinidiolide and phthalide were isolated from the 1:4 water-methanol soluble fraction, the highly polar portion of the steam volatile neutral fraction was designated as the M fraction.

By continuing analysis of the M fraction from a previous paper, benzyl alcohol, phenyl-ethyl alcohol, pyrrole-2-aldehyde, α-pyrrylmethylketone, α-pyrrylethylketone, α-carbomethoxypyrrole, pyrrole-2-carbonitrile, methyl-pyrrole-2-carbonitrile, 3-methyl-, 3-ethyl-, 3-n-propyl-, 2,3-dimethyl-, 2-ethyl-3-methyl-2-cyclopentene-1-one and norsolanadione were identified.

Identification of the compounds was based on the spectroscopic method (IR, MS, UV and GC-MS) and gas chromatographic analysis.  相似文献   

4.
为了研究苍术麸炒前后挥发油的化学成分及降血糖活性的变化,采用水蒸气蒸馏法提取苍术生品和麸炒品的挥发油,用气相色谱-质谱技术分析,并采用体外α-葡萄糖苷酶抑制模型进行酶抑制活性研究.结果表明生苍术麸炒后挥发油含量显著降低,烯类、苯类、萘类及环己烯类化合物的显著减少,而[2R-(2α,4aα,8aβ)]-十氢-α,α,4a-三甲基-8-亚甲基-2-萘甲醇和联苯甲酯明显增加;α-葡萄糖苷酶活性降低,抑制强度依次为生苍术>麸炒苍术>阿卡波糖(阳性对照).表明苍术挥发油有较好的抑制α-葡萄糖苷酶活性作用.  相似文献   

5.
Abstract

Fifteen Murrah buffalo calves (age about 10 months, 163 – 176 kg BW) were divided into three groups. Group I (Control) was fed a complete feed mixture consisted of 50% wheat straw and 50% concentrate mixture (contained per kg: maize 330 g, groundnut cake 210 g, mustard cake 120 g, wheat bran 200 g, de-oiled rice bran 110 g, mineral mixture 20 g and common salt 10 g) along with 2 kg green oats per animal and day to meet the vitamin A requirements. Calves of Groups II and III were fed with the Control diet supplemented with Orpinomyces sp. C-14 and Piromyces sp. WNG-12 cultures, respectively. The digestibility of DM was significantly highest with Piromyces sp. WNG-12 in Group III (62.2%) followed by Orpinomyces sp. C-14 in Group II (60.3%), and Control (53.5%). A similar pattern of increase in digestibility of crude protein and cell-wall contents was observed in treatment groups. The digestible energy in terms of percent total digestible nutrients was also significantly enhanced in Groups II (56.6%) and III (59.9%) when compared to Control (49.2%). The rumen fermentation parameters such as pH and NH3-N were found to be lower, whereas total nitrogen, tricarboxylic acid precipitable-nitrogen, total volatile fatty acids and zoospore counts per millilitre of rumen liquor were significantly higher in fungal administered groups. After administration of fungal cultures, improvements of animal growth rate (i.e. body weight gain) and feed efficiency were also observed.  相似文献   

6.
The aim of this study was to evaluate fermented rice bran phospholipids, lipids and fatty acid content in a fermentation solid system with Rhizopus oryzae fungus. For this, aliquots were withdrawn every 24h over 120 h. The content of phospholipids was determined by colorimetric method. Esterified fatty acids were separated by gas chromatography, then identified and quantified. The total lipids from fermented rice bran (FB) decreased from 20.4% to 11.2% in the range between 0 h and 120 h of fermentation while phospholipid contents were increased up to 2.4 mg P g(lipid)(-1). In fermented bran, oleic, palmitic and linoleic acids prevailed, with a decrease in saturated fatty acids (20%) and increase in the unsaturated ones (5%). This study showed that rice bran fermentation with R. oryzae can be applied to the production of phospholipids altering the saturated to unsaturated fatty acid ratio.  相似文献   

7.
The production of fatty acid methyl esters (FAMEs) by a two-step in-situ transesterification from two kinds of rice bran was investigated in this study. The method included an in-situ acid-catalyzed esterification followed by an in-situ base-catalyzed transesterification. Free fatty acids (FFAs) level was reduced to less than 1% for both rice bran A (initial FFAs content = 3%) and rice bran B (initial FFAs content = 30%) in the first step under the following conditions: 10 g rice bran, methanol to rice bran ratio 15 mL/g, H2SO4 to rice bran mass ratio 0.18, 60 °C reaction temperature, 600 rpm stirring rate, 15 min reaction time. The organic phase of the first step product was collected and subjected to a second step reaction by adding 8 mL of 5 N NaOH solution and allowing to react for 60 and 30 min for rice bran A and rice bran B, respectively. FAMEs yields of 96.8% and 97.4% were obtained for rice bran A and rice bran B, respectively, after this two-step in-situ reaction.  相似文献   

8.
The changes in moisture content, storage mycoflora and aflatoxin B1 (AFB1) in bran from untreated or raw rice (Rr) and parboiled rice (Pbr) stored in small lots in polyethylene bags were studied at 15-day intervals up to 60 days, using five lots of each type of bran. Deterioration was more rapid with reference to all the three parameters, in Rr bran compared to Pbr bran, the former becoming completely overgrown and caked with fungi by the end of 60 days.Aspergillus flavus was the dominant fungus in Pbr bran, whereasA. candidus andTrichoderma viride were abundant in Rr bran. The frequency of incidence as well as concentration of AFB1 increased with storage time in both types of bran, but the rate of increase as well as overall concentration were much higher in Rr bran. Thus raw rice bran is unsuitable for prolonged storage.Abbreviations AFB1 aflatoxin B1 - MC moisture content - Pbr parboiled rice - Rr raw rice  相似文献   

9.
Value-added processing with respect to rice milling has traditionally treated the rice bran layer as a homogenous material that contains significant concentrations of high-value components of interest for pharmaceutical and nutraceutical applications. Investigators have shown that high-value components in the rice bran layer vary from differences in kernel-thickness, bran fraction, rice variety, and environmental conditions during the growing season. The objectives of this study were to quantify the amount of rice bran removed at pre-selected milling times and to correlate the amount of rice bran removed at each milling time with the concentration of vitamin E, gamma-oryzanol, rice bran saccharide, and protein obtained. The ultimate goal of this research is to show that rice bran fractionation is a useful method to obtain targeted, nutrient-rich bran samples for value-added processing. Two long grain rice cultivars, Cheniere and Cypress, were milled at discrete times between 3 and 40 seconds using a McGill mill to obtain bran samples for analysis. Results showed that the highest oryzanol and protein concentrations were found in the outer portion of the rice bran layer, while the highest rice bran saccharide concentration was found in the inner portion of the bran layer. Vitamin E concentration showed no significant difference across the bran layer within a variety, though the highest magnitude of concentration occurs within the first 10 seconds of milling for both varieties. To extract the higher concentration of oryzanol and protein only the outer portion of the bran layer requires processing, while to extract the higher concentration of rice bran saccharide, only the inner portion of the bran layer requires processing. Rice bran fractionation allows for the selective use of portions of the bran layer and is advantageous for two reasons: (1) bran fractions contain higher concentrations of components of interest with respect to the overall bran layer average, and (2) less bran needs to be processed to obtain components of interest.  相似文献   

10.
A thiamine-binding protein was purified from rice germ (Oryza sativa L.) by extraction, salting-out with ammonium sulfate, and column chromatography. From the results of molecular mass, Kd and Bmax values for thiamine-binding, binding specificity for thiamine phosphates and analog, the protein was suggested to be identical to the thiamine-binding protein in rice bran. The thiamine-binding protein w as more efficiently purified from rice germ than from rice bran. The protein was rich in glutamic acid (and/or glutamine) and glycine. The protein did not show immunological similarity to thiamine-binding proteins in buckwheat and sesame seeds. However proteins similar to the thiamine-binding protein from rice germ existed in gramineous seeds. They were suggested to have thiamine-binding activity and to be of the same molecular mass as the thiamine-binding protein.  相似文献   

11.
The stability of cellulolytic and hemicellulolytic enzymes from Macrophomina phaseolina improved on immobilization and was 1.5 to 2-fold more active against pre-treated wheat bran, rice bran or jute powder. The hydrolysis efficiency of the catalyst increased with a decrease in its particle size. About 80% (w/v) of the sugar obtained from wheat bran was assimilated by Saccharomyces sp., whereas the corresponding values for rice bran and jute powder were about 70 and 50% (w/v), respectively.  相似文献   

12.
The cooked odor concentrate of boiled Antarctic krills was obtained by simultaneous distillation and extraction, in a modified Likens and Nickerson’s apparatus. The sulfur containing fraction was successively separated with preparative gas chromatography. Organoleptically, this fraction seemed to play a significant role in the characteristic odor of cooked krills. The fraction was analyzed by a gas Chromatograph equipped with FPD and FTD, and by GC-MS. Seven sulfur containing compounds and four containing both sulfur and nitrogen compounds were newly identified in the cooked odor of Antarctic krills. These compounds seem to be important contributors to the odor of cooked krills.  相似文献   

13.
During scaleup of Streptomyces avermitilis batch culture based on similarity of geometry, aeration and mixing conditions, the production of avermectins was proportional to the intensity of fermentation odor represented by geosmin. The active stimulatory role of odor component on antibiotic production was detected after addition of volatile compounds separated from the fermentation liquor by steam distillation.  相似文献   

14.
Thirty four samples of rice bran, of which 9 were from raw (untreated) rice (RR) and 25 from parboiled rice (PbR) were collected from commercial rice mills in and around Madras and analysed for storage mycoflora and mycotoxins. Fungi of the Aspergillus flavus group were present in 29 of the 34 samples (8 from RR and 21 from PbR) in quantities ranging from <1–432 thousand propagules/g, though not always as the dominant mycoflora. Fungal numbers were usually higher in RR than in PbR samples.Five of the 9 RR samples and 6 of the 25 PbR samples were positive for aflatoxins. Among 29 isolates of A. flavus obtained from the bran samples, 16 isolates –6 from RR bran and 10 from PbR bran — were found to be toxigenic in vitro. Some isolates of A. candidus also seemed to produce aflatoxin and other fluorescent substances.  相似文献   

15.
B. B. Jana  G. P. Pal 《Hydrobiologia》1984,118(2):205-212
Life history parameters of Diaphanosoma excisum (SARS) were derived from culture tube experiments with media comprising mohua oil cake, mustard oil cake, cow dung and rice bran. Body length, longevity, fecundity and progeny production were highest in rice bran medium. First reproduction time (A) in different media ranged from 2 to 6 days, while the reproduction peak (T) varied from 4 to 13 days. The total offspring per female (S) was directly dependent upon the mean number of eggs per female per life span. The intrinsic (r) and finite rate (er) of natural increase were larger for rice bran than for other media.  相似文献   

16.
The neutral fraction of nonstarch lipids in developing brown rice (Oryza sativa L., cv IR42) was accumulated up to 16 days after flowering (DAF), but phospholipids and glycolipids increased only up to 8 DAF. Fatty acids accumulated in nonstarch lipids until 12 DAF. However, the proportion of linolenic acid in the lipid fraction decreased and that of oleic acid increased during this period. Accumulation of fat-by-hydrolysis in the brown rice occurred until 20 DAF and followed closely that of starch. The proportion of linolenic acid decreased and that of linoleic acid increased until 16 DAF. The fatty acid composition of fat-by-hydrolysis and starch lipids were identical and fat-by-hydrolysis accounted for 48% by weight of starch lipids. Nonstarch lipids were mainly composed of triglycerides and were located in the bran and embryo of mature brown rice. Starch lipids were mainly composed of lysophosphatidyl choline, free fatty acids and lysophosphatidyl ethanolamine, and were located in the endosperm.  相似文献   

17.
The compositions of the volatile and polar fractions from two coexisting Black Sea invertebrates, the mussel Mytilus galloprovincialis and the beadlet anemone Actinia equina, were established. The main metabolites in the volatile fraction from the investigated animals appeared to be methyl esters of fatty acids and fatty aldehydes. In the polar fraction from both animals low concentrations of free acids and nitrogen-containing compounds were obtained. Free carbohydrates were in much higher concentrations in M. galloprovincialis than in A. equina. Some sterols, probably as polar conjugates, were identified mainly in A. equina. Significant changes among all compounds appeared after treatment of both invertebrates with two different concentrations of cobalt ions. The variety of changes in each invertebrate could be due to their different evolutionary status. The effect of cobalt ions was often stronger at medium cobalt-ion concentrations.  相似文献   

18.
Natto, a traditional Japanese food product, was prepared from cooked soybeans by fermentation and its odor concentrate was obtained with a simultaneous distillation and extraction system. It was compared to those obtained from soybeans cooked for 0 ~ 3, 3 ~ 5.5 and 5.5 ~ 8 hr, respectively, by gas chromatography and gas chromatography-mass spectrometry. In the odor concentrates of the cooked soybeans, hexanal, (E)-2-hexenal and hexanol contributing to the green and grassy odor of soybeans disappeared or decreased while the cooking was in progress. 2-Pentylfuran and 1-octen-3-ol contributing to the beany odor remained even if the soybeans were cooked for 8 hr and were fermented into Natto. In the odor concentrate of Natto, pyrazines and sulfur containing compounds were important contributors to the characteristic odor of Natto. As the beany odor was not detected for Natto, it was concluded that the pyrazines and sulfur containing compounds cause the characteristic odor of Natto and mask the beany odor.  相似文献   

19.
【目的】本研究旨在通过显微观察和16SrRNA基因高通量测序技术来探究饲喂生物发酵稻秸对湖羊肠道上皮形态及微生物区系的影响。【方法】试验选择70日龄、体重相近(25.15±0.47)kg的湖羊公羔21只,根据饲粮中粗饲料的组成随机分为3组:稻秸组、生物发酵稻秸组和苜蓿干草组,饲粮精粗比为6:4,试验持续7周,其中适应期3周,正试期4周,结束后屠宰取样,采集瘤胃、空肠和结肠上皮组织进行观察测量,收集对应肠段内容物用于微生物区系和代谢产物测定。【结果】与稻秸组相比,饲喂生物发酵稻秸显著提高湖羊瘤胃中纤维杆菌(Fibrobacteres)的相对丰度和挥发性脂肪酸(volatile fatty acids, VFA)的含量,促进瘤胃上皮的发育;显著提高湖羊空肠中厚壁菌门(Firmicutes)和疣微菌门(Verrucomicrobia)的相对丰度,改变空肠微生物菌群结构,促进空肠上皮组织的发育;改变湖羊结肠微生物菌群结构。【结论】饲喂生物发酵稻秸有利于湖羊肠道上皮的发育,并增加消化道内的微生物多样性。  相似文献   

20.
This study investigated the production of value-added protein and amino acids from deoiled rice bran by hydrolysis in subcritical water (SW) in the temperature range between 100 and 220 degrees C for 0-30 min. The results suggested that SW could effectively be used to hydrolyze deoiled rice bran to produce useful protein and amino acids. The amount of protein and amino acids produced are higher than those obtained by conventional alkali hydrolysis. The yields generally increased with increased temperature and hydrolysis time. However, thermal degradation of the product was observed when hydrolysis was carried out at higher temperature for extended period of time. The highest yield of protein and amino acids were 219 +/- 26 and 8.0 +/- 1.6 mg/g of dry bran, and were obtained at 200 degrees C at hydrolysis time of 30 min. Moreover, the product obtained at 200 degrees C after 30 min of hydrolysis exhibited high antioxidant activity and was shown to be suitable for use as culture medium for yeast growth.  相似文献   

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