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Antimicrobial packaging is an important form of active packaging that can release antimicrobial substances for enhancing the quality and safety of food during extended storage. It is in response to consumers demand for preservative-free food as well as more natural, disposable, biodegradable, and recyclable food-packaging materials. The potential of a combination of allyl isothiocyanate and potassium sorbate incorporated into polymers in providing the needed natural antimicrobial protection for bread products is discussed. The role of double extrusion process as a means for obtaining a homogeneous mix of the sorbate into the polymer (polyethylene or ethylenevinyalcohol), is highlighted.  相似文献   

3.
The presence of residues from frequent antibiotic use in animal feed can cause serious health risks by contaminating products meant for human consumption such as meat and milk. The present paper gives an overview of the electrochemical methods developed for the detection of phenicol antibiotic residues (chloramphenicol, thiamphenicol, and florfenicol) in different kinds of foodstuffs. Electrochemical sensors based on different biomolecules and nanomaterials are described. The detection limit of various developed methods with their advantages and disadvantages will be highlighted.  相似文献   

4.
Xylitol is a sugar alcohol that is used as a sweetener for diabetics and also for other purposes (e.g., in chewing gum). Industrially, xylitol is manufactured through a chemical process that has some disadvantages, including a high energy requirement, extensive purification steps, and a high cost of product. The microbial production of xylitol has been examined as an alternative to the chemical process, which on an industrial scale is time-consuming mainly due to sterilization and inoculum development. The enzymatic production of xylitol from lignocellulosics is an attractive and promising alternative to the chemical process, potentially eliminating the major disadvantages of conventional processes. This article reviews the literature on xylitol production processes and identifies ways to further improve xylitol synthesis to compete with the current chemical process.  相似文献   

5.
Chickpea is grain legumes grown mainly in areas with temperate and semiarid climate. It is characterized by a high content of protein, fat, vitamins, fiber, and a lower content of carbohydrates than flour of wheat. Chickpeas may contain antinutritional compounds that can impair utilization of the nutrients by people. Heat treatment is an effective method to increase the amount of protein available for intestinal digestibility. Adding chickpeas to a foodstuff can increase their nutritional value and reduce the acrylamide content. Acrylamide is an antinutritional substance present in foods, such as bread, snacks, and chips. Chickpea flour and protein may be new way to a reduce the content of acrylamide in products of this type. The addition of chickpea flour affects the sensory and textural properties.  相似文献   

6.
Marine lipids have long been documented to be the major source of polyunsaturated fatty acids (PUFAs), especially n-3 fatty acids such as eicosapentaenoic acid (EPA; 20:5 n-3) and docosahexaenoic acid (DHA; 22:6 n-3). Both EPA and DHA have been documented to have significant influence on biochemical and physiological changes in the body. Although these long chain PUFA exert positive influences on human nutrition and health, there are also some controversies pertaining to the functioning of these n-3 PUFAs including the extent of their requirement by the body. As marine lipids have been thoroughly reviewed often, the present review mainly focuses on works related to physiological effects of EPA and DHA.  相似文献   

7.
Contributions of spray drying to food processing applications are increasing as compared to other conventional drying methods. Spray drying has not only contributed in drying of fluids but also has played a vital role in encapsulation and microencapsulation of valuable foods and functional–nutraceutical ingredients. Microencapsulation by spray drying is a cost-effective one-step process as compared to other encapsulation methods. Encapsulation using spray drying is mainly used in the food sector to protect bioactive compounds or functional foods from light, temperature, oxidation, etc. This paper reviews the work done in past years in the functional food and nutraceutical sector using spray drying. The paper focuses on the role of spray drying in vitamins, minerals, flavouring substances, antioxidant compounds and fatty acids encapsulation.  相似文献   

8.
The global citrus industry is continually confronted by new technological challenges to meet the ever-increasing consumer awareness and demand for quality-assured fruit. To face these challenges, recent trend in agribusiness is declining reliance on subjective assessment of quality and increasing adoption of objective, quantitative and non-destructive techniques of quality assessment. Non-destructive instrument-based methods are preferred to destructive techniques because they allow the measurement and analysis of individual fruit, reduce waste and permit repeated measures on the same item over time. A wide range of objective instruments for sensing and measuring the quality attributes of fresh produce have been reported. Among non-destructive quality assessment techniques, near-infrared (NIR) spectroscopy (NIRS) is arguably the most advanced with regard to instrumentation, applications, accessories and chemometric software packages. This paper reviews research progress on NIRS applications in internal and external quality measurement of citrus fruit, including the selection of NIR characteristics for spectra capture, analysis and interpretation. A brief overview on the fundamental theory, history, chemometrics of NIRS including spectral pre-processing methods, model calibration, validation and robustness is included. Finally, future prospects for NIRS-based imaging systems such as multispectral and hyperspectral imaging as well as optical coherence tomography as potential non-destructive techniques for citrus quality assessment are explored.  相似文献   

9.
Osteoarthritis (OA) is a regressive ailment that affects a large population of patients. The most common symptoms of OA in humans are cartilage abnormalities. Hydrogels are excellent candidates for cartilage regeneration and are widely accepted as implants. In the past few decades, numerous types of hydrogels have been synthesized to repair cartilage defects. This study highlights recent advances in hydrogel development for the treatment of cartilage defects. In addition, the detailed progression of tailored nanocomposite hydrogels is summarized, and emphasis has been placed on the mechanical properties, especially the tribological behavior of the developed nanocomposite hydrogels.  相似文献   

10.
Bambara groundnut (Vigna subterraenea (L.) verdc) (BGN) is a legume; its origin have been traced back to Africa, and it is the third important legume; however, it is one of the neglected crops. It is highly nutritious, and has been termed a complete food. Its seed consist of 49%–63.5% carbohydrate, 15%–25% protein, 4.5%–7.4% fat, 5.2%–6.4% fiber, 3.2%–4.4% ash and 2% mineral compared to whole fresh cow milk 88% moisture, 4.8% carbohydrate, 3.2% proteins, 3.4% fat, 0.7% ash, and 0.01% cholesterol. Its chemical composition is comparable to that of soy bean. Furthermore, BGN has been reported to be a potential crop, owing to its nutritional composition, functional properties, antioxidant potential, and a drought resistant crop. Bambara groundnut milk (BGNM) had been rated higher in acceptability than milk from other legumes like soybean and cowpea. Probiotics have been defined as live microorganisms which when administered in adequate amount confer a health benefit on the host. These benefits have been reported to be therapeutic, suppressing the growth and activity in conditions like infectious diarrhea, irritable bowel syndrome, and inflammatory bowel disease. The nutritional profile of BGNM is high enough to sustain the growth of probiotics. BGNs are normally boiled and salted, eaten as a relish or roasted, and eaten as a snack. Hence, BGNM can also be fermented with lactic acid bacteria to make a probiotic beverage that not only increase the economic value of the nutritious legume but also help in addressing malnutrition.  相似文献   

11.
The genus Salmonella is composed of two species, Salmonella enterica and Salmonella bongori. Only S. enterica subsp. enterica is considered of human clinical significance and consists of 1478 serotypes. A large number of virulence genes and virulence-enhancing genes have been described for Salmonella. There are more than 30 Salmonella specific genes that have been used for the polymerase chain reaction to detect and characterize Salmonella. The sensitivity of detection of Salmonella from complex matrices such as food and feces by PCR is invariably enhanced using nonselective or selective enrichment, particularly if followed by immuno-magnetic separation in addition to coupling the PCR with ELISA formats. R-plasmids are considered to be the main factors responsible for the horizontal transfer of antibiotic resistance genes in Salmonella. A sizeable number of primer pairs are available for determining by the PCR the presence of many antibiotic resistance genes in Salmonella isolates that are not necessarily specific for Salmonella. The collective PCR detection of members of the genus Salmonella in foods and environmental samples has been achieved by amplification of invA gene sequences that are highly conserved among all Salmonella serotypes in addition to the amplification of his gene sequences also present throughout the genus Salmonella. Amplification of 16S rDNA sequences have also been found useful for genus specific detection of Salmonella. d-Tartrate (dT+) fermenting strains have been found to result in less severe gastrointestinal infections than d-tartrate-nonfermenting (dT-) strains. Primers have therefore been developed for distinguishing between (dT+) and (dT-) strains. Among the molecular techniques available for strain discrimination of Salmonella isolates, pulsed field gel electrophoresis, random amplified polymporphic DNA analysis, ribotyping, multilocus sequence typing, subtracted finger printing, and enterobacterial repetitive intergeneric consensus typing have been found useful. Multiplex PCR has been found effective for simultaneously detecting Salmonella and other pathogens in foods, particularly with real-time PCR.  相似文献   

12.
There are four species of the genus Shigella: S. dysenteriae, S. flexneri, S. sonneii, and S. boydii. It is extremely difficult if not impossible to utilize the PCR for distinguishing between shigellae and the five diarrheagenic pathotypes of Escherichia coli—enterohemolytic (EHEC), enteropathogenic (EPEC), engteroinvasive (EIEC), enterotoxigenic (ETEC), and enteroaggresive (EAEC)—due to the extremely close genetic relationship between Shigella spp. and E. coli. This problem is magnified by the presence of common virulence plasmids in these two microbial groups with virulence genes of extremely high homology. Although gastrointestinal infections by shigellae and EICC occur most frequently in developing nations, the responsible E. coli strains are indistinguishable from shigellae by PCR. In addition, with the exception of S. boydii, the other three species of Shigella are completely indistinguishable from one another by the PCR. The most fruitful approach to date in attempting to use the PCR for distinguishing the four species of Shigella from one another has been to first use immuno-capture based on somatic O antigenicity immediately prior to the use of the PCR to impart species selectivity to a coupled ELISA-PCR assay system. Most PCR assays involving the detection of shigellae have been designed to detect shigellae plus the E. coli pathotype EIEC as a collective and indistinguishable group of enteroinvasive organisms or to distinguish Shigella from pathogenic members of other pathogenic genera.  相似文献   

13.
《Food chemistry》1998,62(1):73-97
This work reviews the literature on the compositional data of vegetable fats used or proposed as alternatives to cocoa butter in chocolate and confectionery products. Cocoa butter is the only continuous phase in chocolate, thus responsible for the dispersion of all other constituents and for the physical behaviour of chocolate. Unique to cocoa butter is its brittleness at room temperature and its quick and complete melting at body temperature. There were, and are, strong efforts to replace cocoa butter in part for chocolate production for technological and economic reasons. Such cocoa butter alternatives are the so-called cocoa butter equivalents (CBEs), cocoa butter substitutes (CBSs) and cocoa butter replacers (CBRs). These are mostly mixtures of various vegetable fats (often modified) and can consist of palm and palm kernel oil, illipé fat, shea butter, sal fat and kokum butter. In addition, a large variety of other vegetable oils can be used. Their composition according to triglycerides, fatty acids, sterols and other unsaponifiable components is discussed in this report.  相似文献   

14.
Nowadays Pulsed Electric Field (PEF) treatment of food needs to be performed prior to packaging, either hygienic or aseptic packaging is necessary. New techniques for PEF treatment after packaging can be considered when plastic conductive (film) electrodes can be integrated within the package, so that the package and the product can be treated as a whole. This paper describes a newly developed treatment chamber, which can be used to test the ability of any arbitrary plastic packaging film to be used as electrodes for PEF treatment. Tests with a flexible commercially available electrically conductive copolymer film showed that reduction of Lactobacillus plantarum by PEF was possible. This heat sealable film obeys the mechanical properties of a polymer; however it has an electrical conductivity of 0.75 S m? 1 and approximately 2.3% of the surface area is electrically conductive. The maximum obtained inactivation was 2.1 log10 with a specific energy of 17 J ml? 1. The microbial experiments gave a consistent outcome compared with finite element simulations and with models from literature. Further research to reach real pasteurisation levels is needed as well as issues concerning utilisation of these film electrodes.Industrial relevanceStainless steel electrodes, which are widely used as electrode material for Pulsed Electric Field (PEF) treatment systems, have as main disadvantage that they exhibit certain wear. This article showed that polymer composites can be considered as electrode material for newly to be developed PEF treatment concepts. With extensive research on food grade composite films the integration of cheap disposable plastic electrodes in food packages comes within reach.  相似文献   

15.
Tomato (Solanum lycopersicum) is one of the most essential herbaceous plants that have been probed against various life sight related disorders owing to array of phytochemicals. It is important source of vitamin C, potassium, folic acid, and carotenoids, such as lycopene. Carotenoids are the pigments synthesized during fruit ripening and responsible for the final red color of the tomato. Consumption of tomato and tomato-based products contribute to the absorption of carotenoids and lycopenes in human serum. Lycopene is chemically acyclic carotene with 11 conjugated double bonds, normally in transconfiguration while isomerization occur in blood plasma for its better absorption. It has ability for adenosine deaminase inhibition that plays important role in the regression of tumor. Tomato also contain other active compounds, namely, neoxanthin, lutein, α-cryptoxanthin, α-carotene, β-carotene, cyclolycopene, and β-carotene 5, 6-epoxide. These components provide synergistic effect against various threats but still need further attention of the researchers. Both in vitro and in vivo studies have elucidated the potential of tomato against variety of metabolic syndromes. Latest research highlights the relationship between consuming tomato and its products with reduced risk of various maladies like obesity, hyperglycemic and hypercholesterolemic attributes, cardiovascular disorders, and cancer insurgences. Moreover, tomato and its bioactive components hold potential to become effective modules in diet-based regimens; however, integrated research and meta-analysis are still required to enhance meticulousness.  相似文献   

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The viscoelastic parameters storage modulus (G′) and loss modulus (G″) were measured at different temperatures (5 °C, 10 °C, 15 °C, 20 °C, 25 °C, 30 °C, and 40 °C) using oscillatory thermal analysis in order to obtain a viscoelastic model for honey. The model (a 4th grade polynomial equation) ascertains the applicability of the time–temperature superposition principle (TTSP) to the dynamic viscoelastic properties. This model, with a regression coefficient higher than 0.99, is suitable for all honeys irrespective their botanical origin (monofloral, polyfloral, or honeydew). The activation energy (relaxation“ΔH a” and retardation “ΔH b”), and the relaxation modulus fit the model proposed. The relaxation modulus has a 4th grade polynomial equation evolution at all temperatures. The moisture content influences all the rheological parameters.  相似文献   

18.
A pheromone-baited trap was developed to monitor the Indian meal moth in grocery stores and similar areas where visible traps are not desirable. The trap can be used under shelves and against walls. As a shelf mount, the trap is in close proximity to the food packages and may capture emerging insects before they mate. The trap can also be used as a hanging trap similar to the Pherocon II. When used as a shelf or wall mount, it was as effective as the Pherocon II, but when used as a hanging trap significantly fewer insects were captured.  相似文献   

19.
徐州齿轮厂所负责承担的 SF45(65)—700A 型塑料挤出多能复膜机组(简图如下)科研课题,经过一年多的研究和试验,于1984年7月6日由市经委主持在合肥市通过了技术鉴定。  相似文献   

20.
<正> 四溴双酚A双(2,3—二溴丙基)醚系由日本、西德和美国等在七十年代研究开发的溴系阻燃剂。近年来日本帝人化学公司(商品牌号Fire Guard 3100)、美国大湖化学公司(商品牌号PE—68)均有商品出售。现天津市合成材料工业研究所在实验室  相似文献   

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