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1.
Thermal imaging is a technique to convert the invisible radiation pattern of an object into visible images for feature extraction and analysis. Infrared thermal imaging was first developed for military purposes but later gained a wide application in various fields such as aerospace, agriculture, civil engineering, medicine, and veterinary. Infrared thermal imaging technology can be applied in all fields where temperature differences could be used to assist in evaluation, diagnosis, or analysis of a process or product. Potential use of thermal imaging in agriculture and food industry includes predicting water stress in crops, planning irrigation scheduling, disease and pathogen detection in plants, predicting fruit yield, evaluating the maturing of fruits, bruise detection in fruits and vegetables, detection of foreign bodies in food material, and temperature distribution during cooking. This paper reviews the application of thermal imaging in agriculture and food industry and elaborates on the potential of thermal imaging in various agricultural practices. The major advantage of infrared thermal imaging is the non-invasive, non-contact, and non-destructive nature of the technique to determine the temperature distribution of any object or process of interest in a short period of time.  相似文献   

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Modified atmosphere packaging (MAP) technology offers the possibility to retard the respiration rate and extend the shelf life of fresh produce, and is increasingly used globally as value adding in the fresh and fresh-cut food industry. However, the outbreaks of foodborne diseases and emergence of resistant foodborne pathogens in MAP have heightened public interest on the effects of MAP technology on the survival and growth of pathogenic organisms. This paper critically reviews the effects of MAP on the microbiological safety of fresh or fresh-cut produce, including the role of innovative tools such as the use of pressurised inert/noble gases, predictive microbiology and intelligent packaging in the advancement of MAP safety. The integration of Hazard Analysis and Critical Control Points-based programs to ensure fresh food quality and microbial safety in packaging technology is highlighted.  相似文献   

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Nonthermal plasma (NTP) is superior to thermal technologies as a technique that provides a satisfactory microbial safety and maintains reasonable standards in food quality attributes. Currently, the effects of NTP on some food components is regarded as beneficial, such as effects on starch and protein modification. For other food components, such as lipid oxidation, NTP is regarded as an undesirable treatment because it leads to quality deterioration and formation of off-flavor. An overview of the basic principles of NTP and food microstructure in relation to NTP-treated food and the underlying mechanisms are discussed. The review further highlights the latest research on plasma application in food and the related impact on food matrices. Efforts were made to outline the research findings in terms of NTP application on foods with an emphasis on the impacts on the food microstructure and their related qualities. In this review, the industrial capacity of NTP to improve the functional properties of starch, proteins, and lipids as well as provide little or no alteration in food quality compared to other technologies are emphasized. Some oxidative breakdown in relation to starch, proteins, and lipids are discussed and documented in this paper as a review of representative available publications.  相似文献   

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Milk and fruit juices have paramount importance in human diet. Increasing demand of these liquid foods has made them vulnerable to economic adulteration during processing and in supply chain. Adulterants are difficult to detect by consumers and thus necessitating the requirement of rapid, accurate and sensitive detection. The potential adulterants in milk and fruit juices and their limits set by different regulatory bodies have been briefly described in this review. Potential advantages and limitations of various techniques such as physicochemical methods, chromatography, immunoassays, molecular, electrical, spectroscopy with chemometrics, electronic nose, and biosensors have been described. Spectroscopy in combination with chemometrics has shown potential for rapid, precise, and sensitive detection of potential adulterants in these liquid foods.  相似文献   

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Since the discovery of gluten by Beccari in the 18th century, wheat producers, millers, and bakers have tried to find relatively simple methods of prediction of wheat quality, particularly during the breeding stages. Bearing in mind that endosperm proteins play the governing role in determination of wheat quality, this prediction is generally based on these proteins. Early research concentrated on relations among the macrofractions (i.e., gliadin:glutenin ratio, ratio of acetic acid soluble proteins, etc.). Later, the gliadin polypeptides, the genes coding for these polypeptides, and variety identification became the focus of research.

More recent predictions are based on the high-molecular-weight glutenin subunits. Although such predictions are successfully applied in many countries for wheat breeding, the low correlation between predicted and practical quality observed in many cases, and the variability of quality of different wheat varieties, suggests that further studies are needed to improve the reliability of this particular prediction.

In the framework of such studies, more attention should be paid to the synthesis and interactions of gluten-forming polypeptides—particularly with respect to the polymerization process of glutenin subunits; the role of redox-system of kernel in the gluten formation; and the formation of gluten complex, including role of nonprotein constituents; consequently, the wheat kernel should be treated as a biological unit. From the methodological point of view, the uses of new techniques such as immunochemistry, nondestructive evaluation methods, etc., hold promise for improved quality prediction.  相似文献   

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Residues of pesticides in food are influenced by processing such as fermentation. Reviewing the extensive literature showed that in most cases, this step leads to large reductions in original residue levels in the fermented food, with the formation of new pesticide by-products. The behavior of residues in fermentation can be rationalized in terms of the physical-chemical properties of the pesticide and the nature of the process. In addition, the presence of pesticides decrease the growth rate of fermentative microbiota (yeasts and bacterias), which provokes stuck and sluggish fermentations. These changes have in consequence repercussions on several aspects of food sensory quality (physical-chemical properties, polyphenolic content, and aromatic profile) of fermented food. The main aim of this review is to deal with all these topics to propose challenging needs in science-based quality management of pesticides residues in food.  相似文献   

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《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   

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Understanding the influence of processing operations such as drying/dehydration, canning, extrusion, high hydrostatic pressure, pulsed electric field, and ohmic heating on the phytochemicals of fruits, vegetables, and grains is important in retaining the health benefiting properties of these antioxidative compounds in processed food products. Most of the previous investigations in the literature on the antioxidants of fruits, vegetables, and grains have shown that food-processing operations reduced the antioxidants of the processed foods, which is also the usual consumer perception. However, in the last decade some articles in the literature reported that the evaluation of nutritional quality of processed fruits and vegetables not only depend on the quantity of vitamin C but should include analyses of other antioxidant phytochemicals and antioxidant activity. Thermal processing increased the total antioxidant activity of tomato and sweet corn. Most importantly, analysis also depends on the condition, type, and mechanism of antioxidant assays used. This review aims to provide concise information on the influence of various thermal and nonthermal food-processing operations on the stability and kinetics of health beneficial phenolic antioxidants of fruits, vegetables, and grains.  相似文献   

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The present review is based mainly on papers published between 2000 and 2011 and gives information about the properties of the carotenoid lycopene in chemical and biological systems and its possible role in preventing cardiovascular diseases (CVD). The main aim of this report is to highlight its role as an antioxidant, also reported are bioactive properties that may influence the development of foam cells and protection against endothelial cell damage. The paper will also examine recent observations that lycopene may improve blood flow and reduce inflammatory responses. Lycopene possesses antioxidant properties in vitro, and some epidemiological studies have reported protective effects against the progression of CVD. The oxidation of human low density lipoproteins (LDL) is a fundamental mechanism in the initiation of atherosclerosis. A beneficial role of lycopene as antioxidant in the prevention of CVD is suggested but the data are still controversial. Lycopene is believed to be the most potent carotenoid antioxidant in vitro. Tissue culture experiments and animal studies support potential cardioprotective effects for lycopene and other carotenoids in the blood. Most studies showed beneficial effects of lycopene to individuals who are antioxidant-deficient like elderly patients, or humans exposed to higher levels of oxidative stress like smokers, diabetics, hemodialysis patients and acute myocardial infarction patients. By defining the right population and combining antioxidant potentials of lycopene with vitamins and other bioactive plant compounds, the beneficial role of lycopene in CVD can be clarified in future studies.  相似文献   

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Over the past century, advancements within the mainstream dairy foods processing industry have acted in complement with other dairy-affiliated industries to produce a human food that has few rivals with regard to safety, nutrition, and sustainability. These advancements, such as milk pasteurization, may appear commonplace in the context of a modern dairy processing plant, but some consideration of how these advancements came into being serve as a basis for considering what advancements will come to bear on the next century of processing advancements. In the year 1917, depending on where one resided, most milk was presented to the consumer through privately owned dairy animals, small local or regional dairy farms, or small urban commercial dairies with minimal, or at best nascent, processing capabilities. In 1917, much of the retail milk in the United States was packaged and sold in returnable quart-sized clear glass bottles fitted with caps of various design and composition. Some reports suggest that the cost of that quart of milk was approximately 9 cents—an estimated $2.00 in 2017 US dollars. Comparing that 1917 quart of milk to a quart of milk in 2017 suggests several differences in microbiological, compositional, and nutritional value as well as flavor characteristics. Although a more comprehensive timeline of significant processing advancements is noted in the AppendixTable A1 to this paper, we have selected 3 advancements to highlight; namely, the development of milk pasteurization, cleaning and sanitizing technologies, and sanitary specifications for processing equipment. Finally, we provide some insights into the future of milk processing and suggest areas where technological advancements may need continued or strengthened attention and development as a means of securing milk as a food of high safety and value for the next century to come.  相似文献   

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《Food chemistry》1998,62(1):99-108
This work reviews the literature on analytical methods suitable for the detection, identification and determination of foreign fats in cocoa butter and chocolate. Most methods are based on chromatography, analysing either the fatty acids, triglyceride or the fractions of the unsaponifiables (sterols, triterpenes, etc.). None of the methods reviewed here allows the unequivocal quantification, or just the detection, of foreign fats in chocolate without any exemption for the kind of foreign fat added. The type of foreign fats which are not detectable depends strongly on the analytical techniques applied. It is proposed to combine a number of techniques with a chemometric approach to develop unique patterns allowing the unequivocal detection and quantification of foreign fats, without having prior knowledge regarding the kind of fat added. This approach is based on the use of a complex pattern of the constituents of cocoa butter and any deviation from this pattern is attributed to the existence of foreign fat.  相似文献   

15.
In the early 1900s, breed society herdbooks had been established and milk-recording programs were in their infancy. Farmers wanted to improve the productivity of their cattle, but the foundations of population genetics, quantitative genetics, and animal breeding had not been laid. Early animal breeders struggled to identify genetically superior families using performance records that were influenced by local environmental conditions and herd-specific management practices. Daughter–dam comparisons were used for more than 30 yr and, although genetic progress was minimal, the attention given to performance recording, genetic theory, and statistical methods paid off in future years. Contemporary (herdmate) comparison methods allowed more accurate accounting for environmental factors and genetic progress began to accelerate when these methods were coupled with artificial insemination and progeny testing. Advances in computing facilitated the implementation of mixed linear models that used pedigree and performance data optimally and enabled accurate selection decisions. Sequencing of the bovine genome led to a revolution in dairy cattle breeding, and the pace of scientific discovery and genetic progress accelerated rapidly. Pedigree-based models have given way to whole-genome prediction, and Bayesian regression models and machine learning algorithms have joined mixed linear models in the toolbox of modern animal breeders. Future developments will likely include elucidation of the mechanisms of genetic inheritance and epigenetic modification in key biological pathways, and genomic data will be used with data from on-farm sensors to facilitate precision management on modern dairy farms.  相似文献   

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The use of ultrasounds has recently gained significant interest in the food industry mainly due to the new trends of consumers toward functional foods. Offering several advantages, this form of energy can be applied for the improvement of qualitative characteristics of high-quality foods as well as for assuring safety of a vast variety of foodstuffs, and at the same time minimizing any negative effects of the sensory characteristics of foods. Furthermore, the non-destructive nature of this technology offers several opportunities for the compositional analysis of foods. However, further research is required for the improvement of related techniques and the reduction of application costs in order to render this technology efficient for industrial use. This review paper covers the main applications of ultrasounds as well as several advantages of the use of the technology in combination with conventional techniques. The effects of ultrasounds on the characteristics, microbial safety, and quality of several foods are also detailed  相似文献   

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