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Organisms acquire more calories from eating hot food than eating the identical food cold; thus, the widespread use of microwave ovens might have played a small role in the current obesity epidemic, just as the widespread use of refrigerators might have retarded the historic increase in obesity a century ago. Analysis of the British Cohort Study showed that, net of dietary habit, physical activities, genetic predisposition, and other demographic factors, the ownership of a microwave was associated with an increase of .781 in body mass index (BMI) and 2.1 kg in weight (when the ownership of other kitchen appliances was not associated with increased BMI or weight), and it more than doubled the odds of being overweight. In the United States from 1960 to 2015, the adult overweight, obesity, and extreme obesity rates were very highly correlated (r= .94–.98) with the proportion of households with microwaves, and it was not because both were consequences of increasing wealth. Net of median household income, the proportion of households with microwaves was very strongly (ds > 1.0) associated with adult overweight, obesity, and extreme obesity rates, while median household income was not at all associated with them. Individual data from the United Kingdom and historical data from the United States highlighted the possible role of the widespread use of microwave ovens in the obesity epidemic.

Provides information on the best buy microwave ovens in 1999. Description and features; Prices; Buying tips.

Describes three basic styles or types of microwave ovens.

Presents information and guidelines in purchasing microwave ovens. Common features of microwave ovens.

Reports that today's microwave ovens boast more power for faster cooking and smarter controls for easier operation. Addition of built-in prompts for some models; Inclusion of a child lock with an electronic code; Prices. INSET: The care and feeding of your microwave ovens..

Provides information concerning microwave ovens. Buying considertions; Full-size; Midsize; Compact; Over-the -range; Combo units.

Presents a guide in buying microwave ovens. Features; Models; Prices.

Presents a buyers' guide for microwave ovens. `Consumers Digest' recommendations; Prices; Full-size models; Midsize models; Compact models; Combo units; Over-the-range models.

The article offers information about the galley design and sales specializes in creating food preparation and storage facilities for large yachts and workboats. According to the general manager and director of operations, Fred Lillian, the galley is the heart of the vessel and a comfort zone for passengers and crew. While galley design is often contracted out in commercial naval architecture, Lillian recognizes its importance and prioritizes it in the design process.

The article informs on several historical events. Topics include in 2013, a 7.5magnitude earthquake struck off the coast of Alaska; Apple Inc. introduced the first iPhone in 2007; and In 1992, Roberta Bondar became the first Canadian woman in space. It also mentions the patent for the microwave oven was granted in 1950.

AbstractThe introduction of several Not-Ready-to-Eat (NRTE) products, beginning in 2007, has resulted in several recalls and has caused serious concerns about their safe-cooking in microwave ovens. These products are not fully-thermally processed prior to sale but depend upon the consumer to finish cooking them to the safe minimum temperatures, defined by the USDA, in order to destroy any sources of foodborne illnesses. While microwave ovens are a primary means of this finish-cooking step, they are known to cook foods unevenly in terms of temperature distribution, especially from a frozen state, and this may cause parts of the food to be below the required safe-temperature. Hence there are concerns regarding how reliably microwave ovens can provide the minimum required safe temperatures in order to avoid the possibility of foodborne illnesses. To determine this, temperature profiling tests were preformed upon three frozen NRTE entrées, heating them in eight new brand-name 1100-watt and 1200-watt microwave ovens in order to evaluate how well the minimum temperatures were reached throughout the products. By comparison, these same tests were repeated using three “smart” microwave ovens in which internal computer-control makes them user-independent. In addition, a comparison was also made of the microwave output power claimed by the manufacturers of these ovens to that determined using the IEC procedures.

AbstractDue to the inherent nature of standing wave patterns of microwaves inside a domestic microwave oven cavity and varying dielectric properties of different food components, microwave heating produces non-uniform distribution of energy inside the food. Non-uniform heating is a major food safety concern in not-ready-to-eat (NRTE) microwaveable foods. In this study, we present a method for assessing heating rate and non-uniform heating in domestic microwave ovens. In this study a custom designed container was used to assess heating rate and non-uniform heating of a range of microwave ovens using a hedgehog of 30 T-type thermocouples. The mean and standard deviation of heating rate along the radial distance and sector of the container were measured and analyzed. The effect of the location of rings and sectors was analyzed using ANOVA to identify the best location for placing food on the turntable. The study suggested that the best location to place food in a microwave oven is not at the center but near the edge of the turntable assuming uniform heating is desired. The effect of rated power and cavity size on heating rate and non-uniform heating was also studied for a range of microwave ovens. As the rated power and cavity size increases, heating rate increases while non-uniform heating decreases. Sectors in the container also influenced heating rate (p < 0.0001), even though it did not have clear trend on heating rate. In general, sectors close to the magnetron tend to heat slightly faster than sectors away from the magnetron. However, the variation in heating rate among sectors was only 2 °C/min and considered not practically important. Overall heating performance such as mean heating rate and non-uniform heating did not significantly vary between the two replications that were performed 4 h apart. However, microwave ovens were inconsistent in producing the same heating patterns between the two replications that were performed 4 h apart.

Electromagnetic radiation from microwave ovens in Saudi Arabia was investigated by means of a field measurement survey. The survey was carried out for 106 ovens used in households and restaurants in Riyadh city. Ovens were between 1 month and 14 years old with operating power ranging from 0.5 to 4.4 kW. One oven was found to leak more than the 5 mW cm-2limit specified in the standard. Fifteen other ovens were found to leak 1 mW cm-2or more, with the remaining ovens leaking less than that. Based on the survey result, previous studies and the fast decay of radiated power density with distance from the oven, the conclusion was that user exposure to RF radiation from microwave ovens is much less than the general public exposure limit set by most international standards at 2450 MHz, i.e. 1 mW cm-2, and that a detrimental effect on health is an unlikely result of exposure to radiation from microwave ovens.

Aluminum and zirconia oxides are ceramic materials widely used in the manufacturing of dental products, however, the thermal treatment stages demand high temperatures. Aiming at the reduction of the energy consumption and of the time necessary for the thermal treatments, this work intends to evaluate the influence of the microwave energy over the thermal processes of alumina substrate and of the alumina/zirconia system. The samples were made by slip-casting and then submitted to different thermal treatments. For the microwave oven, we used powers of 1.44 and 1.66 kW and heating times of 10, 15 and 20 minutes. The samples were submitted to the determination of physico-mechanical properties: flexural strength at three points, porosity and Vickers microhardness. Based on the analysis, we conclude that the microwaves energy is promising for the processing of dental ceramic, causing a significant reduction in the firing time.

Several commercially available plastic containers of polycarbonate, polypropylene-copolymer, polypropylene-20% talcum, polypropylene random and styrene-acrylonitrile designed for heating food in microwave ovens were studied. The analytical procedure based on a purge & trap (P&T) GC-MS was optimized. It consisted of heating the materials at 100°C in a P&T system coupled in line with GC-MS equipment. The compounds released from the materials were then identified through their mass spectra. Variables such as the time of purge using helium as the carrier gas in the system, sample temperature, the type of solid trap, the desorption temperature and the time as well as chromatographic separation of all the compounds released from the plastic were optimized. Compounds such as methylbenzene, ethylbenzene, 1-octene, xylene, styrene and 1,4-dichlorobenzene were found in all the containers. Quantitative analysis and potential migrations are reported and discussed.

AbstractMicrowave assisted chemical reaction is increasingly studied in recent years by using the modified domestic microwave oven to heating on chemical reaction in the laboratory scale study. But the problems of temperature distribution non-uniformity and low power efficiency in the heating process are becoming a new obstacle in the application of microwave chemistry. An optimized microwave oven with two sources is proposed in this paper from the view of feeding system to overcome these disadvantages. As water is usually concerned as important solvent and reactant, a beaker of water is used as heating load in this study. By modeling the process of heating water for 180 s, the standard deviation and the average temperature are compared between the domestic microwave oven and the optimized microwave oven with two sources. As a result, the power is utilized more efficiently as a 20.14% increase can be seen by using the optimized microwave oven under the same microwave power and more uniformity is obtained as a 11.23% increase is performed by the use of the optimized microwave oven under the same heating conditions.

The evaluation of the health risk from exposure to electromagnetic radiation during microwave cooking is based on measurements of the radiation emission from the appliances. In standardised measurements radiation leakage data were collected from 130 microwave ovens in domestic use. None of the checked appliances emitted microwave radiation exceeding a power density of 1 mW cm-2at a distance of 5 cm from the surface of the device. On the basis of statistical calculations it can be assumed that 50% of all microwave ovens currently in use emit less than 0.062 mW cm-2. If the statistical model of the measurements is valid for all microwave ovens in use, the probability for a single device to exceed the actual emission standard of 5 mW cm-2may be less than 0.05%. Measurements showed that detrimental health effects are not expected to occur as a result of radiation exposure during microwave cooking.

The cataractogenic effects of the microwave oven on rat eyes were investigated histologically. Twenty-one adult Wistar-Albino rats (2–2.5 months old) were divided into three groups (n = 7): a control group (sham-exposed) and two experimental groups. The experimental rats were confined in special cages and placed next to the closed door of a microwave oven. The first experimental group was given 15 minutes of daily exposure and the second, 30 minutes, for 1 month. Biomicroscopic examination detected no pathological damage to the lens in the experimental rats. Histologically, there was a lens of single-layered epithelium in the control group. In the first experimental group, there was slight pleomorphism in the superficial epithelial cell contours and vacuolizations in the lens fibers; the second experimental group, had pronounced pleomorphism and pyknosis of the nuclei in the superficial epithelium. Some of the superficial epithelial cells had disappeared and were histologically observed as acellular areas. Single-layered epithelium became disorganized and formed multilayered epithelial groups in the superficial epithelium. Vacuolization was more prominent in this group. Personal exposure from microwave ovens is generally minimal because of the rapid decrease in power density with distance. Microwave oven users do not normally stand as close to the oven as the rats in our study were placed; therefore, it is difficult to suggest that microwave ovens always have cataractogenic effects on human eyes.

Two characteristics of microwave ovens that are important to consumers as they select and use microwave ovens are the wattage output (cooking power) and the evenness of distribution of energy within the oven cavity. Several test methods have been proposed to measure each of these characteristics, but there is not agreement in the industry on realistic methods of their measurement. The purpose of this study is to evaluate a variety of methods for determining cooking power and energy distribution. Cooking power was measured using the temperature rise of water loads. The influence of initial load temperature, quantity of water, profile, and location of the load within the cavity (centrally located versus dispersed) was determined. Energy distribution was measured using nonfood loads (a three-dimensional copying paper load and various water loads), a simple food (gelatin), and a complex food (custard). Placement of the load, the profile, and the composition of the load affected the apparent energy distribution. Recommendations for standardized tests resulted from this research.

Increased publicity and articles in many professional journals prompted the Radiological Health Section of the Orange County Health Department to conduct an accelerated survey of radiation leakage from microwave ovens. Ninety-three ovens were surveyed throughout the county. Seven of the residential ovens and 23 of the commercial ovens tested were measured to be leaking above the present voluntary industry maximum standard of 10 mW/cm2. Twenty-eight of the home ovens and 41 of the commercial ovens had some type of mechanical deficiencies. The greatest potential hazard exists for the personnel operating commercial microwave ovens in restaurants and other food service areas-due to the greater “on time” of the oven, the close proximity to the oven while in operation, the excessive wear on the oven due to increased use and the lack of proper cleaning and maintenance of the oven.

How to guide designers to create product for meeting consumers’ sensational expectations effectively is one of the important aims of Kansei Engineering. The difficult is to reveal the relationship between the emotional imagery and product design elements. The SD and JK methods are selected to build the test sample, emotional vocabulary and deconstructing design elements, then the BP neural network is applied to form the quantitative relationship model between the emotional imagery and design elements. That the front panel of computer-based microwave is taken as research object, the validity of the model has been verified.

AbstractReducing the sensitivity of microwave oven heating and cooking performance to load volume, load placement and load properties has been a long-standing challenge for microwave and microwave-convection oven designers. Conventional design problem and solution methods are reviewed to provide greater insight into the challenge and optimum operation of a microwave oven after which a new strategy is introduced. In this methodology, a special load isolating and energy modulating device called a transducer-exciter is used containing an iris, a launch box, a phase, amplitude and frequency modulator and a coupling plate designed to provide spatially distributed coupling to the oven. This system, when applied to a combined microwave-convection oven, gives astounding performance improvements to all kinds of baked and roasted foods including sensitive items such as cakes and pastries, with the only compromise being a reasonable reduction in the maximum available microwave power. Large and small metal utensils can be used in the oven with minimal or no performance penalty on energy uniformity and cooking results. Cooking times are greatly reduced from those in conventional ovens while maintaining excellent cooking performance.

A new microwave tube design, suitable for application in microwave ovens, is described. It is a development of the basic planar magnetron in which the cathode and anode are two annuli and the magnetic field is radial. Potential advantages over existing designs are: higher power density, higher efficiency, easier tuning, the probability of reduced harmonics, and lower manufacturing costs.

The authors conducted an investigation to determine the extent and source of an outbreak of Salmonella typhimurium gastroenteritis that occurred following a community picnic in Juneau, Alaska, in 1992, and to evaluate risk factors for illness. A case-control study among 54 picnic attendees and a retrospective cohort study among 60 members of 17 households who had taken home leftover food from the picnic were conducted. A case was defined as diarrhea with onset 12-72 hours after eating food that had been prepared for the picnic. The case-control study associated illness with eating roast pork from one of two pigs that had been flown in from a Seattle, Washington, restaurant. The roast pork was taken home by persons from at least the 17 households included in the cohort study. The cohort study identified 43 persons who ate roast pork, of whom 21 (49%) became ill. This compared with only one case of illness among 17 cohort members who had not eaten roast pork (relative risk = 8.3, 95% confidence interval 1.2-57.0). Of 30 persons who ate reheated meat, all 10 who used a microwave oven became ill, compared with none of 20 who used a conventional oven or skillet. The Seattle restaurant had prepared the roast pork by first thawing two frozen pigs for several hours at room temperature and then cooking them in a gas-fired flame broiler. One of the pigs was left unrefrigerated for 17-20 hours after cooking. Compared with conventional methods of reheating, microwave ovens had no protective effect in preventing illness. To prevent outbreaks such as this one, care must be taken to assure that food is both properly cooked and handled and properly reheated.

Consumer exposures to microwave ovens have received considerable attention; however, there was only one report found in the literature concerning occupational exposure of oven repairmen. In repair and testing such ovens, the workmen must remove the casings and jump the safety interlocks. The workers are required to place their faces and bodies close to the energized magnetron. The medical evaluation of eight such repairmen is discussed in relation to the potential biologic side effects of such radiation, which include cataracts and thermal damage to the skin and deeper structures. Environmental evaluations revealed microwave levels in excess of 10 mw/cm2, at the repairman's face and body. A simple, effective, and inexpensive control measure, using copper mesh screening, is described. This control reduces the worker's exposure to a level well below 10 mw/cm2 and allows him to continue visually observing for malfunctions in and around the magnetron.

There has been an increase in the use of microwave ovens for cooking foods. Their use results in a considerable reduction in cooking time over conventional ovens. A study was made of 187 commercial use ovens to determine the extent of leakage of microwave radiation. Twenty percent were found to leak 10 or more mw/cm2 within two inches at the perimeter of the closed oven door. There is concern about this leakage, particularly because of the increased use of these ovens in the home. There is a need for an improved door design to minimize leakage. Improved safety interlocks are needed also in some models to assure cut off of microwave radiation while the door is being opened.

Summary:The ring‐opening cationic polymerization of 2‐ethyl‐2‐oxazoline was performed in a single‐mode microwave reactor as the first example of a microwave‐assisted living polymerization. The observed increase in reaction rates by a factor of 350 (6 h → 1 min) in the range from 80 to 190 °C could be attributed solely to a temperature effect as was clearly shown by control experiments and the determined activation energy. Because of the homogenous microwave irradiation, the polymerization could be performed in bulk or with drastically reduced solvent ratios (green chemistry).

The effects of combined conventional and microwave oven baked white layer cake characteristics were studied. Two types of commercially milled wheat flour, white (A) and whole wheat (B), were used. The modified white layer cake making method was used for conducting the cake baking trials. The conventional baking times (8 or 11 min), microwave power (400 or 600 W) and microwave baking time (30, 40, or 50 s) were chosen as baking parameters. Conventional baking was applied to form the cake crust before baking with the microwave oven used to form the crumb of the cakes. The performance of combination baking was compared with the performance of conventional baking. The volume, bake loss, internal factors, and crust color of cakes were evaluated as quality characteristics. The bake losses of cakes using the combination of short oven times and low microwave power for selected microwave times were smaller than the bake losses of the control cakes for both flours. Long oven times and low microwave power increased the specific volume of cakes. Cakes baked from flours A and B exhibited similar internal properties. Oven time significantly affected the crust color of cakes made with flour A. The crust color of cakes made with flour B was similar to the crust color of control cakes. Using a combination of conventional and microwave baking produces cakes with qualities equivalent to the qualities of cakes produced with conventional baking.

Focuses on several microwave ovens. Explanations on the control panels of microwave ovens; Details on the Panasonic NNS980BA; Information on the GE Profile JE1060WB.

The article discusses the safety of using microwave ovens and its impact on the health of the users. Microwaves are a form of electromagnetic radiation which are part of the electromagnetic spectrum including radio waves, infrared and ultraviolet light. There is no danger in cooking food with the use of a microwave; however, dangers with microwave ovens can reduce the nutritional content once it is over-cooked. INSETS: DO MICROWAVE OVENS LEAK RADIATION?;WHICH CONTAINERS ARE SAFE?.