Microwave frozen foods

Bottles for carbonated soft drinks, 60% custom containers for products other than carbonated soft drinks, 30% amorphous (packaging) and crystallized (microwave and oven trays for frozen foods), 10%... 

PET Polyethylene terephthalate Beverage bottles, frozen food, boil-in-bag pouches, microwave food trays... 

The use of microwave ovens has increased the convenience of dehydrated foods to the same level as that of frozen foods. Dehydrated foods can be produced, packaged and distributed at a fraction of the cost of frozen or canned foods. For these reasons dehydrated soup mixes and pasta based mixes are one of the fastest... 

From these equations, it is clear that an increase in temperature reduces the relaxation time. When the dielectric loss factor increases with the increasing temperature, food would experience a phenomenon known as thermal runaway. When frozen food is thawed with higher microwave power, certain area of the food would be overheated while other areas remain much cooler. Hence, it is important to maintain low microwave power for thawing frozen food to have a uniform thawing. 

PET is used for packaging food, distilled spirits, carbonated soft drinks, noncar-bonated beverages, and toiletries. Typical food products include, for example, mustard, peanut butter, spices, edible oil, syrups, and cocktail mixers. Its crystallized form (CPET) is the basic material for microwavable containers for frozen meals. Biaxially oriented PET is used in meat and cheese packaging and as a base for snack food laminations. PET coating on paperboard produces ovenable board for use in applications such as frozen dinners. PET pouches are used for boil-in-bag frozen foods, and for sterilizable pouches for medical applications. 

Most plastics used in dual ovenables are two to six times more expensive than the aluminum containers they replace in frozen food applications. Less expensive plastic containers are made of molded fiber and polyester and paper laminates. However, due to the popularity of the microwave oven, in many cases microwaveable-only containers, instead of dual ovenables, are used. For example, Campbell uses a polypropylene microwaveable-only container for its Soup du Jour, thereby reducing the material costs considerably. 

A heat-tolerant plastic that can be molded into multi-compartment and single frozen food containers can be heated in the microwave or conventional oven. 

Microwave Ovens. A microtrave oven is a common household appliance. It rapidly heats frozen foods, pops popcorn, bakes potatoes, and bods water. Its compact size makes it beneficial when space is at a premium. It is used on commercial airlines for meal preparation and is found in many other locations, including offices. In addition, microwave heating is employed in many industrial processes for drying and curing products. 

Retortable plastics. Retortable plastics packs are directed at two markets competition with tinplate or aluminium cans and glass jars in parts of the shelf-stable foods market where the foods can be reheated in the bowl or tray and replacement of chilled or frozen foods in the ready-to-eat (single serve) mode in a shelf-stable format. The aim is to provide food subjected to a somewhat shorter heat process than with cans, due to the flatter geometry of the packs and provision for microwave reheating for convenience in the home, institution or vending machine. 

When frozen food is bombarded with microwave radiation, the water molecules in the food absorb the energy and begin to rotate more rapidly. As neighboring molecules collide with each other, the rotational energy is converted into translational energy (or heat), and the temperature of the food rises quickly. This process only works when water molecules are present. Plastic items... 

Li, H.C., G.A. Reineccius, Fhotection of artificial blueberry flavor in microwave frozen pancakes by spray drying and secondary fat coating processes, in Encapsulation and Controlled Release of Food Ingredients, S.J. Risch, G.A. Reineccius, Eds., Amer. Chem. Soc., Washington, D.C., 1995, p. 180. 

Microwave heating may be preferable to other ways of cooking unthawed frozen foods because when food is penetrated by the microwaves cooking proceeds uniformly throughout, whereas in other ways of cooking the heat acts mainly on the outside of the food, which may become overcooked, while the interior is undercooked. 

Quick thawing of a frozen food in a microwave oven... 

Microemulsions for Quick Thawing of a Frozen Food in a Microwave Oven... 

Thawing of a frozen food is traditionally done by leaving it at room temperature. Another way to thaw a frozen food is to use microwave energy. However, these methods are relatively slow and lead to nonuniform thawing. 

There is an increasing demand for ready-prepared foods for final re-heating or cooking in microwave ovens. Applications are for retail sale of take-away meals and factory/ office and institution catering. Such foods maybe frozen and will then have a longer storage life, but will require frozen storage. 

Feng, H., Tang, J., Mattinson, D.S., and Fellman, J.K. 1999. Microwave and spouted bed drying of frozen blueberries The effect of drying and pre-treatment methods on physical properties and retention of flavor volatiles. J. Food Process. Preserv. 23, 463-479. 

Microwave food products are rarely as simple as the water and oil systems discussed above and caution must be exercised in predicting the reaction of individual flavor components in complex food systems containing salt, proteins, sugars, starches, and other food ingredients. Liquid products quickly dissipate the microwave energy and result in a more uniform product. Solid food products, multiphase systems, or frozen products develop hot spots during heating which further complicate flavor delivery in these systems. Performance of the flavor in the microwave is dependent not only on the physical/chemical properties of individual flavor components, but more importantly, on the Interaction of these components with complex food systems. 

JOHNS s w, JiCKELLS s M, READ w A and CASTLE L, Studies on functional barriers to migration. 3. Migration of benzophenone and model ink components from cartonboard to food during frozen storage and microwave heating , Packag. Technol. Sci, 2000 13 99-104. 

Freeze drying is a technique for dehydrating substances at low temperatures, thereby avoiding the degradation that may accompany heating. The material to be dried is cooled to a temperature at which all of the water present turns to ice. The frozen substance is then placed in a vacuum chamber and may also be subjected to radiant or microwave heating the ice in the food sublimates, and the vapor is carried off by the vacuum pump. 

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