World Library  
Flag as Inappropriate
Email this Article

Susceptor

Article Id: WHEBN0006079682
Reproduction Date:

Title: Susceptor  
Author: World Heritage Encyclopedia
Language: English
Subject: Active packaging, Microwave oven, Microwave popcorn, Electromechanical engineering, Orbital stretch wrapping
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Susceptor

Susceptors may be added to "crisping sleeves" in convenience foods such as Hot Pockets

A susceptor is a material used for its ability to absorb electromagnetic energy and convert it to heat (which is sometimes designed to be re-emitted as infrared thermal radiation). This energy is typically radiofrequency or microwave radiation used in industrial heating processes, and also occasionally in microwave cooking. The name is derived from susceptance, an electrical property of materials that measures their tendency to convert electromagnetic energy to heat.[1]

Operation

In microwave cooking, susceptors are built into paper packaging of certain foods, where they absorb microwaves which penetrate the packaging. This process raises the susceptor patch temperature to levels where it may then heat food by conduction or by infrared radiation.

  • Conduction heating occurs with good thermal contact between susceptor and food. Because of the lower temperatures, there is less browning, but more than if there were no susceptor at all.
  • If there is an air gap (or at least, poor thermal contact) between the susceptor and food, the susceptor will heat to much higher temperature (due to its smaller effective heat capacity when in poor contact with food), and at these higher temperatures, will radiate strongly in the infrared. This infrared radiation then shines onto the food below or next to the susceptor, causing a "broiling" type effect (high skin heating), due to lower ability of infrared to penetrate foods, vs. microwave ovens. Conversion of some microwave to infrared is particularly useful for goods which require a large amount of crust-browning from infrared, such as frozen pies.

Design and use

Susceptors are usually made of metallised film, ceramics or metals (such as aluminium flakes).

The susceptor (which may be located on examination from its gray or blue-gray color, which is different from paper) is the reason products meant to be browned via susceptor-generated thermal radiation carry instructions to microwave the food while still inside its packaging.

Susceptors meant to heat goods by direct conduction in places where less browning will occur may be seen in the gray lining of packaging directly holding food and in good contact with it. A typical example of the latter is the paper susceptor-lined dish directly holding a microwaveable pot pie or casserole.

Susceptors built into packaging create high temperatures in a microwave oven. This is useful for crisping and browning foods, as well as concentrating heat on the oil in a microwave popcorn bag (which is solid at room temperature) in order to melt it rapidly.

Among the first microwave susceptors marketed were those from the mid-1980s in a product called McCain Micro Chips, which demonstrated a susceptor sheet which cooked French fries in a microwave oven. These are currently used in several types of packaging for heating and cooking products in microwave ovens. Care in package design and use is needed for proper food safety.[2]

A "crisping sleeve" is a device made of paperboard and affixed with a susceptor used both as a rigid container to support the food items within and to focus heat on the foodstuff.[3] They are generally intended for a single use.[4] Hot Pockets are a form of the crisping sleeve, while the the actual cuisine is a a stuffed bread type of food

References

  1. ^
  2. ^
  3. ^ US patent 4775771, Thomas D. Pawlowski et al, "Sleeve for crisping and browning of foods in a microwave oven and package and method utilizing same", published October 4, 1988, issued October 4, 1988 
  4. ^

Further reading

  • Yam, K. L., "Encyclopedia of Packaging Technology", John Wiley & Sons, 2009, ISBN 978-0-470-08704-6

External links

  • "Susceptor heating" on commercial website
  • Casting bronze using a domestic microwave oven
  • Susceptor heating film on fast food package with carbon-based coatings
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.