Printer Friendly

Replace thermal sterilization with a combination of selected hurdles.

Consumer demands for high-quality foods are leading to significant modifications in processing technologies. Applying nonthermal treatments and a combination of different hurdle technologies is one way to address these demands.

Minimal or less severe thermal treatments enable foods to better retain heat-sensitive components. These types of treatments also reduce energy consumption. Scientists at Agriculture Canada offer the results of experimental tests using a combination of four selected hurdles: acidification using glucono-delta-lactone (GDL); nisin; irradiation; and thermal pasteurization. The investigators applied these treatments to two foods: chicken broth (bouillon) and Alfredo milk-based pasta sauce.

To verify their research, the scientists used sensory evaluation, accelerated shelf life testing at 35 C and energy consumption as the main evaluation criteria. Their results suggest that single sterilization treatments--the use of individual hurdles--require very high treatment levels, such as strong acidification to pH less than 3.5, high doses of nisin greater than 2 kIU per g, high doses of irradiation greater than 10 kGy and high temperatures of more than 121C.
 In tests, 30 untrained sensory panelists rejected products that were
 highly acidified and which had received high doses of irradiation.
 The relatively high cost of nisin reduced the practical application of
 this treatment to low concentrations.

To overcome these obstacles, the researchers tested several combinations of GDL and nisin at low concentrations. They used low doses of irradiation and pasteurization instead of thermal sterilization. They found the best treatments for both foods to be a combination of: acidification to pH 5.5; a concentration of nisin at 1000 IU per g: irradiation to 2 kGy: and pasteurization at 85 C. By using this approach, about 30% energy savings can be achieved, compared with traditional thermal treatments, while still maintaining the microbial safety of the product.

Further information. Michele Marcotte, Agriculture Canada, Food R and D Center, 3600 Casavant Blvd. West, Saint-Hyacinthe, Quebec Canada J2S 8E3; phone: 450-768-3295; fax: 450-773-2888; email:
COPYRIGHT 2007 Food Technology Intelligence, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2007, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Publication:Microbial Update International
Date:Feb 1, 2007
Previous Article:Cool-water wash for eggs can inhibit microbial contamination.
Next Article:Additional thermal processing can reduce, eliminate surface pathogens.

Related Articles
Flame retardants update: phosphorus expands its niche.
Improve the convenience of prepared meat, cereal, vegetable foods.
High-pressure-process low-acid foods.
Anticipate first filing for low-acid high-pressure processed food.
Child disability and mothers' tubal sterilization.
Glass/polyphenylsulfone to replace aluminum.
COC alloy makes medical packs steam-sterilizable.
Pre Classic loses some top athletes.
Thermoforming PPS: new resin choice adds high-performance opportunity: for parts needing high heat and chemical resistance, thermoformers get a new...
Lysozyme- and nisin-containing films control bacteria on salmon.

Terms of use | Privacy policy | Copyright © 2021 Farlex, Inc. | Feedback | For webmasters