Virginia Polytechnic Institute and State University

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VA Tech's Department of Food Science and Technology

The VA Tech Food Science and Technology Department is the only Food Science Department in Virginia . It is currently ranks #6 nationally for seniors advancing to graduate school. This puts Tech's department ahead of UC Davis, Rutgers and Texas A & M, among others.

The number of undergraduate Food Science majors has increased 111% since 2004, and 100% of departmental graduates are placed either in the food industry or graduate school. With regard to graduate enrollment, Masters student numbers have increased by 76% and PhD students have increased by 61% in the last two years.

The department is developing and offering new undergraduate and graduate courses such as Functional Foods, Nutraceutical Chemistry and Epidemiology of Food- and Water-borne Disease. The College of Ag and Life Sciences is offering a Food Safety option and a Health Product Risk Management option as part of its on-line Masters degree program.

It is evident that VA Tech's Food Science and Technology department prepares students with comprehensive knowledge, critical thinking skills, and communication and leadership skills needed for success in the food industry, food regulatory, graduate school or professional school.

HOT TOPICS AND CURRENT ISSUES

Gouda 's 800-year-old secret could benefit flavour for all dairy

German scientists have reportedly cracked the secret of Gouda 's complex, long-lasting flavor, and this could lead to developing more flavorful cheeses and other dairy products.

German scientists reported in the Journal of Agricultural and Food Chemistry that six gamma-glutamyl peptides appear to be primarily responsible for the ‘kokumi sensation' for which Gouda cheese is known.

“As these gamma-glutamyl peptides might have important implications also to the taste profile of other dairy products, studies on the biogeneration of these kokumi peptides during cheese ripening are currently in progress,” wrote the researchers, led by Thomas Hofmann from the Technical University of Munich.

Gouda was first perfected by farmers in the village of Gouda in Holland about 800 years ago. According to background information in the journal, although many studies over the last three decades have attempted to elucidate the compounds responsible for the complex, long-lasting characteristic taste of the popular cheese, known as the “kokumi sensation”, the answers have eluded researchers until now.

TU Munich's Hofmann and Andreas Dunkel, in collaboration with Simone Toelstede from the University of Münster, used molecular sensory science to show that a 44-week-matured Gouda cheese had a more pronounced ‘mouthfulness' and long-lasting taste complexity than a four week old Gouda.

Further analysis using a combination of high performance liquid chromatography, mass spectroscopy, and gel permeation chromatography (GPC) enabled the identification of two classes of protein, 8 alpha-l-glutamyl and 10 gamma-l-glutamyl dipeptides as potential kokumi-enhancing molecules.

However, only the gamma-l-glutamyl dipeptides were found to “impart an enhanced kokumi sensation to the matured cheese, whereas none of the alpha-glutamyl peptides were found to be active”, said the researchers.

Among these peptides, the key kokumi molecules were proposed to be gamma-Glu-Glu, gamma-Glu-Gly, gamma-Glu-Gln, gamma-Glu-Met, gamma-Glu-Leu, and gamma-Glu-His.

This knowledge could be used to enhance the flavor of dairy products by technological means, said the researchers.

Edible Film May Kill Bacteria in Refrigerated Foods

A new study in the journal, Food Microbiology and Safety, claims that edible films incorporated with lactoperoxidase (LPS) have excellent potential for bacterial inhibition when used for refrigerated foods as well as meat, poultry and seafood .

Antimicrobial edible films and coatings have received attention since they have a good potential to delay microbial spoilage of food and to reduce the risk of surface contamination of food by microorganisms.

According to the researchers, incorporation of biopreservatives (especially bacteriocins and antimicrobial enzymes) and plant extracts into edible films have gained significant interest in the food industry due to their greater acceptability by the increasing number of consumers who seek ‘natural' products.

The authors of the study said that the enzyme, LPS, which is often used to improve the microbial quality of milk and cheese, has a broad antimicrobial spectrum, and they added that the concept of using the enzyme in antimicrobial packaging is quite novel.

Researchers stated that the films exhibit good stability. LPS binds and immobilizes effectively onto films following cross-linking, and it shows appropriate stability and activity at a broad temperature and pH range.

In this research project, the antimicrobial activity of LPS incorporated into alginate films and its components was tested on different bacteria including E. coli, Listeria innocua , and Pseudomonas fluorescens in the presence of different concentrations of H2O2 (0.2, 0.4, and 0.8 millimoles (mM) and KSCN (1, 2, and 4 mM), explained the scientists.

The specific objectives of this research, they said, were to determine the effective concentrations of LPS components against the test bacteria.

The results of the study determined that the antimicrobial activity of the LPS system on target bacteria changed according to the concentrations of KSCN and H2O2.

The scientists said that the results indicated that the growth of all tested bacteria was prevented for a six hour period through application of the LPS system in the presence of 0.4 or 0.8mM H2O2 and 4mM KSCN.

They added that growth of pathogens L. innocua and P. fluorescens was inhibited during a 24 hour incubation period in the presence of 0.8mM H2O2 and 4mM KSCN; however E. coli growth could not be restrained for 24 hours under the same conditions.

The researchers maintain that with 0.2 mM H2O2 and 1 to 4 mM KSCN, a considerable inhibitory effect was obtained only on P. fluorescens , with the decreasing order of the resistance of studied bacteria to the LPS system as follows: E. coli, L. innocua, and P. fluorescens.

The authors concluded that the duration of the antimicrobial effect of the developed LPS system would be extended when the alginate films are applied to refrigerated foods.