Nagendra Shah Discusses Probiotics and Functional Foods
Interview from the Special Topic of Probiotics: July 2010
Our Special Topics analysis of
probiotics research over the past decade shows that the work of
Professor Nagendra Shah ranks at #5 by total number of papers,
based on 56 papers cited a total of 724 times.
Prof. Shah's work also ranks among the top 1% in the field of Agricultural Sciences in Essential Science IndicatorsSM from Thomson Reuters for the period of January 1, 2000 to February 28, 2010.
Shah is Professor of Food Science and Technology at the School of Biomedical and Health Sciences of Victoria University in Melbourne, Australia.
Would you tell us a bit about your educational
background and research experiences?
I obtained my Bachelors degree from Rajendra Agricultural University, India, a Masters degree in Dairy Science from South Dakota State University, USA, and a Ph.D. in Food Science and Technology from the University of Alberta, Canada.
In dairy science, I have studied the functional properties of milk, fermented dairy products, low-fat mozzarella cheese, probiotic cheddar cheese, ACE-I inhibitory peptides, EPS producing starter cultures.
In microbiology, I have examined the physiology and health properties of Lactobacillus acidophilus, Bifidobacterium spp., and Lactobacillus casei; the proteolytic activities of bacteria, bacteriocin, probiotics, and prebiotics; and enzymic biotransformation of soy isoflavones.
"...cheese remains a relatively new product in which probiotics are being incorporated."
In terms of research output, I have co-authored a book; edited, as Principal Guest Editor, a special issue of International Dairy Journal (November 2007); I was co-editor of a book on dairy products and quality control (with Dr. RC Chandan, and A Kilara); I have written 162 refereed journal papers, 18 book chapters, 16 full papers in conference proceedings, 141 conference abstracts, 56 invited and keynote presentations, and 66 poster presentations.
I have given 29 invited lectures, and I have overseen 24 graduate student completions (19 Ph.D. completions; 5 M.Sc. completions) and 15 Honours completions.
Most recently, I have co-edited, as a principal editor, a book on probiotics and prebiotics that is currently in press and will appear in a couple of months from Nova Sciences.
What first drew your interest to
probiotics?
When I moved to Australia some 20 years ago, I wanted to start my research program in a niche area, and not many researchers were working on probiotics. At that time, Choice magazine had published an article on probiotics showing that the probiotics in probiotic yogurts on the market did not survive through to the claimed shelf life and that there were only a few cells in the products on the market.
This was the beginning of my interest in probiotics. Although a part of my Ph.D. work was on probiotics, it was not until I started at Victoria University that I developed my research career in probiotics. I kept getting research funds, and that kept me going.
The majority of your highly cited papers in our
analysis deal with probiotics as they relate to dairy products. What is
it about dairy products that make them so attractive for probiotic
experiments and products?
"Yogurt is a very popular product for the incorporation of probiotics."
Dairy foods are universally accepted and they provide a good environment for probiotics' growth. Most of these probiotics are classified as lactic-acid-producing bacteria as they produce lactic acid from lactose and are used to growing in dairy products, in particular yogurt. Yogurt is a very popular product for the incorporation of probiotics.
Most of the probiotic-containing products
consumers see on the shelves today are yogurts, but in 2006 you and your
coauthors published a paper in the International Dairy Journal
about a probiotic Cheddar cheese. How did this product come about, and
how does it compare with probiotic yogurts?
There has been some work on probiotic cheeses, but cheese remains a relatively new product in which probiotics are being incorporated. Enumeration of probiotics in the presence of non-starter lactic acid bacteria (NSLAB), long ripening time, presence of salt, and low water activity are some of the issues that needed some attention before probiotic cheese could used as a probiotic carrier.
Late last year you came out with a paper in
theInternational Journal of Food Science and Technology about
the antimicrobial effects of probiotic bacteria ("Antimicrobial effects
of probiotic bacteria against selected species of yeasts and moulds in
cheese-based dips," 44[10]: 1916-26, October 2009). Would you talk a bit
about this paper and its implications?
Dips are another emerging area of interest in which probiotics are being incorporated. Being a neutral product, it makes it very attractive medium for incorporation of probiotics. Most probiotics will not grow in such an environment; hence these products rely on antimicrobial substances produced by probiotic bacteria.
Dips have a limited shelf life, due to limitation in heat treatment. Thus any antimicrobial substance produced by probiotics could enhance their shelf life. This was the intention of our work.
Where do you see probiotics going in the next
decade?
There are a number of probiotic bacteria on the market without much
efficacy data. The next decade will see a lot of work on efficacy and
substantiation of their health effects.
Professor Nagendra P. Shah
Professor of Food Science and Technology
School of Biomedical and Health Sciences
Faculty of Health Engineering and Science
Victoria University
Melbourne, Victoria, Australia
NAGENDRA P. SHAH'S CURRENT MOST-CITED PAPER IN ESSENTIAL SCIENCE INDICATORS:
Shah NP, "Probiotic bacteria: Selective enumeration and survival in dairy foods," J. Dairy Sci. 83(4): 894-907, April 2000 with 182 cites. Source: Essential Science IndicatorsSM from Clarivate.
KEYWORDS: PROBIOTICS, FUNCTIONAL PROPERTIES, DAIRY PRODUCTS, ACE-I INHIBITORY PEPTIDES, EPS-PRODUCING STARTER CULTURES, LACTOBACILLUS ACIDOPHILUS, LACTOBACILLUS CASEI, BIFIDOBACTERIUM SPP, PROTEOLYTIC ACTIVITY, BACTERIOCIN, PREBIOTICS, ENZYMATIC BIOTRANSFORMATION, SOY ISOFLAVONES, SHELF LIFE, YOGURTS, CHEESES, LACTIC ACID BACTERIA, ANTIMICROBIAL EFFECTS, EFFICACY.
Citing URL: http://sciencewatch.com/ana/st/probiotics/10juleqShah/