SNIPPETS

www.saafost.org.za
Volume 10. Number 05. 2005
013-075NPO



  1. A one-day SAAFoST Career Roadshow is to be presented in Durban, Pretoria and Cape Town. Food personalities and experts will address students on a variety of subjects of interest to students entering the food industry as a career.
  2. SAAFoST will be taking part in the 18th International Congress of Nutrition being held in Durban on 21 September. A two hour mini symposium featuring eight well known local and international nutrition and food experts has been organised by the Association . The title of the event is: "Key Issues in the Food Science / Nutrition interface".
  3. All branch BGMs were held during July. The Northern Branch has a new Chair, Jaci Barnett (CSIR: Bio/ Chemtek), new vice Chair, Prof. Lucia Anelich (Tshwane University of Technology) and two new committee members, Moira van der Linde (Pick 'n Pay) and Don Kaka (Quest). The new Cape Branch Chair is Dr. Jessy van Wyk (Cape Peninsula University of Technology), vice Chair is Morongwa Themba (Nampak R & D) and new committee members are Lisa Ronquest (Pioneer Foods), Jacques vd Bergh (Appletiser), Kareline vd Spoel (Savannah). The KZN Branch Committee, chaired by Lizette de Fleuriot (Rennie) remained unchanged.
  4. Prof. Piet Jooste has been awarded the Dairy Mail "News Maker of the Year" accolade for 2004, in recognition of the success of the Symposium on Dairy Hygiene & Safety and his Presidency of the National Committee of the International Dairy Federation.

THE BEST FRUITS FOR DIABETICS

Fruits provide us with the best source of vitamins, phyto-chemicals, and fibre - all important components of a healthy diet. Although fruits contain natural sugars, diabetics should not forego their benefits, but should choose fruits wisely, based on the glycemic index (GI), a measure of how fast carbohydrate foods (including fruit) are converted in the body to blood glucose. Diabetics should focus on fruits that are low on the GI (below 55) since these release sugars more slowly into the blood stream. Some good choices are:

* An average-sized apple (GI score: 38)

* Cherries (22)

* Grapefruit (25)

* One average-sized orange (44)

* One average-sized pear (38)

* One plum (39)

Intermediate-GI fruits include banana (55); cantaloupe (65); mango (55); papaya (58); and pineapple (66). High-GI fruits include dried dates (103) and canned fruit cocktail (79).SAMIC NEWSLETTER NR 12 - 2005-04-08 (See also www.foodfacts.org.za for a new article on this subject. Ed.)

A Historical Cohort Study Of The Effect Of Lowering Body Iron Through Blood Donation On Incident Cardiac Events. Meyers Dg, Jensen Kc, Menitove Je.

BACKGROUND: Low body iron may protect against atherosclerotic cardiovascular disease through limiting oxidation of low-density lipoprotein cholesterol. Observational studies suggest that donation of blood might be associated with reduced risk of cardiovascular events. METHODS: .... 1508 adults who had donated more than one unit of blood each year and 1508 age and sex-matched adults who donated only a single unit in that 3 year period. .... RESULTS: .... Events occurred in 6.3 percent of frequent and 10.5 percent of casual donors. ... Events were less frequent in female donors than in male donors ..... CONCLUSION: Frequent and long-term blood donation is associated with a lower risk of cardiovascular events. Transfusion. 2002; 42(2):1135-9 also see http://www.pubmed.com (Join me and become a blood donor! Ed)

FDA Data On Acrylamide In Food Data Updated

Data taken from the FDA's Total Diet Study for 2003 includes acrylamide concentrations for many of the foods sampled for the TDS. The FDA has recently posted updated, tabulated information on Acrylamide in Food. Food e-News Edition 240: 15 - 22 June 2005

Canadians Develop Test For BSE In Live Cattle

<>Vacci-Test, Canada have developed a simple, reliable and cost-effective diagnostic tool for the detection of infectious brain diseases in live cattle, such as bovine spongiform encephalopathy (BSE). Such brain diseases are detected through a blood test to determine the presence of protein 14-3-3, a marker for brain infections. The test will be available for use on farms and ranches shortly. (From Ag Professional).
Food e-News Edition 240: 15 - 22 June 2005.

EFSA Report On Semicarbazide In Food

<>The European Food Safety Authority has published its opinion on semicarbazide in food. The authority has gathered data on the occurrence of semicarbazide in all food types, formation of semicarbazide in foods, evaluated analytical methods and performed a risk assessment. The panel concluded that the semicarbazide concentrations found in foods is not a concern for human health. RSSL Food E-news 242-29 June to 6 July 05. For the full story: http://www.rssl.com/OurServices/FoodENews/NewsLetter.aspx?ENewsletterID=112#0

Magical Kiwi Fruit

Kiwi fruit (Actinidia chinensis L.) polysaccharides exert stimulating effects on cell proliferation via enhanced growth factor receptors, energy production, and collagen synthesis of human keratinocytes, fibroblasts, and skin equivalents.

Within physiological engineering, exogenous carbohydrates were recently confirmed as pharmacologically active compounds. To investigate potential dermato activity, purified polysaccharides from kiwi fruits (Actinidia chinensis L., Actinidiaceae) were characterized concerning monomer composition., linkage types and mol. wts. and were tested, under in vitro conditions, for regulating activities on cell physiology of human keratinocytes, fibroblasts, and skin equivalents. It was shown that the polysaccharides led to a doubled collagen synthesis of fibroblasts compared to the normally strongly reduced biosynthetic activity. Chemical Abstracts 142:423724

Dietary Flavonoid Research

Dietary flavonoids are known for their antiplatelet activity resulting in cardiovascular protection, although the specific mechanisms by which this inhibition occurs has not been fully established. Objective: The aim of this study was to investigate the interaction of nine flavonoids representative of various chem. classes, with platelet responses dependent on thromboxane A2 (TxA2) generation and on receptor antagonism, and to analyze the structural requirements for such effects. Conclusions: The inhibition by specific flavonoids of in vitro platelet responses induced by collagen or arachidonic acid seems to be related, to a great extent, to their ability to compete for binding to the TxA2 receptor. Chemical Abstracts 142:423424

Food Price Trends: January 2004-April 2005

Year-on-year food price inflation depends largely on the goods contained in the food basket that is monitored. In order to have a more representative picture of the products and different prices available to the consumer the NAMC extended the price survey to include more brands within the various food categories. Weighted average prices were then calculated using the volumes sold by each chain store as weights. Year-on-year inflation gives a good indication as to where prices are heading, as seasonal price trends tend not to effect this calculation since the same month in different years is compared. For this month's food price release we calculated two sets of year-on-year price changes: January 2004 to January 2005 and April 2004 to April 2005. Products whose prices decreased in the year ending January 2005 also tended to show further decreases in the year-on-year calculations for April 2005. The products that showed significant price decreases were pilchards (-10.7%), flour (-10.8%), super (-25.5%) and special (-30%) maize meal, cheddar cheese (-13.3%), frozen peas (-11.4%), pork sausages (-34%), pork chops (-29.9%), butternut (-13.2%), and bananas (-15.9%).

Over all, there were few products whose prices increased by more than 10% year-on-year (April 2005). These are: Frozen corn (19.6%), beef brisket (13.9%), onions (20.3%), tomatoes (11%), and oranges (10.3%). Having taken 75 different food products into account, food prices increased overall by 0.16% for the period January 2004 to January 2005, decreased by 0.75% for the period April 2004 to April 2005, and on average decreased by 0.09% between January and April 2005. SAMIC NEWSLETTER NR 21- 2005-07-01. Compiled by Prof Johann Kirsten and Ms Michela Cutts for the National Agricultural Marketing Council 30 June 2005. Enquiries: Lizette Mellet, Tel: 012 341 1115, lizette@namc.co.za

A Role For N3/N6 Fatty Acids In Cancer Treatment

Decreased n-6/n-3 fatty acid ratio reduces the invasive potential of human lung cancer cells by downregulation of cell adhesion/invasion-related genes.

The objective of this study was to examine the effect of alteration in the n-6/n-3 fatty acid ratio on the invasive potential of human lung cancer A549 cells. These results demonstrate that a decreased n-6/n-3 fatty acid ratio reduces the invasion potential of human lung cancer cells by probably downregulating the cell adhesion/invasion-related molecules, suggesting a role for the ratio of n-6 to n-3 fatty acids in the prevention and treatment of cancer. 2005151475 MEDLINE. PubMed ID: 15661810 (The Northern Branch lecture for October will be on n3/n6 fatty acids. Ed.)

Insects Develop Resistance To GM Crops

A team led by Professor Anthony Shelton from Cornell University in New York State US, has found that insects can develop resistance to genetically modified crops, when plants expressing one Bt gene or two Bt genes are planted in proximity to each other. Their findings are recorded in an open access article in the Proceedings of the National Academy of Sciences (PNAS, 2005 102: 8426-8430).

Researchers from Cornell created three types of genetically modified broccoli plants. Two of the broccolis each expressed a different Bt (Bacillus thuringiensis) toxin (Cry1Ac or Cry1C) and a third broccoli expressed both toxins (pyramided). Diamondback moths (Plutella xylostella) were used in the study. These had developed resistance to Bt toxins resulting from the long standing use by farmers and gardeners, of Bt toxin sprays. (The authors explain that while Bt toxin sprayed on leaves quickly degrades in sunlight and sometimes does not reach the insect, in genetically modified plants such as Bt GM maize, the plants express the Bt toxin in their tissues which makes them much more effective against insects which bore into the stems, such as the European corn borer). The moth populations carried genes for resistance to Cry1Ac and Cry1C at frequencies of 0.10 and 0.34, respectively. They were released into caged growing areas with either single-Bt gene plants, dual gene plants or mixed populations and allowed to reproduce for two years. After 24-26 generations of selection in the greenhouses, the concurrent use of one- and two-gene plants resulted in control failure of both types of Bt plants. When only two-gene plants (pyramided) were used in the selection, no or few insects survived on one- or two-gene plants. This suggested that the concurrent use of transgenic plants expressing single and two Bt genes will select for resistance to two-gene plants more rapidly than the use of two-gene plants alone.

Explaining this effect, Professor Shelton said that it is easier for an insect to develop resistance to a single toxin. If the insect then encounters the same toxin in a dual-gene plant it becomes more rapidly resistant to that toxin. When one line of defense starts to fail it puts more pressure on the second toxin in the pyramided plant to control that insect. On this basis, Shelton considers that single-gene plants should be discontinued as soon as dual-gene plants become available. This is particularly so for small farmers in China and India who do not have plots of land large enough to create refuges. Refuges are parts of a field where non-Bt plants are grown. Refuges create opportunities for Bt-resistant insects to mate with insects which do not have resistance, providing offspring which are susceptible to the toxins.
Food e-News Edition 240: 15 - 22 June 2005

UK Unveils Amended Nutrient Profiling System

29/07/2005 - Food officials in the UK have developed a model that ranks the health status of foods according to the sum of their nutrients, reports Dominique Patton.
Nutrient profiling has also been proposed under the European health claims regulation, although industry has vigorously campaigned to remove this requirement.
The model developed by the UK’s Food Standards Agency (FSA) has evolved through consultations over the last few months into a ‘simple scoring’ system, which rates the overall balance of nutrients in the food.
FoodNavigator.com | europe 29/07/2005

Snippets - contributions are welcome. Edited and produced by Dr. B Cole. – drcole@cybersmart.co.za / Fx 011 660 6444 with the help of the Northern Branch Committee.