1. Food Security Availability Accessibility Nutrition Safety Clker.com
KarachiFoods.com
Accessibility
Food Security
Nutrition
iamasocialentrepreneur.com
Safety
Clker.com
Promoting global food security, to me, is the grandest of the Grand Challenge. To me, the critical barriers are food availability – do we have enough food for everyone when the debate between the balance of food vs fuel is at stake, food accessibility – can we provide an equal access to food globally?, nutrition – undoubtedly, we have malnutrition problems around the world, and last but not least food safety- can we provide safe and clean food to our world citizens?. I got 4 min and 30 seconds left so let’s me jump into the area of my interest for this Grand Challenge which is Food Safety. India st
newshopper.sulekha.com

2.
Although food is meant to provide consumers full source of nutrition, it is also contaminated with several bad stuff. Food poisoning, in theory, can be 100% preventable. But in practice, that doesn’t happen. The main sources of poisons can be categorized into two categories: chemicals such as pesticides and biological contaminations such as bacteria and parasites.
indochinapioneer.com

3. hangthebankers.com
leanbodyworks.com
koraorganics.com
Quick summary of amount of agrochemicals used
Health affects: breast cancers, Parkinson’s disease, memory disorders, dermatologic conditions, cancer, depression, neurological deficits, misscarriages and birth defects.
Agrochemicals (high amounts required to deal with pest resistance) --Agriculture, pesticides, food security and food safety by Fernando P. Carvalho
telegraph.co.uk

4. care2.com
nbafoodadvocate.com
withonebreath.wordpress.com
how.com
We all probably know too well of the common foodborne pathogens – let it be, E.coli, salmonella, listeria and others. They are small but causing big problems of foodborne illnesses. The sources of these contaminations are varied. They can be contaminated by animal feces used as as fertilization, improper preparation and storage. The effects of these pathogen contaminations are costly. WHO has reported that contaminated food contributes to 1.5 billion cases of diarrhea in children each year, resulting in more than three million premature deaths.

5. Current Detection for Chemicals
en.wikipedia.org
labmate-online.com
Some of the current methods to detect chemical contamination are Gas chromatography, mass spectrometry, HPLC which are expensive and require skilled workers to interpret the results.

6. Culture Technique Sources:
Bacterial colonies growing on a plate of nutrient agar. Hans Knoll Institute. Jena, Germany.
For the biological contamination, the traditional plate-count method where you take food sample, grow in selective medium or food for specific bacteria to increase the numbers of bacteria so that it can be detected. When you take the enriched liquid samples before plating on a solid food medium. This whole process take at very least 3-5 days. By the time, the results come out, some of the food would have been exported out.
The easiest and most conventional method is to take a sample of food and then put it a generic liquid food for bacteria to grow. Once you have enough of bacteria which takes about 1-2 days then you put the liquid food onto different plates.
Each plate contains different food that is specific to different bacteria. For example, this purple bacteria will only grow on purple plate. The pink bacteria can only grown on pink plate. You would have to do this as many different plates as you want to test. After a day or two, if your food was contaminated with the bacteria, you will find something like these on the plates. And you can then identify whether they are toxic bacteria from different plates you use.
It is easy and inexpensive BUT it takes forever and very tedious to do. So can do it faster?
Sources:
womensabworkout.com, textbookofbacteriology.net, Bio-rad.com

7. Polymerase Chain Reaction (PCR)
DNA extraction
Faster and more sensitive method is called PCR. Basically, it is a method to amplify DNA of bacteria.
However, it is more complicated and more expensive than before.
Sources: womensabworkout.com, textbookofbacteriology.net, Bio-rad.com

8. Enzyme-linked immunosorbent assay (ELISA)
DNA extraction
Therefore, we have other alternative methods that detect bacteria using different principle. This method can also be applied for chemical detection as well. We will be detecting the whole bacteria or chemical with a special molecule called antibody. This antibody can bind specifically to only one type of target. So, we will coat each well with one type of antibody. For example, the first well will be coated with antibody specific for E.coli, the next one will be coated with antibody specific for Salmonella. If you put a mixture of food culure in each well and if it is contaminated with E.coli, this well will show up. If this doesn’t, it will not have a color. So, this is much easier than the DNA amplication method before, but it’s not perfect yet! Although it is quick, it is still expensive because of these antibodies are expensive. So, what can we do?
Enzyme-linked immunosorbent assay (ELISA)
Sources: womensabworkout.com, textbookofbacteriology.net, Bio-rad.com

9. Microarray technology
Microarray Technique
Microarray technology
Therefore, To lower the cost, we can use less antibodies by using this technique called Microarray, which can spot a very tiny spot of antibody (picoliter or nanoliter) on the slide or a plate and then you can use the same principle as ELISA as before. This ends up saving more reagents and antibodies.
However, it is still need skilled labors to work with and an expensive detector to detect the signal.
Sources: womensabworkout.com, textbookofbacteriology.net, Bio-rad.com

10. dinochiesa.net
fingerrollsandfoldingchairs.wordpress.com
What we need to ensure our food safety is simple but challenging. We need something that is easy to use by both producers and consumers, cheap enough that can be accessed by all, fast such that by the time the test results come out the food still remains sellable, and more importantly it must be versatile for all types of food.
changing-river.com
www2.tv-ark.org.uk