Showing posts with label health. Show all posts
Showing posts with label health. Show all posts

Friday, January 21, 2011

The Mayo Clinic

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Don says:

"I had the wonderful privilege of touring Mullins Food Products, Makers of mayonnaise.. "(Mayonnaise) doesn't even have to be refrigerated. No harm in refrigerating it, but it's not really necessary." He (the food chemist) explained that the pH in mayonnaise is set at a point that bacteria could not survive in that environment.

(The food chemist) says that when food poisoning is reported, the first thing the officials look for is when the 'victim' last ate ONIONS and where those onions came from (in the potato salad?). Ed says it's not the mayonnaise (as long as it's not homemade Mayo) that spoils in the outdoors. It's probably the onions, and if not the onions, it's the POTATOES.

He explained, onions are a huge magnet for bacteria, especially uncooked onions. You should never plan to keep a portion of a sliced onion. He says it's not even safe if you put it in a zip-lock bag and put it in your refrigerator. "


Ye gods! Where do I start?

The easy bit first: see a previous post on the myth of onions being bacteria magnets. Make sure you read the comments, as the saga went on for a while.

Secondly, there is a popular myth (only in the US for some reason) that mayonnaise is a chief culprit in food poisonings. It isn't. Or at least commercial mayonnaise isn't, as it is made in strictly controlled conditions.

  1. The pH of mayonnaise is kept low, at a level that bacteria cannot survive.
  2. The water activity of mayonnaise is low, meaning that the moisture present in the mayonnaise is not available to the bacteria (or mould) to use and
  3. the product is made in sterile conditions.

The consequences of that last item eludes many people. They think that bacteria just happen. That is as sensible as watching a field, hoping for corn to grow. If you don't plant it, it wont grow.

And "if not the onions, then the potatoes"?

Anything that grows in dirt can have bacteria on it. It will be in an environment where there is E-coli, Salmonella, Clostridium, lots of bugs with long and threatening names. Wherever birds poop and animals roam will have bacteria. You meet up with them every day of your life. And survive.

But if you take some potatoes and cook them there will be no bacteria alive on them.

Put them in a potato salad with mayonnaise and they will still have no bacteria on them.

The biggest problem is when you add bacteria to the salad yourself and then leave the salad sitting unrefrigerated for hours on end. At room temperature bacteria multiply tenfold an hour.

So where do these bacteria come from? Spices, raw unwashed vegetables and, most commonly, poor personal hygiene when preparing the food.

But from the mayonnaise? No.

From onions? No.

From cooked potatoes? No.
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Sunday, July 25, 2010

Coming back for (five) seconds - The Five Second Rule

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I can't believe some people - I only recently caught up with the supposed Five Second Rule and it is just bizarre.

In essence, it says that if you drop something on the floor, you have five seconds where it is safe to pick the food up. It implies that bacteria wont hop onto the food in that time.

Sure.

Now, if it is a crisp (above) there will be minimum contact with the floor and most respectable bacteria would not worry about trying to live on a crisp anyway.

But what if it is a swab the surgeon is going to use on (in!) you in an operation? Still so sanguine?

The more sloppy the food, the more likelihood of bacteria hopping on board as it makes better contact with the floor.

But there are some provisos:

1. If the food is really sloppy it will leave a layer on the floor and there will not be much or any transfer onto the food.

2. The other issue is the one of what is known as the infectious dose. Sure some bacteria will get on the food but there will not be enough to make you sick unless you put it somewhere to grow the numbers a bit. eg too it into the salad you are making for lunch in three hours time.

3. What about interesting things like worm eggs from your dog, cat, hamster? (Erk!)

Sunday, October 11, 2009

Hot and cold on Cayenne


medavinci asks "Is it true cayenne pepper can lower blood pressure and open arteries? Can you just sprinkle it on your food or should it be cooked like curry to avoid salmonella? "

OK, a two part question:

Part 1. Is it true cayenne pepper can lower blood pressure and open arteries?

Maybe. Certainly many foods have physiological effects. A peek on the internet finds a squillion and one sites selling the benefits of cayenne pepper (as well as selling the cayenne pepper) but I couldn't find any mainstream sites, just the herbal fringe. This always makes me suspicious. But I have no reason to doubt that it MAY affect blood pressure. In either direction.

Opening arteries is a little more serious. Certainly people can get flushed in the face after eating peppers, chillies and such like. Is the the same as 'opening arteries'? Maybe. Is it desirable to look flushed? Possibly not. Is it the same as unclogging arteries from too many fries over a lifetime? No.

Maybe it works, maybe it doesn't. By the time you find out, the purveyors of fine herbal remedies will be telling you to eat, drink, roll in something else. But, if you feel that it is good for you, then it is. Isn't it?

Do be aware of the possible risks associated with cancers, especially mouth cancers, from excessive and prolonged consumption of irritants like chilli and pepper.

A rule of thumb that I always have with herbal remedies (like the one in this morning's paper that said magnolia flower tea cures hayfever) is a very simple question: if this cure, cayenne pepper, is so good and so effective, why are the major pharmaceutical companies not growing broad-acres of the stuff? These guys are pretty keen to corner the consumer dollar and never slow to see an opportunity.

Could it be that the efficacy of cayenne hasn't been proved to the level of certainty required by good science and the auditors of the Therapeutic Goods Act?

Remember: Alternative medicine that works is called... medicine.

Part 2: Can you just sprinkle it on your food or should it be cooked like curry to avoid salmonella?

If you are consuming it immediately it will be safe to take 'raw' as it were. If you are putting it into something warm, moist and nutritious and not planning to eat it for a few hours, cook it first.

Saturday, September 5, 2009

Alcohol & Mouth Cancers.

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A local news outlet ran with a story recently that said research had shown that increased alcohol consumption lead to increased mouth cancers.

The trail to try to find the supporting research lead back to a UK cancer body but a request for a reference went unanswered.

The report (SBS News) said that over the last 30 years alcohol consumption had gone up and so had the incidence of mouth cancers. Ergo, drinking increases your chances of mouth cancer. The stated increase was 25%.

Sounds scary. But what if the chance had gone from 1 in a million to 1.25 in a million.

Not quite so scary.

And what else has changed over the last 30 years with things that go into people's mouths?

The Western diet has dramatically increased its consumption of chilli, a known mouth irritant.
Much more processed food.
Much more junk food.
Many more novel food additives, such as artificial sweeteners.
Vegetable consumption has decreased.
Fruit consumption has decreased.
Oral sex has, anecdotally, increased. (human papilloma virus (HPV), is a known carcinogen.)
Beer consumption down, wine consumption up.
Genetically modified foods introduced.

To mention just a few.

I will take their survey just a little more seriously when they can tell me how they allowed for these other changes.

And who paid for the research. And why.
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Sunday, June 14, 2009

Flavoured e-Cigars

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Chairman Bill said "Instead of smoking, I vape in my e-cigar propylene-glycol with nicotine that has flavourings added - banana, vanilla, etc.

Of late I have been 'cutting' the e-liquid with BP glycerine to make it go further, which does tend to dry out the mucous membranes a tad. However, my question is about added flavourings.

Given the e-liquid is vaporised prior to inhalation, what chemicals that commonly appear in food flavourings should I keep well clear of. I believe caramel bungs up the works of the e-cigar due to the sugars, but I'm led to believe that food flavourings can also have some added chemicals that can undergo a transition when vapourised and could be dangerous.

Blowed if I know, Bill.

It's not that a particular flavouring is dangerous. I am assuming that they are not burnt in the normal cigar/cigarette sense. If that is the case, they are all dangerous.

If the vaporisation is not at a particularly high temperature, they should all be OK.
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Thursday, April 2, 2009

Margarine & Butter

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Sara asked for a run down on Margarine.

Normally the image sold to us with margarine is like the one above.

Mother Nature at her most adorable best.

In reality, canola seeds, the main source of oil for most domestic margarine and a close relative of rapeseed and mustard seed, looks like this:

Wholemeal margarine

For convenience, I will limit myself to the manufacturing steps to make canola-based margarines. The process is largely as follows:

1. Grind the seeds and extract the oil using petroleum solvent, usually hexane. Remove as much as possible of the hexane from the oil. The oil at this stage is a greeny-brown colour and has a nutty odour.

2. Treat the oil with caustic soda to neutralise free acids and precipitate gums.

3. Heat the oil with clay to bleach it to a pale yellow colour.

4. Deodorise the oil to remove unpleasant tastes and smells – this is usually done with steam and vacuum.

At this point you have vegetable oil, as you would buy it in the shops. Now...

5. Heat the oil under pressure and heat with finely divided nickel and hydrogen gas to saturate the double and triple bonds in the oil and create a fat that is solid at room temperature. Attempt to minimise the production of trans fats while doing this. The product is now solid, white and bland.

6. Add about 20% water or milk plus emulsifier (typically lecithin) to keep the water-oil suspension stable.

7. Add flavours (usually milk and/or milk solids) to give taste. Salt may also be added.

8. Add vitamins A & D to fortify it.

9. Add colour to make it look more appealing.

10. Put a lid on it.

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Margarine has the same fat content (80-85%) as butter.

Margarine has the same calories as butter.

Margarine use was widely adopted when someone said butter was bad. No-one stopped to wonder if margarine was good. It just wasn't butter and butter was bad. Presumably butter was bad because it contained cholesterol. Now the notion that dietary cholesterol is a problem has been largely discredited. The concern now centres on the saturated fats in the diet.

Butter does have higher saturated fat levels than margarine.

The other thing to be aware of is that there is table margarine and cooking margarine. Cooking margarine is used in the biscuit and cake industry and is a harder (more saturated) fat than table margarine.

Is margarine bad?
No, not bad in the 'avoid at all costs' sense but nor is it 'natural' in the way the advertisers and their sunny yellow fields would like us to believe.
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Wednesday, April 1, 2009

Locked away in a room full of celery...

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I used to be intrigued by a story I was told as a kid, that hard boiled eggs use more energy to digest than they contain and so you loose weight if you eat them.

Sounded dodgy to me, even then. It implied that if you were locked in a room with nothing but water and hard boiled eggs, you would starve to death.

But apparently that is the case with celery.

The calories in food are a measure of energy content. For something we eat to be a source of "negative calories," it must provide fewer of these units of energy than we expend in consuming it. Yet everything contains calories, so at first this concept appears impossible.

Therefore, the hunt is on for ingestibles whose energy content is not released into our bodies because we humans lack the ability to break them down — it doesn't matter how many calories these goodies have, provided we can't extract them.

Cellulose in plants is one such substance: although it contains a goodly amount of carbohydrates, they are packaged in a form we cannot digest, so we fail to absorb their calories.

Celery has about 6 calories per 8-inch stalk, making it a dieter's staple.

Its ingestion can result in negative calories, but it is a fallacy to believe that effect has to do with energy expended in chewing. Though chewing might feel like a somewhat strenuous activity, it burns about the same amount of energy as watching paint dry. It is the bodily energy devoted to the digestion of the green stalks that exhausts calories.
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Thursday, March 26, 2009

Prostate Cancer and Red Wine

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The Australian media was abuzz last week with a report that alcohol consumption increases the chances of prostate cancer. Two drinks a day will increase your risk by 20%. The risk increased with the number of drinks consumed in a day.

Before I pour my home brew down the drain, there are a few things I need answered.
(If you haven't read my previous post, now's a good time. I'll wait.)

Causality
Could alcohol consumption cause/increase the risk of prostate cancer? Possible.
Could prostate cancer risk cause drinking? Improbable.
Could a third factor be in play? Possible. Here are a few possible other factors:

People who drink large amounts of alcohol a day are often overweight. Is BMI a factor?
The consumption of chips, nuts and snack foods is probably proportional to drinks consumed.
Big drinkers often eat more meat.
Is consumption of other foods an issue - fibre, greens, fruit?
Do drinkers live longer, due to the heart benefits of alcohol, and get cancer due to longevity?

That will do. I'm sure we could come up with more. You can begin to see the difficulty of extracting two issues from a very complex life-matrix.

Crud Factor
Is a crud factor in play? Possibly. Sometimes a big survey like this finds statistical significance where no practical significance exists or will average out differences in reports.

Compare the following two extracts from studies into prostate cancer and alcohol consumption:

Our present study suggests that consumption of beer or liquor is not associated with prostate cancer. There may be, however, a reduced relative risk associated with increasing level of red wine consumption. Int. J. Cancer: 113, 133–140 (2005).

Wine or beer consumption was unassociated with prostate cancer; however, moderate liquor consumption was associated with a significant 61–67% increased risk of prostate cancer. International Journal of Epidemiology 2001;30:749-755

Looks as if beer is neutral, red wine gets a sort of a plus and spirits get a sort of a minus.

So does the report mean anything?

Too early to tell really but I will put a punt on the benefits of moderate alcohol consumption outweighing the possible down side.
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