Cooking: temp of a warm object

Cooking means constant self-tutoring. The tutor speculates about the actual temperature of a warm object.

Yesterday I took a glass casserole dish of mac and cheese from the oven. Its baking temp was 177C.

An hour later, most of the mac and cheese had been served from the dish. Moving it, I was surprised how warm it still was to the touch.

Yet, how warm was it? I didn’t have a convenient way of measuring, so I opened a browser tab and found, whose members seem to agree that about 60C is dangerous to touch for more than a second or two.

The casserole dish wasn’t hot; rather, just surprisingly warm. I’d estimate it was about 40C.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Lifestyle: meal planning, part 0

Cooking keeps me self-tutoring. The tutor mentions a meal that was indispensable last school year.

Most weeks, I don’t work outside the home, but my wife does, and my kids go to school (grades 8 and 10 this fall). Increasingly, therefore, my role is domestic – cleaning and so on – of which meal planning can be the most challenging.

Although many people don’t like to admit it, we’re about to embark another school season. With relief from the higher evening temperatures, savvy, proactive sorts are already cooking meals to freeze for easy thaw and serve a few months from now, when life will be busy.

A standby meal for us last year – one the kids really enjoyed – was fresh bread with canned beans. Three to five hours before they needed it, I’d put the ingredients in the bread maker and start it up. Often I’d also open the cans of beans, put them in the pot, and leave them there without the heat on.

When the three needed dinner, I’d often be tutoring. No problem: my wife would just turn the dial on the stove, then take the finished bread from the bread maker. Dinner in five!

Beans and bread, eaten together, are complementary proteins, which means you get the protein benefit of eating meat.

My wife loves to cook, and doesn’t prefer shortcut meals. However, with her job and the children’s activities, she’s pushed more in that direction.

I’ll be sharing more of our meal solutions:)


Mader, Sylvia S. Inquiry Into Life, 11th ed. Toronto: McGraw-Hill, 2006.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Lifestyle: Bacon as a food: Is it too fatty?

Lifestyle is all about self-tutoring. The tutor looks into a long-time curiosity: the viability of bacon as a food.

Most of us probably love bacon. Is it too fatty to be taken seriously as food? To quote HAMlet: To eat, or not to eat, bacon: that is the question.

I decided to compare bacon with peanut butter and cheese. My specific interest is the fat content versus protein content. My findings:


I’m surprised how well cooked bacon compares to the other two.



Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Lifestyle: cooking: sweet potato vs yam

Learning to cook means, for me, constant self-tutoring. The tutor reflects about sweet potatoes vs yams.

To surprise the family, I made sweet potato pie a couple of weeks back. I used the occasion to experiment with sweet potato vs yam: I went to the grocery store and bought one of each. Then, using the same recipe, I made one pie with the yam, the other with the sweet potato.

It turns out that, likely, both the sweet potato and the yam were actually sweet potatoes. Yams, apparently, are not so common in supermarkets here; rather, they’re common in Africa and the Caribbean.

The visual difference between the sweet potato and the (so-labelled) yam I bought at the grocery store: the sweet potato was white, while the “yam” was orange. However, sweet potatoes can be either color.

So, very likely, I made two sweet potato pies. They turned out well:)


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Lifestyle, nutrition: eggs and cholesterol

The tutor compares egg yolk to egg white and generally considers eggs.

I’ve been told that it’s best to eat the egg white without the yolk, but I’ve never believed it. Today I looked it up.

About 43% of an egg’s protein is in the yolk. However, the yolk contains more of folate, zinc and many other nutrients than the white. The abundance of nutrients in the yolk has clearly inspired the comment that “the yolk may contain all the fat, but it also contains most of the vitamins and nutrients.”1

Some people worry about the yolk because that’s where the cholesterol is found – perhaps around 180mg. However, a growing opinion is that one egg per day probably doesn’t affect the cholesterol of a healthy person (although it might for some people facing specific health conditions, such as diabetes).

When people told me to only eat the egg white, they clearly meant to avoid the fat and cholesterol.


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Lifestyle: convection oven vs regular oven

The tutor looks into the advantages of a convection oven.

I’ve never owned a convection oven or used one, but years ago I knew a very pragmatic coffee shop owner. He baked his own goods, and he had a convection oven. I knew he wouldn’t have it unless it was particularly useful.

The difference between a regular oven and a convection one is that a convection oven blows heated air against the food, rather than simply heating the chamber. The result is quicker cooking – perhaps by about 25%.

Convection is useful for cooking meat, heavier baked goods like cookies or muffins, and even pastries. However, products that are potentially unstable, such as cake or souffle, probably should not be cooked with convection.

Relative to regular oven cooking, convection cooking should be done at a lower temperature setting, perhaps by 25F (14C). The food needs to be checked earlier.



Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Turkey: dark vs white meat

The tutor compares the fat content of white and dark turkey meat.

Apparently, cooked turkey thigh (dark meat) is about 5.9% fat, whereas cooked turkey breast (white meat) is about 1.2% fat. Lean roast beef, by comparison, is about 6.4% fat.

Happy holidays!


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Spreadsheets: Excel: convert() function

The tutor mentions Excel’s convenient conversion utility.

I used to wonder, casually, what a nautical mile is compared to an ordinary mile. Not anymore: today I discovered Excel’s convert() formula, which is among the Engineering ones in More Functions, in the Formulas pane. convert() has many possibilities, which you can discover by selecting it, then clicking “Help on this function”.

The basic syntax is

=convert(quantity, “first_unit”,”second_unit”)

To convert one nautical mile to regular miles, for instance, I key in


Excel responds with 1.150779.

For cups to litres, I key in


Excel responds with 0.23664.


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Units: cups to mL

The tutor looks at cup to mL for US, Canadian, and metric.

A metric cup is 250mL; US, 236.6mL. A Canadian cup is 227.30mL.

My impression is that 250mL is typically used as a cup. (I can’t imagine someone measuring 237mL of flour.) However, the difference is only about 5%, between those two.

Compared with the Canadian cup, though, the metric cup is about 10% more.


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Cooking: are green potatoes dangerous, and why?

The tutor shares information about the hazard of green potatoes.

Potatoes are meant to grow covered beneath the soil. When a tuber (the edible part of a potato) gets exposed to the sun, its exposed cells develop chlorophyll, so turn green: they become photosynthetic so they can produce carbohydrates, rather than just storing them.

To protect themselves from being eaten, the exposed, newly-photosynthetic cells also produce dangerous toxins related to strychnine. Hence, the wisdom that any green parts on a potato must be discarded.

A study reported in 2006 looked at the toxicity of green potatoes. Results showed that the green skin can host the toxins at dangerous concentration; however, the flesh of the green potato was not found to – in that study, anyway. Yet, the researchers urged caution: the toxins can persist in the human body for more than a day, and even low-level concentrations of them may cause symptoms difficult to detect.

To be as safe as possible, one can obey the old wisdom and discard all green parts of a potato.


Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.