Dear Pierre, I have renamed this thread and interspersed some remarks.
on 2005-07-03 06.26, Pierre Abbat at [EMAIL PROTECTED] wrote: > While metricating someone's food calculations, When you say 'metricating' do you mean changing old pre-metric measures into metric units? When you do this which metric units are you aiming for? As I understand history there were 5 or 6 different metric systems (with names such as cgs, mks, mksA, etc.) before all of these were incorporated into the International System of Units (SI) in 1960. There is now only one metric system. > I went looking for a blueberry > jam recipe (she had conflated similar-sounding units and I can't metricate it > properly without a recipe) and found this: > http://www.topology.org/tex/mj/mj3.html > > The burnworth of fat is 37 and of carbohydrate is 16. Converting these to kcal > (because I've heard them in that unit and I wanted to check) I get 8.8 and > 4.06. I have not heard the term 'burnworth' before. I have used 'energy content' and 'energy value'; of these I prefer 'energy content'. When I have changed the units to SI units I do not then seek to change them into one or other of the old metric systems as you have done here I just leave them in SI. In this case I would not change 37 kilojoules per gram or 16 kJ/g any further (although some purists might insist that I use 37 MJ/kg and 16 MJ/kg because kilogram is the base unit in SI) > Anyone know what the value for protein is? The values I've heard in > kcal/g are to only one significant digit, which isn't very good for > calculation. Here is a reasonable set of approximations, but be aware that not all fatty acids and not all carbohydrates provide the same amount of energy The dietary fibre can be a bit tricky too as it depends on whether the fibres are broken down by bacteria in your large intestine. Fat - 37 kJ/g Alcohol - 29 kJ/g Carbohydrates - 16 kJ/g Protein - 17 kJ/g Dietary fibre - 13 kJ/g Water - 0 kJ/g > As to the blueberries, do any of you know how many grams of blueberries (or > any other cowberry - it shouldn't be much different) it takes to make a > kilogram, or a liter, of jam? Looking over a range of jam recipes, it seems to me that jams are usually about half fruit and half sugar with sometimes a little water added to dry fruits and a little citrus added for pectin to help with setting (and to add a little flavor). So if you have 500 grams of blueberries you should add 500 grams of sugar and after boiling away some of the water this will yield a little under a kilogram of jam. The yield will also be just under one litre so you will probably 'fill' 5 x 200 mL jars to just below the brim. Here's a good recipe to get you started. http://www.inmamaskitchen.com/RECIPES/RECIPES/Basics/jms_preserves/jam_berry .html Cheers, Pat Naughtin Geelong, Australia 61 3 5241 2008 [EMAIL PROTECTED] http://www.metricationmatters.com This email and its attachments are for the sole use of the addressee and may contain information that is confidential and/or legally privileged. This email and its attachments are subject to copyright and should not be partly or wholly reproduced without the consent of the copyright owner. Any unauthorised use of disclosure of this email or its attachments is prohibited. If you receive this email in error, please immediately delete it from your system and notify the sender by return email.
