Beans, peas or lentils: what’s the difference?
Well, they all come from plants called legumes, more technically the plant family Leguminosae, also known as Fabaceae. Beans and peas are defined as the seeds that grow in pods of these legumes. Pulses are the dried seeds, however green beans and green peas are called vegetables. All clear? No? Let me go further.
Traditionally, when the seeds in the pod are oval or kidney-shaped, they are called beans. They can then be sub classified by colour such as red beans (e.g. pinto, kidney, black) or white beans (e.g. cannellini, navy). [These colour names are not at all baffling… black beans are red beans and navy beans are white beans?!] Round seeds in the pod are called peas, unsurprisingly split peas are whole peas split in half. Then there are lentils, which are legume seeds that are flat disks, also classified by colour (green, yellow, red). Finally, to add to the confusion, soya beans are classed as an oilseed rather than a pulse by the UN Food and Agriculture Organization.
Jelly beans are none of the above, but can be classified by colour if you so wish.
Pulses are a cheap, low-fat source of protein, fibre, vitamins and minerals, such as iron, phosphorus, and folic acid, and they count towards your recommended five daily portions of fruit and vegetables. Soya bean is higher in fat – there is a table at the bottom of this blog to show you some comparisons and the nutrition claims that could be used on product labels.
Beans, Beans good for your heart…
Pulses are high in complex carbohydrates and fibre, which means they are slowly digested and give a feeling of satiety. But this leads to the issue of wind… the complex carbs called oligosaccharides are not broken down by the enzyme digestive process in the small intestine, so they move to the large intestine undigested. It is the bacteria that live here that finally break down the oligosaccharides, and this is the process that produces the gas.
Spare a thought for the scientists who carried out the study that determined the total daily volume of gas for 10 volunteers eating their normal diet plus 200 g baked beans per day, which ranged from 476 to 1491 ml (median 705 ml)**. They’ve most certainly bean there, done that, conflatuations to them.
I can’t finish this blog without a section on the students’ staple, the baked bean, a certain producer of which sells 1.5 million cans every day in the UK. Most canned baked beans are made from haricot beans, also known as navy beans. The cans were originally imported from America with the first batch arriving in the UK in 1886 and sold in Fortnum & Mason as a foreign delicacy. Now they are perhaps not quite so upmarket?
What’s in a bean?
Below is a table of the nutrient content of a few types of cooked pulse. All data are from The Composition of Foods compiled by us at Food Databanks at the Institute of Food Research, using the Nutritics nutritional labelling software. If you would like a free 7 day trial of the click here.
That’s all for now, I am off to watch Pirates of the Carob bean.
*Definitions: ‘high fibre” products contain 6g of fibre per 100g or at least 3g of fibre per 100 kcal.
‘low sugar’:has less than 5g of sugar per 100g.
‘source of’ means it contains at least 15% (the significant amount) of the nutrient reference value in 100g
‘High in’ means it contains at least twice the significant amount of the mineral or vitamin in 100g
**Investigation of normal flatus production in healthy volunteers, J Tomlin, C Lowis, N WRead Gut, 1991,32,665-669