n RE SEARCH lth by various factors. The first one is the differences in starch types. For example, the potato consists of two types of starch: amylose and amylopectin. The amylopectin absorbs more water as a result of which the molecules are more open. This ensures that the digestion of starch and absorption of glucose is faster. Amylose, by contrast, absorbs less water resulting in a tighter structure. This causes slower digestion resulting in a lower GI. In bread the degree to which the grain is ground determines the GI. The longer the grinding process of the grains, the faster the digestion. This is because the fibre and consequently the barrier to converting the starch has then been removed, which results in a higher GI. This is the reason why whole grain bread scores a GI of 40 while white baguettes have a GI of 95. Combination of nutrients ntake due to a food shortage, Professor Wim Saris indicates. least eight trial subjects are given 50 grams of potatoes to eat, that’s how it starts. The next step is that, in the first hour, you take blood samples every fifteen minutes to determine the sugar content in the blood. In the second hour you take samples every thirty minutes. These outcomes are put into a graph, which can then be used to determine the GI of the product’, Saris explains. The test distinguishes three categories: 0-55 is low, 56-69 is average and 70 or more is high. The average GI of the potato is between 70 and 80 and is therefore high. Factors that determine GI Saris explains that the GI is determined Of course, we don’t eat only carbohydrates. But we do often eat carbohydrates in combination with fat and protein. Fat is retained in the stomach for a longer period of time. Fat and protein slow down the gastric emptying – and therefore the digestion of starch – in the small intestine. For this reason, potato crisps ‘only’ have a GI of 55 and fried potatoes lower the GI of the average potato to 65. Furthermore, the boiling of food has an influence on the GI. Boiling makes starch granules swell up and softens the food. This increases digestibility. So al dente spaghetti has a GI of 44, while longer cooked spaghetti scores 64. The importance of insulin But how does the GI of food relate to the metabolism in the body, Saris asks his Audience. ‘It’s much more important to look at the insulin content that causes it. You absorb carbohydrates which causes the insulin content to rise. This opens the tissues so that the sugars can enter them to burn. If you eat food with a high GI, your insulin level rises more. If you eat several times a day, the insulin level will also rise more often and the body’s fat burning process will drop. The body stores fat in adipose tissue. When you eat products with a low GI, more fat will be burnt. We’ve known for a long time that obesity is the result of not being able to burn fat. If you continuously have a high insulin level, you close the metabolism for burning off fat. So it would be very good to eat only once or twice a day instead of six times a day. You then give your body the opportunity to burn off fat. A low GI therefore helps to lower the blood sugar level. Moreover, a low GI results in more satisfaction. As digestion takes longer, the body starts to produce satisfaction hormones. So this means that a low GI diet helps to lower the bodyweight. If an overweight person does lose weight, a diet consisting of more protein and low GI products helps him to keep his weight down’, Saris explains. Low GI foods are healthier Saris points out that a low GI leads to a healthier life. This is why Agrico’s new table potato label Carisma, only contains potatoes with a low GI. Where an average variety scores around 75, varieties that may be packaged under the Carisma label show a GI of not more than 53, is Agrico Director Jan van Hoogen’s message. He says that the idea for this new health stamp is the result of a cooperation between Agrico and partners in Australia. Scientists and growers have been working together since 2008 in their search for a potato suitable for a low GI diet. After extensive research, in 2010 they had already successfully introduced the Carisma label in the well-known Australian Coles supermarket chain. Today, this supermarket sells 3.5 million packages of this label annually. In Australia, you can advertise low GI products as a health claim, but that’s forbidden in Europe. That’s why Agrico is taking a different approach with this label. Potato World 2016 • number 1 5 Pagina 4

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