Since the main role of potatoes is to grow into a plant, a potato contains a lot of starch. So what is this starch made of? Plants just like humans use glucose a sugar to provide energy to grow and thrive. They make this glucose using photosynthesis. In this process, they use sunlight and carbon dioxide from the air to make glucose. In order to prepare for times that less glucose is available or, like the case of potatoes, to prepare for future growth, plants need to store this glucose.
They by linking a lot of these glucose molecules together, creating a long chain of glucose molecules. These long chains of glucose are starch and are what we would call a polysaccharide!
Note, we humans use a similar concept for storing excess glucose, however, instead of making starch, we make glycogen. Starch is an energy reserve for the potato, consisting of long chains of glucose molecules. The glucose molecules can link to each other in roughly two ways.
One by forming a long, mostly linear, chain of glucose molecules. Each glucose molecule except for those at the end is linked to two others.
The molecule formed this way is called amylose. Alternatively, the glucose molecules can connect in a more branch-like structure. In this case, some glucose molecules are connected to 3 other glucose molecules, creating offshoots of the linear chain.
This branched structure is called amylopectin. Starch contains a mixture of both amylose and amylopectin, just how much of each depends on various factors. For instance, starch from potatoes is different from that of rice. But also, younger potatoes can have a different ratio than older ones and different potato varieties will have different ratios.
Potato starch is present throughout most of the potato in the form of granules. Each granule will consist of a large number of starch molecules, including both amylose and amylopectin.
The granules are very tightly packed hence their storage function , so tightly packed that the density of these granules is higher than that of water 1.
It is why raw, uncooked starch sinks in water. The starch molecules are packed in such a way that they create a semicrystalline structure. This very well-organized structure makes starch insoluble in water at room temperature once you start heating the starch granules that all changes, as we discussed for cooking potatoes and starch thickeners.
The smaller granules are spherical or oval in shape whereas larger ones are cuboid or even irregular in shape. Potato starch granules tend to be on the large side. This all impacts the behavior of the different starches and makes them all slightly different. Even though starch granules are mostly made up of starch, a few other molecules may have come in as well. Although potatoes are a vegetable, in the UK we mostly eat them as the starchy food part of a meal, and they're a good source of carbohydrate in our diet.
Because of this, potatoes do not count towards your five portions of fruit and vegetables a day , but they can have an important role in your diet. Potatoes are a healthy choice when boiled, baked, mashed or roasted with only a small amount of fat or oil and no added salt. When cooking or serving potatoes, go for lower-fat or polyunsaturated spreads, or small amounts of unsaturated oils, such as olive or sunflower oil.
Leave potato skins on where possible, to keep more of the fibre and vitamins. For example, eat the skin when you have boiled or baked potatoes. If you boil potatoes, some nutrients will leak out into the water, especially if you have peeled them. To stop this happening, only use enough water to cover them and cook them only for as long as they need. Storing potatoes in a cool, dark and dry place will help stop them sprouting. Do not eat any green, damaged or sprouting bits of potatoes, as these can contain toxins that can be harmful.
Bread, especially wholemeal, granary, brown and seeded varieties, is a healthy choice to eat as part of a balanced diet. Wholegrain, wholemeal and brown breads give us energy and contain B vitamins, vitamin E, fibre and a wide range of minerals. White bread also contains a range of vitamins and minerals , but it has less fibre than wholegrain, wholemeal or brown bread. If you prefer white bread, look for higher-fibre options. Some people avoid bread because they're concerned about having a food intolerance or allergy to wheat, or they think bread is fattening.
However, completely cutting out any type of food from your diet could mean you miss out on a range of nutrients that you need to stay healthy. Bread can be stored at room temperature. Follow the "best before" date to make sure you eat it fresh. Cereal products are made from grains. Wholegrain cereals can contribute to our daily intake of iron, fibre, B vitamins and protein.
Higher-fibre options can also provide a slow release of energy. Wheat, oats, barley, rye and rice are commonly available cereals that can be eaten as wholegrains. This means cereal products consisting of oats or oatmeal, such as porridge, and wholewheat products are healthy breakfast options.
Many cereal products in the UK are refined, with low wholegrain content. They can also be high in added salt and sugar. When you're shopping for cereals, check the food labels to compare different products. For more advice, read about healthy breakfast cereals. The small intestine does not digest resistant starches, meaning they work in a similar way to dietary fiber. Resistant starches pass through into the colon, where they begin to ferment.
During the fermentation process, these resistant starches feed the friendly bacteria present in the gut. There are several possible health benefits to eating resistant starches in potato starch, including the below. Raw potato starch, which a person can sprinkle over food, contains this type of starch. During a study , males with excess weight ate just 15—30 grams g of resistant starch every day.
They showed increased insulin sensitivity than participants who had not been eating foods with resistant starch. However, it is worth noting that female participants did not experience the same results as the males in this study. Researchers call for further studies to determine the reason. Learn natural ways to improve insulin sensitivity here. As resistant starch ferments, it feeds the healthy bacteria inside the colon as it converts into short-chain fatty acids.
Butyrate is a short-chain fatty acid that forms during this process — it plays an important part in the cells of the colon. However, most of the research into butyrate and resistant starch has involved animals and not humans.
Therefore, more human studies are needed to outline whether these benefits affect people. Learn 10 ways to improve gut health here. A study found that eating resistant starch helps people feel fuller after a meal.
During the study, participants ate 30 g of resistant starch each a day for 6 weeks. This reduced the number of hormones that triggered hunger in otherwise people who had excess weight. Individuals who ate resistant starch also had increased levels of compounds that helped them feel less hungry in the morning. Resistant starch in the diet may help aid weight loss efforts by increasing the feeling of fullness after a meal and increasing the length of time a person feels full.
Learn 10 tips to lose weight here. Potato starch does not generally have many health risks for a person. Resistant starches, such as potato starch, act similarly to fiber, meaning there are very few side effects after consumption.
However, some individuals may find that eating large quantities of potato starch triggers gas and bloating. There are several alternatives to potato starch. A person can substitute it with one of the following options:. Learn 9 substitutes for cornstarch here. Potato starch is not the same as potato flour — the former is the extracted starch from crushed potatoes. To make potato flour, a person peels whole potatoes before cooking them, drying them, and grinding them into a fine powder.
The two products differ in a number of ways. While potato starch only contains starch, potato flour comprises starch, fiber, and protein.
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