How healthy is frozen bread, really? A series of videos posted on TikTok claim that the process of freezing bread does, in fact. healthier. The science behind this theory is a bit confusing, though.
When the bread is cooked, it turns the moist, bubbly dough into a soft, fluffy loaf. The heat of the oven, combined with the water in the dough, causes the starch in the flour to expand and gelatinize.
The same thing happens when flour is added to a sauce to thicken that sauce.
Gelatinized starches are easier to digest
Gelatinized starches are easier to digest, which makes the glucose (sugars) these starches contain easier for our cells to obtain. This is true of many freshly cooked starchy foods, especially those that are low in fiber or made from finely ground flour – such as white bread or potatoes.
According to Science Alert, some evidence suggests that this type of rapidly available glucose may increase insulin levels immediately after a meal. Although insulin is important because it helps cells use glucose for energy (or store it for energy later), too much insulin can make you feel hungry and can even make you gain weight.
This is how resistant starch appears
When foods containing this gelatinized starch are cooled, the expanded starch shrinks, becoming what is known as resistant starch.
These resistant starches cause enzymes in the digestive tract to break them down – which means it will be harder for our cells to take up the sugar these starches contain. It means that resistant starch is less likely to cause a “spike” in blood sugar and insulin.
The degree to which resistant starch can form depends on the baking temperature of the bread and whether it is then refrigerated or frozen. The rate of shrinkage is almost twice as high in the freezer. than in the refrigerator, which means that more resistant starch will form.
Plus, freezing the bread traps the water inside – making it fresher and softer than if you kept it in the fridge, where the water will be lost and the bread will harden.
Should you freeze bread?
A study of ten healthy people looked at the effect of frozen white bread and then toasting it. They also compared store-bought bread to homemade bread.
For the homemade bread samples, freezing and thawing the bread reduced blood sugar levels by 31% within two hours.
Interestingly, toasting the fresh bread also reduced the rise in glucose by 25 percent.
This effect was even greater when the homemade bread was frozen, thawed, then toasted – reducing the blood sugar response by 39 percent. This effect could help with hunger, as glucose and insulin levels will not rise as high after eating frozen bread.
But when commercial, store-bought white bread was used, freezing before toasting did not improve the body’s blood sugar response.
This could reflect the different ways in which commercial bread is made compared to homemade bread. The ingredients used or the way the bread is cooked and then frozen can reduce the effect of freezing on the formation of resistant starch. The evidence is not quite clear.
Other, more recent research has also shown similar results.
It is worth noting that these effects only exist for a few hours after eating the bread.
Frozen bread would help lower blood sugar levels
While freezing bread before eating it can help lower blood sugar at one meal (and have little effect on the next meal as well), the long-term effects on appetite, weight gain, or risk of certain diseases (like would be diabetes) is not known.
Resistant starch can be found in many other cooked and chilled starchy foods, such as potatoes, pasta and some types of rice.
Basmati rice appears to form more resistant starch than fluffier types of rice (such as arborio rice).
In addition to being harder to break down than freshly cooked starch, resistant starch provides nutrients to microbes living in the colon. This helps maintain a healthy balance of bacteria in the gut, with the bacteria releasing chemicals on the cells that line the colon, helping us to have a healthy metabolism.
