• Akis

The thin white line

“When it comes to pasta, there is nothing worse than eating a plate with overcooked spaghetti”

Italians insist that pasta should be eaten al dente. This, to some people sounds like an exaggeration, others think of it as non-negotiable. But does really al dente makes a difference on how we perceive pasta? The answer to this has much more substance than someone might think, but if we want to put it simply, it can be only a big yes.

The science of al dente

Al dente literally means “to the tooth”. It describes the state when pasta is not cooked fully through, when it still retains in its center a firm texture. It is simply the feeling of resistance we get when our teeth bite pasta. The same applies to rice in risotto. To understand deeper al dente, we need to get a grip on the underlying processes governing pasta cooking. Those processes are responsible for the actual transformation of raw to cooked pasta and relate to the physical alterations that undergo its main components, namely the carbohydrates, and the proteins.

Carbohydrates, in the form of starch, represent roughly 70% of dried pasta and are organised inside semi-crystalline granules that are roughly spherical, while varying in size. The starch granules are embedded into the gluten protein meshwork, which is built from the two major wheat proteins, gliadin and glutenin.

Starch exists in two forms, having its glucose molecules bound each other either in a linear (amylose) or branched (amylopectin) fashion. When pasta is thrown into hot water, a process known as starch gelatinization comes into play. Starch starts to absorb water and the granules swell. That is why pasta gets bigger (approx. 1.7 times its original size) upon cooking.

In parallel, the proteins coagulate, meaning they change conformations, expose more surfaces to form new bonds each other, and stick together to form a dense mesh that prevents major leak of starch into the medium (pasta water). Interestingly, both starch gelatinization and protein coagulation do not need more than 80-85 °C to occur. This, theoretically, suggests that pasta doesn’t require boiling water to cook properly.

Unavoidably, granule swelling will partially disrupt the protein cage, hence some starch (particular amylose that is linear and diffuses easier) will leak out into the pasta water, which will subsequently turn milky. This starchy water (the ‘secret’ ingredient in Italian pasta recipes) will eventually help the cook, at the end of the cooking, to dress the pasta nicely with the sauce.

As cooking evolves, the water penetrates deeper into the pasta and interacts with more and more granule layers. Al dente refers to the point that the very center of the pasta is still underdone, something that is empirically defined by a thin white line, which is barely visible to the human eye when we bite pasta to test doneness.

At this point (usually 1-2 min before indicative cooking time), the pasta is ideally transferred from the water pot into a pan where the sauce cooks in the meanwhile. It will finish cooking there, using these last moments to get coated and catch the sauce.

Why al dente

As a pasta lover, I strongly believe that al dente contributes decisively to a great pasta dish. The firm structure forces us to spend more time biting and chewing, thus pasta stays longer in the mouth. In this way, we have more time to perceive and enjoy better, not only taste and flavour, but also the actual chewing process that adds to the overall pleasure and mouthfeel. Believe me, no matter how good the sauce is, there is nothing worse than eating overcooked pasta.

Additionally, al dente-cooked pasta is handled better by our digestive system. Because of its rigid structure, the digestive enzymes need to work harder to break down starch into simple sugars (glucose). The latter enters into the bloodstream at a slow pace, thus its blood levels do not spike up. This reflects on pasta’s glycemic index that is a measure of the effect that foods have on the blood sugar levels. Higher the glycemic index of a food, faster the blood sugar increases after eating that food. Pasta has a relatively low glycemic index that gets even lower when it’s eaten al dente. This might not have significant meaning to most people but is rather important for some (like diabetics) that need to pay attention when they consume foods high in carbohydrates.

How to get it al dente

To catch the pasta al dente during cooking, we either follow carefully its indicative cooking time, or we judge through biting and tasting. However, sometimes, no matter how much we pay attention, the pasta ends up soft and clumpy on the table. That is because other factors, like the quality, as well as the protein content of the pasta per se matter a lot to its cooking outcome.

Pasta is made from hard (durum) wheat, which has, compared to common (soft) wheat, a gluten type that supports better the shaping and cooking of pasta. But durum wheat (like other grains) is not universally the same. Its quality, namely the protein content and type, depends on many factors like the grain origin, the cultivation conditions, the harvest time, etc.

Typically, the protein content of commercial pasta lies between 11-15%. Higher the protein content, the more rigid the pasta, better it holds its shape during cooking and longer it stays al dente.

It’s very difficult to overcook a pasta with more than 14% proteins!

Also, pasta’s drying conditions and methods have an important impact on its physical properties and how it cooks.

A combination of high quality durum wheat semola with proper climate conditions and artisanal production methods makes great pasta. The best example comes from Gragnano, a small town near Naples, the birthplace of modern pasta or the “city of pasta” as it is called. Pasta in Gragnano is made from excellent durum wheat that grows in an ideal climate regarding the blend of wind, sun, and humidity. The pasta dries naturally, in low temperatures, and under a gentle breeze from the sea and the mountain.

If you see a package of pasta with the officially recognised and protected Pasta-di-Gragnano designation, you know automatically that this is the real thing. Get it, cook it, and you will have a completely new experience, eating a dish that the pasta itself feels like the undeniable protagonist. Rough and not sticky texture, strongly al dente, catching the sauce perfectly, overall providing us with a great mouthfeel.

“What a pasta!!” That I said to myself the first time eating Gragnano pasta.

Copyright by greek chemist in the kitchen 2021. All rights reserved.