Modern chefs use ingredients such as pectin, guar gum and soy lecithin to make their life easier in the kitchen and achieve superior results in their preparations. Those ingredients are easy to use and can be of help to chefs at home, too.
The main barrier preventing their wider use at home is a resistance to anything that is perceived as chemical. If it is not natural, common sense says it is bad.
But distinguishing what is natural from what is artificial is not easy. It is perhaps more of a philosophical and cultural distinction than a chemical one. What people grew up with is often what they consider as being natural.
Most of the uncommon ingredients used by modern chefs are additives. Their use is widespread in industrial food. Additives do not have a good reputation, but aren't evil, per se.
The reason additives are used in a particular product needs to be understood. Some are included in food to hide the low quality of the raw materials. Others, like colourants, are used to make the products look better than they really are.
Additives can be used to add structure, thicken liquid, stabilise emulsions, and create textures. They can be an ally in the pursuit of health, by helping those with intolerances to avoid ingredients like gluten and dairy.
The home chef should become familiar with two of these unusual ingredients: agar-agar and xanthan gum.
Agar-agar is extracted from seaweed, making it a better choice for vegetarians, as the gelatin commonly used at home is produced using pig hides. It helps lower the calories of a meal as it makes the need for flour and eggs redundant, and allows jams to thicken even if the amount of sugar is reduced.
Xanthan gum is one of the most popular thickeners in modern cuisine because of its versatility. It is also used as emulsifier to stabilise the union of lemon and oil, or the spices in a vinaigrette. It helps to give gluten-free dough a sticky consistency.
In this week's recipe, I use a very small amount of xanthan gum to thicken the pesto sauce, which otherwise tends to separate. I will also detail some other chef's secrets that are not normally disclosed in cooking books. The result will be a perfect dish of spaghetti al pesto.
Spaghetti al pesto
50 basil leaves (about 65 grams)
200ml extra virgin olive oil
50 grams pine nuts
2 garlic cloves
80 grams grated parmesan
Salt to taste
- Toast the pine nuts in a saucepan over a low heat, being careful not to burn them.
- Choose basil leaves which have not yet flowered. Basil loses its flavour with water so you should wipe the leaves with a dry cloth to clean them.
- Basil also oxidises and becomes bitter with heat. To avoid this, put your food processor in the freezer one hour before using it.
- Place the basil, pine nuts, garlic, salt, half of the oil and one ice cube into the food processor and process them for no more than 10 seconds.
- Transfer the sauce to a bowl, mix in the rest of the oil and the parmesan.
- Weigh the sauce, calculate 0.2 per cent of the weight, and whisk that amount of xantham gum into the pesto until fully incorporated.
- You can keep pesto in the fridge under a layer of oil but it goes off quickly so eat it within a few days.
- In a stainless steel pot bring five litres of water to the boil. Add 40 grams of coarse salt, let the salt sit for one minute and add 400 grams of spaghetti. Stir gently to prevent the spaghetti from sticking together.
- Transfer to a large bowl and stir in the pesto.
Healthy Gourmet is a column by private chef Andrea Oschetti