With the advent of the rainy season in Israel, it is an opportune moment to look at the most over - looked ingredient in bread – water – and the role it plays in baking bread.We explore different flours, yeasts, sourdoughs, etc., but take for granted this fundamental ingredient. A thorough understanding of water and its role in the bread-baking process is, however, fundamental for successful baking.While certain breads require special water (matza, for example, uses spring water), most dough is made using regular tap water. Some people suggested that bottled water gives better baking results, and I had the opportunity to test this out myself. Our street once had a water outage on a Thursday, our biggest baking day, and I was stranded without water. We rushed to the supermarket to stock up on bottled water. All our breads that week were made using bottled water, and they came out exactly the same as always. So unless your tap water is indescribably bad, there is no real advantage to paying more money for bottled water.The water content, or hydration ratio, is an important factor in determining the texture and volume of your bread. This ratio of water to flour is measured in terms of weight, not in cups or spoon measures. For example, a hydration ratio of 65% means that for each 1 kilo of flour, there is 650 ml. (650 gr.) of water.Very dry breads have a low hydration ratio, such as matza, which has a 30-35% hydration ratio. Very wet breads, like Italian ciabatta, have a 75-80% hydration ratio. Most regular breads use a hydration ratio of 65 -70 %.Water is the activating ingredient in the dough. You may mix flour, salt, yeast, etc., together, but it is not until the water is added that the chemical processes in the dough formation begin.The stage at which water is added to the dough depends on whether you are mix - ing by hand or machine. When mixing by hand, water is added as the last ingredient. If mixing by machine, it is the opposite. The reason is that in most mixers there is a 2mm. to 5mm. gap between the dough hook and the bottom of the bowl. If you add flour first, there will always be a thin layer of flour at the bottom of the bowl that does not mix properly. Adding water first solves this problem. Different flours have different hydration requirements. Whole-wheat flour requires on average 5-10% more water than white flour, and oat flour 15-20% more.When baking with whole-grain flours, you will need more water to duplicate the texture of baking with white flour, since whole-grain flour is more hygroscopic – i.e., it soaks up more water than white flour. Many make the mistake of simply substituting whole grain flour in a white flour recipe without increasing the water content. The resulting bread is heavy and poorly risen. Water temperature is the dominant factor in determining the rising time of the dough. If it is low, the rising will be slow and sluggish. If warm to hot, it will be highly accelerated. For this reason, using water of different temperatures is the most useful tool for maintaining a consistent baking schedule in any season. As a general rule, lukewarm dough is what is desired. Add water of appropriate temperature that will create lukewarm dough.When working with the dough and shaping the bread, do not add extra flour to the dough to make it workable, as this may alter the hydration factor of the dough and change the texture of the resulting bread. Instead, flour your hands to prevent sticking, don’t flour the dough.Water is a useful ingredient for determining the texture of the crust. If you want a crisp crust, baste or spray the loaf with water prior to baking. Baguettes made in professional bakeries use special steam injection ovens to increase the crispness of the crust.After the bread is baked, leaving the bread to cool on a wire rack allows the water vapor from inside the loaf to evaporate and develop the crust correctly. If left to cool on a tray, the underside of the bread may “sweat,” and water vapor may pool under the loaf, making it soggy.Water may be the simplest ingredient, but its vital role in all stages of bread baking is undeniable. Not for nothing they say that a master baker is one who has mastered the water in his bread.CIABATTA WITH NIGELLA SEEDS Makes one loaf Ciabatta is made from very wet dough, with a hydration factor of 75-80%. Pre-fermented dough ✔ 1¼ cups white flour ✔ ¾ cup water ✔ Pinch of dry, instant yeast (just a few granules) Mix and leave overnight to ferment.Final dough ✔ 1¾ cups white flour ✔ ¾ cup water ✔ ½ Tbsp. salt ✔ ¼ tsp. yeast ✔ 1 Tbsp. oil ✔ Pre-fermented dough ✔ 2 Tbsp. nigella seeds ( ketzah in Hebrew) Mix and knead for 8 minutes. Dough is very wet and sticky. Do not add extra flour. Leave to rise for 3 hours, punching down each hour. Tip dough onto well-floured surface. With well-floured hands, stretch the dough into a rectangular “slipper” shape ( ciabatta in Ital - ian means “slipper”) and place on a baking tray. Leave to rise for a further 30 minutes. Bake at 230º for 35 minutes. ■ Master baker Les Saidel is CEO of the Saidel Artisan Baking Institute (www.saidels.com), which specializes in training and education in the field of organic, healthy, artisan baking and the inventor of Rambam Bread. He also lectures and works as a consultant in the fields of cereal chemistry, health and nutrition.