Water is, along with flour, the primary ingredient in breadmaking. However, this ingredient often receives little attention compared to others such as yeast, salt, or dough conditioners. This may be due to the ease of obtaining water and its consistency in the same location. Nevertheless, while it is true that under normal conditions, variations in the quality of public water supplies in one location usually do not affect the breadmaking process, differences in water quality in different places can have an impact. When we speak about water, three factors must be considered: the quantity of water in the formulation, the quality of the water, and the water temperature.

Quantity of Water

It is well known that each type of bread requires a different amount of water in its formula, and this amount of water influences its processing. In general, bread that requires a large amount of water, such as ciabatta, results in very soft, sticky, and challenging-to-work dough. To address this issue, block fermentation is often used to strengthen the dough, in addition to the typical dusting of flour, which temporarily reduces stickiness until the flour is absorbed by the dough. In these cases, the lower dough resistance to the action of the mixer complicates gluten network formation, requiring longer kneading times. Some bakers solve this problem by not incorporating all the water initially so that gluten formation is easier and adding the remaining water progressively once the gluten network is formed. This high hydration yields bread with a more open and irregular crumb structure due to the dough’s lower resistance to the expansion and bonding of air pockets and a crunchier crust. Water also has a diluting effect, resulting in somewhat bland bread, which is why it’s common to add flavor-enhancing ingredients like sourdough starter, malted flours, rye, or others.

In the case of dough with low water content, such as Spanish “Candeal”, the water is quickly absorbed into the flour at the beginning of kneading, forming dough balls or pieces that most mixers cannot handle, hindering gluten network development. In these cases, refining is typically used to develop the gluten network. This technique involves passing the dough through rollers repeatedly over time. This way, the hydrated wheat proteins receive the necessary mechanical work to form a gluten network, resulting in a fine-textured, very consistent dough with a tightly-knit crumb structure. The bread obtained is denser with a fine and uniform crumb structure, as well as lighter and less crunchy crusts. Between these extremes, there are many formulations whose processing has adapted to the characteristics generated by moisture variations in the dough.

However, for the same preparation, it is common to adjust the amount of water in the formula. Most bakers make this adjustment by eye, based on the dough’s consistency. Changes in dough hydration with the same formula usually stem from changes in flour quality, although, as we will see later, they can also be influenced by dough temperature. It seems obvious that drier flour, which provides less water to the dough, requires more external water. However, flours are generally consistent in this regard, with moisture content ranging from over 14% to less than 15% (legal limit in many countries). What is less known is that variations in certain flour components also affect dough consistency. The higher the protein content of the flour, the greater the hydration needed to achieve a similar dough consistency. The same applies when flour damaged starch or fibre content is higher. Contrary to what some believe, protein quality does not affect dough hydration but influences kneading time, dough stability, and tolerance to over-kneading.

To determine the amount of water to be incorporated, the most well-known equipment is the farinograph, from Brabender, although other devices that provide similar results exist, such as Perten’s DoughLab, Chopin’s mixolab, and consistograph. In general, these devices prepare a standard dough and analyse its consistency by measuring the dough’s resistance to the mixing blades’ action, determining whether a specific flour requires more or less water to achieve consistent dough. These devices also help determine the optimal kneading time or dough tolerance to over-kneading. They are costly equipment and may not be affordable for small businesses but are accessible to industrial bakeries. More and more flour mills have these devices, and their analyses can be requested when purchasing flour. It is desirable that the flours used have similar water absorption values, eliminating the need to adjust formulation moisture.

In terms of water content in formulations, it should also be noted that some ingredients incorporated into certain preparations contribute a significant amount of water. This is the case with milk, which has a water content close to 90%, or eggs, whose egg whites also contain water percentages close to 90%, while egg yolks contain slightly less than 50% water. When oil is added, it may be advisable to reduce the amount of water in the formulas since oil reduces dough consistency. Unlike water, oil does not evaporate during baking, resulting in softer, less crispy, and more juicy bread.

Water Quality

Water quality can also affect dough and bread characteristics, but significant differences in water quality are not common within the same city or town, especially in public water supplies. Obviously, water used for baking must be potable, a guarantee provided by public water networks, and free from strange tastes and colours. The presence of these flavours and colours can be transferred to the bread, affecting its quality, although it is becoming increasingly rare for public water to have these issues. Other factors that affect dough include water hardness and pH, but, as mentioned earlier, there are usually no significant variations in the same area. However, more significant differences can exist from one city to another, and the same formula may be affected when used in different locations, although other factors, such as different machinery or temperatures, could have a more significant impact.

Water hardness is determined by the amount of certain salts, such as carbonates, present in the water. Harder water typically yields slightly firmer dough, while softer water produces weaker dough. For these effects to be noticeable, the differences in water hardness must be significant, similar to reducing the salt content in dough. Hard water can also cause calcium deposits in pipes over time.

Water pH can also alter the action of yeast since yeast performs better at slightly acidic pH levels. Extremely acidic or alkaline water may slow down fermentation, but normal pH variations in water usually do not pose problems in this regard. It is possible that in some areas, it may be necessary to slightly increase yeast content in dough compared to others.

The effect of certain metal ions in water or the presence of chlorine on fermentation has also been investigated, but, as mentioned earlier, differences in water quality in the same locality usually do not generate problems in this regard.

Water Temperature

This is the factor that has the most significant impact on our process for the same formula and is more easily controllable. Yeast performs optimally at temperatures near 40°C, so the closer we get to this temperature, the more yeast activity there will be. The dough temperature depends on factors such as the type of mixer, kneading time, the quantity of ingredients in the mixer, the formula itself, as well as ingredient and bakery temperatures. The higher the dough temperature, the more yeast activity, resulting in more consistent dough. Conversely, colder dough is usually softer and stickier.

In the same bakery and with the same formula, differences in dough temperature are caused by variations in bakery, flour, and water temperature. These variations are normal since, in summer, bakery, flour, and water temperatures are higher than in winter. To compensate for these differences, it is challenging to modify bakery or flour temperatures quickly and economically, but it is straightforward to adjust water temperature. Therefore, water temperature should be regulated to achieve consistent dough temperatures throughout the year. In winter, there is usually no issue with the water’s starting temperature, and some adjustments can be made with a water heater. However, in the summer, we may need water at a lower temperature than what is obtained naturally. This is why it is advisable to have a water cooler in bakeries.

In cases where the dough is going to be refrigerated after kneading, it is crucial to minimize the dough temperature. This is because, although yeast tolerates cold well and can even be frozen, yeast’s cold tolerance sharply decreases when fermentation begins. Therefore, if the dough is going to be chilled later, fermentation initiation should be avoided as much as possible. Cold water is typically added in such cases, resulting in slightly softer dough than usual. This can be compensated for with less water in the formula or by using flours with higher protein content and better farinograph absorption.