How to Read the Cider Yeast - the LAG Phase 🍏🍎 with Kesser and Steen - Nature and Innovation 📙 скачать в хорошем качестве

How to Read the Cider Yeast - the LAG Phase 🍏🍎 with Kesser and Steen - Nature and Innovation 📙

the LAG Phase - How to Read the Cider Yeast - Kesser and Steen are preparing a ‘yeast starter’ for a cider brew based on apples. That is why Professor Hendricks has suggested that they read up on what is called the LAG phase when working with yeast that is to be propagated / used for cider and wine etc. When Kesser and Steen are going to start making their yeast starter for cider, it is a good idea to understand what happens in the first time after the yeast cells have been put to work. This period is called the LAG phase. You can think of it as a kind of adaptation period, where the yeast just has to settle into the new environment before it starts to multiply and make alcohol. When the yeast cells are transferred from their previous environment to the must or starter, they experience a change in their surroundings. The sugar content, temperature, oxygen and available nutrients may be different, and this means that the cells do not immediately start dividing. Instead, they spend time activating a lot of internal processes. They build new enzymes, make cell walls, adjust their energy apparatus and absorb oxygen, which they need to form sterols and fatty acids. All of this prepares them to grow quickly and efficiently when the conditions are right. Although it may seem like nothing is happening during the LAG phase, it is actually a very important part of the yeast's life cycle. A strong and healthy lag phase provides a more stable and uniform fermentation afterwards. If the yeast starter is given enough time in this phase, subsequent growth and alcohol production will proceed more reliably, and problems such as sulfur odor or sluggish fermentation are avoided. The LAG phase can last from a few hours to over a day, depending on how big the difference is between the old and new environment, and how healthy the yeast is to begin with. For cider brewing, this means that Kesser and Steen must ensure that the yeast is not thrown into an environment that is too harsh. Give it some oxygen, some nutrients and the right temperature, and the LAG phase will run smoothly and the yeast will be ready to grow as the sugar in the apples is converted into alcohol and aromas. In this way, the start of the process becomes just as important as the fermentation itself, and understanding the LAG phase can be the key to a successful cider. Adding the Yeast The way Kesser and Steen have set it up is actually a classic little starter that they have had made. The apples are cooked so that there are no wild yeasts or bacteria left, and the small sprinkle of salt helps to keep unwanted microbes away. The sugar gives the yeast some easy fuel to start with, and once the mixture has cooled down to room temperature, it is ready to have wine yeast added. When Steen asks if the yeast can just do the rest on its own, the answer is basically yes. When you add the dry or liquid wine yeast, it goes through the lag phase we talked about earlier. This means that the cells first take some time to get used to the environment of the apple juice. They adapt by absorbing some oxygen and building the substances they need to be able to divide. When they are ready, they will enter a growth phase, where they multiply rapidly, and then they will start to convert the sugar into alcohol, carbon dioxide and a lot of aromatic substances. It is therefore important that the starter is not too hot or too cold when the yeast is added. Room temperature is fine, but if the liquid is still above 35 degrees, the yeast can be damaged. Conversely, it goes too slowly if the mixture is cold like a refrigerator. When the temperature is right, the yeast will actually do the rest of the work itself. The only thing Kesser and Steen can do to help the process along is to ensure that the yeast gets a good start with some oxygen, the right nutrients and enough time in the layer phase. When there is no more sugar available, the yeast no longer has anything to convert into energy. This is the most obvious obstacle: without sugar, there is no fermentation. But there are also other factors that can slow down the process long before all the sugar is gone. A high level of waste products in the liquid, especially ethanol (alcohol), but also organic acids and sulfur compounds, is toxic to the yeast cells. Alcohol is essentially a solvent, and when the concentration becomes high enough, it destroys the membrane and enzyme function in the yeast cells, so that they die or go dormant. You could say that yeast production stops or slows down when there is either no more fuel to work with or when its own waste builds up to a level that becomes toxic to it. That's why cider and wine people often work with nutrient supplementation, proper temperature control, and oxygenation at the beginning so that the yeast is strong enough to ferment quickly and cleanly. #cidermaking #winemaking #kesserogsteenpåtur Copyright 2025 - Flamme Rouge 🚩 Nature