How to Begin a Sourdough Starter From Scratch (It’s Easy!)

By combining two ingredients – flour and water, it is easy to begin a sourdough starter from scratch. Once started, sourdough starts are easy become second nature to maintain. Taking seven days or less to establish, beginning a sourdough starter is just the start of a journey to endless meals (and desserts) made from scratch.

I started making sourdough recipes after 13+ years of eating gluten free. Creating a starter was the first step in my sourdough journey. I am passionate to educate and inspire you to explore the world of sourdough!

How to make a sourdough starter

The process of creating sourdough starter comes from combining two ingredients – flour and water. By mixing these two ingredients together and allowing them to sit at room temperature, the beautiful process of fermentation can begin.

This is all thanks to wild yeast. When wild yeast attaches to the flour and water, carbon dioxide is released – causing a sourdough starter to begin.

Wild yeast exists in the air and it is the key to baking (and brewing). This yeast is different from bakers yeast and brewers yeast based on the genetic compounds which make up the yeast.

Wild yeast is a natural yeast which releases carbon dioxide, causing good bacteria to grow and fermentation to occur. This ultimately helps your bread rise! We love sourdough for recipes like bread, cinnamon rolls and pizza crust!

Benefits of Sourdough

Sourdough has been around for years! The oldest sourdough starter can be traced back to the clay pots found in Egypt. (Can you imagine if someone found the first sourdough bread recipe?!)

Some of the oldest maintained sourdough starters for bakeries have been around for hundreds of years. People love sourdough because of the benefits like:

• Reduced amount of gluten after fermenting for 24+ hours.
• Lower in carbohydrates and has a smaller glycemic index than whole wheat bread made from commercial yeast.
• Fermenting bread reduces phytate (aka physic acid) levels. Phytate binds minerals like calcium, copper, iron and zinc – which prevents their absorption.
• Endless amounts of recipes with added health benefits.
• Fresh bread – whenever you want!

Now that you know a little bit about what sourdough is and the benefits, how do you begin a sourdough starter?

8 Steps to begin a sourdough starter

1. To begin a sourdough starter, ensure the following items are on hand: one jar (preferably glass), one spoon (wooden or metal), flour (preferably organic) and water. A measuring scale can also be helpful.
2. Start by sterilizing your glass jar. To sterilize your mason jar, boil it in water for 10 minutes. Allow the jar to cool at room temperature before adding flour and water. Alternatively, if the glass jar is new, simply wash it with hot soapy water, rinse and dry before using. Ensure your spoon is also sanitized or cleaned well.
3. Place the mason jar on your kitchen scale and set the scale to ‘zero’. This will ensure as you add flour and water to the mason jar, the scale does not reset itself back to ‘zero’ to make up for the difference in weight as the weight of the flour, water and spoon are added in.
4. Next, measure 1 ounce of flour and 1 ounce of water into the mason jar. (To convert ounces to grams, 1 ounce is 28.3495 g flour and 28.3495 g water). Stir. Allow the jar to sit on the kitchen countertop (covered with a cheese cloth or towel) for 36 hours. At this point, you may begin to see some fermentation occurring in the form of tiny little bubbles. This is a good sign!
   • We like using whole wheat flour to begin a sourdough starter. See notes below in FAQ for more details. If you do not have whole wheat flour, all purpose flour, rye flour, or bread flour will work.
   • If you cover your sourdough starter with a lid, it is important to ensure it is NOT screwed on tight. Too tight of a lid can cause the jar to explode because there is no way for the gas / pressure to release.
5. After 36 hours, begin encouraging further fermentation by discarding at least half of the starter into the trash. To the jar, add 1 ounce of flour in 1 ounce of water to the remaining sourdough starter. Allow to sit at room temperature for 24 hours.
   • At this time you may feed your starter with whole wheat flour or begin using another flour.
6. Repeat step 5 (Stir starter -> Discard at least half -> add 1 ounce flour + 1 ounce water -> allow to sit for up to 24 hours) for three or more days, following the process of discarding and feeding the starter with 24 hour (or longer) increments in between.
   • Weather pending: Repeat these steps for as long as necessary if the sourdough starter is taking longer than 24 hours to reach the ‘peak’. We have had sourdough starters take as long as 10 days to begin successfully creating lots of bubbles under a 24 hour timeframe in the winter because our house is colder.
   • At this point it is normal for the sourdough starter to seem ‘thick’ in consistency (similar to brownie batter) when you pour new flour in. When it is time to discard, the starter will ‘thin’ to a similar consistency of pancake batter.
7. Around day 7, you may have successfully made a sourdough starter from scratch! At this point, the starter will become stronger each day and will need less time to reach peak hydration (IE it’s highest point before it falls after a feeding).
   • Peak hydration is also referred to as ‘100% hydration’. This means the sourdough starter has reached the ‘peak’ or highest hydration level point after feeding before it begins to ‘fall’ again within the jar.
   • To test if your sourdough starter is ready, complete the float test or use a rubber band to track growth. The sourdough starter float test occurs when you take a spoonful of starter and place it in a cup or bowl of water. If the sourdough starter floats, it is ready to use! To measure with a rubber band, place a rubber band at the top of the starter once it is fed. Once the starter has grown to double in size, it is at it’s peak. These two tests are a good way to tell you are well on your way to a the beginning of a great sourdough journey!
8. Once your sourdough starter has reached ‘maturity’, you can begin utilizing the sourdough starter within recipes or you can maintain it through the countertop or fridge method.
   • At the point of seven days (or more), your sourdough starter should be reaching maturity. This is the time were you can decide what recipe you would like to use with an active sourdough starter. The amount of sourdough starter you are throwing away or pulling aside for future recipes is called ‘discard’. 

Note, you will not want to reserve the sourdough discard for future recipes during this first week. All sourdough discard will need to be thrown away during the first week.

Unfortunately, the sourdough discard will not have strong enough fermentation to act properly within a recipe. Instead, use these tips to begin with a small amount of flour so the sourdough starter is not expensive to begin.

Realistically the first seven days of creating sourdough starter is the only time that you will have to throw away starter. Discarding sourdough starter must occur to control acidity and to help control the size of the starter.

Begin a sourdough starter (Day by Day)

Day 1: Add 1 ounce of flour and 1 ounce water to a sterilized jar. Stir and allow to sit covered (with a cheese cloth or plastic wrap) for up to 36 hours. Small bubbles may begin to form.

Day 2: Check to see if any bubbles have began within your starter 24 hours after beginning your starter. If none, wait 12 more hours (totaling 36 hours after beginning) before discarding sourdough starter and feeding. During day 2, discard at least half of your starter into the trash and add 1 ounce of flour and 1 ounce of water. Stir and allow to sit, covered.

Day 3: The next day, 24 hours after your sourdough starter has been fed, discard half of your starter into the trash and add 1 ounce of flour and 1 ounce of water. Stir and allow to sit, covered.

Day 4-7 (+): After the first couple of days, your sourdough starter may begin to rise faster. The first time it doubles in size is commonly called the ‘false rise’. This is a good sign! Your starter will continue to rise faster as it becomes more mature.

Follow the same process (stir -> discard at least half -> add 1 ounce flour and 1 ounce water -> stir and sit) for the next few days until your starter reaches it’s peak faster than 24 hours. Continue this process until your sourdough starter grows and and falls rapidly. Next, use within a sourdough recipe, like bread or bagels!

The process of maintaining a sourdough starter is easy! There are two common methods: the countertop method and the refrigerator method. Both methods are listed below and follow the same process to maintain (stir, discard, feed, repeat) though the timeline on these maintenance steps is different.

Maintaining a Sourdough Starter- Countertop method

A sourdough starter can sit on the kitchen counter for roughly 24-48 hours without being fed and discarded. This is because the starter becomes ‘hungry’ and the the flour needs something to ‘eat’ in order to continue fermentation.

If a starter has reduced from the peak and gone flat (meaning it has minimal (or no) bubbles), it definitely needs to be fed. If there has been a long time (over 48 hours) in your feeding schedule between the last time the starter has been fed, give it a little extra water and flour for it to come back stronger than ever.

A sourdough starter in a warmer 65-75 degree household will reach the peak faster than a house which is cooler than 65 degrees. I find in the summer months, my sourdough starter takes anywhere from 4-12 hours to reach a peak hydration level before slowly reducing. If it is cooler, my starter will take closer to 24 hours to reach peak hydration level.

Maintaining a Sourdough Starter – Fridge Method

A mature starter can last in the fridge for over one week at a time between feedings. By putting a fed sourdough starter in the fridge (IE discarding some or half, feeding it and immediately placing it covered in the fridge), it will slowly begin to ferment and will not need to be fed as quickly.

Cover loosely with a lid, plastic wrap or a combination of plastic wrap with beeswax wrap over the top. This will help to ensure a skin does not form on the top of the sourdough starter.

Refrigerated sourdough starter can have a hardened skin because the flour is of the frequency sourdough starter is stirred. This skin is harmless and can be stirred in when feeding the next time.

Allowing a sourdough starter to sit in the fridge where temperatures are cooler causes the fermentation process to slow. This causes it to need less frequent feedings.

For starter which sit in the fridge for an extended period of time (over a week), they may create a thick grey colored ‘skin’ and water sitting on the top of the starter. Simply scrape this away before being feeding again or place a spoonful of starter beneath the skin / water into a new glass jar and feed.

If you are ready to make a recipe with your sourdough starter and are utilizing the refrigerator method between feeds, simply remove from the fridge, feed and allow to sit on the countertop until it has doubled in size.

Increasing Sourdough Starter Amount

In order to increase your starter to use it within a recipe, add equal parts of flour and water to your starter. I personally like to keep my sourdough starter small as I do not utilize it more than 1-2 recipes per week (IE I bake two loafs of bread weekly). I maintain my sourdough starter at 1 to 2 ounces at all times.

Because of my small starter, I look at a recipe and add an equal amount of flour and water to meet the required sourdough starter amount.

For example, if a recipe requires 8 ounces of sourdough starter, I will add equal parts of water and flour – IE 4 ounces of flour and 4 ounces of water.

This ensures I have at least 1-2 ounces of starter left after I discard my sourdough starter within a recipe. As a rule of thumb, if you end up utilizing and discarding majority of your starter you can grow your starter. Having even as much as a dime size amount of starter left will allow you to maintain it.

Sourdough Starter FAQ

• What is the best temperature to make a sourdough starter?
  • It is possible to begin a sourdough starter in any environment. If it is hot, the fermentation process will likely be faster. If it is cold, the fermentation process will likely be slower – and may need some help from you.
    • To achieve the best results, you want your starter in a warm place. The ideal temperature to make a sourdough starter is between 75-80 degrees farenheight. If your home is not regularly this temperature, try placing the sourdough starter in the oven with the light on for an hour or two. Just make sure to place a note on the oven not to turn on the heat!
      • If you have a thermometer, allow the temperature of the oven to reach up to 80 degrees, then turn the light off and keep the door closed. The temperature will naturally fall, though the increase of temperature will help to kickstart the fermentation process.
    • It is a good idea not to place your sourdough starter in direct sunlight as temperatures can become too hot.
    • Additionally, you can wrap the mason jar in a towel to help create warmth.
    • Humidity can also increase the speed of how fast a sourdough starter is created. Humidity does not matter as much as temperature does. I would not recommend altering your humidity level.
    • If your home is over 80 degrees farenheight, consider feeding your starter with cold water and keeping it in a dimly lit area, such as a closet or cupboard where it is out of direct sunlight.
• What is a hooch?
  • Hooch is the light brown liquid (alcohol) which can occur when creating a sourdough starter. In general, the fermentation process can create a hooch. It can also indicate the starter needs to be fed. If you have a hooch on your sourdough starter, simply discard it without stirring it into the starter and feed the starter.
• Why is my sourdough starter not creating bubbles?
  • There are a few different factors which could cause bubbles not to begin. Ask yourself these questions before starting the entire process again.
    • Time – How long has it been since you fed your starter? Are you feeding your sourdough at a consistent time? Did you allow over 24 hours from the day one to allow the sourdough to ferment adequately before discarding and feeding? This is the easiest way to see if you have a healthy starter.
    • Temperature – What is the temperature in your home? Have you tried troubleshooting to ensure your start is in a warm spot which is not too hot or too cold?
    • Flour – What type of flour are you using to start and feed your sourdough starter? Are you using a bag of fresh flour?
• What should my sourdough starter smell like?
  • Sourdough starter should smell aromatic and like yeast. If it smells stinky, like socks or heavily of alcohol, you may want to consider starting again from the beginning. A sourdough starter is likely to smell like acetone for a few days as it gets more mature “aka hungry”. Continue to discard and feed regularly to encourage development.
• What if my sourdough starter has mold?
  • If your sourdough starter has white, black or pink colored mold, it is time to start fresh. Mold in one spot means mold throughout that you can not see with the bare eye. If at any time your jar becomes caked on the side with sourdough starter, feel free to move to another clean jar.
• Do you have to discard when creating a sourdough starter from scratch?
  • Yes, discarding while creating a sourdough starter is necessary. Because the sourdough starter is a fermentation process, it prefers a certain level of acidity to continue. This recipe is a sourdough starter recipe with minimal discard. We both know how expensive flour is – especially if this is not your first time creating a starter!
• Why do you switch from whole wheat flour to another flour when beginning a sourdough starter?
  • Whole wheat flour is one of the best flours to begin a sourdough starter with. It tends to have the best yeast to help jumpstart the fermentation process. You can continue to feed a sourdough starter whole wheat flour or switch to a different flour.
  • Other flours could include all purpose flour, whole grain flour, rye flour or bread flour. I find beginning with a whole wheat flour feeding from Day 1 and feedings for the next seven days allows it to ferment faster than using bread flour or all purpose flour.
• Why do some people use filtered water or bottled water to make sourdough?
  • Chlorine within city (tap) water can negatively impact a sourdough starter. If you do not have any other option but tap water – allow the water to sit out at room temperature for a few hours to allow the chlorine to dissipate. Because city water is often treated with chlorine, some people will opt for filtered or bottled water.
  • If you have a water filtration process for your drinking water, consider using this to begin a sourdough starter. Note, water temperature does not matter, though warm water (I.E. lukewarm to the touch), can produce faster fermentation results than ice cold water.
• How long does it take to make a sourdough starter?
  • The whole process can take anywhere from seven days to two weeks to develop a sourdough starter which is ready to be baked with. This time can vary depending on the temperature and humidity of your environment.
• Do you have to use organic flour?
  • Organic flour is recommended for sourdough starter, though it is not essential. Organic flour has not been exposed to any chemicals or toxins which provides the most nutrient dense starter.
• Can you use bleached flour?
  • Though it is not recommended to make a sourdough starter with bleached flour, it can work. The chemical process used to bleach flour can interfere with the fermentation process by removing some of the natural occurring bacteria and yeast found on flour. A popular brand of flour found in most major grocery stores is the King Arthur flour brand
• How much flour should you begin with to create a good sourdough starter?
  • If you are concerned because there are a variety of sourdough starter recipes saying you must begin with 1 cup of flour and 1 cup of water, that is simply not the case.
  • To create a happy starter, keep the ratios small. You really need minimal amounts of ingredients and can grow your starter as it becomes stronger and you need more for recipes. Our recipe starts with 1 ounce of flour to 1 ounce of water to limit waste.
    • If you need to give your sourdough starter a ‘boost’, try dry feeding the sourdough starter.
• How long can sourdough discard sit in a fridge?
  • If you fed your sourdough starter and are not going to utilize it right away in a recipe, consider pulling some aside and placing it within the fridge. Sourdough discard can sit for up to seven days within an airtight container before it needs to be utilized within a recipe or tossed.

Have you created a sourdough starter before? If not, what hurdles are preventing you from doing so? Share your sourdough starter experiences in the comments below!