Most home cooks would stock up sachets of yeast, hoping it would serve them indefinitely. This begs the question, “How long does baker’s yeast last?
Yeast is a commonly occurring micro-organism. Not only is it found in the human body as candida, yeast is also a popular ingredient in culinary arts, mainly used in baking, brewing and fermentation.
Common forms of baker’s yeast include active dry yeast, instant yeast and cake yeast.
In whichever form you purchase yours, being aware of the shelf life, favorable storage conditions as well as when to discard, comes in handy to guarantee effective yeast usage.
Read on to discover how long baker’s yeast lasts in addition to effective storage techniques that prolong its shelf life.
What is the Shelf Life of Baker’s Yeast?
The shelf life of yeast mostly depends on the prevailing storage conditions. Yeast has a “best by” date which is set from the date of packaging.
Using yeast after the best by date has transpired is dependent on your storage conditions.
How long does yeast last? (When opened)
Opened fresh or compressed yeast is best stored in the refrigerator, but not freezer.
Maintain it in its original package or transfer to an airtight seal-able bag.
When properly stored, compressed yeast will last up to 4 months.
Opened dry yeast can be stored in the pantry, refrigerator or freezer.
When kept in the fridge or freezer, ensure you enclose it in an airtight bag or container as the damp conditions can affect its potency.
When properly stored, dry yeast can last up to 6 months in the freezer and 4 months in the refrigerator.
The best by date should guide you when storing yeast in the pantry.
Avoid extending the use of yeast past its best by date since potency is most likely diminished.
How long does yeast last? (Unopened)
Favorable storage areas for unopened yeast are the pantry and refrigerator.
Unopened fresh yeast has a longer shelf life when stored in the refrigerator – it can last up to 3 months after the expiry date.
On the other hand, when stored in the pantry, unopened fresh yeast will last for a few weeks, 3 weeks at most.
Unopened dry yeast has a longer shelf life. If you live in a hot climatic region, utilize the refrigerator.
Dry yeast will keep well in the fridge for up to 4 months. Storing dry yeast in the pantry is favorable if you maintain effective storage techniques as described below.
When well stored, it can last for 3-4 months in the pantry.
How long does liquid yeast last?
Liquid yeast is popular in beer brewing although dry yeast can still be used in brewing.
Liquid yeast is however costlier, but it has a shorter shelf life. Store liquid yeast in the refrigerator.
Viability of liquid yeast can range from 4-6 months when properly stored in the fridge.
Even so, ensure you keep the packet sealed at all times in order to realize your shelf life goals.
4 Effective Yeast Storage Techniques for a Longer Shelf Life
Yeast storage revolves around temperature. However, there are other equally important factors to consider.
Here are 4 effective storage techniques for yeast.
- Airtight, seal-able containers
Use airtight containers for opened yeast. Air promotes loss of yeast effectiveness. Once you open any packet, store the remaining yeast in airtight containers.
- Cool, dry area
Yeast is best stored in a cool, dry place. Cool temperature prevents activation of yeast. A dry storage condition is also effective in mitigating spoilage.
Dry yeast keeps well in the pantry or kitchen cabinets. Compressed (fresh) yeast is best stored in the refrigerator, under a controlled temperature.
- Avoid direct sunlight
Since yeast is a living microorganism, certain factors can cause the yeast cells to die. Sunlight is one such factor.
Exposure to heat or sunlight also reduces the potency of yeast. Prolong the shelf life of yeast by avoiding direct sunlight and heat.
Don’t store yeast in a cabinet directly above the stove or cooking range.
- Exhaust each packet at a time
You can prolong the shelf life of yeast, or any food item by using portions. Yeast comes in sachets or full packets.
Avoid buying large packets if you don’t intend to use frequently. Buying and using what you need at a time minimizes wastage.
It also guarantees usage of fresh ingredients, hence great baking/brewing results.
Yeast Effectiveness Test to Determine Potency
You may have stumbled upon a packet of yeast hiding in your pantry. You can’t even recall when you bought it.
Before discarding the yeast, conduct this quick experiment to rule out any lingering doubts on its potency.
Dissolve a sachet of yeast in ¼ cup of lukewarm liquid – use plain water. Add a teaspoon of sugar and stir well. Yeast feeds on sugar, hence its addition is perfect for testing the potency.
Leave the mixture at room temperature for several minutes.
For positive results, the mixture should froth, become foamy and rise after several minutes.
If the yeast has lost potency, expect the mixture to remain flat, without any foam.
Tell-tale Signs of Spoiled Baker’s Yeast – Fresh or Dry
Yeast is a living micro-organism and will disintegrate and lose potency at some point. How can you then identify unusable yeast?
Spoiled dry yeast tends to have similar characteristics as those of any other dry food items like powdered spices or flour.
Clumping and chunk formation in the yeast is a sign of spoilage.
Discoloration is also a clear indicator of expiration. Yeast has a beige, ivory hue to it, hence any changes to a darker hue should be alarming.
Moldy growth is a sign of spoilage. This is more prevalent on fresh or compressed yeast due to moisture content. Discard such yeast immediately.
Watery texture on compressed yeast indicates rot. Do away with the yeast.
For any avid baker or brewer, yeast is considered a monumental ingredient. Its inclusion is the Midas touch which transforms bread, pizza dough, croissant, beer, lager or ale into gold. As such, it is imperative to know how long yeast lasts to utilize it to the fullest.