3 Best Ways to Make Thicker Jam or Jelly


Many jelly and jam lovers prefer their spreadable preserves to be a little softer or even runny so that it spreads easier on a peanut butter sandwich. However, some like them more solid or thick. As a professional jelly maker and a devoted member of the second group, I have been experimenting for several years now on making jelly that sets quickly and firmly.

How to have thicker jam or jelly:

  1. Cook it longer than called for.
  2. Add more pectin to each batch.
  3. Incorporate both methods by cooking each batch longer and adding extra pectin.

All of these methods are easy to do and result in a firm product that begins to gel long before it is cool. Personally, I almost always use method number three. By the time the jelly is completely cool, it will be set completely. That typically takes about 45 minutes to an hour.

Let’s take a look at each of these methods more closely.

Method 1: Cook the Jelly Longer

The standard recipe for making jelly which can be found in the instructions in the fruit pectin boxes, instructs you to boil the jelly for one minute and process it in the boiling water bath for five minutes. By this process, quite often it is the next day after the jelly has cooled entirely and has sat, untouched, for 24 or so hours, before it sets completely, and then it is usually a set that is not too firm and is spreadable and even sometimes a bit runny.

My recipe, which was passed down to me by my mother and to her by her mother (you get the picture), instructs you to allow the jelly to cook for 7-9 minutes. This way, I am able to eliminate the step of the boiling water bath as the jars and lids have been sterilized by boiling while the jelly is being cooked. And by cooking the jelly for 9 minutes, it is much firmer than the boiling water bath method, and overcooking is not a concern.

Also, when the jelly is poured into the jelly jars, the jelly is still at the boiling point, the jars are sitting in boiling water, and the lids are sitting in water that has been boiled and is still hot. So, everything is sterilized, fully cooked, and sealed securely so that it is completely safe for my family’s use. With this method, it is rare for any of the lids to fail to seal properly.

By cooking my jelly and jams longer, they usually set within an hour.

cooking jam timer

Cooking Adjustment When Making Jams

For jam, It is too difficult to cook the jam for a more extended period because of the risk of scorching or burning and because the juice is likely to evaporate and leave the jam too dry. Therefore, I cook for 3 minutes and use the boiling water bath method for 10 minutes.

Method 2: Add More Pectin

The second way of getting a firmer set is by adding a little more pectin. Using one package of boxed pectin will most of the time give you jelly that is set well with just a little jiggle to it. I used one box of pectin per batch for many years and got a more firm result by cooking each batch longer, as discussed in Method Number One. Several people I know use a box and a half of pre-packaged pectin per batch to get a firmer jelly.

However, after I started making many batches of jelly at the time, I discovered it was much more cost-effective to use bulk pectin for jelly and jam, and gave me the choice to decide how much to use per batch rather than being limited to the amount packaged in each box. By the way, I wrote an article on what I think the best pectin brands are, be sure to check it out.

The amount of bulk pectin that the manufacturer recommends to use per batch is three tablespoons. However, I always use 4 tablespoons of pectin per batch as I like my jelly to be more firm and to set more quickly.

Method number two is to either use 4 tablespoons of bulk fruit pectin or one and one-half boxes of the pre-packaged fruit pectin.

Sure-Jell Fruit Pectin Box

Method 3: Cook Longer and Add More Pectin

Combine Methods One and Two: Use 4 tablespoons of bulk fruit pectin or one and one-half boxes of pre-packaged fruit pectin and cook each batch of jelly for 9 minutes, omitting the boiling water bath method. This should give you a very firm jelly with the shortest possible set time.

What to Do If Your Jelly or Jam Doesn’t Set Properly

Occasionally, it seems that no matter what you do, at least one batch will not set properly.

Did you ever have this happen? You just made six batches of blackberry jelly, and it is beautiful! But, for some unknown reason, when you check it a couple of hours later, all the jars have set except for the jars from one batch. So, you say, maybe by tomorrow morning it will have set…, but no dice! When tomorrow morning comes, those jars still have the consistency of half-set jello.

How could this happen?

  • You count the empty pectin boxes to make sure there are 6…check!
  • Maybe you didn’t put in the right amount of sugar, but, no, you distinctly remember triple measuring sugar for all six batches before you started making the jelly…check!
  • Maybe you didn’t cook it enough. But how could that happen when you set the timer for each batch…check!

The question is, what made the one batch refuse to set correctly? That is just one of life’s little mysteries, and we may never know the answer.

When you have jelly that doesn’t set, here’s what you do:

  1. Start the process by placing jars that have been washed in hot, soapy water and rinsed well in a pan of water. Bring the water to the boiling point and allow them to boil for the entire time the jam is cooking.
  2. Bring another pan of water to a boil, then reduce heat to simmering and place lids in that water until needed.
  3. Open all the jars.
  4. Pour the jelly back into the pot.
  5. Add another half box of pectin (or 2 tablespoons of bulk pectin).
  6. Cook for 2-3 minutes more. 
  7. At that point, turn off the burner, remove any foam from the top of the jelly, and pour it into prepared jars.
  8. Wipe the jar rims with a clean damp cloth before affixing lids to ensure there is nothing on the rims to prevent a good seal.
  9. Affix lids that have also been in hot water for at least ten minutes.
  10. Move jars to the prepared surface where they will sit, unmoved, until completely cool.

Can I Reuse the Lids?

It is usually alright to reuse your jam or jelly jar lids, but I do not recommend it. However, if you are making the jelly for your own use, go ahead and reuse the lids as you can always immediately refrigerate any jars that do not seal properly and use those jars first.

Ways to Make Sure That Jelly and Jams Set Correctly

1. Measure Exactly

One of the best ways to make sure jelly sets properly every time is always to measure precisely. Making jelly that sets properly has to contain the proper ratio of fruit/juice to sugar to pectin. Follow your recipe and measure all ingredients precisely. The recipes provided by the pectin makers are tried and true, and you can depend on them.

 I have a particular set of measuring cups that I use for all jelly making, and I use the same cup for juice and sugar. Many measuring cups make it challenging to get an exact measurement, so I use one that I fill all the way to the top so that all ingredients are measured the same.

2. Use a Timer

It is very difficult to get the same results with every batch of jelly if you don’t cook them the same length of time. Using a timer is the best way to achieve that goal. I used to watch the clock and try to get the time right, but quite often, either my mind would wander, the phone would ring, or something else would distract me from my task, and I wouldn’t be able to remember just how long I had cooked that jelly! It’s much easier now as most stoves have a built-in timer, or you could use the timer on your phone or watch. Even most microwaves have a timer these days.

3. Let It Set For 24 Hours

When your jars of jelly are finished and you put them on a towel to cool, be sure you leave them untouched for about 24 hours, so you don’t disturb the way they set. I know it is hard to keep from picking them up to see how they look, but you get a faster and firmer set if you let them sit untouched until the next day.

Small batch of jelly

Can I Use Tapioca as a Thickening Agent?

We all know that fruit pectin is the most widely used thickening agent used in jam and jelly, but I’m sure some of you have wondered, as have I, whether tapioca could be used instead of the pectin.

Tapioca can be used as a thickening agent. It is a natural substance that absorbs liquid and thickens and gels. It is a healthy and flavorless replacement for other types of thickeners.

Here is a good recipe to use when you try the tapioca as a thickener for Jam:

A Quick Recipe for Homemade Refrigerator Jam Using Tapioca as a Thickening Agent

  • 2 cups prepared Strawberries (washed, trimmed, and chopped)
  • 1/2 cup Honey
  • 1 teaspoon Lemon Juice
  • 1 package Fruit Pectin or 2 tablespoons Chia Seeds or 2 tablespoons Tapioca or 2 tablespoons Cornstarch
  1. Place strawberries, lemon juice, and tapioca in a Dutch oven or other pot (not aluminum), and bring to a boil.
  2. Add honey and return to a boil, boiling for 2 minutes, stirring frequently.
  3. Reduce heat, and cook over medium heat for 10 minutes, stirring frequently and skimming off foam. Use a potato masher to mash the fruit while it is cooking.
  4. Pour into prepared jars, wipe jar rims and affix lids, and set on a towel to cool.
  5. Once the jam has cooled completely, place in the refrigerator, ready to use.

Once the jam is made, it will keep for at least 6 months in the refrigerator or for a year in the freezer. Any alternative sweetener can be substituted for honey, and the amount of sweetener can be adjusted to taste. Chia seeds or fruit pectin can be substituted for the tapioca to thicken the jam, or this recipe can be made without a thickener by cooking it for an additional 10 minutes. Don’t use gelatin or jello to thicken the jam if you are going to store it in the freezer as the liquid would begin to separate when thawed.

Can I Use Cornstarch as a Thickening Agent?

Cornstarch can be used as a thickening agent. It is a natural thickener as it is a product of corn.

This is a product that most of us have in our cabinets on a regular basis and could be used as a substitute for the pectin in the recipe listed above for homemade refrigerator jam. Use 2 tablespoons of cornstarch as a thickener in this recipe.

Jello and Gelatin can be used as a thickener as well, click here to read more.

jello gelatin boxes

Final Thoughts

If you are a serious jelly maker and would like to fine-tune your jelly-making process, I would recommend following all of these tips of making jelly set firmer and faster:

  • Cooking longer.
  • Adding more pectin.
  • Measuring precisely.
  • Using a timer.
  • Giving them about 24 hours to cool and set.

Give it a try and see what you think. Bet you’ll love it, and you’ll get rave reviews from your family!

Anne James

Hi, I'm Anne but my grandchildren call me Jelly Grandma. I have over 50 years of experience as a Southern cook and am a retired librarian. I love sharing what I have learned. You can find me on YouTube as well! Just click the link at the bottom of your page. I hope your visit here has been a sweet one.

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