Sugar-free jams and marmalades

Today’s home canners want to make jams that are as good for you as they taste: they are looking to make wholesome, nutritious jams that aren’t going to cause teeth to rot in your head and pack on the weight — which is the last thing most of us need!

Most jam recipes from all the tested, reliable sources require you to add anywhere from 5 to 9 cups (1 to 1.8 kg) of sugar per batch, for just a few jars! One jam recipe promoted by Ball in 2015 on their Facebook page, carrot jam, calls for 8 ½ oz. of sugar per 8 oz. jar of jam being made.

It’s important to recognize that jams and jelly are candy. You are essentially candying the fruit to preserve it,” explained Sherri Brooks Vinton, author of the best-selling “Put ’em Up” canning books and “Put ’em Up Preserving Answer Book: 399 Solutions to Your Questions.” ^[1]Andrea Weigl, Canning 101: Making the most of fruits and veggies.  Raleigh, N.C.: The News & Observer. 21 July 2016. https://www.detroitnews.com/story/life/food/2016/07/21/canning-making-fruits-veggies/87352934/

Let’s face it: you’re basically making fruit-flavoured sugar, and while old-time canners may be used to that, many modern canners are shocked by it and just don’t regard it as acceptable any longer.

On this page, we’re going to examine the topic of making sugar-free fruit spreads such as jams, jellies and marmalades.

Note: the real challenge in finding something to use instead always boils down to the bottom line of people’s individual tastes. No matter how well something performs, you will never please everyone’s taste buds, and it’s a fool’s game to try. You will always find someone who curls up their nose at the taste of something. That may be part of the reason big companies such as Ball continue promoting the heavy use of sugar: it’s the path of least resistance.

Types of fruit spreads

• Jelly: firm gel from juice;
• Jam: sweet softer spread made from crushed fruit;
• Preserve: whole fruit pieces of uniform size;
• Conserve: nuts, 2 or more fruits, raisins, coconut;
• Marmalade: citrus added, including citrus peel or rind.

Other fruit concentrates:

• Fruit butter: cooked fruit spread from fruit pulp;
• Fruit honey: consistency of honey from fruit juice;
• Fruit syrup: sweet, thickened fruit juice.

Sugar’s role in fruit gels

Fruit products that rely on pectin (either natural or added) for their characteristics are also referred to in the field as “gels.”  ^[2]  Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 1:18:08. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

Sugar will make jams and jellies set hard because, with the quantities of sugar traditionally called for, they are essentially candy.

Some people point out that adding tons of refined sugar to get a set on jam is, in fact, a very modern way of making jam, as the sugar wasn’t available and when it was, it was an extreme luxury; that the true traditional way of getting a set in jam was boiling and boiling it till it set naturally, though that would have been a softer set, certainly.

Sugar’s preservative effect is to, in effect, sort of mummify the fruit.

Thickening fruit spreads

Fruit spreads can be thickened by:  ^[3] Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 43:00. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

1. boiling them down and naturally concentrating the pectin;
2. using added sugar and added pectin;
3. using no-sugar needed pectin.

“By doing this concentrating or thickening through one method or another, we are making water less available to the micro-organisms, so they are not going to be able to multiply and cause as many problems as they would in foods with a lot more available water.”  ^[4] Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 43:41. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

The role of acidity in fruit spreads

Most fruits are acidic, which makes them safe for canning in a boiling water bath. (There are only a few low-acid fruits which are not: such as melons, figs and rambutan.)

It is not safe to make preserves from these unless you have a tested recipe. A method was developed for safely canning figs by adding acidity to them.

Melons are fruit that most people don’t realize are low-acid.

Unless a jelly or jam recipe using melon takes special precautions to ensure sufficient added acidity, the resulting product can be unsafe. People have contracted severe cases of botulism from melon jam recipes that weren’t lab-tested for safety because the low-acid nature of the finished product allowed the botulism toxin to develop in the sealed jar.

The University of Wisconsin gave this advice in 2013:

Most fruits – peaches, pears, apples, and oranges are good examples – are high in acid, they have a pH of 4.6 or below. Melons (honey dew, watermelon, and cantaloupe) are an exception to this. Melons have an average pH of 6.2, they are low in acid.  Because these fruits are low in acid, they can not be safely canned in a boiling water canner unless the product is significantly changed by adding a lot of acid or sugar. The amount of acid added to jams and jellies to help pectin to gel is not enough to ensure the safety of watermelon jelly. And no tests have been done to indicate just how much sugar would be needed for a safe jelly.”  ^[5] Ingham, Barb. Safe Preserving: Watermelon Jelly. In: Safe and Healthy: Preserving Food at Home. University of Wisconsin-Extension Cooperative Extension. 30 August 2013. Accessed January 2015 at: https://fyi.uwex.edu/safepreserving/2013/08/30/safe-preserving-watermelon-jelly/.

Since then, Ball and Bernardin have released some lab-tested recipes. One is Melon Jam in the Ball All New. Another is Bernardin’s Zesty Watermelon Jelly. (Here is a full list of all types of home-canned products using melon .)

Tested, safe spread recipes for low-acid foods will have had enough acid added to make them safe:

You may see some tested recipes for savoury spreads or jellies being made with low acid items such as onion and pepper. Those recipes will call for [Ed: classic aka “high methoxyl”] pectin, and acids such as lemon juice, vinegar, apple juice, etc.  The acid both makes the product safe food safety-wise, and, helps with the set because the [Ed: classic] pectin molecule “will not gel above a pH of 4.6. it’s actually quite a bit lower than that.”  ^[6] Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 44:00. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

The environment has to be acidic for the pectin to even work.

Note that it’s not usually the sugar that makes the jam or jelly safe, but rather the acidity levels. While truly extreme concentrations of sugar can prevent indeed prevent the botulism toxin from developing by reducing water activity (taking water away that botulism bacteria would need to do anything), the fact is almost no home canning recipes call for enough sugar for the sugar content to do that. Instead, acidity is relied on. In fact, many commercial packaged pectin mixes contain added citric acid, which helps improve the safety of the product being made with it.

Four ways to make sugar-free jams

The National Center for Home Food Preservation did a blog posting in August 2014, listing 4 ways to make sugar-free jams  ^[7] Christian, Kacey. National Center for Home Food Preservation. Want to Make Sweet Spreads, but Don’t Want to Add Sugar? 1 August 2014. Accessed June 2015 at https://preservingfoodathome.com/2014/08/01/want-to-make-sweet-spreads-but-dont-want-to-add-sugar/ .

Their concern in this blog posting is how to get acceptable quality from sugar-free fruit preserves.

Use Specially Modified Pectin

Specially modified pectin, (aka low methoxyl pectin) is sold labelled as “light” or “no sugar needed” pectin. Recipes on leaflets accompanying the products will usually give the options of using a little sugar, or none at all. Those leaflets, however, from the big-name makers such as Ball, Bernardin or Sure-Jell, offer only a small, limited handful of recipes. Other no-sugar needed pectins, such as Pomona, have recipe books and whole recipe websites dedicated to them, offering the user a substantially wider range of recipes to choose from.

Healthycanning.com would just add the precaution that some of these new modified pectins can gel anything — even plain water. That can be a danger. First, bear in mind that the safe pH range for shelf-stable fruit preserves is 4.6 and lower. Older, traditional pectins would only gel if the product was in a narrow pH range (between approximately 2.8 and 3.6.), which coincidentally also happened to be low enough to ensure the safety of the product. The new ones can gel in a pH up to 7, which is way above the safety cut-off of 4.6. Consequently, this is yet another reason to make sure you are using only tested recipes (which will have a safe pH range either naturally from the fruits or from added acidity such as bottled lemon juice) when using these new pectins. You don’t want to be serving up botulism spread to have with toast and tea.

Here’s a brief video overview of no-sugar-needed pectins . The main speaker is Dr Martha Zepp from PennState Extension.

Use Regular Pectin With Special Recipes

Occasionally you may find recipes calling for regular pectin and reduced or no sugar, but these are rare. Someone will have probably gone to a lot of (expensive) trial and error attempts to get a recipe that works. Better them than you.

Long Boil

A long boil-down of the fruit, to produce a fruit spread, is a method that has been used for centuries (pectin as an add-in commercial product is very recent in human history.)

Such spreads, once put in jars, usually also require a longer water bath processing time, to make up for the lack of added pectin which would otherwise be depriving micro organisms of water — so you need to make sure that you are actually killing those micro organisms off. Consequently, in general, unless otherwise specified, use processing times for water-bath canning that treat as a fruit (rather than as a jam.)  ^[8] Stone, Martha and Mary Schroeder. Current Issues in Food Preservation: Desktop Training Powerpoint Slide Show. Colorado State University Cooperative Extension. 21 June 2006. Slide 13. Accessed March 2015 at https://www.authorstream.com/Presentation/Laurie-31729-Current-Issues-Food-Preservation-6-21-06-Overview-Jams-Jellies-Traditional-Ingredients-Pectin-Acid-Pr-as-Entertainment-ppt-powerpoint/

That being said, the long-boil method is probably not going to be satisfactory for most people with today’s expectations of what a jam should be like. The jam can become gummy and caramelly tasting. Some varieties of fruit may perform slightly better than others: some have suggested that, for instance, small cultivars of strawberries such as Alpine are better in a long boil jam than larger cultivars such as Driscolls. They also suggest that a quartered green apple added and then removed before canning may add some pectin.  ^[9] Blog discussion at https://dinersjournal.blogs.nytimes.com/2009/06/01/preserving-memories/#more-3693. Accessed June 2015.

Use Gelatin

You can use gelatin as a thickener in fruit spreads, but for refrigerator jams only, not for shelf-stable canning. Refrigerate and use within four weeks (or freeze.)

Using Clearjel in jams

In comments following a National Center for Home Food Preservation blog posting of August 2014  ^[10] Christian, Kacey. National Center for Home Food Preservation. Want to Make Sweet Spreads, but Don’t Want to Add Sugar? 1 August 2014. Accessed June 2015 at https://preservingfoodathome.com/2014/08/01/want-to-make-sweet-spreads-but-dont-want-to-add-sugar/ , the Center’s representative says, “Modified corn starch (like Clearjel) does not depend on the same concentration of sugar to form a gel, if any added sugar at all with some fruits, so it makes sense to use in low-to-no sugar recipes.”

They add, though, “However, we do not know of tested recipes using Clearjel for making canned low-to-no-sugar jams and jellies, and have not developed any ourselves, so we are unable to make specific recommendations for its use at this time.” [Ed: Washington State Extension actually released tested Clearjel jam recipes in October 2007.]

The NCHFP give some tips as to what kind of development testing would be needed: “Since the spread would not have sugar to aid in its preservation, it may require a slightly longer than usual process time for long-term room temperature storage. These products could very well be thickened fruit purees and will not fit the definition of a pectin jam or jelly, even though it produces a spreadable, gel-like consistency.”  ^[11] National Center for Home Food Preservation Blog. Want to Make Sweet Spreads, but Don’t Want to Add Sugar? 1 August 2014. Accessed March 2015 at https://preservingfoodathome.com/2014/08/01/want-to-make-sweet-spreads-but-dont-want-to-add-sugar/

Utah State Extension Service feels that a modified starch product (which Clearjel is) could be used in fruit spreads. (The advice below was written in 1992; when they mention saccharin, remember that the choices for alternative sweeteners were very limited at that time.)

Modified starch products can also be used to thicken jams with reduced sugar content. Directions indicate that a small amount of sugar used in the preparation will improve flavor, color and texture. However, for a sugar-free diet, use of saccharin only gives an acceptable product.”  ^[12] Lauritzen, Georgia C. Reduced Sugar and Sugar-free Food Preservation. Utah State Extension Service. 1992. FN 209. Page 9. Accessed June 2015 at https://extension.usu.edu/files/publications/publication/FN_209.pdf

In any event, all that being said, Washington State Extension Service has actually gone ahead and developed and released jam recipes using Clearjel.

Please note that while these jams are supported by the Extension, they are not currently (2017) promoted / supported by the National Center.

In this 2017 video, Dr Martha Zepp from PennState Extension says not to use Clearjel in jams:

Alternative sweeteners for sugar-free jams

The following applies to recipes that don’t depend on the addition of refined white sugar for the gelling of the fruit spread to happen. These sweeteners won’t perform well if that is a requirement for a particular jam recipe.

1. Stevia

Stevia is a natural product derived from a plant, just as sugar is. Less pure forms of it can have aftertastes including bitterness– just as raw sugar cane can.  Purified forms of stevia (such as the liquid concentrate made by Better Stevia) do not.

None of the public sector bodies (NCHFP, USDA, University Extensions) have publicized yet any work they might have done with it. The University of Kentucky and Penn State seem to be saying that they don’t foresee any problems with it and appear to give a nod towards its use as a sweetener in canning.

Stevia is stable to heat and could be used for canning fruit and other products where sugar is not critical to food safety or texture.” ^[13] Penn State Extension. Sugars and Non-Nutritive Sweeteners in Food Preservation. 1 July 2012. Accesssed January 2015 at https://extension.psu.edu/food/preservation/news/2012/sugars-and-non-nutritive-sweeteners-in-food-preservation

In the private sector, none of the Jarden recipe sources (Ball or Bernardin ) have released any recommendations for it yet one way or the other — but, with respect, some of their recipe writers are very yesteryear at times and as such are heavily reliant on massive amounts of sugar and salt, and appear unaware of, or impatient with, or resistant to the changing market. But the more progressive people over at Pomona pectin do give guidelines for jams with concentrated (liquid) stevia.

HealthyCanning.com has chosen concentrated, liquid stevia as its sweetener. It’s easy to use, calorie-free, has a pure clean sweet taste with no aftertaste, and appears to provide quality results.

We use it as the sweetener in jams and jellies made with no-sugar needed pectin, either Jarden Brand (Ball or Bernardin) or Pomona, using tested recipes from from those companies. In such recipes, where any sweetener at all is optional, liquid stevia is ideal as there is no danger of it affecting the texture or composition of the recipe, while still providing satisfying sweetness.

2. Splenda

Splenda® (aka sucralose) provides sweetness. The NCHFP has used it in a few recipes. (Note, however, that some forms of sucralose, which contain bulking agents such as maltodextrin, are not actually calorie-free.)

“You could use Splenda® as the optional sweetener in a jam or jelly made with a no-sugar needed pectin, such as Mrs. Wages™ Lite Home Jell® Fruit Pectin or Ball® No-Sugar Needed Pectin. With these low-methoxyl pectins, no sugar is required at all. Sugar substitutes can be added as desired simply for flavor. The package inserts with these pectins give instructions on when to add the sugar substitutes (usually after all the cooking, right before filling the jars). We have not yet tried Splenda® with these pectins with an extensive variety of fruits, however.”  ^[14] Penn State Extension.   Can Splenda (sucralose) be used in preserving food?  Accessed January 2015 at https://extension.psu.edu/food/preservation/faq/splenda

3. Aspartame

Aspartame is not recommended for a quality reason, which is simply that its sweetness is destroyed by heat:

“…aspartame may lose its sweet flavor within 3 to 4 weeks.”  ^[15] Christian, Kacey. National Center for Home Food Preservation. Want to Make Sweet Spreads, but Don’t Want to Add Sugar? 1 August 2014. Accessed June 2015 at https://preservingfoodathome.com/2014/08/01/want-to-make-sweet-spreads-but-dont-want-to-add-sugar/

“… aspartame loses the sweet flavor when heated.”  ^[16] Lauritzen, Georgia C. Reduced Sugar and Sugar-free Food Preservation. Utah State Extension Service. 1992. FN 209. Page 4. Accessed June 2015 at https://extension.usu.edu/files/publications/publication/FN_209.pdf

4. Saccharin

Saccharin is not recommended for taste reasons.

“Saccharin can produce an unwanted aftertaste….”  ^[17] Lauritzen, Georgia C. Reduced Sugar and Sugar-free Food Preservation. Utah State Extension Service. 1992. FN 209. Page 4. Accessed June 2015 at https://extension.usu.edu/files/publications/publication/FN_209.pdf

“Saccharin-based sweeteners such as Sweet’N Low, Sugar Twin, or Sweet 10 become bitter when exposed to canning temperatures…”  ^[18] Penn State Extension. Canning With Artificial Sweeteners . Accessed January 2015 at https://extension.psu.edu/food/preservation/faq/canning-with-artificial-sweeteners

4. Honey

Pomona pectin allows for the use of honey in many of its recipes, without any adjustments to the rest of the recipe being required. It may affect colour slightly depending on what you are making and how darkly-coloured your honey is. Note, however, that honey is pH neutral. It will impact the acidity of what you are making, sometimes lowering it.

5. Sweet One

William C. Morris, Associate Professor of Food Science and Technology with the University of Tennessee Agricultural Extension Service, published this information in 2004: ^[19]Morris, William C. Low or No Sugar in Jams, Jellies and Preserves. University of Tennessee Agricultural Extension Service. SP325F(Rev.)-1.5M-5/04 . 2004. Page 1. Accessed August 2017 at https://extension.tennessee.edu/publications/Documents/SP325-F.pdf

• “Sweet One”- acesulfame-k, is heat stable;
• 12 packets of Sweet One = 1 cup sugar

We haven’t worked with this, or seen anything else about it (as of 2017), we are just passing it on for other people researching the topic.

Jar size

There appear to be two reasons not to use jars larger than are specified in your jam recipe. The first is easy to guess at:

1. Longer processing times would be needed for proper heat penetration, and you have no way of knowing exactly what it would be.

The second is a quality reason and may be less obvious:

2. “Use of larger jars may result in excessively soft products.”  ^[20] Garden-Robinson, Julie. Jams and Jellies from Native (Wild) Fruits. North Dakota State University Extension Service. January 2015. FN1423 . Accessed March 2015 at https://www.ag.ndsu.edu/pubs/yf/foods/fn1423.pdf

Smaller jars than called for would appear to always be fine.

Canning the jams: head space

The standard head space for jellies and jams is ½ cm (¼ inch). This applies regardless of the size of jar you pack the jam into, and whether the jam is sugar-free or sugar-laden.

Canning the jams: processing times

Summary: reduced or sugar-free jams may require a longer processing time than sugar-bloated ones. This is because instead of neutralizing micro organisms with sugar, you need to kill them outright with heat. But this is not a worry, because the tested no-sugar needed pectin recipes you use will already be giving the correct, adjusted processing time (just remember to always do any additional adjustment necessary for your altitude.)

Because these contain less sugar than regular jams and jellies, they are more susceptible to mold growth. Reduced-sugar jams and jellies may require longer processing in the water bath canner to kill these micro-organisms that might cause spoilage.”  ^[21] Morris, William C. Low or No Sugar in Jams, Jellies and Preserves. The University of Tennessee Agricultural Extension Service. SP325-F. https://ag.tennessee.edu/foodscience/Documents/Low%20or%20no%20sugar%20in%20jams,%20jellies%20and%20preserves.pdf

USDA recommended processing times for jams and jellies were developed based on sugar and added pectin products — not on simple pure concentrates of fruit pulp or juice. Without the added pectin, there might be more water available to micro organisms that could cause spoilage:

A 5 or 10 minute process [Ed: which is sufficient] for gelled products may not provide sufficient sterilization for pulp products.”  ^[22]Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 1:18:08. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

But that’s not a problem, because they do have you covered anyway with an alternative processing time:

We do have directions for pureed fruit in the USDA canning guide that is a 15 minute boiling water process for acid fruits and people that aren’t actually getting pectin gels might be actually be better off using that with their own concentrated fruit pulp instead of a gelled product [Ed: instead of a processing time designed for a gelled product].”  ^[23]Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. 1:19:12. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

The NCHFP gives a tip about how a Clearjel based jam might have to be processed, “Since the spread would not have sugar to aid in its preservation, it may require a slightly longer than usual process time for long-term room temperature storage. These products could very well be thickened fruit purees and will not fit the definition of a pectin jam or jelly, even though it produces a spreadable, gel-like consistency.”  ^[24]National Center for Home Food Preservation Blog. Want to Make Sweet Spreads, but Don’t Want to Add Sugar? 1 August 2014. Accessed March 2015 at https://preservingfoodathome.com/2014/08/01/want-to-make-sweet-spreads-but-dont-want-to-add-sugar/ (So, as a fruit purée, it appears from the para above, that that might be a 15 minute processing time.)

In summary, it appears it may be important to process reduced or sugar-free jams and fruit spreads longer than high sugar ones.

“To prevent spoilage, process jars of low-sugar jams and jellies longer in a boiling water-bath canner than regular jams or jellies. Carefully follow recipes and processing times provided with each modified pectin product.”   ^[25] Kendall, Patricia. Canning Fruits. Colarado State University Extension. No. 9.347. June 2013. Accessed March 2015 at https://www.ext.colostate.edu/pubs/foodnut/09347.html

The problem with under-processing a high acid food, from a botulism standpoint, is that there are certain molds which can, if they take hold in your preserve, actually change the pH so that your formerly safe high acid preserve becomes low acid. Low acid means risk of botulism spores germinating, and we are back to a potentially dangerous product. The chance of this happening in a high sugar, high acid preserve is very remote, but more likely in the lower-sugar jams I tend to make. Processing in a bwb canner for the full time recommended in a tested recipe insures that mold spores and other bacteria that might be in the jar before processing are destroyed.”  ^[26]Strauss, Eric. Blogger. Comment dated 26 August 2013, at https://www.nwedible.com/2013/07/how-not-to-die-from-botulism-what-home-canners-need-to-know-about-the-worlds-most-deadly-toxin.html#comment-64805 . Accessed June 2015.

This means that if you’re doing low-sugar jams, then it’s even more important to use modern processing recommendations. But that’s not a problem, or hard to do, because the tested recipe that you are using, from a reputable source, will give the correct processing time for your low-sugar jam, anyway! Sometimes you may find it’s the same as for similar high-sugar jams — but that’s fine, because their testing lab will have figured it out.

Finally, in terms of processing, all reputable sources agree on the following for your jams, whether they are sugar-laden or sugar-free:

1. To be safely shelf-stable, all home canned jam products in jars must be water bath processed for a tested, proven amount of time;
2. Do not use paraffin wax as a sealer, or single-piece lids, or clip-top hinge lids, etc.
3. Do not turn jars upside down after processing.

What about the 5 minute processing question?

It’s highly doubtful that any reduced or sugar-free jam recipe would call for a 5 minute processing time. We’ve seen above, required processing times tend to  longer for these products. But we’ll cover it here anyway as this is the jam page.

Some older jam and jelly recipes call for only a 5 minute water bath processing time (that’s at sea level — higher altitudes always adjusted accordingly, of course.)

A University of Nebraska extension rep, Julie Garden-Robinson, says:

Use sterile jars and a five-minute process time whenever possible….. The additional processing time may cause weak gels in some products…. Do not overcook. Overcooking may break down pectin and prevent proper gelling.”  ^[27] Garden-Robinson, Julie. Jams and Jellies from Native (Wild) Fruits. North Dakota State University Extension Service. January 2015. FN1423 . Accessed March 2015 at https://www.ag.ndsu.edu/pubs/yf/foods/fn1423.pdf

In recent years, Jarden’s companies (Ball and Bernardin) have said that any fruit product water bathed for 10 minutes or more does not needs its jar and lid sterilized. Consequently they are recommending increasing the 5 minute processing time, where still called for, to be increased to 10 minutes, and are adjusting their recipe directions to be a minimum 10 minute processing time. They disagree with what the University of Nebraska extension rep says above, and say that they detect no change in quality:

Heat processing time recommendations for jams and jellies was increased from 5 minutes to 10 minutes in 2003, thus eliminating the need to pre-sterilize mason jars before filling. Tests have shown that increasing the processing time does not adversely affect the product.”  ^[28] Bernardin FAQ. Accessed June 2015 at https://www.bernardin.ca/pages/faq/33.php#19

The extra 5 minutes may be more of a concern if you are trying to avoid using added pectin and relying on the natural pectin in the fruit only. Yet another University of Nebraska rep says,

Use of sterile jars is preferred [Ed: rather than the extra 5 minutes], especially when fruits are low in pectin, since the added five-minute process time may cause weaker jels.” ^[29] Albrecht, Julie A. Let’s Preserve: Jams, Jellies, and Preserves. University of Nebraska Lincoln Extension. EC448. August 2010 Revision. Page 4. Accessed March 2015 at https://ianrpubs.unl.edu/live/ec448/build/ec448.pdf

Storage life of sugar-free jams

There are a few storage issues to be aware of. They aren’t show-stoppers, but it’s good to just be aware of them.

1. Reduced or sugar-free jams may be more susceptible to mould growth

William Morris, Extension Agent at the University of Tennessee, writes:

Because these contain less sugar than regular jams and jellies, they are more susceptible to mold growth. Reduced-sugar jams and jellies may require longer processing in the water bath canner to kill these micro-organisms that might cause spoilage.”  ^[30]Morris, William C. Low or No Sugar in Jams, Jellies and Preserves. The University of Tennessee Agricultural Extension Service. SP325-F. https://ag.tennessee.edu/foodscience/Documents/Low%20or%20no%20sugar%20in%20jams,%20jellies%20and%20preserves.pdf

But as Morris points out, and as we saw in the section above on processing times, this issue is dealt with by longer processing times in the water bath, which your tested recipe from a trusted source will already have provided you with. As well, no-sugar needed pectins from Kraft® (Sure-Jell® ), Mrs Wages® (Lite Fruit Pectin) and Jarden (Ball® and Bernardin®) also may have preservatives added to them to help out.

These ‘lite’ or nosugar pectins usually have mold inhibitors added in the form of potassium sorbate, potassium benzoate or sodium benzoate.”  ^[31] Morris, William C. Low or No Sugar in Jams, Jellies and Preserves. The University of Tennessee Agricultural Extension Service. SP325-F. https://ag.tennessee.edu/foodscience/Documents/Low%20or%20no%20sugar%20in%20jams,%20jellies%20and%20preserves.pdf [Ed: Pomona pectin does not.]

In consolation, though, note that those sugar-laden jams aren’t safe from mould concerns, either: “Despite the high-acid content of fruit and the large quantities of sugar that are used to make jellied products, mold growth often occurs on the top.”  ^[32] Boyer, Renee R. and Julie McKinney. Boiling Water Bath Canning: Including Jams, Jellies, and Pickled Products. Virginia Cooperative Extension. Publication 348-594. 2013.  Page 12. Accessed March 2015 at https://pubs.ext.vt.edu/348/348-594/348-594_pdf.pdf Water bath processing minimizes the risk.  ^[33]Ibid. Page 12.

2. The colour of your jam

Second, sugar acts as a preservative. If you reduce the amount of sugar in your jam or jelly, its shelf life will not be as long. This is not necessarily a bad thing, but it’s important to know, particularly if you’re making jam to give or sell others.”  ^[34]McClellan, Marisa. Canning 101: How to Can Creatively and Still Be Safe. From: Food in Jars blog. 15 December 2010. Accessed March 2015 at https://foodinjars.com/2010/12/canning-101-how-to-can-creatively-and-still-be-safe/

The colour of your reduced or sugar-free jam will change faster than the colour of sugar laden jams. It happens even with commercial ones. This won’t affect the quality, the safety or the taste, and besides, the USDA wants us to use up home canned goods within a year anyway.

In some cases, the preserves may darken. In others, they may fade. But when stored in good conditions, this colour change shouldn’t even start to be noticeable until approaching the second year mark.

3. Shorter life once opened

We’re all used to opening a jar of store-bought, high sugar jam, using a bit, putting the lid back on and putting it back in the fridge and then using it sporadically over the next few years — and it’s fine.

That’s not going to happen with reduced or sugar-free jams, whether store bought or home made. Sugar’s real role as an aggressive quality preserver really comes into its own once your sealed jar is opened. Even refrigerated, moulds will slowly attack it, and without sugar to kill the spores by depriving them of water, will eventually win.

Consequently, unless you are routinely feeding crowds, reduced or sugar-free jams may be better made in smaller sizes such as ¼ litre (250 ml / ½ US pint / 1 cup) rather than larger, “farm hands breakfast table” sizes such as ½ litre (1 US pint). Or smaller even, such as the 125 ml (¼ US pint / ½ cup) sampler sizes. Aim perhaps for a size you can use up within 4 to 6 weeks, refrigerated, once opened.

Jams made with pectin with preservatives in it will probably experience a longer “after-opening” life than preservative-free ones such as Pomona.

Miscellaneous information

Elizabeth Andress of the NCHFP says, “We are starting to use that [Ed: a little bit of butter or margarine in jelled fruit products] in some of our lower sugar jams and jellies that tend to get a lot of trapped air to reduce some of the air there also… It shouldn’t be enough to interfere with the gel at all.”  ^[35]Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. At 1:30. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv

Don’t use a food processor on fruit for jam: the blade of a food processor damages the natural pectin in fruit.

“Jams and jellies made with artificial sweeteners and unflavored gelatin or added pectin generally provide 8 to 12 calories (2 to 3 grams carbohydrate) per tablespoon. Those made with a commercial low-calorie jelling mixture such as maltodextrin provide 16 to 20 calories (4 to 5 grams carbohydrates) per tablespoon.”   ^[36]Kendall, P. Canning Fruits. Colarado State University Extension. No. 9.347. June 2013. Accessed March 2015 at https://www.ext.colostate.edu/pubs/foodnut/09347.html 

Further Reading

Ball sugar-free jam (video)

Clearjel for Jam: Austin, Joanne. Using Clearjel. WSU Skagit Country Extension. October 2007.

Driessen, Suzanne. Low Sugar Alternatives for Jams and Jellies. University of Minnesota Extension Service. 2014.

Gupta, Sujata. What Makes A Jam A Jam? Surge In Savory Spreads Presents Riddles For Purists. NPR Digital Media. 22 August 2016.

Hart, Anne. You don’t have to add sugar to homemade marmalade, jam, jelly, or fruit butter. Examiner. 11 January 2012.

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