Written by Bauman College Staff
High concentrations of sugar, as with salt, can preserve foods for long periods of time, and are traditionally used to thicken and preserve fruit spreads. This is an economical method of preservation but not the most nutritious, as evidenced in the conventional jams and jellies we find on supermarket shelves that are loaded with large quantities of refined white sugar. There are, however, other methods for preparing fruit jams and jellies that use alternative sweeteners and natural thickeners. The result is a healthier, homemade, additive-free, delicious treat that tastes more like the fruit it was made from than the sugar used to preserve it.
Ever wonder what the difference between jelly and jam is? While all types of fruit preserves consist of a careful balance of fruit, sugar, acid, and thickener, each type is slightly different:
- Jelly is a semi-solid mixture consisting simply of fruit juice and sugar. It is clear, firm, and holds its shape.
- Jam is a mixture of chopped or crushed fruit combined with sugar. It is less firm than jelly but still holds its shape.
- Preserves consist of small, whole or large pieces of fruit suspended in a clear, thick syrup.
- Marmalade consists of small pieces of citrus fruit or peel suspended in a clear, soft jelly.
The Role of Sugar
Sugar serves several necessary functions in a fruit spread, the least of which is to sweeten the mixture. More importantly, sugar interacts with the natural pectin in fruit to encourage gelling, as well as preventing spoilage. By reducing available moisture (with appropriate temperature and processing time), the presence of sugar actually inhibits microbial growth.
Fortunately, reducing or eliminating sugar in jams, jellies and preserves is possible, provided one takes these factors into account. Alternative sweeteners, such as honey, can be used in combination with a gelling agent (see Alternative Thickeners below) such as gelatin or agar agar to produce a similar effect. Commercial pectin – extracted from fruit – also comes in low or no sugar varieties that can drastically reduce the amount of sugar needed to successfully preserve and gel your spread. Some fruits even contain enough naturally occurring pectin to be used with very little sugar added; marmalades, for example, rely entirely on the natural pectin in citrus peel to gel.
Pectin is a naturally occurring polysaccharide found in all fruit that binds with water in an acidic environment (usually a bit of lemon juice), forming a gel. Traditionally, homemade jam was made by cooking down fruit for hours until the pectin in it caused the mixture to thicken. Because of the long cooking time, however, this technique boils out the vitamins and calls for a lot of sugar to activate the gel – therefore greatly reducing the nutritional value of your fruit spread. Today, pectin is naturally and safely extracted from fruit and sold in powder or liquid form, allowing for less cook time and less sugar, with the same gelling results.
Natural pectin levels are higher in some fruits than others, and highest in fruit that is not quite ripe. Depending on the type and the ripeness of the fruit you’re using in your spread, you may or may not need to add pectin, sugar, and acid, as shown in the chart below:
Pectin & Acid Levels in Fruit
|High Levels||Medium Levels||Low Levels|
|Apples (sour)Blackberries (sour)Crabapples
Grapes (Eastern Concord)
Plums (not Italian)
Citrus skins (lemons, oranges, grapefruit, etc. – the peels but NOT the fruit)
|Apples (ripe)Blackberries (ripe)Cherries (sour)
Grape juice, bottled (Eastern Concord)
Grapes (Western Concord)
High Levels – has enough natural pectin & acid for gel formation with only a small amount of sugar added
Medium Levels – may need addition of either acid or pectin
Low Levels – always needs added acid, pectin, or both.
Source: National Center for Home Food Preservation
Pectin comes in liquid form, in regular dry powder form, and in low- and no-sugar dry powder form. The folks at Pick Your Own (www.pickyourown.org) , whose website has great tips for all types of seasonal canning and preserving, recommend using dry, no-sugar pectin for any type of jelly or jam, and simply substituting a splash of fruit juice instead of sugar. Remember, the National Center for Home Food Preservation recommends processing low- or no-sugar jams for longer periods in a boiling water canner to prevent spoilage.
While pectin is the most commonly used gelling agent for jams and jellies, there are others out there that can not only produce similar effects, but are richer in nutrients and more health-supportive. Just keep in mind when using an alternative thickener that the consistency and finish of your end product may vary.
Derived from animal bones (primarily cattle bones or pig skin), gelatin is a classic thickener that produces a shiny, glossy finish to your product. Although commercial gelatin — such as Jell-O — comes from unhealthy sources, gelatin obtained from clean, organic, humanely treated animals is very nutritive: it supports hair and nail growth, joint health, and treats arthritis.
Gelatin comes in sheets, granule, or powder form, and can be made into a slurry to add to hot mixtures. Avoid using in combination with fruits that contain bromelain (found in pineapple, kiwis, fig, guava, ginger, papaya) as it will break down gelatin and diminish its gelling qualities.
Known as kanten in Japan, this gelatin-like thickener is derived from seaweed, and is commonly used in Japanese desserts. Not only is agar-agar a great stabilizing and thickening agent, it’s also highly nutritive. Made from red algae, it is rich in carotenoids as well as iodine and other minerals. Agar-agar comes in flake or powder form, has a whitish-clear appearance, and should be dissolved in liquid over heat before use. It sets up firmly at room temperature with a glossy finish, similar to Jell-O. You may want to stir a jam made with agar-agar before serving to ensure a smooth consistency.
This starch derived from the root of a rainforest plant is commonly used in gluten-free baking and as a cornstarch alternative to thicken sauces and soups, as it is much more digestible than corn. Arrowroot comes in the form of a white, silky powder, and should be mixed with liquid in a slurry or paste before whisked lightly into your fruit mixture. Cook it slightly to get a smoother flavor. The mixture will set as it cools, producing a jam that is not as firm as one made with gelatin or agar-agar, but still has a glossy finish.
These powerful little seeds were used by Aztec warriors as an energy-boosting superfood, and are packed with Omega 3 fatty acids, fiber, and protein — a highly nutritious choice for your spread! Typically used as a binder in gluten-free baking, smoothies, and sprouted in salads, these seeds swell when mixed with liquids and can be used whole or ground. Whole chia seeds will add some texture to your spread — which may or may not be the desired effect, but can be very pleasing. Ground chia seeds will produce a smoother consistency, but with a dusty appearance (rather than glossy). Simply add to the liquid and allow to rest; the jam will set up as it sits, no heating required.
Morris, William (2012). Food preservation: Low or no sugar in jams, jellies, and preserves. Agricultural Extension Service, University of Tennessee. Retrieved from: http://wcmorris.com/canning/files/SP325-F.pdf
Pick Your Own.org (2012). Notes about pectin for making homemade jam. Retrieved from: http://pickyourown.org/pectin.htm
The National Center for Home Food Preservation (2012). Making jams and jellies: General information on jams, jellies, and marmalades. Retrieved from: http://nchfp.uga.edu/how/can_07/prep_jam_jelly.html