Published September 1, 2005.
In general, we find that preserves and jams have more fruit flavor than jellies. We tested six brands to find our favorite raspberry flavor.
For this tasting, we first needed to define the difference between jellies, jams, preserves, and fruit spreads. A jelly is a clear, bright mixture made from fruit juice, sugar, and often pectin or acid. A jam is a thick mixture of fruit and sugar that is cooked until the pieces of fruit are very soft and almost formless. Preserves are almost identical to jams, but preserves may contain large chunks of fruit or whole fruit.
In most markets, jellies have been almost completely replaced by fruit spreads (made with juice concentrates, usually pear and white grape). Fruit spreads do not fall under the labeling standards applied to jellies and jams—hence the generic name, "fruit spreads." These products are usually made with concentrated grape and/or pear juice or low-calorie sweeteners, which replace all or part of the sugar.
In our raspberry tasting, tasters felt that the concentrated fruit juices in fruit spreads obscured the flavor of the raspberries. The result was a generic “fruit roll-up flavor," lacking a strong, recognizable raspberry flavor and being one-dimensionally sweet.
Based on our tasting, only a jam or preserve will do; tasters liked the bits of fruit. The difference between the two is minor; the term "preserve" implies the presence of large pieces of fruit, while a jam should have a smooth and uniform consistency. Most importantly, their flavor should speak loudly of raspberry, without too much tartness or cloying sweetness. As a final note, seedless versions came across as artificial and overprocessed.