Some freeze-dried berry powders—especially freeze-dried strawberry powder—can act as outstanding stabilizers in ice cream and other frozen dairy desserts.
Researchers at the Agricultural Research Service (ARS) discovered that freeze-dried fruit powders including strawberries, blackberries and raspberries improved the taste and structure of ice-cream and other frozen desserts.
Freeze-dried strawberry powder was particularly effective. Frozen dairy desserts with it included will maintain their shape even after reaching room temperature, according to the research.
"We discovered that some of the freeze-dried fruit powders—especially strawberries—completely prevent the melt-down of dairy frozen desserts similar to ice cream made with whole milk, whole whipping cream, sugar and skim milk powder," said Cristina Bilbao‐Sainz, who led the study. "Freeze-dried berry powder will absorb moisture from the premix base, improving its stability and texture to the point where the frozen dessert will keep its shape even after "melting" to room temperature."
This is probably due to the fiber in the berry powder becoming completely hydrated, which contributes to an increase in viscosity and resistance to melt-down, she explained.
The research added 3.5 per cent of freeze-dried strawberry, raspberry, blackberry and blueberry powder to ice cream. This equated to roughly 20 grams of powder per litre of ice cream. Strawberry powder was found to act as the most effective stabiliser, completely preventing melt-down, followed by raspberry and blackberry. Blueberry powder was found to have a minimal effect.
The research offers food processors exciting new opportunities to offer consumers clean label solutions in their ice creams and deserts.
Without a stabilizer, ice cream—home-made or commercial—can become unpleasantly crunchy with the growth of large ice crystals. It can happen in either or both the ice cream maker or the freezer, when temperatures change. Stabilizers also slow down melting, prevent wheying off (the leaking of a clear watery serum), help avoid shrinking during storage and increase your mouth's perception of creaminess.
Standard stabilizers such as sodium alginate, guar gum, iota carrageenan, xanthan gum and carboxymethyl cellulose are commonplace. But people tend to react negatively to these unfamiliar, chemical sounding names when they appear on an ice cream label, assuming these must be artificial ingredients.
With a rise in consumer demand for natural ingredients driving new food markets, food processors can benefit from using raw ingredients in sweet products, according to Diana Morris, Country Manager UK from European Freeze Dry.
She said: “This research allows ice-cream producers and makers to revisit the stabilisers that they use in their products and move to a raw fruit alternative that is more attractive to consumers.
“While different varieties of fruit powders were tested as part of the research, strawberry powder was found to be the most effective as a stabiliser, with raspberry powder also having a positive effect.”
She added that the reduction in water in the final freeze dried product means there is a much reduced potential for microorganisms existing in such low amounts of water, leading to a shelf life of up to two years at room temperature.
Functionality of freeze‐dried berry powder on frozen dairy desserts
Journal of Food Processing and Preservation
Authors: Cristina Bilbao‐Sainz, Sandy Thai, Amanda J. G. Sinrod, Bor‐Sen Chiou, Tara McHugh