A P P L I CAT I O N S H E E T
Ice Cream With Improved Mouth-Feel
Ice cream is a complex multi-phase system consisting of ice
crystals, air cells, protein and fat globules embedded in a frozen
high viscous and concentrated matrix. The microstructure of
these constituents has significant impact on the consumer quality
characteristics.
The process for conventionally frozen and hardened ice cream is:
• Mixing
• Pasteurization
• Homogenization
• Cooling to below 5°C and then ageing
• Freezing to -5°C and incorporation of air
• Filling or packing
The mechanical treatment at very low temperatures in the GS
• Hardening to -18°C
Kombinator X250 has a large impact on the microstructure and
• Storage and distribution at -30°C
characteristics of the ice cream resulting in improved quality.
One of the most important steps in ice cream production is the
freezing step where the ice cream mix changes from a liquid
oil-in-water emulsion to a frozen state. Many of the emulsion
drops are destroyed and the fat agglomerates. Air is incorporated
and dispersed in the ice cream (up to 50% of the ice cream
is air). If the water and ice crystals are not bound efficiently by
agglomerated fat, large ice crystals will be formed and the quality
of the ice cream will decrease during temperature fluctuations.
The quality of ice cream can be significantly improved by
implementing further cooling after the freezing step. Low
temperature extrusion (LTE) is used for this process, where the
ice cream is cooled down further from -5°C to -15°C by using the
Gerstenberg Schröder ice extruder technology, GS Kombinator
X250.
The addition of shear and prolonged treatment during this low
temperature extrusion process minimizes further the air cell size
by a factor 2-3 and the size of ice crystals is reduced by factor
1.5. Additionally, an increased amount of fat globule aggregates
is generated in the size ranging from 2 to 20 μm, which results
in improved melting resistance, improved shape retention and
reduced serum drainage.
The change in the disperse microstructure of low temperature
extrusion processed ice cream has a positive impact on the ice
cream quality characteristics such as scoopability and creaminess
when compared to these in conventionally frozen and hardened
ice cream.
Scoopability is improved due to smaller ice crystals, which
Customer tests have confirmed that ice cream produced by low
determines the rigidity and scoopability of ice cream at low
temperature extrusion using GS Kombinator X250 show improved
temperatures. A higher level of ‘mouth-feel creaminess’ in the
quality characteristics. The low temperature extrusion technology
melted state at temperatures above 0°C corresponds to a smaller
results in the following benefits:
air cell size of the LTE ice cream.
• Creamier, less icy product
High shear forces are also able to form an optimized network
• Optimized reduced fat products due to improved creaminess
of agglomerated fat globules, which further stabilizes the ice
• Shorter and smaller hardening facilities
cream foam. This change in the microstructure makes it possible
• Energy saving
to produce ice cream with lower fat content exhibiting similar
• Longer shelf life due to smaller ice crystals
creaminess as products with higher fat content. The quality of the
ice cream can be evaluated by melt down tests which will show
how the fat has crystallized and agglomerated. If the ice cream
consists of a higher ratio of fat globules below 20 micron the
melted ice cream will maintain it shape for a longer time.
GS Kombinator X250
Denmark: P: +45 7027 8222 F: +45 7027 8223 E: [email protected]
Germany: P: +49 451 3709 0 F: +49 451 3709 311 E: [email protected]
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SPX Corporation reserves the right to incorporate our latest design and material changes without notice or obligation. Design features, materials of construction and dimensional data, as described in this bulletin, are provided for your information only and should not be relied upon unless confirmed in writing.
ISSUED 07/2012 A4_GB
COPYRIGHT © 2012 SPX Corporation