LESS FAT. FULL FLAVOR. ICE CREAM GETS A MAKEOVER WITH THE HELP OF SPX EQUIPMENT.

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1 ICE CREAM GETS A MAKEOVER WITH THE HELP OF SPX EQUIPMENT.

2 SPX IS PLAYING A ROLE IN SUPPORTING AND SPURRING ADVANCES IN ICE CREAM PRODUCTION. Cooler Ice Cream Production From Tel Aviv to Tokyo, it seems most everyone loves ice cream. The frozen concoction has become one of the world s most popular treats whether it takes the form of Israeli glida, Italian gelato, Indian kulfi or a U.S.-originated ice cream brand. As the popularity of ice cream has grown, so has the interest in making it more appealing to prospective customers through the introduction of exotic flavors, convenient packaging options, intriguing shapes, longer shelf life and enhanced nutritional content. SPX is playing a role in supporting and spurring advances in ice cream production, including recent developments that are making ice cream an even more popular dessert choice worldwide. SPX s Ice Cream Connection From heat exchangers and valves to spray dryers and emulsifying equipment, SPX products and technologies have been used by numerous ice cream producers in various stages of ice cream production to both enhance product quality and help optimize production. For example, the APV brand Flex Mix Instant, an inline batch mixer, uses vacuum pressure to draw powdered ingredients into a circulation liquid below the liquid surface. However, it has been in the area of low temperature extrusion (LTE), a technology that makes it possible to yield ice cream with a lower fat content and yet the creaminess of traditional ice cream. The Freezing Process To understand how LTE works, it is important to understand how ice cream is made. The basic steps are blending the ingredients, pasteurizing and then homogenizing the mixture, aging the mixture, freezing it, packaging it and then hardening it. Freezing is among the most important steps in ice cream production. This is where the ice cream mixture is transformed from a liquid oil-in-water emulsion to a frozen state. As the water in the mixture freezes, the concentration of dissolved solids increases. Many of the emulsion drops are destroyed and fat agglomerates or forms clusters. Air is then incorporated and dispersed in the ice cream. The addition of air, called overrun, contributes to the texture (lightness or denseness) of ice cream. Without it, ice cream would be similar to a frozen ice cube. Up to 50% of the volume of finished ice cream (100% overrun) can be air that is incorporated during freezing. The overrun level can be set as desired to adjust the denseness of the finished product. Premium ice creams have less overrun (approximately 80%) and are denser than regular ice cream. Large ice crystals form at this stage. If the water and ice crystals are not bound efficiently by the agglomerated fat, these crystals can give ice cream a grainy texture and affect its quality during temperature fluctuations. To counterbalance this, manufacturers typically add milk fat. The quality of the ice cream can then be further improved by cooling (hardening at cold temperatures) after the freezing step. 2

3 If the water and ice crystals are not bound efficiently by the agglomerated fat, these crystals can give ice cream a grainy texture and affect its quality during temperature fluctuations. To counterbalance this, manufacturers typically add milk fat. The quality of the ice cream can then be further improved by cooling (hardening at cold temperatures) after the freezing step. As the ice cream is drawn with about half of its water frozen, flavorings such as fruits, nuts, candy or cookies can be added to the semi-frozen slurry, which has a consistency similar to soft-serve ice cream. After the particulates have been added, the ice cream is packaged and is placed into a blast freezer at -30 to -40 C where most of the remainder of the water is frozen. Below about -25 C, ice cream is stable for indefinite periods without danger of ice crystal growth; however, above this temperature, ice crystal growth is possible and the rate of crystal growth is dependent upon the temperature of storage. This limits the shelf life of the ice cream. As the popularity of ice cream has grown, so has the interest in making it more appealing to prospective customers through the introduction of exotic flavors, convenient packaging options, intriguing shapes, longer shelf life and enhanced nutritional content. For more information visit Low Temperature Extrusion In the last decade, a new technology has emerged for ice cream production called low temperature extrusion (LTE). The application of this technology allows ice cream to be made with much smaller ice crystals and smaller-sized fat globules and air cells in its structure. The advantages of the methodology is that ice cream can be manufactured that is low in fat (one-third fewer calories and half the fat) while maintaining the creaminess, texture and taste of full fat conventional ice cream. In addition, no additional hard freezing is required after the extrusion process. The ice cream is simply packaged and stored prior to shipping. SPX Aids Slow Churn Ice Cream SPX equipment has played an important role in supporting the use of LTE. For example, SPX provided over 900 single seat and PMO (pasteurized milk ordinance) Waukesha Cherry-Burrell (WCB) mix proof valves for use in a U.S.-based company s slow churned ice cream production process. The slow churned ice cream, marketed as a light ice cream, uses a proprietary technology to produce reduced-fat ice cream with all the taste and texture of the full fat product. The SPX equipment helps control flow of product and CIP cycles from over a dozen pasteurized mix tanks. 3

4 Kombinator X250 Another SPX brand, Gerstenberg Schroeder, has become a well-known fixture in ice cream production facilities using LTE. The Gerstenberg Schroeder Kombinator X250 scraped surface heat exchanger was developed specifically for using LTE to produce lower fat ice cream with the same creamy texture and taste as full-fat ice cream. The Kombinator X250 ensures fast cooling of pre-crystallized ice cream. The process improves the ice cream texture, which results in a creamier, less icy product with a longer shelf life. In addition, savings of high cost ingredients can be achieved as high quality ice cream can be produced with lower content of fat and protein. How It Works The mechanical treatment at very low temperatures in the Kombinator X250 has a large impact on the microstructure and characteristics of the ice cream, resulting in improved quality. The addition of shear and prolonged treatment during this low temperature extrusion process minimizes further the air cell size and the size of air crystals. Additionally, an increased amount of fat globule aggregates is generated which results in improved melting resistance, improved shape retention and reduced serum drainage. The change in the disperse microstructure of LTE-processed ice cream has a positive impact on ice cream quality characteristics such as scoopability and creaminess when compared to conventionally frozen and hardened ice cream. Scoopability is improved due to smaller ice crystals, which determines the rigidity and scoopability of ice cream at low temperatures. A higher level of creaminess in the melted state at temperatures above 0 C corresponds to the small air cell size of LTE ice cream. High shear forces are also able to form an optimized network of agglomerated fat globules, which further stabilizes the ice cream mixture. This change in the microstructure makes it possible to produce ice cream with a lower fat content that has a creamy texture like products with higher fat content. The quality of the ice cream can be further evaluated by employing melt-down tests to show how the fat has crystallized and agglomerated. If the ice cream consists of a higher ratio of fat globules below 20 microns, the melted ice cream will maintain its shape for a longer period of time. Energy Savings Use of the Kombinator X250 also can help reduce energy consumption, and thereby production costs. Production time of the ice cream is short and more efficient since the LTE technology partly or complete eliminates the hardening stage and the equipment associated with it. The design of the Kombinator X250s rotor also minimizes the mechanical energy transferred to the ice cream, resulting in a more efficient cooling process. The special corrugated cooling tubes further improve heat transmission. The change in the disperse microstructure of LTE-processed ice cream has a positive impact on ice cream quality characteristics such as scoopability and creaminess when compared to conventionally frozen and hardened ice cream. 4

5 High shear forces are also able to form an optimized network of agglomerated fat globules, which further stabilizes the ice cream mixture. This change in the microstructure makes it possible to produce ice cream with a lower fat content that has a creamy texture like products with higher fat content. From heat exchangers and valves to spray dryers and emulsifying equipment, SPX products and technologies have been used by numerous ice cream producers in various stages of ice cream production to both enhance product quality and help optimize production. Lower Maintenance Costs All seals on the Kombinator X250 are easily replaceable, helping to minimize production downtime due to equipment maintenance. The central product outlet that ensures an even temperature profile of the finished ice cream product also facilitates easy inspection of the product seal. All main refrigerant valves are placed on top of the unit for easy access. The equipment s design makes installation and rearrangement in the production facility fast and easy. With the option of a mirrored version, it is possible to place two Kombinator X250 units side by side or staked on top of each other to save floor space. The hygienic design also makes cleaning-in-place fast and simple. Global Headquarters Ballantyne Corporate Place Charlotte, North Carolina United States 2011 SPX CORPORATION 5