Food 12 | 2014
Enveloping to size
Extrusion for encapsulation of active ingredients and additives
Encapsulated active ingredients and additives are becoming increasingly important in many areas of application. Encapsulation is to be understood as all procedures for the complete envelopment or embedding of liquid drops, solid particles or also gases in a solid enveloping substance (matrix). Core material and matrix are not mixable with each other. The main reason for the encapsulation is the protection of the core material against damaging influences such as light, oxygen and moisture. In addition, nutritional and health issues may be in focus to release ingredients at specific places in the digestive tract or with delayed action. But the largest area of application is most probably the encapsulation of flavors to guarantee optimum taste experience at the time of eating.
Spray drying and extrusion are the encapsulation methods most frequently used in food processing - whereby extrusion with the co-rotating twin screw extruder ZSK has a number of advantages over spray drying. In the ZSK extruder, the encapsulation takes place in a highly viscous medium; there is no complex, product-damaging and uneconomical redrying step. In addition, the temperature control in the extrusion process can be selected independently of evaporation temperatures of solvatation agents (usually water). The substance to be encapsulated is normally not added until after formation/structuring of the envelope matrix. There is also a wide choice of possible matrix materials. Extruded capsules are completely surrounded by the enveloping substance with the exception of the enclosures touching the pellet surface. Unlike spray-dried products, they can be moistened well without further agglomeration steps.
In the extrusion process, powder is fed into the process section of the ZSK first, usually a hydro-colloid or a suitable premix with film-forming properties. Water or softeners are added downstream as required and later the product to be encapsulated. A homogeneous, highly viscous, low water mixture of core material and envelope matrix is created with different process steps such as mixing, kneading, cutting and heating in the process section of the ZSK which usually only requires little drying or cooling afterwards. The melt is cut into solidifying pellets by means of the concentric pelletizer ZGF directly after being discharged from the nozzle. In this way, spherical or elliptical products from a diameter of 0.5 mm that are mechanically stable can be produced. They have a load of below 10% to max. 25%. Post-treatment of the surface is possible to remove free drops/particles. Depending on the machine size, throughput rates of 1 to 10 kg/h in the laboratory and up to several 100 kg/h on a production scale can be achieved by extrusion.
Coperion has long years of experience and extensive knowledge in the development of extrusion systems for the encapsulation of solids and liquids such as flavors, vitamins, feed additives or pharmaceutical ingredients. The intensive mixing behavior of the ZSK twin screw extruder ensures a highly dispersive distribution of the ingredients. At the same time the kneading and mixing take place in the process section of the ZSK with low shearing and low temperature so that highest product qualities are achieved. The continuously operating extrusion system is completely enclosed and therefore offers hygienic advantages. The process section has a modular structure consisting of individual barrels and screw elements and is used in different sizes for a wide range of applications - among other things for micro-incapsulation.
Stefan Gebhardt, Phone: +49 (0)711 897 3048, e-Mail
For the high hygiene requirements of the food and pet food industry
Batch weigh system with P100 batch weigh receiver and KT20 gravimetric feeder
In many cases, the transfer and weighing of majors, minors, and micros to the blending step can be a manual and labor intensive process. In an effort to improve process efficiency and product quality, the complete batching process can be automated. This includes the automated transfer of the raw ingredients to the batching system, where the ingredients are prepared in the required proportions before being delivered to the mixing process.
Coperion K-Tron’s vacuum receivers and loaders are ideal for the pneumatic transfer of a wide range of bulk materials in the food and pet food industries, from free-flowing granulates to difficult powders. The P100 batch weigh receiver combines a vacuum receiver with a reliable weighing system, which accurately measures the amount of material being drawn into the weigh hopper. This technology allows multiple ingredients to be conveyed and weighed so that accurate batching of ingredients can take place – up to 8 components can be sequentially added to the batch weigher. With this type of scale weighing system, typically weigh accuracies of +/-0.5% of the full scale capacity can be achieved. Once the desired batch has been achieved, the mixer then calls for material, a butterfly valve opens and the material in the scale hopper is discharged. Batch weigh receivers are ideal for delivering higher volumes of major ingredients – such as flour, sugar, starch, etc. – to the process, when precise accuracy of the ingredient is not as critical.
Often smaller amounts of additives must be added to a large batch of main ingredients. Loss-in-weight feeders – such as the KT20 twin screw feeder – are ideal for the accurate dosing of additives such as vitamins or probiotics to the process in small amounts. Coperion K-Tron’s patented SFT digital weighing technology delivers the high accuracy requirements needed for maintaining control of the addition of costly ingredients. Coperion K-Tron offers a wide variety of screw and agitator designs, in order to give best results for a variety of ingredients. The feeders are all designed with ease of cleaning and maintenance in mind and all product contact parts are constructed to conform with strict cGMP standards. All product contact parts are made of stainless steel, with continuous welds and polished walls. Triclover clamps and metal caps allow for quick and easy cleaning or disassembly.
Properly weighing and accurately delivering the ingredients without manual intervention can result in a number of process advantages, including fewer mistakes, better accuracy, lower bulk costs, improved product quality and savings in manufacturing costs. The use of highly accurate weighing and feeding components and systems for handling costly ingredients, such as probiotics or vitamins, can reduce waste and raw material costs.
Sharon Nowak, Tel.: +1 856 256 3119, e-Mail
Coperion K-Tron’s Smart Weigh Belt
Metering ingredients for snack mixes
Multi component snack mixes are becoming popular quick snack options. Coperion K-Tron has supplied a variety of weigh belt feeders / system combinations for the metering of these components into the mix and prior to the packaging line. By utilizing a high accuracy feed mechanism, such as the Coperion K-Tron Smart Weigh Belt (SWB), the enduser can be assured of ingredient cost control and high product quality.
The SWB is used for continuous controlled gravimetric feeding of bulk materials. This feeder features a primary weighbridge and offers an optional secondary weighbridge that provides continuous online auto tare, reducing maintenance, frequency of calibration, and improving long term stability. The SWB is offered with a stainless steel enclosure and an easy clean design, with a removable conveyor assembly, allowing easy access for maintenance an belt removal.
In most blend applications, ingredients are delivered to the ingredient bins via bags, boxes, drums or supersacks. Once these ingredients are transferred to the product bin, a slide gate at the bin discharge is opened to allow flow of the product to the SWB feeder hopper below. Each individual component is metered by the SWB based upon a predetermined recipe, and discharged to a horizontal conveyor. The product in this conveyor is then sent to a carousel type packaging machine. The basic features of the SWB controls package allow the sequential starting and stopping of each ingredient line. During this process, the first weigh belt feeder discharges the initial ingredient to the horizontal conveyor. The remaining belt feeders then discharge their ingredients sequentially, in accordance with the programmed sequence of operation, thus creating a natural layered mix. The number of the belt feeders in the line can vary, dependent upon the number of components in the mix. One recent Coperion K-Tron customer utilized 14 feeders in three lines, in order to create up to 30 different blends of products, with a maximum of seven individual components in each mix.
Smart Weigh Belt Feeder (SWB)
- Typical flow rates: 20 - 40,000 kg/hr (44 - 88,000 lb/hr)
- Availability of second weigh bridge with continuous taring ensures that either dust buildup or product buildup on weighing device has no effect on an overall accuracy
- Less space requirement at equivalent accuracies of screw feeders
- Coperion K-Tron SmartConnex control capabilities to allow for a variety of programming options including ingredient control and recipe management
- Improved belt cleaning design as well as reduced maintenance requirements
- Trapezoidal inlet design allows for improved material flow from feed storage bin
- Models available in open frame or closed frame designs for ease in accessibility , cleaning and maintenance
- Minimal product damage or attrition due to gentle action of weigh belt
Sharon Nowak, Tel.: +1 856 256 3119, e-Mail
We look forward to seeing you there
Trade shows and presentations in spring 2015
Right at the beginning of 2015 Coperion will be represented at many trade shows and conferences. Visit us at our booths or at one of the conferences. We look forward to your visit!
Rennes / France
Mar 10 - 12, 2015
Hall 5, Booth no. E 41
Follow this link to find an overview of all trade shows Coperion will be attending:
Pasta Technology 2015
Corpus Christie, TX, USA | Feb 11-13, 2015
Food Automation and Manufacturing Conference & Expo 2015*
Clearwater Beach, FL, USA | Apr 12-15, 2015
*) Coperion and Coperion K-Tron can offer you the participation at a reduced price of 500 USD. Interested? Please contact:
Shari Lake, Tel.: +1 785 825 3884, e-Mail
Follow this link to find an overview of all conferences Coperion and Coperion K-Tron will be attending: