logging in or signing up Extrusion Overview ramabhau Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 1614 Category: Science & Tech.. License: All Rights Reserved Like it (0) Dislike it (0) Added: January 09, 2012 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript PowerPoint Presentation: Dr. R. T. Patil , PS & Ex-Director, CIPHET, Ldh . Central Institute of Agricultural Engineering, Bhopal 462 038 (MP) Developments in Extrusion Technology-An overviewPowerPoint Presentation: A single machine conveys, mixes, kneads, cooks and forms in one continuous process. The energy input comes mainly from the conversion of mechanical to thermal energy. Extruded food materials undergo various transformations like starch gelatinization, fragmentation and protein denaturation It is widely used to manufacture breakfast cereals and snacks and other emerging application to increase process efficiencies. Extrusion ProcessingPowerPoint Presentation: Low-shear (forming) extruders: used to increase density of material that is generally high in moisture (e.g. pasta) using low screw speeds. Medium-shear stress: used to process raw materials with lower moisture content with higher energy inputs (e.g. pet foods, aquatic feeds, texturized vegetable protein). High-shear stress: where extrusion speeds and energy inputs are high to process low-moisture raw materials in a short length-to-diameter ratio barrel. Highly expanded products are obtained (e.g. snacks, breakfast cereals). Classification of Extrusion ProcessesPowerPoint Presentation: Single-screw extruders Consists of a rotating extruder shaft with screw elements (may be segmented screws and shearlocks), a stationary barrel housing (maybe segment sections), and a die and knife assembly. Twin screw extruders Counter-rotating twin-screw extruders (screws move in opposing directions, low speeds and long residence times) for production of gum, jelly and licorice confections. Co-rotating twin-screw extruders(screws move in same direction, high degree of heat transfer but not forced conveyance) for snack products. An intermeshing screw producing a positive pumping action, efficient mixing and self-cleaning. Non-intermeshing screws depend on friction for extrusion, like single-screw extruders Classification of ExtrudersPowerPoint Presentation: Second generation snacks: are those that expand when they come out of the extruder. This is the most popular type of expanded snack. Third generation snacks: or pellets do not expand when they come out of the extruder. After storage, the pellets are puffed by frying, microwave heating or hot air puffing. Expanded Snacks Produced by ExtrusionPowerPoint Presentation: Have angled steam injector ports oriented in the direction of material flow, along with a unique screw profile that allows steam to be mixed into the product and can utilize up to four times more thermal energy than the average twin screw machine. They translate thermal to mechanical energy ratios of 14:1, lowering energy costs, less wear and a lower environmental impact. Potential to produce specialty foods including up to 90 percent fresh meat (as a percent of the dry recipe) and up to 40 percent moisture without changing the extruder configuration. Thermal Twin Extrusion SystemsPowerPoint Presentation: Supercritical CO 2 is injected into mixer and extruder to provide proofing of the product. Rising of the dough is achieved by a combination of hydrodynamic expansion of air bubbles and diffusion of CO 2 into these bubbles without the need for yeast. The controlled acid hydrolysis of the starches in the dough helps to produce reducing sugars that add desirable flavor to the final product. Super Critical Fluid Extrusion for Breadlike ProductsPowerPoint Presentation: Solvent Extraction Oil extractability is increased by enhanced micro-porosity for easier hexane penetration, enhanced macro-porosity for decreased solvent hold up after extraction increasing soybean oil mill up to 50 % Mechanical Expelling Dry extrusion improves the throughput of the expeller. Oil recovery of 70 % was reached in a single pass with the cake having 6 % of residual oil and a 90 % deactivation of TI activity with oil having less free fatty acids, lower peroxide value and lower phosphorus content while enhanced tocopherols content. Process requires low capital investment and enables processing in small production catchment There are more than 100 plants in North America (capacity 5-20 metric ton / day) comapred to only one commercial plant in India. Extrusion to Improve Oil Expression and ExtractionPowerPoint Presentation: Capacity 100 kg /h • Oil recovery 65 – 70 % in single pass • Good quality MFSF (Protein 48 %, Fat 6-8 %, TI Inactivation up to 70 %) •Development of commercial unit ( 250 kg /h) in progress in collaboration with a manufacturer Integral Extrusion Expelling UnitPowerPoint Presentation: Application of Expander in Oil Extraction This is used for Soya beans, cotton seed, wet corn germ, sunflower seed, rapeseed, salseed and many of the seeds and (fully or pre-pressed) oil cakes to make the meat porous and homogenous.PowerPoint Presentation: At CIPHET Ludhiana, we developed Ready-To-Eat snack foods from minor millet viz., foxtail millet, proso millet, little millet, barnyard millet and kodo millet using low cost collet extruder. The retexturized fruit bars were prepared incorporating dehulled bengal gram blended maize extrudates with banana (Musa paradisaca L.), mango (Magnifera indica L.) and papaya (Carica papaya L.) fruit pulps. Using twin screw extruder Extrusion of millets/fruit pulp for health foodsValue Added Products from Rice Brokens: Value Added Products from Rice Brokens High percentage of brokens is a problem in summer rice due to climate change (18-40%) Brokens fetch very low price Extrusion is a novel technology to produce expanded blended products under high temperature short time regime CIPHET has modified the low cost collet extruder to produce expanded ready to eat snacks using rice and pulse brokens. The cost of the unit is Rs 2 Lakh, capacity 25 kg/h, cost of accessories Rs. 2 lakh and thus earn about minimum of Rs. 50,000 per monthPowerPoint Presentation: More homogeneous and consistent cooking process minimum waste. Extrusion is a very efficient and clean process, since all steps can be done in-line: mixing, cooking, forming, cooling, and cutting. Modular designs allow changing from one product to another product, color, or shape to be done within minutes—a significant process efficiency. Twin-screw extruders are largely self-cleaning, an advantage from the viewpoint of both sanitation and labor savings. ConclusionExtrusion is a clean technology to deliver variety of designer & nutritionally balanced foods: Extrusion is a clean technology to deliver variety of designer & nutritionally balanced foods Thanks You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.