Molding and extrusion process for imitation meat products and snack foods

The latest extrusion equipment can help food manufacturers to carry out various processing links such as styling, molding, extrusion and expansion of snack foods to produce a variety of products that dazzle consumers.

These extrusion equipment are not limited to processing pet food or children's snack foods. Extrusion equipment now produces a wide range of new products, including fortified foods.

Double-screw extrusion equipment has a long history, when consumers gradually accepted extruded food. The most classic history of this technology is General Mills' Bugles, which has achieved great success in the market. But it is only the lower-level product in the pyramid of food. If it is nutritionally considered, this kind of food is not worth mentioning.

Today, imagination has become a reality. Food producers have discovered that these exotic extruded foods not only have unique tastes and interesting appearances, but also provide nutrition and health to consumers. Extrusion foods currently on the market include shredded bread, baby food, pet food, high-fiber foods, sweets, puffed snack foods, spherical snack foods, ready-to-eat breakfast cereals, macaroni, cheese snack foods, ready-to-eat drinks and soups. Wait.

Focus on research and development

Starch content is critical for such extruded foods. Rice flour, potatoes, cassava, etc. can quickly swell after frying. Rice noodles have a very crisp taste. The starch content of corn is relatively low compared to the others, so the expansion rate is small. Extrusion foods processed with corn are harder and more brittle.

The expansion rates of wheat, oats, barley and other high-fiber cereals are also relatively small. They are the main raw materials for healthy snack foods and cereals. The extruded food processed with these raw materials is also hard and brittle.

When did you think of using these raw materials to process extruded food? The extrusion technology originally used to process pet foods and snack foods did not incorporate health factors.

The extruded foods using a plurality of raw materials are heated and pressurized after mixing, and then molded into a boiling pot, and are completely heated or partially heated. The final shape is formed when it is squeezed into the mold.

Double screw extrusion equipment is suitable for almost all processing shapes and materials. It can handle all kinds of raw materials with granules, humidity, fat content and carbohydrate content.

This type of extrusion equipment is highly adaptable and can help control capital and production costs. The double-screw extrusion equipment controls the various parameters of the machining process very accurately and can simultaneously perform multiple functions.

They are highly reliable and the quality of the products is stable. In addition, the products in the laboratory are almost identical to the production line and have excellent stability.

Imitation meat products

Extrusion equipment for protein or imitation meat products has attracted worldwide attention. The extruded food processed by this kind of equipment contains high-quality protein components, and the manufacturer can process all kinds of imitation fish meat products and pork products, and has good taste and convenient eating.

There are thousands of different formulations of extruded foods containing vegetable proteins. Soy protein is a vegetable protein raw material that is preferred by food processors because of its high flexibility and high edible value.

Doug Baldwin, director of sales and marketing at Wenger Manufacturing Inc. (), said, “The choice of protein source is the key to extruding food. It seems that the entire extruded food industry tends to be suitable for soy or other plants. protein."

Modified vegetable protein (TVP) is currently the most commonly used raw material in imitation meat products. Processors like to use this material because its texture is very close to that of fleshy fiber.

“High-humidity raw meat products do not need to be dried,” Baldwin said. “After processing through the production line, the humidity is as high as 70%. As long as it passes through the extruder, it can get very close to the texture of the chicken breast slices.”

Archer Daniels Midland () last year introduced a high-humidity imitation meat product called "Nutrisoy Next", a ready-to-eat product.

Cheryl Borders, manager of the company's soy foods division, said, "Improved vegetable protein (TVP) is an improved technology for improving defatted soy flour (ADM). ADM uses a single-screw technology, and the product humidity is low, only 35%. And the humidity of our new product. The range is 50%-80%, the taste is different, and the humidity is different."

A new generation of imitation meat products is easy to eat and of higher quality. They have many options for structural modeling, strips, blocks, cubes, fragments, cold food, and cooking. Compared with the original imitation meat products, the new generation of products tastes better. Although there is also beef or pork flavor and taste, the poultry meat products are still the core products.

“You can also add a variety of flavors to low-moisture extruded meat products, but the product loses a lot of flavor when it leaves the extrusion equipment because of the pressure drop,” Borders said. “And high-humidity products have less pressure drop, The product leaves the extrusion equipment and enters the cooling mold. The temperature change increases the viscosity of the product, which helps to improve the texture of the product."

The processing of such products includes the use of cooling molds, which have been used for decades. "But in fact, the advancement of the double helix technology is not big," Borders said. "74% of consumers think that soy food is good for health. Nowadays, they accept such products and start to look forward to the launch of new products."

Double helix advantage

Double-screw extrusion equipment has gradually replaced single-screw equipment. Single-screw equipment is currently mainly used for the processing of animal feed, which has rarely been used in human food.

As early as the 1950s, producers began pre-conditioning raw materials for food extrusion. "And this technology has only matured in recent years," Baldwin said.

The scale of technical equipment is mainly expressed by the length-diameter system, specifically the length of the barrel and the diameter of the spiral. “We have been able to shorten the length of the barrel to reduce the hardware requirements,” added Baldwin.

“We try to use heat and reduce mechanical energy,” Baldwin said. Energy consumption is one of the most concerned issues for manufacturers today. “Using thermal energy processing is more economical than mechanical energy. If you can reduce the use of steam in preconditioning, you can reduce the use of horsepower in cooking.”

Clextral Inc. () is the first company to use twin-screw extrusion equipment for food processing. At present, the company emphasizes the modular concept, faster switching time, and reduced use of spirals, barrels and molds. The newly designed equipment is healthier and faster. These practical design concepts make the position of the twin-screw extrusion equipment more stable in the minds of users.

“Our twin-screw equipment switches between different spirals very quickly and is easier to clean,” said Laurent Garcia, director of sales at the company. “Spiral repair and replacement can be done in 5 minutes. Users can observe all corners of the entire device and find where the starch is agglomerated.”

Better temperature control and automation technology help improve product quality and stability while increasing equipment flexibility. “If you need to process new products, you only need to adjust the parameters of some extrusion equipment. You can process new products by adding a little auxiliary equipment to your equipment,” Garcia said.

Double screw extrusion equipment can process a variety of raw materials, colors, tastes and textures.

“We were the first producer to develop broken bread with a layer of sugar in the middle, using coextrusion technology,” Garcia said. “You can also add chocolate, jam and other fruit-flavored bread hearts.”

Snack foods and ready-to-eat cereals are currently the most widely used types of extrusion equipment, and Garcia is more concerned with health foods, especially in the low-carbon and modified protein markets.

Snack foods

Extrusion equipment is suitable for a wide range of raw materials, which greatly expands the range of snack foods. In Asia and the Middle East, many consumers like spherical snack foods.

This phenomenon may be analyzed from an economic perspective. The mixed raw material of the spherical snack food comes out of the cooking extruder, and the humidity is relatively small.

The processing equipment puffs the pellets and heats them with hot oil, microwaves or hot air.

What is the future trend?

There will be a large market for low-carbon extruded snack foods, and the sales of soy meat products processed by soy protein raw materials are also very promising.

Casual food giant Frito-Lay's Cheeto squeezed snack food won a gold medal. The company develops its own extruded foods, and Cheeto is the company's latest product.

The company recently launched a Baked Cheetos product, a healthy snack food.

At present, the development prospect of imitation meat products is very promising. It has healthy raw materials and charming flavor. However, due to the high cost of high-quality imitation meat products, these products are still high value-added foods.

As the extrusion technology has become more and more sophisticated, the imitation meat products developed with this technology have achieved the effect of realism.