Snack innovation these days is all about using the newest, healthiest ingredients in the most unique ways. These snacks push the boundaries of flavor profiles and texture, which in turn test the limits of what equipment must do to produce these innovative, healthy snacks.
“The basics are corn, wheat, rice and oats, but these snacks could be made from things like pulses, lentils, beans, chickpeas or ancient grains like quinoa, teff or kamut,” said Michael Shaw, sales manager, North America, snacks and cereals extrusion, Bühler.
These out-of-the-box ingredients bring their own flavors, textures, hydration needs and challenges to the production floor. To handle these alternative snacks, producers look to extruders to turn out the latest in textures, shapes and ingredients.
“We understand how to include higher percentages of these healthier ingredients in the mix and still get the correct texture,” said Vince Pasquini, technical sales engineer, pretzel and snack, Reading Bakery Systems.
Managing the texture with these ingredients requires everything to come into play, he said: the right die and metering design, the correct tooling, the heat being put in the barrel.
“All the usual tools that any high-pressure extruder manufacturer might use — we’re coming at it from the same direction, just learning how to make the blends and how they react and how much flexibility you can have in those products,” he said.
While snack producers can employ several strategies and equipment innovations to make these doughs more consistent, produce more volume and result in a quality finished product, flexibility remains a top concern.
“Much of the innovation in this sector is driven by smaller companies,” said John McIsaac, vice-president, strategic business development, Reiser. “Many of the folks we see at our customer center and in their plants have unique ideas that have market appeal to certain segments: organic, vegan, gluten-free, nut-free, dairy-free, etc.”
Also, these smaller companies often produce a variety of different snacks in smaller quantities and, therefore, need equipment as nimble as they are at responding to trends.
Anticipating the curve
These healthier and alternative snacks start from doughs that don’t always cooperate with extruders the way conventional snack doughs do. Particularly, those without gluten don’t always have the elasticity necessary to make it through the extruder with the consistency and volume snack producers need.
“Forcing the dough through the extruder and into the augers without cohesiveness sometimes poses challenges,” Mr. Pasquini said.
To set these snack doughs up for success, Reading Bakery Systems developed its pre-feed extruder. This improves consistency of piece weight by positively feeding the extrusion auger. It avoids forming a dough column in the hopper.
“With the old technology, there were inconsistent weights of your product based on the height of the dough mass,” Mr. Pasquini explained. “When you filled the extruder’s hopper, you got a heavier piece weight. As the hopper emptied, piece weights would drop.”
The pre-feed extruder keeps such weight variations from happening.
Handtmann feeds dough consistently to extruders with the help of an infinitely adjustable vacuum level.
“Because such formulations are more dry or difficult to feed, we rely more on the vacuum to guarantee proper feeding and consequently consistent weights and shapes for the snack,” said Cesar Zelaya, bakery sales and technology manager, Handtmann, Inc.
Prepping the ingredients before the extruder is a strategy Baker Perkins adopted with its SBX Master pre-conditioner. This equipment mixes, hydrates and heats wet and dry ingredients with steam in a two-chamber system.
“Hydrating low-bulk-density ingredients in the preconditioner can greatly increase the volumentric fill, which may otherwise be quite low, leading to lower output,” said Keith Graham, marketing manager, Baker Perkins.
The first stage of the pre-conditioner is a high-intensity mixing phase that adds energy to the ingredients. The second allows that energy to equalize with moisture throughout the dough being formed, which not only enables snack producers to achieve the proper mix profile but also avoid clumping.
The hydration that happens in the pre-conditioner can also save on time with doughs made from these healthier ingredients.
“Multigrains and whole grains, pulses, vegetables and quinoa all have enhanced nutritional profiles compared with standard flours,” Mr. Graham explained. “Some, particularly those with high fiber, take longer to hydrate.”
By wetting out these ingredients in the pre-conditioner, snack producers can optimize cooking time and get the most output without having to extend the extruder barrel.
This feature can also save the equipment from being damaged by these ingredients. Some can be more abrasive than conventional ingredients, which causes excessive wear and tear to extruder screws and barrels and possible degradation of the nutritional content.
“Thermal energy input in the pre-conditioner replaces mechanical shear energy in the extruder, resulting in reduced wear and also avoiding protein damage in the product,” Mr. Graham said.
Pitching inclusion integrity
Inclusions have always posed a challenge to extruders. With these alternative ingredients, however, it’s important for visual appeal that they aren’t crushed.
“Maintaining particle size and appearance of some grains and inclusions used in healthy bars and snacks is a challenge for the baker or snack producer,” Mr. Zelaya said.
The key to handling such inclusions and the doughs that carry them is to do so gently, which Handtmann delivers with its extruding and cutting processes.
Reiser’s Vemag extruder transports product without smearing or crushing large particulates. While these doughs should be extruded gently, such particulate ingredients also must be fed to the extruder gently to keep them intact.
“Larger always seems to be better; visibility in the product is key,” Mr. McIsaac said. “Our Vemag’s unique system uses just the required amount of vacuum and mechanical force to load our double-screw, allowing processors to make their products according to their requirements, not the equipment’s requirements.”
Managing change-ups
In snacks these days, innovation is happening among the smaller players on the fringes of the industry. These companies do small runs of a variety of products instead of dedicating one line to one product. Innovation calls for a flexible line, one where a snack maker can quickly test a new product and adapt to its needs and then incorporate it into the plant’s production schedule.
“We often see producers who have a need to make multiple flavors and textures on a rotating basis to meet orders,” Mr. McIsaac said. “These often do not fit the normal criteria for sheeting and cutting lines, which are great for producing huge amounts of a single type of product. The folks who need to be flexible often look to extrusion.”
Flexibility is one of the inherent benefits of twin-screw extrusion.
“The benefit of the twin screw is the flexibility in adjusting the parameters — the screw speed, screw configuration, die design — to get to where you want to be,” Mr. Shaw said.
This allows snack producers to adjust not only to a wide variety of ingredients but also to variations within a single ingredient. If a formula uses an ingredient grown at a different time of the year or in a different climate or even when harvest conditions yield a good crop vs. bad crop, there could be different characteristics in the raw material, Mr. Shaw explained.
“You can adjust the twin screw’s parameters to compensate for variations and still produce the same quality snacks,” he said.
Gilles Maller, vice-president, sales and international for Clextral, also pointed out twin screw extrusion’s proclivity for adjusting to dough changes.
“Working with the twin-screw extruder offers advantages in this area as its inherent flexibility simplifies the work with minor ingredients,” he said.
Flexibility means quick, easy changeovers while maintaining weight accuracy, product quality and production speed. It can mean changing snack shapes and sizes or adjusting to fit variations in dough consistency.
Adding shape variation to its extrusion repertoire, Reiser developed the Vemag BC236 Ball Former that combines weight control with servo-controlled moving blades to make ball-shaped products and other variations to traditional snack bars. The company’s Vemag MMP223 high-speed cutting device enables snack producers to operate efficiently.
“This speed comes in combination with the great product integrity and weight accuracy of a Vemag double-screw system,” Mr. McIsaac said. “It gives snack producers the best of both worlds: high-speed production combined with flexibility.”
For ease of changeovers, Clextral introduced Clip-On modules for its extruders.
“These modules are designed to give snack processors flexibility to run different products on the same line,” Mr. Maller said.
The modules include a co-extruder for filled products, a crouton cutter for breadstick snacks, a chipstick cutter for french fry-style snacks, a bi-color/bi-flavor unit and an application system for sweet or savory coatings.
Reading Bakery Systems offers snack producers several auger designs to suit a variety of dough needs. Not only does the company offer multiple augers for snack producers to choose from, but they can also be changed out easily to handle different product characteristics from one dough to the next.
Extrusion allows snack producers to tackle the latest textures and shapes and go beyond the traditional potato chip. Today’s extrusion technology keeps up with the trendiest ingredients and gluten-free formulations by enabling proper dough prep, maintaining inclusion integrity and staying as nimble as the companies developing the products.
