The food major said there was need to develop such products for consumers looking to eat lighter, more distinctive snacks while at the same time continue to use standard equipment and easily upscale.
Nestlé said that by combining cold extrusion – preferably with a twin extruder – and puffing the product in a conventional or electric oven, it was able to develop thin shelled snacks resistant to breakage and deformation.
“It was surprisingly found that by carrying out the extrusion process under low temperature and pressure conditions and then subsequently heat treating the products in an oven gave substantially puffed products endowed with unique texture and properties,” it said in its global patent filing.
“…Without wishing to be bound by theory, it is believed that the very low temperature and pressure conditions used in the extrusion phase create a unique stage of starch gelatinization in the dough which enables said puffing during subsequent oven treatment,” it continued.
The method, it said, could be used to puff any dry starch mix, from modified cereals and legume starches to wheat flours and others like buckwheat, rice and barley.
Light but strong
Typically, Nestlé said puffed products were extruded under high temperatures and pressure – puffed immediately at the extrusion stage.
However, it said such methods meant snacks were vulnerable to breakages, particularly when packed using flexible packaging.
“Light puffed snacks are anyway often associated with an intrinsic fragility which causes them to break or deform when stored or transported in flexible packaging. Accordingly there is still a need to provide puffed hollow snacks which, despite having low density and being characterized by a thin shell, show resistance to breakfast and/or deformation when packed,” it said.
Nestlé said the snack shells made using its method, however, had “surprising” resistance despite a typically lower shell thickness and product density.
Nestlé said the resulting puffed snacks could be coated or further fried if a manufacturer wished to do so – adding sweet coatings like chocolate or caramels or savory like bread crumbs or nut pieces.
Source: WIPO Publication No. WO2015091517
Published: June 25, 2015. Filed: December 16, 2014.
“Method for manufacturing puffed hollow snacks”
Authors: Nestlé – R. Farber-Oron, A. Tslaf, DJ. Kraus and HMJ. Chanvrier