Analysis of extensive experimental investigation indicate functionality of fillers in expanded snacks.
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Hard and soft fillers have different functionality, with only soft fillers contributing to crispiness.
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Absence of fillers, or many hard fillers leads to hard snacks with a coarse texture, which is less crispy.
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Final functionality of fillers during expansion depends on processing conditions during extrusion.
Abstract
Several starchy snacks differing in filler ingredients have been analysed regarding (1) the fate of filler ingredients during processing, and (2) the role of filler ingredients with respect to texture and structure. The structure has been characterized with X-ray tomography, and the texture has been evaluated via acoustic emissions from snack compression using a texture analyzer, which is assumed to be representative for crispiness. Our study shows that one has to distinguish hard and soft fillers. The absence of any filler or the presence of many hard fillers lead to a snack with a hard, coarse and non-crispy texture. However, if a significant amount of soft fillers is used then one attains a fine, and crispy texture.