Abstract
In this study, bigels were developed to mimic the characteristics of traditional laminating fats, butter and margarine, in croissants. The bigels consist of 80 % oleogel (canola oil, wax and monoacylglyceride) and 20 % hydrogel (water and xanthan gum). Beeswax (BW), carnauba wax (CBW), candelilla wax (CLW), and rice bran wax (RBW) were evaluated as oleogelators at concentrations between 12 and 20 % w/w in the oleogel. The effects of wax concentration, temperature, and mechanical work (plasticizing) on texture, solid fat content, and microstructure of the bigels were investigated. Bigels' solid fat content and mechanical properties were less temperature sensitive than controls, but mechanical work (plasticizing) had detrimental effects on their texture. Differences in bigel firmness between waxes at the same concentration could be attributed to different wax crystal structures. Plasticized bigels most similar in texture to the controls were those with 18 % BW, 14 % CBW, 14 % CLW, and 20 % RBW. These bigels were tested as laminating fats in croissants at 100 % replacement levels. After lamination, the croissant doughs with bigels exhibited irregular fat layering, resulting in more dense and less airy croissant pore structure. While bigel croissants possessed a comparable volume, they were generally flatter and wider compared to croissants with control fats. In terms of texture, bigel croissants displayed a lower degree of staling, but had overall higher firmness. Furthermore, they had similar springiness and cohesiveness, but increased chewiness. With respect to nutritional value, croissant made with bigels contained significantly less saturated fatty acids.