3.2.2.2. Bulk density
Addition of 21% of pineapple pomace in the blends significantly increased (p ⩽ 0.05) the bulk density of the extrudates when compared with the control (Table 5). This result could be explained by the amount of fibre and sugar present in the PP. According to Dehghan-Shoar et al. (2010), these compounds have the capacity to absorb water, which can lead to products with increased density. Also, with the reduction in expansion of extrudates with fibre addition, an increase in density was expected, since more products could be compacted in a given volume. Similar effects were observed during extrusion with orange peel, grape peel, and tomato pomace (Yağcı & Göğüş, 2008). However, the lowest level of pomace addition (10.5%) did not affect (p ⩾ 0.05) the product density when compared to the control.