Title: Texture and microstructure of low-fat and low-cholesterol panela type cheeses: different methodologies
Abstract: Three low-fat Panela cheeses were prepared from milk (13.5 g fat⋅L-1 milk) added with the following hydrocolloids: low methoxyl pectin (QPE), whey protein concentrate (QCP), and microparticulated whey protein (QPM). Additionally a low-fat Panela cheese was prepared from milk (6.75 g fat⋅L-1) incorporated with 6.1 g of emulsified canola oil in water⋅L-1 (QEM), and a low-fat Panela cheese was made from homogenized milk (13.5 g fat⋅L-1 milk) (QHM). As controls, a low-fat cheese (QBG) (13.5 g fat⋅L-1 milk), and a full-fat cheese (QCG) (27 g fat⋅L-1 milk) were prepared. After 48 h of manufactured, the different cheese treatments were subjected to chemical composition analysis, instrumental texture determination (Texture Profile Analysis), sensory texture evaluation (by a trained panel of judges), and microstructural analysis (Scanning Electron Microscopy). The QPE, QPM, and QEM cheeses had a relaxed, porous and open protein matrix associated with low values of hardness, springiness, cohesiveness, and chewiness; while the QBG and QHM cheeses showed a compact and dense protein matrix related with high values of hardness, springiness and chewiness. The QCP cheese presented instrumental textural characteristics comparable to those of the QCG cheese even though its protein matrix was apparently more compact and smoother than the corresponding to this latter. In general terms, the sensory texture characteristics correlated well with the instrumental textural characteristics.