No abstract

The impact of high pressure homogenization (HPH) on physical characteristics and emulsion stability of nutritional formulations were evaluated on a pilot scale HPH unit. Two products of industrial interest were used for these experiments. Manufactured formulations were analyzed using material characterization methods as particle size distribution, microscopy and dynamic mechanical spectra, compared to a control formula manufactured with conventional homogenization and heat treatments. Dynamic rheological measurements as strain and frequency sweeps exhibited increased product stability in parallel to increased homogenization pressures. Homogenization at elevated pressures yielded more shear thinning fluids evidenced by increased viscosities at low shear rates, ten fold greater compared to the control treatment, further evidence to increased physical stability. Experimental findings revealed the existence of a threshold pressure (100-150 MPa) for both formulations exhibiting significant correlation with product quality and physical stability. The study outcomes presents an opportunity for reducing stabilizer concentration in dairy beverages; in addition to shelf life and physical stability improvement for formulations treated at increased homogenization pressures.

Summary Low‐fat Cheddar cheese was manufactured using a β‐glucan, hydrocolloidal fat replacer denoted as Nutrim. The composition, production efficiency, microstructure, and utility of replacing fat with Nutrim were examined. Cheese samples (designated as Nutrim‐I, and Nutrim‐II) containing Nutrim were produced with mean fat levels of 6.84 and 3.47%, respectively. A low‐fat cheese was also produced as a control with a mean fat level of 11.2%. Nutrim‐II cheese had significantly higher moisture, salt, and ash contents as compared with the low‐fat control cheese. The low‐fat control cheese had a higher yield normalized for 54% moisture and 1.5% salt content as compared with the Nutrim‐II cheese. Scanning electron microscopy revealed smaller and more uniform fat droplet voids in the Nutrim cheese than the low‐fat control, and a more dense, noncontinuous background protein matrix with globular clusters suggesting a physical buffering afforded by the presence of the β‐glucan hydrocolloid or its associated water.