Browsing by Author "Watkinson P"

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    Effect of Process and Formulation Variables on the Structural and Physical Properties in Cream Cheese using GDL Acidulant
    (Springer Science+Business Media, LLC, 2022-06) Kim J; Watkinson P; Lad M; Matia-Merino L; Smith JR; Golding M
    We report on the properties of analogue cream cheeses prepared using glucono delta-lactone (GDL) acidulant, notably the impact of particular processing and formulation variables, (homogenisation pressure, coagulation pH and temperature, and stabiliser level) on cream cheese physical, material and microstructural properties. Protein–protein and protein-fat interactions were seen to be the primary structural contributors to the physical properties of cream cheese. Cream cheese microstructure and its properties demonstrated well-defined correlations to specific and controllable processing elements within the manufacturing process, showing significance in interactions between parameters in multivariable linear regression analysis (P < 0.05). Summarising the effect of processing variables on key cheese properties, we observed that a progressive reduction in fat particle size of cheese milk arising from increasing homogenisation pressures was seen to increase the total surface area of fat that could be incorporated into the curd during coagulation. The greater extent of fat-fat and fat-proteins interactions during coagulation provided a reinforcing effect on the microstructure of the final cream cheese, with a corresponding increase in compressive fracture stress, shear storage modulus (G′) and shear loss modulus (G″). In terms of other processing variables, cream cheese firmness was also observed to progressively increase through lowering of coagulation pH from 5.13 to 4.33. Increasing coagulation temperature from 58 °C to 78 °C similarly caused an increase in cheese firmness. Finally, increasing the levels of added stabiliser were shown to correlate with increasing cheese firmness. Similar correlations could be observed in relation to physical properties, notably forced expressible serum separation. This model cream cheese preparation method has provided a useful model system for relating food structure to material and functional properties. In addition, it has the advantage of being able to rapidly screen many formulation and process variables because it is faster than the traditional cheesemaking. This study showed that the adjustment of process and formulation variables, either in isolation or in combination, in the manufacture of cream cheese can significantly influence the final material and textural properties of the product, thereby enabling controllable functional attributes capable of meeting different customer needs.
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    Evaluation of formulation design on the physical and structural properties of commercial cream cheeses
    (John Wiley and Sons Ltd on behalf of Institute of Food, Science and Technology (IFSTTF)., 2022-10) Kim J; Watkinson P; Matia-Merino L; Smith JR; Golding M
    This study investigated how the compositional properties and formulation design of commercial cream cheese products model cheese influenced physical and structural properties as compared to a model cheese composition. Of the seven products evaluated, three were block format (B), two were spreadable (S) and two were spreadable light (SL), with fat contents ranging from 13.7 to 35.7%. The majority of cream cheese products indicated the inclusion of starter culture, and all formulations contained one or more stabilisers. Protein/moisture (p/m) ratio, i.e. the effective protein concentration in the non-fat substance, was seen to most strongly correlate with material properties, with a positive slope for fracture stress (R2 = 0.808) and modulus of deformability (R2 = 0.721). In terms of outliers, the datapoint for SL2 on this modulus versus p/m graph was lower than its regression line, and one rationale is that lower fat content (13.7%) gave a lower modulus from the milkfat component at 10°C test temperature. B1, with the highest p/m of 0.17, had a more dense distribution of larger fat globules coated with proteins than B2 and B3. Fracture stress and modulus of deformability were noted to be higher for full-fat than for lower fat cheese. In all products, elastic characteristics dominated viscous flow as expected. Findings have demonstrated that significant variance exists across the material properties of commerical cream cheeses, and which shows specific dependencies on their formulation.