In the margarine and butter industry, sustainable and more efficient refrigerants, such as CO2, are introduced to industrial scraped surface heat exchangers, allowing an increased capacity compared to conventional use of NH3. The effect of such changes in capacity and a varied rotational speed was studied in relation to the structural behavior of puff pastry butter during 4 weeks of isothermal storage at 20 °C. The physical properties of the fat crystal network were studied in detail at several length scales by combining X-ray diffraction with differential scanning calorimetry, confocal laser scanning microscopy, LR-NMR and rheology. Our data shows that a high capacity combined with high rotational speed decreases the brittleness of puff pastry butter after 7 days of storage. This effect is, however, diminished after 28 days of storage. Likewise, changes in capacity and rotational speed are shown to induce no microstructural and polymorphic differences after 28 days of storage. However, the degree of work softening is related to the manufacturing conditions: a high capacity and a high rotational speed increase the ability of the puff pastry butter to resist structural breakdown during working. With this being the only observed difference; a wide operational window exists on an industrial level to produce puff pastry butter with similar structural behavior.
KEYWORDS: Crystal size, Food