Department of Food Science - Babcock Hall, University of Wisconsin-Madison, 1605 Linden Drive, Madison, Wisconsin, 53706, USA.
J Food Sci. 2020 Nov;85(11):3885-3898. doi: 10.1111/1750-3841.15486. Epub 2020 Oct 16.
Although the ice phase greatly influences the properties of ice cream, other structural components also affect its rheological behavior, particularly after melting. In this study, mix viscosity (serum phase viscosity), extent of fat destabilization (FD), and overrun were manipulated to produce different microstructures. The effects of these structural components were evaluated on the rheological properties of the ice creams and melted ice creams. In oscillatory thermorheometry, mix viscosity and then overrun, influenced G' and tanδ below -10 °C. When ice phase decreased (between -10 and -2.7 °C), mix viscosity had reduced effects, but continued to strongly affect G' and tanδ, followed by FD, and with lower effects from overrun. When the ice phase was completely melted at 0 °C, FD had most influence on G' and tanδ, followed by overrun, and with lower effects from mix viscosity. In creep/recovery test, six-element model described well creep behavior of melted ice cream at 0 °C. Viscous behavior at lower shear rate (η0 0 °C) was most influenced by mix viscosity, followed by FD, and lower overrun effects. In stress growth measurement, transient behavior, represented by σY 0 °C, of melted matrix at 0 °C was most influenced by FD, followed by mix viscosity, with lower overrun effects. In flow ramp measurement, Hysteresis Area was most affected by mix viscosity, followed by overrun, and with lower FD effects. Moreover, correlation between Hyst 0 °C and tanδ Peak suggested that structure formation affected the magnitude of tanδ Peak. These results document the importance of microstructure on properties of melted ice cream. PRACTICAL APPLICATION: The understanding of how structural components, such as mix viscosity, fat destabilization, and overrun, affect the ice cream matrix can help manufacturers to control its rheological behavior. The influence of these structural components on the G', tanδ, η , σ , and Hyst can be also used to understand the structural rearrangements that occur in meltdown tests and sensory analyses for future studies. Therefore, elucidation of these mechanisms on the rheological properties can directly assist in quality control and new product development in the ice cream industry.
尽管冰相极大地影响了冰淇淋的性质，但其他结构成分也会影响其流变行为，尤其是在融化之后。在本研究中，通过操纵混合粘度（血清相粘度）、脂肪失稳程度（FD）和膨胀率来产生不同的微观结构。评估这些结构成分对冰淇淋和融化冰淇淋的流变性质的影响。在振荡热流变学中，混合粘度，然后是膨胀率，影响了-10°C 以下的 G'和 tanδ。当冰相减少（-10 到-2.7°C 之间）时，混合粘度的影响降低，但仍强烈影响 G'和 tanδ，随后是 FD，而膨胀率的影响较低。当冰相在 0°C 完全融化时，FD 对 G'和 tanδ 的影响最大，其次是膨胀率，而混合粘度的影响较低。在蠕变/恢复试验中，六元模型很好地描述了 0°C 融化冰淇淋的蠕变行为。在较低剪切率下（η0 0°C）的粘性行为受混合粘度影响最大，其次是 FD，膨胀率的影响较低。在应力增长测量中，0°C 时融化基质的瞬态行为，由 σY 0°C 表示，受 FD 影响最大，其次是混合粘度，膨胀率的影响较低。在流动斜坡测量中，滞后面积受混合粘度影响最大，其次是膨胀率，FD 的影响较小。此外，Hyst 0°C 与 tanδ Peak 之间的相关性表明，结构形成影响了 tanδ Peak 的幅度。这些结果证明了微观结构对融化冰淇淋性质的重要性。实际应用：了解混合粘度、脂肪失稳和膨胀率等结构成分如何影响冰淇淋基质，可以帮助制造商控制其流变行为。这些结构成分对 G'、tanδ、η、σ和 Hyst 的影响也可以用于理解融化测试和感官分析中发生的结构重排，以便为未来的研究提供参考。因此，阐明这些机制对流变性质的影响可以直接协助冰淇淋行业的质量控制和新产品开发。
