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The presence of a fat crystal network throughout the fat droplets of an oil-in-water emulsion is a requisite for partial coalescence. The characteristics of this fat crystal network determine greatly the kinetics of partial coalescence. In this study the fat crystal network was manipulated by altering the cooling rate applied to natural cream. The kinetics of partial coalescence under constant shear and at constant temperature were studied by combining rotational viscosity analysis with light microscopy and laser scattering. It was shown that slow cooling of the emulsion decelerates partial coalescence and favors the formation of loosely-packed aggregates. On the other hand, fast cooling favors a high partial coalescence rate and the formation of dense aggregates. Fat crystallization properties were analyzed using small deformation rheology, differential scanning calorimetry and cryo-scanning electron microscopy. The difference in organization of the fat crystals obtained for both cooling rates contributed significantly to the mechanistic understanding of partial coalescence as influenced by the cooling rate.

Diacylglycerols (DAGs) are interesting oil structuring molecules as they are structurally similar to triacylglycerols (TAGs), but are metabolized differently which results in weight loss and improved blood cholesterol levels upon dietary replacement of TAGs with DAGs. Many commercial products consist of a mixture of monoacylglycerols (MAGs) and DAGs, yet the effect of MAGs on the crystallization behavior of DAGs is still to be unraveled. Two types of commercial MAGs, one originating from hydrogenated palm stearin and one of hydrogenated rapeseed oil, were added in concentrations 1, 2 and 4% to 20% DAGs derived from hydrogenated soybean oil. Using differential scanning calorimetry, it was shown that the presence of MAGs delayed the onset of DAG crystallization. Rheological analysis revealed that MAGs also hindered crystal network development. Synchrotron X-ray diffraction analysis demonstrated that the addition of MAGs suppressed the formation of the β form and stimulated the development of the β' form. Likely, MAGs mainly hindered the crystallization of 1,3-DAGs, which are responsible for the development of the β form, and stimulated the crystallization of the 1,2-DAGs, which can crystallize in the α and β' forms. The presence of two polymorphic forms resulted in a decrease of the crystal network strength, as was derived from oscillatory rheological measurements. This research implies a different effect of monoacylglycerols on both the nucleation and crystal growth of 1,2- and 1,3-DAG isomers. This insight is not only relevant for oleogelation research, but also for emulsifying agents which often contain blends of MAGs, 1,2-DAGs and 1,3-DAGs.

Emulsion stability is desired during production, storage and transportation. However, controlled destabilization by partial coalescence is requisite in the production of e.g. whipped cream, vegetable toppings and ice cream. Partial coalescence in recombined cream (RC) implies the presence of a semisolid fat. Three types of fat, i.e. anhydrous milk fat (AMF), palm oil (PO) and palm kernel oil (PKO), were used in the production of RC. Partial coalescence was initiated by the application of shear and assessed at three temperatures, namely 15, 20 and 25 °C to investigate the relation between solid fat content (SFC) and shear-induced partial coalescence. Despite differences in SFC, shear-induced partial coalescence occurred fastest at 20 °C. On the contrary, a nearly equal SFC at 25 °C resulted in significantly different behavior amongst the fats. This demonstrates that not only SFC determines instability but also fat crystal microstructure, which is dependent on fat composition and on processing conditions. However, SFC could be related to the type of network formed by the partially coalesced fat droplets. The fat crystallization properties, studied in bulk and emulsion, point out a divergent effect of emulsification on the crystallization of the fats which could be explained by differences in crystal morphology.

Ultraviolet (UV) and infrared (IR) treatments were conducted to reduce anti-nutritional factors of 5-day germinated soybean. Exposure time/duration and distance/height to UV/IR were 24/48/72 h for UV treatment at 7/17/27 cm distance and 1.0/1.5/2.0 h for IR treatment at 15/20/25 cm distance. These resulted in significant reductions (P

There is a growing interest in non-genetically modified, healthy snacks. Soy snacks are available on the market but snacks from germinated soybean are limited. The objectives of this research were to germinate non-genetically modified soybeans, analyze their physicochemical and nutritional characteristics, and develop a prototype snack chip. Moisture, protein, and lipid contents of flours from soybeans germinated for 1, 3, or 5 d ranged from 2.4 to 5.3, 42.7–43.3, and 21.4–25.5 g/100 g respectively (P > 0.05), while lipoxygenase-1 and lipoxygenase-3 activity, and trypsin inhibitor reductions ranged from 2.8 to 17.2, 16.2–26.1, and 16.6–31.1% and estimated glycemic indices ranged from 12.1 to 19.5. These reductions and estimated glycemic indices showed significant differences among the germinated soybeans (P

This study investigates the effect of applying a time–temperature profile to natural and recombined cream to influence partial coalescence and, consequently, the whipping quality. To date, no clear relationship exists between the consequences of tempering on a microstructural level, partial coalescence, and whipping properties. Milk fat crystallisation was analysed using differential scanning calorimetry and the internal arrangement of fat crystals was visualised with cryo-scanning electron microscopy. Shear-induced partial coalescence and whipping properties were studied. Shear-induced partial coalescence was promoted, attributed to the observed changes in the fat crystal network. The effects on whipping properties were different for natural and recombined cream and thus dependent upon the interfacial composition. Consolidation of the partially coalesced fat droplet network by tempering increased the stability of whipped recombined cream during cold storage. Tempering is a promising tool to alter the susceptibility to partial coalescence by changing the internal fat crystal network, and influencing whippability.