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Water‐in‐oil‐in‐water (W/O/W) double emulsions present a reduced‐fat alternative to conventional O/W food emulsions, as part of the dispersed oil phase is replaced with water. In this study, the concept of a reduced‐fat whipped topping produced by W/O/W technology was proven. Whipping of a W/O/W emulsion, containing only 20% oil phase and a solid fat content of 78%, produced a superior whipped topping, in terms of firmness and overrun, compared to its whipped O/W emulsion counterparts. The presence of PGPR in the oil phase increased structure formation during whipping, while the additional dispersed‐phase volume resulted in a better air inclusion. Two commercial monoacylglycerols (saturated and unsaturated) were investigated to improve the whipping properties of the produced W/O/W double emulsion. Both increased the susceptibility towards partial coalescence, thereby reducing whipping time and overrun, while increasing firmness of the produced whipped topping. Furthermore, the effect was stronger for the unsaturated than for the saturated monoacylglycerol.

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.

Water-in-oil-in-water (W/O/W) technology enables the development of an emulsion-based delivery system for functional food applications. The functionality of this system depends on the oil barrier of the double emulsion, whereby the fat matrix properties (e.g. solid fat content) play an important role. First, the effect of W/O/W emulsification on fat crystallization and melting behavior was studied and compared to bulk fat. Second, the effect of fat composition was investigated. As such, W/O/W emulsions were produced with a slow and fast crystallizing fat, i.e. soft palm mid fraction (sPMF) and partially hydrogenated sunflower oil, respectively, upon cooling and subsequent isothermal crystallization. Low resolution NMR and DSC techniques were applied, and indications about the polymorphic behavior were verified by real-time synchrotron XRD measurements. Except from increased supercooling, the overall fat crystallization dynamics in the W/O/W emulsions were similar to bulk, irrespective of the used fat. Yet, broadening of the long spacing peaks in the W/O/W emulsions indicated less ordered triacylglycerol longitudinal stacking compared to bulk. This effect was more pronounced in case of α-crystals than β’-crystals. With respect to W/O/W functionality, the melting behavior of the W/O/WsPMF emulsion showed promise as a possible carrier system with a thermo-responsive release mechanism for functional foods.

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.

The influence of tempering (i.e., successive heating and cooling) on crystallization properties of semicrystalline milk fat-in-water emulsions was studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and cryoscanning electron microscopy. Melting profiles obtained by DSC indicate a fractionation process of milk fat in every individual fat droplet. The long spacings, as observed by XRD, were useful in the designation of polymorphic changes to a shift in fatty acid composition of the crystals. An increased layer thickness of the 3L-crystals at 20 and 30 °C tempering points to a preferential incorporation of long-chain unsaturated fatty acids over short-chain fatty acids. Additionally, at 30 °C, an increased layer thickness of the 2L-crystals assumes the incorporation of longer-chain saturated fatty acids. The highly mixed crystals, an inherent property of milk fat, seem to be fractionated in purer crystals grouping triacylglycerols with a similar fatty acid composition. Moreover, a di...

Systems containing monoacylglycerols (MAGs) in both a hydrophobic solvent (liquid oil) and a hydrophilic solvent (water) can be used for the development of calorie-reduced food products. In this study, the crystallization behavior of MAGs in a hydrophobic solvent (rapeseed oil) and a hydrophilic solvent (water) was studied and compared. Pure monopalmitin (MP) and a commercial MAG containing MP were used for this study. Differential scanning calorimetry (DSC) data were coupled with X-ray diffraction (XRD) data obtained using synchrotron radiation and cryo-scanning electron microscopy (cryo-SEM) images were recorded to illustrate the microstructural characteristics of the systems. Although the polymorphic behavior of the MAGs was found to be the same in both solvents, the crystallization onset temperature was found to be concentration-dependent in the systems with liquid oil as solvent, in contrast to the systems with water as solvent. On the other hand, the temperature of the polymorphic transition from the α to the sub-α polymorph was constant in both systems. Differences in microstructure could be attributed to the inherent properties of the hydrophobic or hydrophilic solvent.

Milk fat globule membrane (MFGM) fragments were isolated from reconstituted buttermilk (BM-MFGM) and from buttermilk whey (whey-MFGM) and used to make recombined cream. Lacprodan®PL20 was used as another MFGM source. The effect of MFGM on the shear-induced partial coalescence and on the whipping properties of recombined cream was investigated and compared with those of natural cream and recombined cream made with buttermilk powder (BMP). Recombined cream was prepared by homogenising 35% (w/w) anhydrous milk fat into an aqueous phase containing individual BM-MFGM, whey-MFGM, Lacprodan®PL20, or BMP or a mixture of MFGM materials and BMP (4:6, w/w). Recombined cream made with a mixture of whey-MFGM and BMP showed improved whipping properties, namely high overrun, no serum loss and reasonable firmness. Shear-induced partial coalescence of whey-MFGM40 was slower compared with that of natural cream. Data indicated that a mixture of whey-MFGM and BMP can improve the whipping properties of the recombined cream.

The influence of unsaturated (rich in oleic acid, MAG-O) and saturated (rich in stearic acid, MAG-S) monoacylglycerols on the shear-induced partial coalescence and on the whipping properties of recombined cream was studied at different concentrations. MAG-O reduces the churning time and the whipping time, lowers the overrun and serum loss and increases the firmness of the whipped cream. The exact opposite effects were observed upon the addition of MAG-S. Protein load analyses, interfacial tension measurements and interfacial rheology experiments were carried out to elucidate the mechanism behind the diverging effects of these monoacylglycerols. The long-chain saturated MAGs behaved as a solid at the oil–water interface while its unsaturated counterpart appeared to be in the liquid state. The occurrence of chain crystallization and subsequent interfacial heterogeneous nucleation appeared to play a decisive role in the stability of RCs towards partial coalescence.

The effect of monoacylglycerols (rich in oleic acid, stearic acid or lauric acid) on milk fat crystallization in recombined cream is examined using differential scanning calorimetry to study crystallization kinetics, nuclear magnetic resonance to measure solid fat content during storage and interfacial tension analyses to analyze interfacial properties. The long-chain saturated monoacylglycerols (stearic acid) form upon cooling a two-dimensional crystal at the interface, called chain crystallization, which induces interfacial heterogeneous nucleation. Also, the crystal growth and α–β′ polymorphic transition were accelerated. On the contrary, long-chain unsaturated monoacylglycerols (oleic acid) didn't affect the crystallization behavior while mid-chain saturated monoacylglycerols (lauric acid) showed intermediate behavior. None of the monoacylglycerols influenced the solid fat content after storage for 5 days at 5 °C. The observed differences in nucleation mechanism and crystallization kinetics may influence the microstructural arrangement of the milk fat inside the fat globules and consequently the partial coalescence rate and hence the whipping properties of recombined cream.

A refining step is often crucial for the removal of undesired components in fats and oils. More flexible refining technologies are required due to a global decline in cocoa butter quality and to meet industry’s demand for cocoa butters with improved properties. The aim was to investigate the impact of the cocoa butter refining process on milk chocolate quality. Therefore a crude cocoa butter was subjected to a steam refining at different temperatures and this with or without a silica pretreatment. The major effect of the silica pretreatment was the complete removal of phosphorus (thus phospholipids), iron and alkaline components. During the steam refining step mainly Free Fatty Acids (FFA) were removed at increased temperatures (T ⩾ 200 °C). The refining of the cocoa butter influenced the rheological properties of the chocolate. An increased packed column temperature, coinciding with the removal of FFA, resulted in a lower yield stress and a higher viscosity. Reduction of FFA positively influenced the crystallization kinetics and the formation of the crystal network, resulting in differences on a macroscopic scale.