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Hybrid fat blends have emerged as a promising approach to improve the properties of wax-based oleogels which can be used as healthier alternatives for saturated fat products such as butter and margarine. The application of wax-based oleogels is limited because of their sensitivity to shear and waxy mouthfeel. This research investigates the interaction between waxes and palm stearin in hybrid fat blends. For the oleogels, 150% of the critical gelling concentration of the waxes was used, specifically 6% berry wax (BEW), 1.5% candelilla wax (CLW) and 6% carnauba wax (CRW), all incorporated in rapeseed oil. The concentration of palm stearin (PS) in the reference system (30PS) and the hybrid fat blends was 30% (PS-BEW, PS-CLW, PS-CRW). It was found that the addition of PS to the wax-based oleogels largely affected the properties on the nano- to macroscale. On the nanoscale, the polymorphic transition from α to β of palm stearin was delayed when adding BEW, while it did not change with the other waxes. On microscale, the high melting CRW acted as a seeding template for the palm stearin in PS-CRW, resulting in the formation of fat crystals that were rich in CRW in the center. For PS-BEW and PS-CLW, it was hypothesized that the fat crystals were the result of co-crystallization. All three hybrid fat blends showed improved rigidity and shear sensitivity compared to the PS reference and the wax-based oleogels on a macroscale. These results demonstrate that the interaction between palm stearin and waxes can have a positive effect on the final structure. [ABSTRACT FROM AUTHOR]

Oleogelation is an alternative oil structuring route to formulate (semi-)solid fats with a reduced amount of saturated fats. Monoglycerides have been identified as effective gelators; however, their application potential can be limited due to challenges regarding mechanical strength and long-term stability. Therefore, the formulation of hybrid fat blends is a promising way to improve the functionality of oleogels. This research focuses on the interaction between mono- and triglycerides (MAGs and TAGs) in hybrid oleogels. A total gelator concentration of 10% (w/w) with changing MAGs–TAGs ratios (increase by 25% on a molar basis; M0-T100, M25-T75, M50-T50, M75-T25, M100-T0) was used. First, the oleogels were produced without shear to unravel the crystallization behavior (DSC, SAXS, WAXS). Next, the oleogels were crystallized with shear to assess the interactions between MAGs and TAGs on macroscale properties (rigidity, oil binding capacity) during storage of 1 day, 1 week, and 4 weeks. A clear distinction could be made between the MAG crystals and TAG crystals in the blends M50-T50 and M75-T25 based on WAXS, SAXS, and phase contrast microscopy. This indicates that both gelators crystallize separately. During the follow-up study of the dynamically produced samples, a synergistic effect was found for Dy-M50-T50 and Dy-M75-T25; however, it was not maintained upon storage. The initial rigidity of 2.4 × 104 Pa and 2.0 × 104 Pa decreased to 1.5 × 104 Pa and 1.0 × 104 Pa for Dy-M50-T50 and Dy-M75-T25, respectively. [ABSTRACT FROM AUTHOR]

Fat polymorphism plays a crucial role in many fat‐rich food products (e.g., margarine, chocolate). Due to this, polymorphism of triglycerides is widely investigated. During the previous years, the interest of using monoglyceride oleogels to replace margarine is increasing due to its structure, reduced amount of saturated fatty acids, stability and application potential. However, polymorphism of monoglyceride oleogels is less investigated. This research shows the effect of the composition (C18:0 or C18:0 and C16:0), temperature (25°C–20°C–10°C) and production process (static or lab‐scale scraped surface heat exchanger) on the crystallization behavior of monoglyceride oleogels (MO) by using differential scanning calorimetry, (synchrotron) X‐ray scattering and polarized light microscopy. Based on time‐resolved synchrotron WAXS, it was found that the rapeseed oil based MO (MO‐C18) occurred in four different polymorphs. During crystallization, transitions from an inverse lamellar phase (Lα) toward sub‐α1 and sub‐α2 could be established. Upon storage, a polymorphic transition toward β occurred. For the palm oil based MO (MO‐C18/C16), only two polymorphs were found during crystallization (Lα, sub‐α), followed by a polymorphic transition to β upon storage. By applying high shear and cooling rates during the production of MO‐C18 (dynamic production), the polymorphic transition from sub‐α2 to β occurred much faster compared to the static production method. When comparing the dynamically produced MO‐C18 and MO‐C18/C16, the thickness of 1 lamella, the crystal nanoplatelet and the fat crystals were smaller for MO‐C18/C16. This research clearly illustrates that the composition and the applied crystallization conditions have an impact on the properties from nano‐ to microscale. Practical Application: This research illustrates the importance of engineering monoglycerides oleogels to obtain food products with an improved nutritional balance. Hereby, the manuscript focuses on the crystallization behavior of monoglyceride oleogels by changing the composition and the crystallization procedure. The acquired insights go beyond the state of the art. It was found that applying high cooling rates and high shear rates by using a lab‐scale scraped surface heat exchanger affected the crystallization behavior of monoglyceride oleogels. These are crucial experiments to verify the application potential of monoglyceride oleogels in the food industry. Moreover, different polymorphic transitions occurred for the two types of monoglycerides. This is the starting point to investigate the effect of polymorphism on a final food product in order to improve the nutritional balance in fat‐rich food products. [ABSTRACT FROM AUTHOR]

Palm oil (PO) is still widely used for the production of all types of food products. Due to its triacylglycerol (TG) composition, PO is semisolid at ambient temperature, offering possibilities for many applications. In order to tailor the fat crystal network for certain applications, it remains imperative to understand the structural build-up of the fat crystal network at the full-length scale and to understand the effect of processing conditions. In this study, PO was crystallized under four temperature protocols (fast (FC) or slow (SC) cooling to 20 °C or 25 °C) and was followed for one hour of isothermal time. A broad toolbox was used to fundamentally unravel the structural build-up of the fat crystal network at different length scales. Wide-angle and small-angle X-ray scattering (WAXS and SAXS) showed transitions from α-2L to β'-2L over time. Despite the presence of the same polymorphic form (β'), chain length structure (2L), and domain size, ultra-small-angle X-ray scattering (USAXS) showed clear differences in the mesoscale. For all samples, the lamellar organization was confirmed. Both cooling speed and isothermal temperature were found to affect the size of the crystal nanoplatelets (CNPs), where the highest cooling speed and lowest isothermal temperature (FC and 20 °C) created the smallest CNPs. The microstructure was visualized with polarized light microscopy (PLM) and cryo-scanning electron microscopy (cryo-SEM), showing clear differences in crystallite size, clustering, and network morphology. Raman spectroscopy was applied to confirm differences in triglyceride distribution in the fat crystal network. This study shows that both cooling rate and isothermal temperature affect the fat crystal network formed, especially at the meso- and microscale. [ABSTRACT FROM AUTHOR]

Oleogelation offers the possibility to reduce the saturated fatty acid (SAFA) content while maintaining the desired organoleptic properties. Hereby, SAFAs are replaced by other structurants which can create a three‐dimensional network that immobilizes the liquid oil. Depending on the type of structurants, different structuring routes are identified. The use of monoacylglycerols (MAGs) as structurants is a promising approach thanks to their great self‐assembling properties. However, implementation into the food industry is still hampered due to insufficient characterization. This research includes a multiscale analysis of two dynamically produced MAG‐based oleogels (6% MAGs in oil, MO1 and MO2) as a function of the storage time (up to 8 weeks). Slight differences in the production process resulted in pronounced differences in techno‐functional properties of the MAG‐based oleogels. MO1 consisted of larger crystals, which resulted in a lower rigidity, reduced stability, and lower oil binding capacity compared with the other oleogel (MO2). On the nanoscale, it was found that the crystal nanoplatelets (CNPs) of MO1 contained a higher number of lamellae compared with MO2. Additionally, the results obtained with ultra‐small angle x‐ray scattering indicated a larger equivalent diameter for the CNPs of MO1. As a function of the storage time, both oleogels did not show major structural changes up to 8 weeks of storage. [ABSTRACT FROM AUTHOR]