Pomegranate seed oil organogels structured by propolis wax, beeswax, and their mixture

Abstract

The capability of propolis wax, beeswax, and their mixture to gel pomegranate seed oil (PSO) was studied. Samples were prepared increasing the concentration of waxes in pomegranate seed oil from 5 to 15% w/w. After propolis wax, beeswax, and PSO chemical characterization, thermal, and structural properties of wax-based organogels were studied. Both propolis wax and beeswax formed organogel thanks to the presence of crystal networks made of needle-like β′-form crystals. Based on FTIR spectroscopy, mainly van der Waals interactions were formed in the systems. Propolis wax organogels displayed lower firmness and G′ and G″ modulus in comparison to the corresponding beeswax samples. This was due to the presence of larger crystals with a less organized network. The observed behaviors were attributed to differences in chemical composition between these two types of waxes. The combined use of propolis wax and beeswax led to organogels with behavior in between the organogels with single waxes, probably as a consequence of the formation of mixed crystals. Practical applications: Pomegranate seed oil (PSO) with considerable amounts of polyunsaturated fatty acids can be convert into structured systems by oil gelation as a novel strategy to delivery it in a system that allows its incorporation in the food matrix. The obtain data acquired in this research highlight that propolis and bees waxes and their mixture can be considered as good gelators of PSO. The final structure of the organogel can be tailored by selecting the organogelator and its concentration in the use of fat based alternative in food products need β′-form crystals such as spreads and margarines. The aim of the present research is to develop pomegranate seed oil (PSO) organogels by using beeswax, propolis wax, and their mixture. Organogels are characterized by using different techniques, including polarized light microscopy (PLM), Fourier transform infrared (FTIR) spectroscopy, DSC analysis, synchrotron X-ray diffraction, rheology, and mechanical properties. In accordance with findings, both propolis and bees waxes can be considered as good gelators of PSO. Depending on intended food application, the final structure of the organogel can be tailored by selecting the organogelator and its concentration

Wax‐based delivery systems: Preparation, characterization, and food applications

“…Similar observations were also reported by Morales-Rueda et al (2009) studying CLW crystal network in sunflower oil and Sánchez-Becerril et al (2018) studying CLW crystal network in high-oleic safflower oil. In agreement with other literatures, Fayaz, Goli, Kadivar, Valoppi, Barba, Balducci, et al (2017) reported needle-like crystals of BW and PW oleogels in which the BW organogel contained smaller crystals than PW sample.…”

“…In the Yılmaz and Öğütcü (2014a) study, olive oil organogels of BW and SW exhibited very similar XRD pattern and the main peaks were at 4.1 and 3.7 A˚, related to the orthorhombic perpendicular subcell. Similar pattern implicating this polymorph has been observed for CRW, CLW, and RBW gels with olive oil (Dassanayake et al, 2009), SW, CRW, and BW gels with hazelnut oil (Öğütcü & Yılmaz, 2015;Yılmaz & Öğütcü, 2014b), PW, and BW gels with PSO (Fayaz, Goli, Kadivar, Valoppi, Barba, Balducci, et al, 2017), and canola, sesame, sunflower, and flaxseed oil oleogels of PW . This polymorph with desirable attributes (homogeneous, smooth and creamy) can be used as a partial replacement for hard fat in products such as shortening, margarines, and spreads that need β′ polymorph of triglycerides .…”

“…Doan et al (2015) reported that anisotropic rod-like crystalline particles of SW facilitate gel formation at much lower concentrations, while berry wax forms large spherical crystals leading to gel formation only at high concentrations. Similarly, long needle-like structures of BW and PW formed good crystalline matrices, capable of entrapping large amounts of liquid oil in the network (more than 90% OBC; Doan et al, 2015;Fayaz, Goli, Kadivar, Valoppi, Barba, Balducci, et al, 2017). However, Blake et al (2014) reported that despite spherical morphology, CLW exhibited superior OBC than RBW.…”

Structure and stability of edible oleogels prepared with different unsaturated oils and hydrocolloids

“…The loss of the flaxseed oil during the rheological measurement could be the reason of a more compact network oleogel with higher G’ value. Oleogels presented similar values to others prepared with 5–15% beeswax, propolis wax, a mixture of both (Fayaz et al , ), with a combination of 5% ethylcellulose (EC) and 5% surfactant (Gallego et al , ).…”

Exploitation of high‐intensity ultrasound to modify the structure of olive oil organogel containing propolis wax

“…Based on our previous researches, propolis wax was identified as an efficient structuring agent for organogel formation and displayed the potency to apply as a partial replacement of fat phase in chocolate spread (Fayaz et al, 2017a,b). To modify the organogel behavior, mixture of beeswax and propolis wax was suggested (Fayaz et al, 2017c). In this study, we aimed to improve crystal structure and thermal properties of propolis wax-based organogel using powerful method of HIU.…”