Effect of processing conditions as high‐intensity ultrasound, agitation, and cooling temperature on the physical properties of a low saturated fat

Abstract

The objective of this work was to evaluate the effect that agitation rate, crystallization temperature, and sonication have on the physical properties of a soybean-based fat with low levels of saturated fatty acids crystallized in a scraped surface heat exchanger (SSHE). The sample was crystallized at two temperatures (20 and 25°C) and agitation rates (344/208 rpm in the barrels/pin worker-high agitation HA and 185/71 rpm barrels/pin worker-low agitation LA), and a constant flow of 11 L/hr. High-intensity ultrasound (HIU-12.7 mm-diameter tip, 50% amplitude, 5 s pulses) was coupled to a water jacketed flow-cell and placed at three different positions within the SSHE. The combination of all those parameters affected samples' physical properties. Higher oil binding capacity (OBC) and elasticity (G') were obtained at 20°C compared to 25°C (77% vs. 63.78% for OBC and 30.4 kPa vs. 6 kPa for G', respectively) due to the smaller crystals formed at 20°C. Fewer or no differences were observed due to agitation alone, but LA conditions allowed for more secondary nucleation to form due to sonication and resulted in a higher improvement on the properties of the fat.

Relationship between oil binding capacity and physical properties of interesterified soybean oil

“…The presence of these many small crystals could have increased the hardness for samples with the same SFC due to the small crystals forming a tighter, more uniform crystal matrix compared to large crystals. Similar results were found by other authors (da Silva, Cooper, et al, 2020;da Silva, Danthine, & Martini, 2020;Kerr et al, 2011;Suzuki et al, 2010;Wagh et al, 2013;Ye et al, 2011;Ye & Martini, 2015), where the application of HIU resulted in smaller crystals, no differences in SFC, and harder materials.…”

“…Oil loss OL was measured using a centrifuge method previously described in other studies (da Pieve et al, 2010;da Silva, Cooper, et al, 2020;da Silva, Danthine, & Martini, 2020;da Silva, Marsh, et al, 2020;Giacomozzi et al, 2019). Approximately 1 g of the sample was placed in a pre-weighed microcentrifuge tube, placed in a centrifuge, and spun for 15 min at 10,000 rpm.…”

“…Oil migration is determined by the fat's oil binding capacity (OBC) which describes the ability of the fat matrix to entrap liquid oil, therefore, preventing oil migration from occurring. The OBC of fats can be influenced by processing conditions including cooling rate (Dibildox-Alvarado et al, 2004), shear (Acevedo et al, 2012a(Acevedo et al, , 2012b, and high-intensity ultrasound (HIU) (da Silva, Cooper, et al, 2020;da Silva, Danthine, & Martini, 2020;da Silva, Marsh, et al, 2020). OBC can also be influenced by the chemical composition of the samples such as the type and concentration of triacylglycerols (TAG) (Ghosh et al, 2002).…”

A review of the use of scraped surface heat exchangers to crystallize fats and fat‐based products

“…The abbreviation HIU‐0 is used when HIU is placed before the first barrel, HIU‐1 corresponds to having HIU between the two barrels, in HIU‐2 the HIU is placed after the second barrel (and before the PW), and HIU‐3 indicates that the HIU is placed after the PW when crystallization in the SSHE is completed (da Silva & Martini, 2019). These studies found that the induced sonocrystallization was affected by the chemical composition of the lipid used (da Silva et al, 2021a; da Silva, Danthine, et al, 2020) and by sonocrystallization conditions (da Silva & Martini, 2019) as observed in a batch condition. Nevertheless, SSHE crystallization conditions also played an important role, such as (1) Step of crystallization where HIU is applied (HIU‐0, HIU‐1, HIU‐2, and HIU‐3).…”

“…Recent innovations in the use of SSHE have also been reported, mostly combining SSHE crystallization with other equipment such as high-intensity ultrasound (HIU), high-pressure homogenizer, or other crystallization units. For HIU, authors have induced crystallization and improved physical properties of different fats by coupling the HIU in different stages of the SSHE (da Silva et al, 2021a(da Silva et al, , 2021bda Silva, Danthine, et al, 2020;da Silva & Martini, 2019;da Silva & Martini, 2020a, 2020b. SSHE has also been coupled in a double-stage homogenizer (DSH) to produce zero-trans margarine with minimized post-hardening crystallization (Miskandar et al, 2018).…”