Rapid determination of emulsion stability by rheology-based thermal loop test

Structural and sensory impact of various emulsifiers in cocoa hazelnut spread formulations

In this study, the effects of emulsifiers such as lecithin, AMPs, Palsgaard® Oil-Binder and GMS on cocoa hazelnut spread rheology were compared under the same process conditions and formulation. Emulsifiers were added to the formulation separately at rates of 0.3%-0.4%-0.5%. Hardness values in cocoa hazelnut spread were examined at 15-day intervals until the 60th day. In addition, viscosity, rheological analyses, color, spreadability, stability tests, and sensory analyses were performed. In the production of cocoa hazelnut spread, lecithin and AMP have less hardness and lower viscosity, greater fluent consistency, better spreadability, and lower "work of shear" values compared with other emulsifiers. The emulsifier type/ratio difference did not affect the color value statistically. It was determined that the use of Oil-Binder and GMS significantly protected the stability compared with other emulsifiers. During the 60-day storage period, lecithin preserved its hardness properties better than other emulsifiers. When sensory properties were examined, the use of lecithin and AMP in cocoa hazelnut spread samples scored high in brightness, spreadability, mouthfeel, and taste parameters. As a result, lecithin comes to the fore in the use of different types and ratios of emulsifiers in cocoa hazelnut spread production technology.

Stability of high internal-phase emulsions prepared from phycocyanin and small-molecule sugars

BACKGROUND

The use of high internal-phase Pickering emulsions in the food industry is widespread due to their excellent stability and special rheological properties. Proteins are often used as food-grade Pickering stabilizers due to their safety and nutritious properties. Nowadays, the development and efficient utilization of novel proteins as Pickering stabilizers has become a new challenge.

RESULTS

Phycocyanin complexes with small-molecule sugars (SMS), formed as a result of non-thermal interactions, can serve as stabilizers for high internal-phase Pickering emulsions. The addition of SMS-enabled gel-like emulsions significantly reduced the amount of emulsifier used. When the SMS was sorbitol, the emulsion had excellent elastic properties and self-supporting ability and was stable during long-term storage, when subjected to centrifugation, and under different temperature conditions. The fluorescent property of phycocyanin was utilized to investigate the formation mechanism of the emulsion. Small-molecule sugars were able to form 'sugar-shell' structures on the surface of proteins to enhance the structural stability of proteins. Phycocyanin-SMS-stabilized emulsions provided superior protection for photosensitive and volatile substances. The retention rates of trans-resveratrol and n-hexane increased by 384.75% and 30.55%, respectively.

CONCLUSION

These findings will encourage the development of proteins that stabilize Pickering emulsions. They will also provide new ideas for protecting photosensitive and volatile substances. © 2023 Society of Chemical Industry.

Isolation of Protein and Fiber from Hot Pepper Seed Oil Byproduct To Enhance Rheology, Emulsion, and Oxidative Stability of Low-Fat Salad Dressing

This research aimed to explore the potential utilization of protein (P) and fiber (F) extracted from cold-pressed hot pepper seed oil byproduct (HPOB) in the enhancement of the rheological properties, emulsion stability, and oxidative stability of a low-fat salad dressing with 10% oil content. The assessment involved the examination of several aspects, including the physical qualities such as emulsion stability, rheological behavior, and particle size as well as the microstructure and oxidative stability. It is worth mentioning that all emulsions had desirable characteristics, including shear-thinning behavior characterized by a consistency index ranging from 6.82 to 22.32 Pa s, as well as viscoelasticity and recoverability. These qualities were notably improved with the addition of P and F of HBOP. During the thermal stability testing, it was observed that the low-fat dressing containing 1% P-1F exhibited minor changes in the G* value, indicating its exceptional emulsion stability. The control salad dressings in C1 samples contained 30% oil. (B): C2: samples containing 10% oil (low-fat salad dressing sample) exhibited ζ-potential values of -34.70 and -46.70 mV. The samples 1P-1F and 2P-1F exhibited the highest ζ-potential values. Furthermore, the increase in F resulted in a reduction in droplet size and elicited elevated values for the induction period (IP), with the exception of samples containing 1% protein, 3% fiber, and 10% oil (1P-3F). The salad dressings that included P-F exhibited enhanced oxidative stability, demonstrated by their longer IP (ranging from 5.11 to 7.04 h) compared to the control samples. The formulation consisting of samples contained 1% protein, 1% fiber, and 10% oil (1P-1F) and samples contained 2% protein, 1% fiber, and 10% oil (2P-1F) exhibited superior ζ-potential, emulsion stability, and recovery rate compared to other formulations. The findings of this investigation indicate that the interaction of proteins and fibers extracted from HPOB exhibits the potential to enhance the rheological characteristics, emulsion stability, and oxidative stability of low-fat salad dressing.

Caffeine-Containing Emulsion: Influence of the HLB and Mixing Proportions, the Oil's Chemical Composition, and the Existence of Caffeine on Emulsion Properties

This study employs a low-energy emulsification method to prepare caffeine-containing emulsions, denoted as Caf-EM. Three different oils, including coconut, sesame, and grape seed oils, are utilized along with the surfactants Span 80 and Tween 80. We investigate the influence of various factors, including (i) the hydrophilic-lipophilic balance (HLB) and surfactant ratio, (ii) the chemical composition of the oils, and (iii) the presence of caffeine, on the stability and size of emulsions. The results indicate that the HLB value and surfactant ratio are the most crucial factors affecting the emulsions' stability. The most stable Caf-EM formulation is achieved by combining mixed surfactants of Span 80 and Tween 80 with an optimal HLB value of 6.4 at a concentration of 15% (S15 to 6.4) across all oil types. This specific ratio also leads to significantly smaller emulsion droplet sizes than other ratios and is the only ratio that produces stable emulsions even without caffeine (denoted as EM). Notably, formulation S15-6.4 additionally causes a phase inversion from oil-in-water (O/W) to water-in-oil (W/O). Furthermore, the presence of caffeine in the water phase contributes to the formation of smaller and more stable emulsions. The particle size of Caf-EM is approximately 1.5 times smaller than that of EM. Regarding the oil's chemical composition, while there is a discernible trend in emulsion droplet size (coconut oil > grape seed oil > sesame oil), the differences within this sequence are insignificant, suggesting that the oil's chemical composition does not have a pronounced effect.

Capsaicin Rich Low-Fat Salad Dressing: Improvement of Rheological and Sensory Properties and Emulsion and Oxidative Stability

This study aimed to investigate the potential use of cold-pressed hot pepper seed oil by-product (HPOB) in a low-fat salad dressing to improve its rheological properties, emulsion, and oxidative stability. The total phenolic content (TPC), the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and CUPRIC reducing antioxidant capacity (CUPRAC) values were 317.4 mg GAE/100 g, 81.87%, and 6952.8 mg Trolox/100 g, respectively. The capsaicin, dihydrocapsaicin, and total carotenoid content were 175.8 mg/100 g, 71.01 mg/100 g, and 106.3 µg/g, respectively. All emulsions indicated shear-thinning, viscoelastic solid-like behavior, and recoverable characteristics, which were improved via enrichment with HPOB. The thermal loop test showed that the low-fat sample formulated with 3% HPOB indicated little change in the G* value, showing that it exhibited high emulsion stability. The induction period values (IP) of the salad dressing samples containing HPOB (between 6.33 h and 8.33 h) were higher than the IP values of the control samples (3.20 h and 2.58 h). The enrichment with HPOB retarded the formation of oxidative volatile compounds of hexanal, nonanal, and 1-octene-3-ol. According to the results presented in this study, HPOB could be effectively used in a low-fat salad dressing to enhance its rheological characteristics and oxidative stability.

The Potential Use of Cold-Pressed Coconut Oil By-Product as an Alternative Source in the Production of Plant-Based Drink and Plant-Based Low-Fat Ice Cream: The Rheological, Thermal, and Sensory Properties of Plant-Based Ice Cream

This study aimed to investigate the potential use of cold-pressed coconut oil by-products (COB) as a low-cost alternative source for plant-based drink and ice cream production. Firstly, a plant-based drink was produced from cold-pressed coconut oil by-products (COB drink) and compared with a commercial coconut drink. The fat, protein, and zeta potential values of coconut drink obtained from COB were higher than those of the commercial samples. In addition, the particle size value of the drink obtained from COB was found to be lower than that of the commercial drink. In the second stage, full-fat and low-fat plant-based ice cream samples using COB drink were produced and compared to control ice cream samples (produced by the commercial coconut drink) in terms of rheological, sensorial, and thermal properties. Rheological analysis showed that all plant-based ice cream samples indicated pseudoplastic, solid-like, and recoverable characteristics. Low-fat commercial control ice cream samples (C1) indicated the lowest K value (9.05 Pasⁿ), whereas the low-fat plant-based ice cream sample produced by the COB drink (COB-3) exhibited the highest K value (17.69 Pasⁿ). ΔH_f values of the plant-based ice cream samples varied from 144.70 J/g to 172.70 J/g. The low-fat COB ice cream stabilized with 3% COB and full-fat COB ice cream samples showed lower ΔH_f values than control ice cream samples, indicating that the COB ice cream showed desired thermal properties. The COB drink may be utilized in plant-based ice cream without altering sensory qualities, and low-fat ice cream could be manufactured in the same manner to attain full-fat ice cream quality characteristics. The results of this study demonstrated that COB can be successfully used as an inexpensive raw material source in the production of full-fat and reduced-fat vegetable-based ice cream.

Utilization of exopolysaccharide produced by Leuconostoc lactis GW-6 as an emulsifier for low-fat mayonnaise production

This study aimed to investigate the potential usage of exopolysaccharide (EPS) produced by Leuconostoc lactis GW-6 species as an emulsifier in a low-fat mayonnaise by the formation of a complex with whey protein isolate (WPI) to improve rheological properties, emulsion, and oxidative stability. For the determination of rheological properties, the flow behavior, frequency sweep, and 3-ITT rheological properties of low-fat mayonnaise samples were studied. All samples showed shear thinning, viscoelastic solid-like, and recoverable character. The K and n values for the mayonnaise samples were determined as 24.529-174.403 Pa.sⁿ and 0.166-0.304, respectively, indicating that shear-thinning characters could be improved with WPI-EPS interaction. The higher K' and K″ values of all low-fat samples prepared with EPS-WPI than the low-fat control sample explained the synergistic effect of EPS and WPI. Importantly, no effect was observed when WPI was used as alone as an emulsifier. Oxidative stability was tested by OXITEST and IP values of samples prepared by WPI and EPS were compared to control samples. In conclusion, the results of this study showed that the EPS and WPI interaction can significantly affect the rheological properties and emulsion and oxidative stability of mayonnaise samples.

Low-Fat Salad Dressing as a Potential Probiotic Food Carrier Enriched by Cold-Pressed Tomato Seed Oil By-Product: Rheological Properties, Emulsion Stability, and Oxidative Stability

This study aims to investigate the potential of the use of cold-pressed tomato seed oil by-products in a low-fat salad dressing as potential probiotic food carriers to improve the oxidative stability and emulsion stability as well as the rheological properties. The low-fat salad dressing emulsions were formulated with cold-pressed tomato seed by-product (TBP) and Lactobacillus plantarum ELB90. The optimum low-fat salad dressing formulations found were determined as 10 g/100 g oil, 0.283 g/100 g xanthan, and 2.925 g/100 g TBP. The samples prepared with the optimum formulation (SD-O) were compared with the low-fat control salad dressing sample (SD-LF) and the high-fat control salad dressing sample (SD-HF) based on the rheological properties, emulsion stability, oxidative stability, and L. plantarum ELB90 viability. The sample SD-O showed shear-thinning, viscoelastic solid, and recoverable characters. The sample SD-O showed higher IP and ΔG ⁺⁺ and lower ΔS ⁺⁺ values than those of the control samples. After 9 weeks of refrigerated storage, viable L. plantarum ELB90 cell counts of salad dressing samples were counted as 7.93 ± 0.03, 5.81 ± 0.04, and 6.02 ± 0.08 log cfu g^-1 for SD-O, SD-LF, and SD-HF, respectively. This study showed that TBP could be successfully used in a low-fat salad dressing as a potential probiotic carrier.

Some physicochemical and technological properties of cooking water of pulses as a canned industry waste: effect of ultrasound treatment during soaking

Canned products are important part of human diet and therefore, many types of canned products with high amounts are produced worldwide. During canned production, cooking water of pulses (aquafaba) is an important waste. Therefore, recycling of it is important for sustainability and economic value. In the present study, it was aimed to determine technological properties of aquafabas obtained from canned production. For this aim, chickpea, bean, kidney bean, broad bean, green pea and lentil were used in this study, and conventional soaking and ultrasound soaking was both performed. Aquafaba is a cooking water of pulses not only chickpea and also lentil, pea and bean species. Aquafaba is used for foaming, emulsifying and gelling agent as a plant based food additive. Soaking with ultrasound has shortened the soaking time of all pules as well as increased the D eff (effective diffusion constant) values. Diffusion is a basic physical mechanism for remove moisture or absorb and also give important information about physical and thermal properties of sample. “Remove moisture” term is using for drying and the other is using for hydration. The relationship between the physical properties of pulses and D eff values was observed. The protein content of aquafaba on a dry basis changed between 20 and 35% and it has been observed that there are also positive correlation with their foaming properties. Foaming capacities of aquafabas varied between 167 and 567% in conventional soaking, and between 133 and 533% in ultrasonic soaking. In both methods, chickpea aquafaba showed the lowest foaming capacity and stability, while pea had the highest foaming capacity and stability. US process generally decreased the protein content and foaming capacity (FC) of aquafabas. The foam of pea and lentil aquafabas showed higher resistant against to gravity. In contrary to the foaming properties, an increase in emulsifying properties was observed as a result of US. It has been observed that the obtained aquafabas can be used in various products in the food industry thanks to their technological features instead of animal-based ingredients.

The Potential Use of Cold-Pressed Pumpkin Seed Oil By-Products in a Low-Fat Salad Dressing: The Effect on Rheological, Microstructural, Recoverable Properties, and Emulsion and Oxidative Stability

The cold-pressed pumpkin seed oil by-product (POB) was evaluated for its application as a natural fat substitute and stabilizer in the reduced-fat salad dressings. For this aim, the samples were prepared by combining the xanthan gum (0.2–0.4 g/100 g), POB (1.0–5.0 g/100 g), egg yolk powder (3 g/100 g), and sunflower oil (10–30 g/100 g) in 17 different formulations. The optimization was carried out using response surface methodology (RSM) and full factorial central composite design (CCD). Results showed that all samples presented the shear-thinning (or pseudoplastic) flow behavior with 3.75–16.11 Pa·sⁿ and 0.18–0.30, K and n values, respectively. The flow behavior rheological data were fitted to a power-law model (R² > 0.99). The samples with high POB and low oil content showed similar K and n values compared to high oil content samples. Additionally, the dynamic rheological properties and three interval thixotropic test (3-ITT) were determined. The G′ value was larger than G″ in all frequency ranges, indicating viscoelastic solid characteristics in all samples. The optimum formulation was determined as 0.384% XG, 10% oil, and 3.04% POB. The samples prepared with the optimum formulation (POBLF-SD) were compared to low-fat (LF-SD), and high-fat (HF-SD) control salad dressing samples based on the rheological properties, emulsion stability, oxidative stability, zeta potential, and particle size. The oxidation kinetic parameters namely, IP, E_a, ΔS⁺⁺, and ΔG⁺⁺ showed that the oxidative stability of salad dressing samples could be improved by enriched by POB. The results of the present study demonstrated that POB could be considerably utilized as a natural fat substitute and stabilizer in salad dressing type emulsions.

The Effect of Cold Press Chia Seed Oil By-Products on the Rheological, Microstructural, Thermal, and Sensory Properties of Low-Fat Ice Cream

This study aimed to investigate the utilization of cold-pressed chia-seed oil by-products (CSOB) in a low-fat ice cream formulation as a fat replacer and stabilizer. In the study, ice cream emulsion mixtures were formulated by using 0.2–0.4% xanthan gum (XG), 2.5–12.5% fat, and 1–3% CSOB. Optimization was performed using the response surface methodology (RSM) and full factorial central composite design (CCD) based on the flow behavior rheological properties of the emulsions obtained from 17 different experimental points. All of the emulsion samples showed non-Newtonian shear-thinning flow behavior. The consistency coefficient (Κ) values of the emulsion samples were found to be 4.01–26.05 Pasⁿ and were significantly affected by optimization parameters (p < 0.05). The optimum formulation was determined as 0.29% XG, 2.5% CSOB, 2.5% fat. The low-fat (LF-IC) and full-fat control samples (FF-IC) were compared to samples produced with an optimum formulation (CBLF-IC) based on the steady shear, frequency sweep, and 3-ITT (three interval thixotropy test) rheological properties, thermal properties, emulsion stability, light microscope images, and sensory quality. CBLF-IC showed similar rheological behavior to FF-IC. The mix of CBLF-IC showed higher emulsion stability and lower poly-dispersity index (PDI) value and fat globule diameters than those of FF-IC and LF-IC. The thermal properties of the samples were significantly affected by the addition of CSOB in an ice cream mix. CBLF-IC exhibited a lower temperature range (ΔT), enthalpy of fusion (ΔH_f), and freezing point temperature (T_f) than those of FF-IC and LF-IC. While CBLF-IC exhibited a higher overrun value than other samples, it showed similar sensory properties to the FF-IC sample. The results of this study suggested that CSOB could be used successfully in low-fat ice cream production. This study also has the potential to gain new perspectives for the evaluation of CSOB as a fat substitute in a low-fat ice cream.