Cold‐pressed flaxseed oil by‐product as a new source of fat replacers in low‐fat salad dressing formulation: Steady, dynamic and 3‐ITT rheological properties

Recent trends in design of healthier fat replacers: Type, replacement mechanism, sensory evaluation method and consumer acceptance

In recent years, with the increasing awareness of consumers about the relationship between excessive fat intake and chronic diseases, such as obesity, heart disease, diabetes, etc., the demand for low-fat foods has increased year by year. However, a simple reduction of fat content in food will cause changes in physical and chemical properties, physiological properties, and sensory properties of food. Therefore, developing high-quality fat replacers to replace natural fats has become an emerging trend, and it is still a technical challenge to completely simulate the special function of natural fat in low-fat foods. This review aims to provide an overview of development trends of fat replacers, and the different types of fat replacers, the potential fat replacement mechanisms, sensory evaluation methods, and their consumer acceptance are discussed and compared, which may provide a theoretical guidance to produce fat replacers and develop more healthy low-fat products favored by consumers.

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.

Cold-Pressed Okra Seed Oil Byproduct as an Ingredient for Muffins to Decrease Glycemic Index, Maillard Reaction, and Oxidation

This study aimed to investigate the effects of adding cold-pressed okra seed oil byproduct (OSB) to the muffin formulation, as a partial substitute for wheat flour, on the nutritional, physicochemical, rheological, textural, and sensory properties of muffins. The carbohydrate, protein, oil, moisture, and ash contents of OSB were 44.96, 32.34, 10.21, 7.51, and, 4.98%, respectively, indicating that OSB was rich in protein and carbohydrate. All muffin samples showed a shear thinning behavior, indicating that the viscosity of all samples decreased with increasing shear rate. The frequency sweep test showed that all samples showed viscoelastic solid-like structure [G' (storage modulus)> G″ (loss modulus)]. The K' values (between 66.45 and 139.14) were higher than the K″ values (between 36.62 and 80.42) for all samples. The result was another indication of the viscoelastic solid characteristic of the samples. In our study, it was found that the fluorescence of advanced Maillard products and soluble tryptophan index decreased with increasing amount of OSB, indicating that OSB addition led to a decrease in the amount of fluorescent Maillard reaction (MR) products. The fortified muffins with more than 10% OSB had a reduced estimated glycemic index (GI) significantly in comparison with control muffin samples (p < 0.05). The induction period (IP) values of the muffin samples containing OSB (between 11:57 and 15:15 h/min) were higher than the IP value of the control sample (10:50 h/min), indicating that OSB improved the oxidative stability of the muffin samples. The addition of OSB has shown no negative effect on sensory attributes considering texture, mouth fell, odor, and taste. This study suggested that the addition of OSB in muffins could improve rheological properties and oxidative stability and decrease GI and the amount of MR products without negative impact on sensory properties.

Characteristics of reduced-fat mayonnaise prepared by oleaster as a fat replacer and natural antioxidant

Due to the disadvantages of consuming fat and synthetic preservatives, the demand to reduce them in lipid-based products like mayonnaise is increasing. In the current research, there were two goals, the first one was studying the effect of using oleaster flour in different concentrations (4%, 6%, and 8%) as a natural preservative, whereas the second one was studying the effect of oleaster as different fat replacement (FR) levels (10%, 20%, 30%, and 40%) on the physicochemical, antioxidant, and the rheological properties and stability of reduced-fat mayonnaise samples. Given results showed that with increasing the oleaster concentration, the antioxidant property increased significantly. The peroxide value after 60 days of storage for the 30% FR 8 was 2.01%, compared to the control sample without antioxidant and with TBHQ, which were 10% and 2.68%, respectively. The highest stability index (100%) was observed in the 30% FR and 40% FR samples. In terms of rheological characteristics, the 30% FR 8 oleaster showed the highest viscosity and the lowest frequency dependency. It can be concluded that oleaster has a high potential to be used in the formulation of low-fat mayonnaise as a fat replacer.

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.

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.

Highly sensitive analysis of cyanogenic glycosides in cold-pressed flaxseed oil by employing cigarette filter fiber-based SPE coupled with ultra-performance liquid chromatography-tandem mass spectrometry

In this study, a highly sensitive method for analysis of 4 cyanogenic glycosides (CNGs) in cold-pressed flaxseed oil was developed by using cigarette filter fiber-based SPE and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The cold-pressed flaxseed oil was diluted with 5% (v/v) isopropanol/n-hexane solution and loaded to a cigarette filters fiber-based SPE column for CNG enrichment and purification. Under optimized conditions, four CNGs could be detected with limits of detection ranging from 1.3 to 4.4 pg/mL. The linear range was 0.05-50 ng/ml with a linear correlation coefficient (r) > 0.9935. CNG recovery ranged from 113% to 133%, and the relative standard deviation was between 0.8% and 20.5%. Finally, the proposed method was applied to the determination of CNGs in nine cold-pressed flaxseed oils.

Extraction of Natural Gum from Cold-Pressed Chia Seed, Flaxseed, and Rocket Seed Oil By-Product and Application in Low Fat Vegan Mayonnaise

This study involves the modeling of rheological behavior of the gum solution obtained from cold-pressed chia seed (CSG), flaxseed (FSG), and rocket seed (RSG) oil by-products and the application of these gums in a low-fat vegan mayonnaise formulation as fat replacers and emulsifier. CSG, FSG, and RSG solutions showed shear-thinning flow behavior at all concentrations. The K values ranged between 0.209 and 49.028 Pa·sⁿ for CSG, FSG, and RSG solutions and significantly increased with increased gum concentration. The percentage recovery for the G′ was significantly affected by gum type and concentrations. CSG, FSG, and RSG showed a solid-like structure, and the storage modulus (G′) was higher than the loss modulus (G″) in all frequency ranges. The rheological characterization indicated that CSG, FSG, and RSG could be evaluated as thickeners and gelling agents in the food industry. In addition, the rheological properties, zeta potential, and particle size and oxidative stability (at 90 °C) of low-fat vegan mayonnaise samples prepared with CSG, FSG, and RSG were compared to samples prepared with guar gum (GG), Arabic gum (AG), and xanthan gum (XG). As a result, CSG, FSG, and RSG could be utilized for low-fat vegan mayonnaise as fat and egg replacers, stabilizers, and oxidative agents. The results of this study indicated that this study could offer a new perspective in adding value to flaxseed, chia seed, and rocket seed cold-press oil by-product.

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.

Development of Salt- and Gastric-Resistant Whey Protein Isolate Stabilized Emulsions in the Presence of Cinnamaldehyde and Application in Salad Dressing

Protein-stabilized emulsions tend to be susceptible to droplet aggregation in the presence of high ionic strengths or when exposed to acidic gastric conditions due to a reduction of the electrostatic repulsion between the protein-coated droplets. Previously, we found that incorporating cinnamaldehyde into the oil phase improved the resistance of whey protein isolate (WPI)-stabilized emulsions against aggregation induced by NaCl, KCl and CaCl2. In the current study, we aimed to establish the impact of cinnamaldehyde on the tolerance of WPI-stabilized emulsions to high salt levels during food processing and to gastric conditions. In the absence of cinnamaldehyde, the addition of high levels of monovalent ions (NaCl and KCl) to WPI-emulsions cause appreciable droplet aggregation, with the particle sizes increasing from 150 nm to 413 nm and 906 nm in the presence of NaCl and KCl, respectively. In contrast, in the presence of 30% cinnamaldehyde in the oil phase, the WPI-emulsions remained stable to aggregation and the particle size of emulsions kept within 200 nm over a wide range of salt concentrations (0-2000 mM). Divalent counter-ions promoted droplet aggregation at lower concentrations (≤20 mM) than monovalent ones, which was attributed to ion-binding and ion-bridging effects, but the salt stability of the WPI emulsions was still improved after cinnamaldehyde addition. The incorporation of cinnamaldehyde into the oil phase also improved the resistance of the WPI-coated oil droplets to aggregation in simulated gastric fluids (pH 3.1-3.3). This study provides a novel way of improving the resistance of whey-protein-stabilized emulsions to aggregation at high ionic strengths or under gastric conditions.

Biotransformation of Flaxseed Oil Cake into Bioactive Camembert-Analogue Using Lactic Acid Bacteria, Penicillium camemberti and Geotrichum candidum

This study aimed at investigating the antioxidant activity, oxidative stability, physicochemical and microbial changes of innovative vegan Camembert-analogue based on flaxseed oil cake (FOC) which was produced using lactic acid bacteria (LAB), mold Penicillium camemberti (PC) and yeast Geotrichum candidum (GC). Two variants were prepared, namely with LAB + PC and LAB + PC + GC. After fermentation for 24 h at room temperature, the samples were stored for 14 days at 12 °C and maturated for 14 days at 6 °C. Changes in microbial population, polyphenolics, flavonoids, radical scavenging capacity were evaluated. Additionally, textural changes, pH, acidity, levels of proteins, free amino acids, reducing sugars, oil content and its oxidative stability were determined. Results showed that LAB as well as fungi were capable of growing well in the FOC without any supplementation and the products were characterized by a high antioxidant potential (high polyphenolics and flavonoids contents as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide (O₂⁻) and hydroxyl (^·OH) radicals scavenging activity). This study has demonstrated that bioactivity as well as the physicochemical properties depend on the starter culture used. Due to functional and biochemical characteristics conferred to the obtained Camembert-analogues, the use of P. camemberti and G. candidum showed a potential for industrial application. There is a potential for these products to be used where non-dairy alternatives are desired.