Sodium Caseinate Emulsions Research Articles

Influence mechanism of chayote (Sechium edule) pectin on the stability of sodium caseinate emulsion

Chayote (Sechium edule), a vegetable with high economic value worldwide, is rich in pectin. At present, there are few reports on the application of chayote pectin (CP) in food emulsion. In this study, the effect of CP concentrations and system conditions (e.g, pH and NaCl concentrations) on the properties of sodium caseinate (CAS) emulsion were investigated, with apple pectin as the control. The addition of pectin increased the negative charge on the emulsion. For CAS-CP emulsion (mixing ratio was 2:1), the zeta-potential changed from positive (8.41 ± 1.15 mV) to negative (−6.06 ± 0.39 mV) at pH 4. In the neutral environment, when the CAS: CP mixing ratio was 2:1 and 1:1, the emulsion creaming indexes were (84.39 ± 1.52) % and (66.04 ± 1.53) %, respectively. In an acidic environment, due to the electrostatic repulsion, viscosity, and steric hindrance, the emulsion was stable when the mixing ratio of CAS: CP was 1:1. In addition, NaCl caused the phenomenon of creaming. The effects of apple pectin on the properties of CAS emulsion were similar to those of CP. Overall, this study can provide a novel idea for applying CP in emulsion.

Interfacial effects of gallate alkyl esters on physical and oxidative stability of high fat fish oil-in-water emulsions stabilized with sodium caseinate and OSA-modified starch.

Effects of sodium caseinate (SC) and its combination with OSA-modified starch (SC-OS; 1:1) alone and with n-alkyl gallates (C0-C18) on the physical and oxidative stability of high-fat fish oil-in-water emulsion were evaluated. SC emulsion contained the smallest droplets and highest viscosity due to the fast adsorption at droplet surfaces. Both emulsions had non-Newtonian and shear-thinning behavior. A lower accumulation of lipid hydroperoxides and volatile compounds was found in SC emulsion due to its better Fe2+ chelating activity. The incorporated short-chain gallates (G1>G0∼G3) in SC emulsion had a strong synergistic effect against lipid oxidation compared to that of SC-OS emulsion. The better antioxidant efficiency of G1 can be related to its higher partition at the oil-water interface, while G0 and G3 had a higher partition into the aqueous phase. In contrast, G8, G12, and G16 added emulsions indicated higher lipid oxidation due to their internalization inside the oil droplets.

Competitive adsorption of sodium caseinate or ovalbumin by Tween 80 impact the mechanical and microstructural properties of emulsified surimi gel systems

SummaryThis study first explored the competitive displacement of sodium caseinate (SC) and ovalbumin (OVA) by Tween 80 (TW) on the mechanical and microstructural properties of emulsified surimi systems. The interfacial tension of TW (8.02 ± 0.58 mN m−1) was significantly lower than that of SC (10.45 ± 0.62 mN m−1) and OVA (11.78 ± 0.69 mN m−1), and TW's addition significantly decreased the interfacial protein concentration in SC emulsion from 2.04 ± 0.18 to 1.31 ± 0.28 mg m−2 and OVA emulsion from 3.53 ± 0.04 to 2.51 ± 0.12 mg m−2 respectively (P < 0.05). The SC‐ and OVA‐emulsified gels exhibited higher hardness, adhesiveness, chewiness, gel strength, equilibrium stress, recovery rate and quality factor (Q) than TW/SC‐ or TW/OVA‐emulsified gels. Emulsion droplets are embedded in the gel matrix and evenly distributed in SC‐, OVA‐ and SC/OVA‐emulsified gel. However, in TW‐, TW/SC‐ and TW/OVA‐emulsified gel, local phase separation occurs between aggregated protein particles and oil droplets, resulting in highly heterogeneous structures. This study provides a valuable reference for utilising compound emulsifiers in the surimi industry.

Effects of high acyl gellan gum on the rheological properties, stability, and salt ion stress of sodium caseinate emulsion

Sodium caseinate (SC) is widely used as a biological macromolecular emulsifier in oil-in-water (O/W) emulsions. However, the SC-stabilized emulsions were unstable. High-acyl gellan gum (HA) is an anionic macromolecular polysaccharide that improves emulsion stability. This study aimed to investigate the effects of HA addition on the stability and rheological properties of SC-stabilized emulsions. Study results revealed that HA concentrations >0.1 % could increase Turbiscan stability, reduce the volume average particle size, and increase the zeta-potential absolute value of the SC-stabilized emulsions. In addition, HA increased the triple-phase contact angle of SC, transformed SC-stabilized emulsions into non-Newtonian fluids, and effectively inhibited the movement of emulsion droplets. The effect of 0.125 % HA concentration was the most effective, allowing SC-stabilized emulsions to maintain good kinetic stability over a 30-d period. NaCl destabilized SC-stabilized emulsions but had no significant effect on HA-SC emulsions. In summary, HA concentration had a significant effect on the stability of SC-stabilized emulsions. HA altered the rheological properties and reduced creaming and coalescence by forming a three-dimensional network structure, increasing the electrostatic repulsion of the emulsion and the adsorption capacity of SC at the oil-water interface, and thereby improving the stability of SC-stabilized emulsions during storage and in the presence of NaCl.

Synergistic effects of psyllium husk powder and different levels of methylcellulose on the storage stability of sodium caseinate emulsion.

The study investigated the effects of compound fibers composed of psyllium husk powder (PHP, 0.3%) and methylcellulose (MC, 0, 0.3, 0.6, 0.9, and 1.2%) on the storage stability, rheology, and microstructure of sodium caseinate emulsions. Results showed that the emulsion stability was enhanced with the increased concentrations of MC, especially at the concentration of 1.2%. The oil droplet size in the emulsions was decreased as the concentrations of compound fibers increased, which was further confirmed by the optical microscope analysis. The rheological measurements and cryo-scanning electron microscopy results indicated that compound fibers improved the viscosity of the emulsions, and formed a strong three-dimensional network structure. The results of confocal laser scanning microscope and surface protein concentration measurements showed that compound fibers were evenly distributed into the oil droplet surface. The above results demonstrate that compound fibers are an effective thickener and emulsifier in enhancing the stability properties of oil-in-water (O/W) emulsions stabilized by sodium caseinate.

Properties of sodium caseinate as affected by the β-casein phenotypes

The aim of the study was to investigate the properties of sodium caseinate dispersions and oil-in-water emulsions obtained from cows’ milk of either A1/A1, A1/A2, or A2/A2 β-casein phenotype. Protein structural characterisation was examined using Fourier Transform Infrared and Nuclear Magnetic Resonance spectroscopies, with physicochemical and interfacial properties assessed by analysing adsorbed protein content, hydrophobicity, solubility, and emulsion stability of the samples. Results showed variations in the secondary structure of all samples dependent of the presence of A1 or A2 β-caseins. The main differences included greater amounts of α-helix and β-sheet in A1/A1 and A1/A2 sodium caseinate dispersions that influenced their lower solubility, while random coils/polyproline II helixes were found only in A2/A2 sodium caseinate dispersion. In contrast, upon adsorption on the interface of A2/A2 sodium caseinate emulsion, the protein adopted ordered conformational motifs. This conformational shift supposedly arose from structural differences between the two β-casein proteoforms, which most likely enhanced the emulsion properties of A2/A2 sodium caseinate compared to either A1/A1 or A1/A2 sodium caseinates. The A2 β-casein in both, A1/A2 and A2/A2 sodium caseinates, appears to be able to more rapidly reach the oil droplet surface and was more efficient as emulsifying agent. The current results demonstrated that the conformational rearrangement of proteins upon adsorption to emulsion interfaces was dependent not only on hydrophobicity and on solubility, but also on the conformational flexibility of A1/A1, A1/A2, and A2/A2 β-casein phenotypes. These findings can assist in predicting the behaviour of sodium caseinates during relevant industrial processing.

Fabrication and characterization of solvent evaporation-assisted sodium caseinate emulsion films

As plastic pollution increases, the development of degradable film has attracted much attention. Sodium caseinate was suitable to be a degradable film material for its mechanical performance and appearance. Maize oil was added to improve the properties of film material by microfluidization and solvent evaporation. Microfluidization could improve the droplet distribution of maize oil in the film building dispersions and the performance of film material. Solvent evaporation could further control the droplet distribution and the characteristics of film materials. The introduction of ethyl acetate could refine the droplet of maize oil distributing in the film building dispersions. The mechanical characteristics, water blocking properties and microscopic structure of solvent evaporation-assisted sodium caseinate emulsion films were improved.

Co-encapsulation of α-tocopherol and resveratrol in oil-in-water emulsion stabilized by sodium caseinate: Impact of polysaccharide on the stability and bioaccessibility

Naturally self-assembling property of sodium caseinate (SC) provides the possibility of loading bioactive compounds to the oil-water interface of oil-in-water (O/W) emulsions. In this study, α-tocopherol (TOC) and resveratrol (RES) were encapsulated in the inner oil phase and the oil-water interface of SC-stabilized emulsions, respectively. Addition of polysaccharides increased the size and absolute value of ζ-potential of SC emulsions and surface coverage of oil droplets, improving the encapsulation of RES at the oil-water interface and storage stability of both TOC and RES. The effects were more pronounced in the presence of pectin (PEC) than gum Arabic (GA). Moreover, the digestive stability of TOC in SC emulsions was only improved by 0.5% and 1.0% PEC. Addition of 0.1–1.0% GA and 0.1% PEC promoted the bioaccessibility of TOC (~40%) and RES (~90%). These results should be useful for the co-encapsulation of bioactive components with different solubility based on protein-stabilized single emulsions.

Characterization of physicochemical properties of casein mixture preparation extracted from organic milk for use as an emulsifier in organic processed foods.

Sodium caseinate (SC) is not considered suitable for use as an emulsifier in organic processed food in the food industry because of the use of prohibited synthetic chemical substances during its production. Casein mixture preparation (CMP), one of the permissible substances specified in the regulations, was isolated from organic milk using citric acid and dibasic potassium phosphate for organic processed foods. To compare CMP and SC, model emulsions stabilized with each substance were prepared at various concentrations and their physicochemical properties were analyzed. The emulsions' stability was determined using Turbiscan under various environmental stresses. The zeta potential of SC and CPM showed a high surface charge (≤ 30 mV) at all protein concentrations. Because the concentration of the protein preparation increased to 0.75% (w/v), the particle size of the CMP emulsion decreased with the surface load increased as much as that of SC. The CMP and SC emulsions were stable at neutral pH and room temperature. However, at acidic pH and high temperature, both emulsions were destabilized by creaming and flocculation and increased the creaming migration rates. Overall, our data suggest the use of CMP as an emulsifier substitute for SC in organic processed foods. © 2018 Society of Chemical Industry.

Flocculation of oil-in-water emulsions stabilised by milk protein ingredients under gastric conditions: Impact on in vitro intestinal lipid digestion

The effect of the gastric behaviour of protein-stabilised oil-in-water emulsions on intestinal lipid digestion was investigated using an in vitro dynamic gastric digestion model ‒ the human gastric simulator (HGS) and an intestinal model. Emulsions were prepared using milk protein concentrate (MPC), calcium-depleted MPC or sodium caseinate. In the MPC-stabilised emulsion, flocculation, induced by the milk-clotting enzyme pepsin, occurred after 10 min of digestion (at pH > 6) in the HGS. Closely knitted flocs of large size, which remained in the HGS throughout the gastric digestion, were formed. However, in emulsions stabilised by calcium-depleted MPC or sodium caseinate, flocculation occurred after approximately 40 min of digestion because of the low pH (∼pH 5); the flocs were relatively small and disintegrated after further digestion. The particle sizes of the gastric digesta mixtures obtained at each digestion time were in the order: MPC emulsion > calcium-depleted MPC emulsion > sodium caseinate emulsion. In contrast, the oil contents of the mixtures were in the order: MPC emulsion < calcium-depleted MPC emulsion < sodium caseinate emulsion, suggesting that the MPC emulsion had a slower release of oil droplets into the intestine than the calcium-depleted MPC and sodium caseinate emulsions. In the intestinal phase, the extent of lipid digestion followed the order: MPC emulsion < calcium-depleted MPC emulsion ≤ sodium caseinate emulsion. The results suggested that the structures and the size of the flocs induced by interactions between milk proteins and pepsin or acid during the gastric digestion of emulsions influence intestinal lipid digestion.

The Influence of Emulsion Droplet Interactions on the Structural, Material and Functional Properties of a Model Mozzarella Cheese

We present findings on the influence of interfacial layer composition on the colloidal interactions and associated structural and material properties of oil-in-protein gel emulsions, as applied to a model Mozzarella cheese analogue. Model cheese samples were produced through thermal mixing of pre-prepared oil-in-water emulsions with a renneted casein gel. Sodium caseinate and Tween 20 were used as the emulsifiers. Microstructural analysis showed sodium caseinate stabilised droplets to be homogeneously dispersed within the cheese structure, whilst droplets stabilised by Tween 20 were phase concentrated into localised fat domains within the continuous protein network. Particle size measurements determined that, on chilled storage, the droplets in these localised regions underwent extensive partial coalescence, whilst the homogenously distributed caseinate droplets showed little change in droplet size. Small deformation rheology (4 to 80 °C) determined the sodium caseinate emulsion as providing a reinforcing effect on the protein network across the entire temperature range, while the Tween 20 emulsion was observed to mechanically strengthen the cheese structure at only at temperatures for which the fat phase was solid whilst serving to weaken the structure on transitioning to a molten state. Differences in droplet structure and stability were determined as influencing cheese melt and flow characteristics. During melting, no oiling-off observed for cheese samples comprising sodium caseinate stabilised droplets, compared to Tween 20 stabilised emulsions where extensive oiling-off was observed. Findings corroborate the hypothesis that caseinate coated droplets behave as active fillers within the protein network, whilst the Tween 20 stabilised emulsion are non-interactive.

Tea polyphenols association to caseinate-stabilized oil–water interfaces

Tea Catechins associate with proline rich proteins such as caseins. In this work, the interactions between epigallocatechin-gallate (EGCG), one of the main tea catechins, and caseins at an oil water interface were studied. The association of EGCG with sodium caseinate was quantified by measuring the amount of EGCG adsorbed on the emulsion droplets. In addition, the viscoelastic properties of the protein and EGCG–protein layers formed at the interface were studied using drop tensiometry. Different concentrations of EGCG were added to a model emulsion to obtain final concentrations of 10% soybean oil, 0.5% sodium caseinate and 0–9 mg/mL EGCG. At concentrations < 2 mg/mL EGCG, more than 90% was adsorbed at the interface. At higher concentrations, below 5 mg/mL, about 70% of EGCG was adsorbed. The surface load reached about 1 mg/m2 at 9 mg/mL of EGCG. The dissociation constant for the complex formed, was estimated using schatchard plot, and was 3.7 × 10−5 M for less than 20 mol bound EGCG/protein. The interactions of EGCG with sodium caseinate did not affect the interfacial tension but increased the dilational modulus of the EGCG-protein layer at the interface. This study demonstrated that sodium caseinate emulsions could be employed as carriers for EGCG, and that the complexes formed at the interface are affecting the physico-chemical properties of the emulsions. The results are of significance in the development of dairy based beverages containing tea polyphenols.

In vivo postprandial bioavailability of interesterified-lipids in sodium-caseinate or chitosan based O/W emulsions

Recent studies have shown that it should be possible to control lipid bioavailability through food structural approaches. Nevertheless, the gastrointestinal-tract physiological conditions must also be considered. To get a better understanding of this phenomenon, we evaluated the effect of emulsification, as well as the use of sodium caseinate or chitosan, on the postprandial bioavailability of interesterified-lipids in O/W emulsions after oral gastric feeding Sprague–Dawley rats. We verified that emulsification may increase lipid absorption, as determined after feeding sodium-caseinate emulsions. However, this result could not be generalised. Interesterified-lipids that were emulsified with chitosan were equally absorbed as those contained in non-emulsified interesterified-lipids/distilled-water blends.

The physicochemical stability and in vitro bioaccessibility of beta-carotene in oil-in-water sodium caseinate emulsions

Beta-carotene (BC), the most important dietary source of provitamin A, is necessary for optimum human health. BC is insoluble or only slightly soluble in most liquids but its bioavailability improves when ingested with fat. Therefore lipid emulsions are ideal matrices for BC delivery. BC (0.1%) in corn oil, the dispersed phase (5 or 10%), was homogenized with 2% sodium caseinate solution in a microfluidizer. Homogenization at different pressures produced droplet diameters (Dz = 368–124 nm) that were linear and inversely related to homogenization pressures in the pressure range 10–100 MPa. Nanoemulsions (r < 200 nm) were prepared at 100 MPa. The sodium caseinate emulsions were generally very stable to coalescence or flocculation over 30 days and the slow rate of volume increase was found to be related to the square of the initial droplet radius following Stokes velocity of settling equation. BC stability towards oxidation was lower as droplet diameter decreased. The extent of lipolysis in an in vitro system was higher and linearly related to the inverse of droplet diameter. Bioaccessibility, as defined by the amount of BC recovered in the aqueous phase after ultracentrifugation, was linearly related to smaller emulsion droplet diameter. These results show that sodium caseinate, a food grade emulsifier, can be used to prepare stable emulsions of food oils carrying beta-carotene. Since food oils facilitate the uptake of beta-carotene this may be a preferred system to deliver beta-carotene.

Kinetic study of aggregation of milk protein and/or surfactant-stabilized oil-in-water emulsions by Sedimentation Field-Flow Fractionation

Milk proteins are able to facilitate the formation and stabilization of oil droplets in food emulsions. This study employed Sedimentation Field-Flow Fractionation (SdFFF) to monitor changes in particle size distribution of freshly prepared emulsions with varying weight contributions of sodium caseinate (SC) and whey protein concentrate (WPC). The effect of the addition of Tween 80 (T) on the initial droplet size was also investigated. The results indicated that emulsifying ability follows the order Tween 80>WPC>SC, with corresponding weight average droplet diameter of 0.319, 0.487 and 0.531μm respectively, when each of the above emulsifiers was used solely. The stability of sodium caseinate emulsions was studied at 30.5 and 80.0°C by measuring the particle size distribution for a period of 70h. Emulsions withstood the temperatures and exhibited an initial increase in particle size distribution caused by heat-induced droplet aggregation, followed by a decrease to approximately the initial droplet size. The rate of droplet aggregation depends on the severity of thermal processing, as revealed by the kinetics of particle aggregation during aging at different temperatures. Comparison of the experimental rate constants found from SdFFF, with those determined theoretically gives invaluable information about the oil droplet stability and the aggregation mechanism. Based on the proposed mechanistic scheme various physicochemical quantities, which are very important in explaining the stability of oil-in-water emulsions, were determined. Finally, the advantages of SdFFF in studying the aggregation of the oil-in-water droplets, in comparison with other methods used for the same purpose, are discussed.

Influence of pH value and locust bean gum concentration on the stability of sodium caseinate-stabilized emulsions

Sodium caseinate emulsions of 20% sunflower oil in water were prepared at various pH and Locust Bean Gum concentrations (LBG). The presence of LBG was examined to assess the stabilizing properties in relation to flocculation, creaming and coalescence, in the initial emulsions as well as freeze-thawed and freeze-dried/reconstituted samples. We found the initial emulsions to be stable at pH 6.0 and 6.5, both in the absence or presence of LBG, against creaming. However we found evidence for the aggregates of emulsion droplets in the presence of LBG. Strong shear thinning behavior, even at low shear rates, and micrographs indicated that the presence of LBG may promote flocculation by mediating depletion forces between the oil droplets. However, the absence or low concentrations of LBG resulted in creaming followed by the emulsion break-up for the freeze-dried/reconstituted emulsions, particularly at lower pH. We have also detected a proliferation in the number of very small sub-micron particles in the particle size distribution, for samples containing higher concentrations of LBG, following the freeze-thaw cycle. We believe these to be LBG aggregates nucleating during the freezing phase of the process as the polysaccharide solubility declines with temperature.

Composition and emulsifying properties of a milk fat globule membrane enriched material

The milk fat globule membrane (MFGM) contains proteins and phospholipids with potential technological functionalities. The emulsifying properties of MFGM fragments concentrated from reconstituted buttermilk using microfiltration (MF-BM) were compared with those of buttermilk powder (BMP), skim milk powder (SMP) and sodium caseinate (SC). Oil-in-water emulsions stabilised with MFGM fragments, at identical total protein/soybean oil ratios, were prepared using a two-step homogeniser at pressures of 0/2, 3/2, 9/2, 15/2 and 21/2 MPa. Above 15/2 MPa, droplet aggregation was observed with BMP or SMP emulsions, whereas no aggregation was observed with MF-BM emulsions. MF-BM emulsions prepared at 9/2 MPa showed a monomodal particle size distribution with an average droplet size of about 3.5 μm, significantly smaller compared with BMP and SMP emulsions. Emulsion viscosity depended on emulsifying materials and homogenisation pressures. Sodium caseinate emulsions showed poor stability. These results indicate the potential of MF-BM as emulsifiers for the development of new products.

Improvement of emulsifying properties of milk proteins with κ or λ carrageenan: effect of pH and ionic strength

SummaryThe objective of this work was to determine the effect of λ‐carrageenan or κ‐carrageenan on the emulsion capacity, emulsion work and emulsion stability of milk proteins concentrate (MP) or sodium caseinate (SC) emulsions at different levels of pH and ionic strength. Incorporation of carrageenans to proteins emulsions resulted in an improvement of emulsifying properties at pH 6.0 and low ionic strength (0.2 m NaCl). Although emulsion capacity was high in MP than for SC, irrespectively of carrageenan employed, addition of λ‐carrageenan increased twofold emulsion work values (15 327 Ω s−1 for MP and 11 455 Ω s−1 for SC; around 6000 Ω s−1 in the other treatments). Emulsion stability was high with λ‐carrageenan (9.8 s) than MP‐κ‐carrageenan or MP (7.45 and 7.40 s, respectively). Carrageenan improving of emulsion properties was because of the complex formation with MP, characteristic of this type of food system when pH was above of isoelectric point.

Effect of processing conditions and composition on sodium caseinate emulsions stability

Many food products such as ice cream, yoghurt, and mayonnaise are some examples of emulsion-based food. The physicochemical properties of emulsions play an important role in food systems as they directly contribute to texture, sensory and nutritional properties of food. One of the main properties is stability which refers to the ability of an emulsion to resist physical changes over time. The aim of the present work was to analyze the effect of processing conditions and composition on sodium caseinate (NaCas) emulsions stability. The main destabilization mechanisms were identified and quantified. The relationship between them and the factors that influence them were also investigated. Emulsions stabilized with NaCas were prepared using an ultrasound liquid processor or a high pressure homogenizer. Stability of emulsions was followed by a Turbiscan (TMA 2000) which allows the optical characterization of any type of dispersion. The physical evolution of this process is followed without disturbing the original system and with good accuracy and reproducibility. To further describe systems, droplet size distribution was analyzed with light scattering equipment. The main mechanism of destabilization in a given formulation depended on different factors such as NaCas concentration, droplet size or processing conditions. The rate of destabilization was markedly lower with addition of sugar or a hydrocolloid to the aqueous phase. Xanthan (XG) and locust bean (LBG) gums produced an increase in viscosity of the continuous phase and structural changes in emulsions such as gelation. Sugars interacted with the protein decreasing particle size and increasing emulsion stability. The stability of caseinate emulsions was strongly affected not only by the oil-to-protein ratio but also by processing conditions and composition of aqueous phase. The structure of the protein and the interactions protein–sugar or the presence of a hydrocolloid played a key role in creaming and flocculation processes of these emulsions.

Effect of glycation on sodium caseinate-stabilized emulsions obtained by ultrasound

This work explores the potential of high-intensity ultrasound to produce fine-dispersion, long-time-stable, oil-in-water emulsions prepared with native and glycated bovine sodium caseinate (SC). Regardless the ultrasound amplitude and time assayed, the sonicated emulsions of native SC at 0.5 mg/mL had much higher emulsifying activity indexes compared with those emulsions formed by Ultra-Turrax (IKA Werke GmbH & Co., Staufen, Germany) homogenization. Nevertheless, the native SC emulsions were very unstable despite the optimization of parameters such as protein concentration, amplitude of ultrasound wave, and sonication time by using a Box-Behnken design. Early glycation of SC with either galactose, lactose, or 10 kDa dextran substantially improved both emulsifying activity and the stability, whereas at advanced stages of glycation, SC emulsions showed notably reduced emulsifying properties, likely because extensive glycation of SC promoted its polymerization mainly through covalent cross-linking, as was demonstrated by particle size measurements. The increase in particle diameter of glycoconjugates likely affected the diffusion of SC from bulk to the oil–water interface and slowed the reorientation process of the protein at the interface. These findings show that the combined effect of early-stage glycation of SC and high-intensity ultrasound as an emergent technique to form emulsions has the potential to provide improved emulsions that could be used in several food applications.