Physical and Chemical Parameters of Emulsifiers and Their Effect on the Process of Food Emulsion Formation

Introduction. Modern food science needs new research of food emulsifiers, their composition, properties and effect on the structural characteristics of emulsions. It looks for modern technological solutions on how to select proper emulsifiers and their mixes to produce emulsions with different mass fractions of fat. The research objective was to study the effect of physical and chemical indicators of surfactants on the properties of food emulsions, as well as to develop practical recommendations for the selection of surfactants for various types of products. Study objects and methods. The research featured model dairy fat emulsions and laboratory-made vegetable oil, as well as hard and soft mono- and diglycerides of fatty acids and lecithins. The emulsifiers were used to determine the melting point, fatty acid composition, iodine number, and solid triglyceride content at various temperatures. The melting point of emulsifiers was determined by fixing the melting temperature in a capillary oven. To identify the fatty acid composition, the methyl esters of fatty acids were subjected to the chromatogram method. After that, the separated components and their quantity were determined by the area of the peaks. The content of solid triglycerides in the emulsifiers was determined by the method of nuclear magnetic resonance. The hydrophilic-lipophilic balance was obtained from the manufacturer's specifications. Results and discussion. The solid mono- and diglycerides appeared to have a high content of stearic and palmitic acids. Oleic acid predominated in soft monoglycerides; unsaturated fatty acids (linolenic and oleic) also predominated in the monoglycerides/lecithin complex emulsifier. Solid monoglycerides had a high content of solid triglycerides at 35°C (82.93%), which correlated with the high melting point (80°C) and the lowest iodine number (3 mg I2/100 g) of all the samples. The optimal ratio of vegetable oil and the emulsifier was defined empirically. The emulsifiers were dissolved in refined deodorized vegetable oil at 5–7°C above the melting point of the emulsifier. The resulting ratios were between 6:1 and 10:1. The samples of creamy vegetable spreads were obtained using the studied emulsifiers and their compositions in different doses and ratios. The crystallization temperature and phase transition time were determined when studying the process of emulsion overcooling. The article introduces a list of technological and physicochemical indicators of emulsifiers: the fatty acid composition, the degree of saturation, the melting point, and the content of solid triglycerides. By finding out the physicochemical parameters of emulsifiers, producers can vary the ratio of the components of emulsifying compositions to achieve the desired properties of food emulsions. The hydrophilic-lipophilic balance also proved to be an important index since the proportion of hydrophilic and hydrophobic groups in surfactants affects the type of emulsions and makes it possible to adjust the fat content of the finished product. Conclusion. The research results can expand the theoretical foundations of food emulsions. The article contains scientifically grounded recommendations on how to select optimal surfactants. The research opens up prospects for further studies of emulsifiers and their effect on the quality of finished products.

Physicochemical Upgrading of a Biodetergent for Application in the Industrial Energy Sector

In the industries across the petroleum chain and those involved in energy generation, the use of petroderivatives as fuel oils is common. To clean parts, equipment and environments contaminated by hydrocarbons, they use expensive, toxic products, bringing risks to the environment as well as to workers’ health. Thus, the aim of this study was to check the stability of a biodetergent prepared using atoxic substances for large-scale production and industrial energy sector application. The relationship between volume (4 to 10 L) and stirring time (5 to 10 min) of the formulation at 3200 rpm and 80 °C was evaluated. The hydrophilic lipophilic balance (HLB), long-term stability (365 days), toxicity and efficiency of low-sulfur, viscous fuel oil removal from metal pieces and floors were investigated. The interaction among operating conditions was shown to influence the features of the product, which achieved approximately 100% stability after a stirring time of 7 min. The emulsion HBL index varied between 4.3 and 11.0. The biodetergent maintained its physicochemical properties during its 365 days of storage and showed high efficiency, removing 100% of the OCB1 impregnated on the metallic surfaces and floors tested. The formulation showed reliability in scale up when submitted to the study of physicochemical factors in the productive process, and safe application, by reducing risks for workers’ health and environment.

Antimicrobial Formulation of Chrysopogon zizanioides Essential Oil in an Emulsified Lotion for Acne

Acne is a skin condition arising from excess sebum production and microbial overgrowth within the pilosebaceous unit. Several commercial essential oils have shown promising activity against acne-related pathogens. Due to their volatility and thermal instability, the formulation of essential oils into commercial products remains a pharmaceutical challenge. Thus, this study aimed to develop a viable anti-acne topical treatment as an oil-in-water emulsified lotion to overcome these challenges. Chrysopogon zizanioides (vetiver) displayed noteworthy antimicrobial activity with a mean minimum inhibitory concentration of 0.14 mg/mL against Cutibacterium acnes, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. Emulsified lotions containing C. zizanioides were developed through the hydrophilic-lipophilic balance approach. At tested hydrophilic-lipophilic balance values of 8, 9, and 10, C. zizanioides emulsified lotions displayed maximum stability at hydrophilic-lipophilic balance 9 with a minimum change in mean droplet size and polydispersity index of 20.61 and 33.33%, respectively, over 84 days. The C. zizanioides emulsified lotion at optimum hydrophilic-lipophilic balance 9 completely inhibited the growth of C. acnes and killed S. aureus, S. epidermidis, and S. pyogenes within 24 h. Additionally, the lotion retained antimicrobial activity against these test micro-organisms over the 84-day stability test period. Thus, the C. zizanioides emulsified lotion demonstrated physical stability and antimicrobial efficiency, making it an ideal natural product anti-acne treatment.

Artificial Phylloplanes Resembling Physicochemical Characteristics of Selected Fresh Produce and Their Use in Bacteria Attachment/Removal Studies

The recurrence of food-borne illness outbreaks caused by consumption of fresh produce highlights the importance of developing a good understanding of the bacteria-leaf-surfaces interactions. In this study, we proposed and developed a new method to fabricate artificial phylloplanes that mimic the topographical and epicuticular characteristics of fresh produce, to be used as a platform for the development of food safety interventions for fresh produce. Romaine lettuce and spinach were selected to create phylloplane replicas using a double-cast procedure. The surface hydrophobicity of the artificial phylloplanes made from polydimethylsiloxane (PDMS) was modified by adding a non-ionic surfactant with different hydrophilic-lipophilic balance (HLB) values to match the hydrophobicity of produce leaves. Key epicuticular wax compounds identified from the natural spinach and lettuce leaves were coated on the leaf replica to mimic the chemical composition of natural leaf surfaces. These surrogate surfaces were used to study the attachment Escherichia coli O157:H7 and Listeria innocua. In addition, these surfaces are reusable, and have surface hydrophobicity, surface roughness values and epicuticular wax compositions similar to fresh produce. The artificial phylloplanes of fresh produce can be used as a platform for studying the interactions between human pathogens with produce surfaces and for developing new sanitation strategies.

Biocidal Activity of a Nanoemulsion Containing Essential Oil from Protium heptaphyllum Resin against Aedes aegypti (Diptera: Culicidae)

This work aimed to prepare a nanoemulsion containing the essential oil of the Protium heptaphyllum resin and evaluate its biocidal activities against the different stages of development of the Aedes aegypti mosquito. Ovicide, pupicide, adulticide and repellency assays were performed. The main constituents were p-cymene (27.70%) and α-pinene (22.31%). The developed nanoemulsion showed kinetic stability and monomodal distribution at a hydrophilic–lipophilic balance of 14 with a droplet size of 115.56 ± 1.68 nn and a zeta potential of −29.63 ± 3.46 mV. The nanoemulsion showed insecticidal action with LC50 0.404 µg.mL−1 for the ovicidal effect. In the pupicidal test, at the concentration of 160 µg.mL−1, 100% mortality was reached after 24 h. For adulticidal activity, a diagnostic concentration of 200 µg.mL−1 (120 min) was determined. In the repellency test, a concentration of 200 µg.mL−1 during the 180 min of the test showed a protection index of 77.67%. In conclusion, the nanobiotechnological product derived from the essential oil of P.heptaphyllumresin can be considered as a promising colloid that can be used to control infectious disease vectors through a wide range of possible modes of applications, probably as this bioactive delivery system may allow the optimal effect of the P. heptaphyllum terpenes in aqueous media and may also induce satisfactory delivery to air interfaces.

Simultaneous Determination of Albendazole and Its Three Metabolites in Pig and Poultry Muscle by Ultrahigh-Performance Liquid Chromatography-Fluorescence Detection

A fast, simple and efficient ultrahigh-performance liquid chromatography-fluorescence detection (UPLC-FLD) method for the determination of residues of albendazole (ABZ) and its three metabolites, albendazole sulfone (ABZ-SO2), albendazole sulfoxide (ABZ-SO), and albendazole-2-aminosulfone (ABZ-2NH2-SO2), in pig and poultry muscle (chicken, duck and goose) was established. The samples were extracted with ethyl acetate, and the extracts were further subjected to cleanup by utilizing a series of liquid–liquid extraction (LLE) steps. Then, extracts were purified by OASIS® PRiME hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE) cartridges (60 mg/3 mL). The target compounds were separated on an ACQUITY UPLC® BEH C18 (2.1 mm × 100 mm, 1.7 μm) chromatographic column, using a mobile phase composed of 31% acetonitrile and 69% aqueous solution (containing 0.2% formic acid and 0.05% triethylamine). The limits of detection (LODs) and limits of quantification (LOQs) of the four target compounds in pig and poultry muscle were 0.2–3.8 µg/kg and 1.0–10.9 µg/kg, respectively. The recoveries were all above 80.37% when the muscle samples were spiked with the four target compounds at the LOQ, 0.5 maximum residue limit (MRL), 1.0 MRL, and 2.0 MRL levels. The intraday relative standard deviations (RSDs) were less than 5.11%, and the interday RSDs were less than 6.29%.

Entrapment of Phenylalanine Ammonia-Lyase in Nanofibrous Polylactic Acid Matrices by Emulsion Electrospinning

Immobilization of the recombinant, plant-derived Petroselinum crispum phenylalanine ammonia lyase (PcPAL) in electrospun matrices have the potential to create promising, easy-to-use biocatalysts. Polylactic acid (PLA) a biologically inert, commercial biopolymer, was chosen as the material of the carrier system. PLA could be electrospun properly only from water-immiscible organic solvents, which limits its application as a carrier of sensitive biological objects. The emulsion electrospinning is a proper solution to overcome this issue using non-ionic emulsifiers with different hydrophilic-lipophilic balance (HLB) values. The stabilized emulsion could protect the sensitive PcPAL dissolved in the aqueous buffer phase and improve fiber formation, plus help to keep the biocatalytic activity of enzymes. In this study, the first approach is described to produce PLA nanofibers containing PcPAL enzymes by emulsion electrospinning and to use the resulted biocatalyst in the ammonia elimination reaction from l-phenylalanine.

Effective and rugged analysis of glyphosate, glufosinate, and metabolites in Tenebrio molitor larva (mealworms) using liquid chromatography tandem mass spectrometry

Tenebrio molitor larva (mealworms) has recently attracted attention as a protein source for food and feed. The larva is generally fed with wheat bran, which can be possibly contaminated with glyphosate. To establish food safe standards, a rugged and effective analytical method for glyphosate, aminomethylphosphonic acid, glufosinate, and their metabolites including 3-methylphosphinico-propionic acid, and N-acetyl glufosinate, in mealworms was optimized using liquid chromatography tandem mass spectrometry. An anionic polar pesticide column was used due to its high suitability for glyphosate. Acidified water and acetonitrile were used to extract the target compounds without contribution from various fatty and pigment interferences derived from brownish insects. Seven different clean-up procedures ((1) 50 mg C18 (2) 20 mg C18/Z-sep (3) PRiME hydrophilic-lipophilic balance (HLB) cartridge (4) 75 mg Z-sep, (5) 75 mg Z-sep+, (6) EMR-lipid cartridge, and (7) 50 mg ENVI-Carb) were compared. Due to its simplicity and cost-effectiveness, PRiME HLB was selected for clean-up. The recoveries of the target compounds were ranged from 86 to 96% with < 20% relative standard deviations. Therefore, this simple and effective method can be applied for the two pesticides and their metabolites in other edible insects or high-fat matrices.