Effects of Ultra-High-Pressure Jet Processing on Casein Structure and Curdling Properties of Skimmed Bovine Milk.

Ultra-high-pressure jet processing (UHPJ) is a new non-thermal processing technique that can be employed for the homogenization and the sterilization of dairy products. However, the effects on dairy products are unknown when using UHPJ for homogenization and sterilization. Thus, this study aimed to investigate the effects of UHPJ on the sensory and curdling properties of skimmed milk and the casein structure in skimmed milk. Skimmed bovine milk was treated with UHPJ using different pressures (100, 150, 200, 250, 300 MPa) and casein was extracted by isoelectric precipitation. Subsequently, the average particle size, Zeta potential, contents of free sulfhydryl and disulfide bonds, secondary structure, and surface micromorphology were all used as evaluation indicators to explore the effects of UHPJ on the structure of casein. The results showed that with an increase of pressure, the free sulfhydryl group content changed irregularly, while the disulfide bond content increased from 1.085 to 3.0944 µmol/g. The content of α-helix and random coil in the casein decreased, while the ß-sheet content increased at 100, 150, 200 MPa pressure. However, treatment with higher pressures of 250 and 300 MPa had the opposite effect. The average particle size of the casein micelles first decreased to 167.47 nm and then increased up to 174.63 nm; the absolute value of Zeta potential decreased from 28.33 to 23.77 mV. Scanning electron microscopy analysis revealed that the casein micelles had fractured into flat, loose, porous structures under pressure instead of into large clusters. After being ultra-high-pressure jet-processed, the sensory properties of skimmed milk and its fermented curd were analyzed concurrently. The results demonstrated that UHPJ could alter the viscosity and color of skimmed milk, shortening curdling time from 4.5 h to 2.67 h, and that the texture of the curd fermented with this skimmed milk could be improved to varying degrees by changing the structure of casein. Thus, UHPJ has a promising application in the manufacture of fermented milk due to its ability to enhance the curdling efficiency of skimmed milk and improve the texture of fermented milk.

Sandblasting Injury: A Case Report and a Review of Literature.

Sandblasting injuries are uncommon with only four reports in literature. We report a patient with a sandblasting injury of the dorsum of the hand and wrist and summarise published literature on the management of such injuries. We recommend early (<24 hours) C-arm-guided debridement of embedded foreign bodies and repeated saline washouts with a soft surgical scrub brush. Level of Evidence: Level V (Therapeutic).

Freezing kinetics and microstructure of ice cream from high-pressure-jet processing of ice cream mix.

The effect of high-pressure-jet (HPJ) processing (0-500 MPa) on low-fat (6% fat) ice cream was studied by evaluating physiochemical properties before freezing, during dynamic freezing, and after hardening. An HPJ treatment ≥400 MPa decreased the density, increased the apparent size of colloidal particles, and altered rheological behavior (increased non-Newtonian behavior and consistency coefficients) of low-fat ice cream mix before freezing. During dynamic freezing, the particle size and consistency coefficient decreased but remained higher in 400 MPa-treated samples vs. non-HPJ-treated controls at the conclusion of freezing. The resulting ice creams (400 and 500 MPa-treated) had similar hardness values (3,372 ± 25 and 3,825 ± 14 g) and increased melting rates (2.91 ± 0.13 and 2.61 ± 0.31 g/min) compared with a control sample containing polysorbate 80 (3,887 ± 2 and 1.62 ± 0.25 g/min). Visualization of ice cream samples using transmission electron microscopy provided evidence of casein micelle and fat droplet disruption by HPJ treatment ≥400 MPa. In the 400 MPa-treated samples, a unique microstructure consisting of dispersed protein congregated around coalesced fat globules likely contributed to the altered physiochemical properties of this ice cream. High-pressure-jet processing can alter the microstructure, rheological properties, and hardness of a low-fat ice cream, and further modification of the formulation and processing parameters may allow the development of products with enhanced properties.

Impact of the drilling fluid system on the effectiveness of a high pressure jetting assisted rotary drilling system.

An enhanced drill bit combining high pressure fluid jetting with a conventional rotary drilling system incorporating a tailored drilling fluid was designed to improve drilling performance in hard crystalline rock. Full scale drilling experiments (8 ½ inch bit size) were performed utilizing a specially designed sepiolite fluid and comparing its performance with water and xanthan gum as a standard geothermal drilling fluid. The novel drilling system improved the rate of penetration by over 70% compared to the conventional drill bit without jetting assistance. In addition, the sepiolite drilling fluid retained its fluid properties even after high pressure jetting.

Effect of high-pressure-jet processing on the physiochemical properties of low-fat ice cream mix.

The objective of this study was to use high-pressure-jet (HPJ) processing to produce functional properties in a low-fat (4.5% fat) ice cream mix similar to those seen when emulsifiers are used. Ice cream mix or serum (nonfat portion of the ice cream mix) were subjected to 200 or 400 MPa HPJ processing and compared with a non-HPJ-treated control. A similar non-HPJ-treated formulation but containing polysorbate 80 (0.075% wt/wt) was also used as a control. The mix samples were characterized in terms of their particle size, density, flow properties, stability, crystallization kinetics, and fat-protein interactions. The sample from the mix subjected to 400 MPa HPJ processing (HPJ-M-400) had increased consistency coefficient (5°C; 228 ± 102.7 mPa·s) and particle size (D[4,3]; 16.0 ± 2.5 µm) compared with the non-HPJ-treated control sample, with viscosity and particle size (volume-moment mean diameter, D[4,3]) values of 7.5 ± 0.4 mPa·s and 0.50 ± 0.1 µm, respectively. These differences were attributed to an increase in casein-fat interactions and casein-casein interactions caused by the 400 MPa HPJ treatment, which were observed using confocal scanning laser microscopy and inferred from an increase in protein and fat concentrations in the sediment after ultracentrifugation. Interestingly, the density of HPJ-M-400 was also lower (0.79 ± 0.17 g/mL) than that of the control (1.04 ± 0.00 g/mL) because bubbles were trapped within these complexes. The large casein-fat complexes formed in the HPJ-M-400 sample also appeared to act as steric barriers that slowed ice crystal growth during quiescent freezing. The alterations in physiochemical properties and apparent ice crystal growth induced by the 400 MPa treatment of low-fat ice cream mix have many potential applications, including clean-label confections.

Microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin: a split-face study / 中华皮肤科杂志

Objective To evaluate clinical efficacy and safety of microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin.Methods A total of 53 female patients aged 21-54 years and diagnosed with sensitive skin were enrolled from Department of Cosmetic Dermatology,Dermatology Hospital of Southern Medical University from January to June in 2018,and were divided into 3 groups by using a random number generator and a residue-based method:high-pressure jet injection group (n =23) receiving high-pressure jet injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with 0.9％ sodium chloride solution on the left side of the face (control side) once every 2 weeks,microneedle injection group (n =15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side)and microneedle-mediated injection with 0.9％ sodium chloride solution on the left side of the face (control side) once every 4 weeks,combination group (n =15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with hyaluronic acid on the left side of the face (control side) once every 4 weeks.All the patients in the above 3 groups received 4 consecutive sessions of treatment.Before the initial treatment and 2 weeks after the final treatment,erythema and skin pore scores were determined on the right and left sides of the face by using VISIA facial imaging system,lactic acid stinging test was performed,and skin sensitivity including severity of itching,dryness,erythema and scaling was evaluated.Two weeks after the final treatment,the overall improvement was evaluated with the Global Aesthetic Improvement Scale (GAIS)by clinicians and patients.Adverse reactions were recorded during and after treatment.Statistical analysis was carried out by using paired t test,Wilcoxon sign rank sum test and chi-square test.Results Two weeks after the final treatment,the improvement of skin pore score in the treatment side was superior to that in the control side in the high-pressure jet injection group (t =2.19,P =0.03),while no significant difference in the improvement of erythema score was observed between the treatment side and control side (t =1.10,P =0.27);in the microneedle injection group,the improvement of erythema and skin pore scores was greater in the treatment side than in the control side (t =2.47,3.02,both P =0.01);in the combination group,the VISIA erythema score in the treatment and control sides was 0.59 ± 0.25 and 0.85 ± 0.31 respectively,the improvement of erythema score in the treatment side was superior to that in the control side (t =5.02,P ＜ 0.01),while there was no significant difference in the improvement of skin pore score between the treatment side and control side (P ＞ 0.05).Two weeks after the final treatment,the severity of itching,dryness and scaling was significantly improved in both the treatment and control sides in the 3 groups compared with those before the initial treatment (P ＜ 0.05),while the severity of erythema was significantly improved only in the treatment side in the microneedle injection group and combination group when compared with that before the initial treatment (Z =-2.236,-2.887,respectively,both P ＜ 0.05).Moreover,both the microneedle injection group and combination group showed significantly decreased severity of erythema in the treatment side compared with that in the control side two weeks after the final treatment (Z =-2.646,-2.887,respectively,both P ＜ 0.05).Two weeks after the final treatment,the positive rate of the lactic acid stinging test significantly decreased in the treatment side compared with that before the initial treatment in the microneedle injection group (x2 =4.821,P =0.028),but showed no significant changes in the other groups (all P ＞ 0.05).No severe adverse reactions were observed during or after the treatment.Conclusion Microneedle intradermal injection with hyaluronic acid can effectively and safely improve erythema,skin pore and sensitive symptoms in patients with sensitive skin.

Microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin: a split-face study / 中华皮肤科杂志

Objective@#To evaluate clinical efficacy and safety of microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin.@*Methods@#A total of 53 female patients aged 21-54 years and diagnosed with sensitive skin were enrolled from Department of Cosmetic Dermatology, Dermatology Hospital of Southern Medical University from January to June in 2018, and were divided into 3 groups by using a random number generator and a residue-based method: high-pressure jet injection group (n = 23) receiving high-pressure jet injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with 0.9% sodium chloride solution on the left side of the face (control side) once every 2 weeks, microneedle injection group (n = 15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and microneedle-mediated injection with 0.9% sodium chloride solution on the left side of the face (control side) once every 4 weeks, combination group (n = 15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with hyaluronic acid on the left side of the face (control side) once every 4 weeks. All the patients in the above 3 groups received 4 consecutive sessions of treatment. Before the initial treatment and 2 weeks after the final treatment, erythema and skin pore scores were determined on the right and left sides of the face by using VISIA facial imaging system, lactic acid stinging test was performed, and skin sensitivity including severity of itching, dryness, erythema and scaling was evaluated. Two weeks after the final treatment, the overall improvement was evaluated with the Global Aesthetic Improvement Scale (GAIS) by clinicians and patients. Adverse reactions were recorded during and after treatment. Statistical analysis was carried out by using paired t test, Wilcoxon sign rank sum test and chi-square test.@*Results@#Two weeks after the final treatment, the improvement of skin pore score in the treatment side was superior to that in the control side in the high-pressure jet injection group (t = 2.19, P = 0.03) , while no significant difference in the improvement of erythema score was observed between the treatment side and control side (t = 1.10, P = 0.27) ; in the microneedle injection group, the improvement of erythema and skin pore scores was greater in the treatment side than in the control side (t = 2.47, 3.02, both P = 0.01) ; in the combination group, the VISIA erythema score in the treatment and control sides was 0.59 ± 0.25 and 0.85 ± 0.31 respectively, the improvement of erythema score in the treatment side was superior to that in the control side (t = 5.02, P < 0.01) , while there was no significant difference in the improvement of skin pore score between the treatment side and control side (P > 0.05) . Two weeks after the final treatment, the severity of itching, dryness and scaling was significantly improved in both the treatment and control sides in the 3 groups compared with those before the initial treatment (P < 0.05) , while the severity of erythema was significantly improved only in the treatment side in the microneedle injection group and combination group when compared with that before the initial treatment (Z = -2.236, -2.887, respectively, both P < 0.05) . Moreover, both the microneedle injection group and combination group showed significantly decreased severity of erythema in the treatment side compared with that in the control side two weeks after the final treatment (Z = -2.646, -2.887, respectively, both P < 0.05) . Two weeks after the final treatment, the positive rate of the lactic acid stinging test significantly decreased in the treatment side compared with that before the initial treatment in the microneedle injection group (χ2 = 4.821, P = 0.028) , but showed no significant changes in the other groups (all P > 0.05) . No severe adverse reactions were observed during or after the treatment.@*Conclusion@#Microneedle intradermal injection with hyaluronic acid can effectively and safely improve erythema, skin pore and sensitive symptoms in patients with sensitive skin.

Effect of high-pressure-jet processing on the viscosity and foaming properties of pasteurized whole milk.

The processing of milk using high-pressure technologies has been shown to dissociate casein micelles, denature whey proteins, and change the appearance and rheological properties of milk. A novel high-pressure processing technology called high-pressure-jet (HPJ) processing is currently being investigated for use in the food industry. Few studies have evaluated the effects of HPJ technology on dairy foods. The present study investigated the physicochemical and foaming properties of homogenized pasteurized whole milk processed at pressures from 0 to 500 MPa using HPJ processing. The apparent particle size exhibited a monomodal distribution in whole milk samples processed up to 125 MPa and a bimodal distribution for samples processed at 250, 375, and 500 MPa. The viscosity increased from approximately 2 to 5 mPa·s when whole milk was processed using HPJ at 375 MPa, and foam expansion increased from approximately 80 to 140% after processing at >125 MPa. Foam stability was limited to pressures in the 375 to 500 MPa range. We hypothesized that the increase in apparent particle size was due to the dissociation of casein micelles into surface-active casein protein monomers, and the formation of casein-casein and casein-fat particles. Ultracentrifugation of samples into 3 milk fractions (supernatant, serum, and precipitate), and subsequent fat and protein analysis on the 3 fractions, showed that a strong interaction between casein proteins and fat triglycerides occurred, evidenced by the increase in fat content associated with the precipitate fraction with increasing pressure. This suggests that stable casein-fat aggregates are formed when whole milk is processed using HPJ at pressure >125 MPa.