Smart nano-inks based on natural food colorant for screen-printing of dynamic shelf life of shrimp.

Intelligent packaging embedded with food freshness indicators can monitor food quality and be deployed for food safety and cutting food waste. The innovative nano-inks for dynamic shelf-life printing based on natural food colorant with application in real-time monitoring of shrimp freshness were prepared. Co-assembly of saffron petal anthocyanin (SPA) with hydrophobic curcumin (Cur) into chitin nano-scaffold (particle sizes around 26 ± 8 nm) could deliver hindering SPA leaching, confirmed by FT-IR, FE-SEM, AFM, and color stability test. The best response to pH-sensitivity was found in a ratio of (1:4) Cur/SPA (30% (v/w) in ChNFs that was correlated with the chemical and microbial changes of shrimp during shrimp freshness. However, smart screen-printed inks signified higher responsiveness to pH changes than FFI films. Therefore, smart-printed indicators introduced the excellent potential for a short response time, easy, cost-effective, eco-friendly, co-assembly, great color stabilities, and lifetime for nondestructively freshness monitoring foods and supplements.

Designing blenderized tube feeding diets for children and investigating their physicochemical and microbial properties and Dietary Inflammatory Index.

BACKGROUND: Due to the benefits of blenderized tube feeding (BTF) diets, the interest in using them is increasing. This study aimed to design BTFs for children and investigate their physicochemical and microbial properties, as well as Dietary Inflammatory Index (DII). METHODS: Five BTF diets were formulated mainly with fresh foods; their DII, physical (viscosity), and chemical (moisture, ash, protein, fat, energy, and micronutrients) characteristics were assessed. Also, the Hazard Analysis and Critical Control Points (HACCP) system was implemented for quality assurance of preparation, storage, and delivery of BTFs to patients in hospital. The microbial contamination (total count, Salmonella, Escherichia coli, Bacillus cereus, Listeria monocytogenes, coliforms, Staphylococcus aureus coagulase positive, mold, and yeast) was analyzed. RESULTS: Energy and percentages of protein, fat, and carbohydrate in BTFs were in the range of 103-112 kcal/100 ml, 16%-22%, 28%-34%, and 48%-52%, respectively. The viscosity of the five developed BTFs was between 29 and 64 centipoises, which allows the formulas to flow without syringe pressure. The DII of all BTFs was between -0.73 and -2.24. Due to the implementation of HACCP, monitoring the production line of BTFs, and performance of corrective measures, no microbial contamination was observed by indicator pathogenic microorganisms. CONCLUSION: A planned BTF diet can be an excellent selection for children using enteral nutrition with tube feeding especially when they are made from fresh and anti-inflammatory foods such as recipes prepared in this study.

Polyphenol-loaded bacterial cellulose nanofiber as a green indicator for fish spoilage.

Seafood products as a source of vitamins, minerals, and polyunsaturated fatty acids represent an important component of the human diet. However, they are susceptible to spoilage even under appropriate storage conditions, making it indispensable to develop freshness indicators. In this study, we introduce a green user-friendly pH indicator film for the naked-eye monitoring of fish spoilage. The pH indicator was prepared by successful loading of a mixture of anthocyanin and curcumin on bacterial cellulose (BC) nanofiber substrate. BC nanofiber with the advantages of biocompatibility, biodegradability, high purity, and superior mechanical strength was promising for generating pH-sensing arrays. The Fourier transform infrared (FT-IR) analysis proved the incorporation of anthocyanin and curcumin into the BC skeleton. Besides, the scanning electron microscopy (SEM) results clarified the morphology of the modified film by anthocyanin and curcumin. The pH indicator film was still stable after preserving for 60 days at different temperatures. The curcumin-anthocyanin loaded nanofiber indicated a distinct color change after spoilage by its exposure to fish meat in a transparent plastic package. Hence, the modified film by the anthocyanin-curcumin mixture is potent for the naked-eye monitoring of meat spoilage.

Millifluidic-assisted ionic gelation technique for encapsulation of probiotics in double-layered polysaccharide structure.

A unique double-layered vehicle was fabricated for the first time based on a millifluidic/direct gelation to encapsulate probiotics. Free probiotic bacteria are usually very sensitive to severe gastrointestinal conditions and maintaining their survival when passing through the digestive tract is essential. The effects of alginate concentration (20-30 g/L), flow rates of alginate (0.8-1.2 mL/min), and W/O emulsion (0.5-0.7 mL/min) on encapsulation efficiency (EE), size, and sphericity of core-shell millicapsules were optimized for encapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus plantarum. The optimized calcium-alginate millicapsule was spherical (0.97 ± 0.01 SF), with an average diameter of 4.49 ± 0.19 mm, and encapsulation efficiency of 98.17 ± 0.5 %. Two strains were encapsulated separately in W/O emulsion as a core of the millicapsule. After coating with chitosan, the encapsulation yield of the bacteria, survival rates under simulated gastrointestinal (GI) conditions, and viability during storage were determined. Survival efficiency of B. animalis subsp. lactis and L. plantarum after millifluidic encapsulation were found to be 92.33 and 90.81 %, respectively. Cell viability of encapsulated probiotics after passing through the GI system was improved (7.5 log CFU mL-1 for both strains). Although the viability of the encapsulated probiotics stored at -18 °C for five months significantly decreased (p<0.05), the number of live cells was approximately in accordance with the standard definition of long-term probiotic survival (6 log CFU/g). This work provides a pathway for the construction of an innovative delivery system with high efficiency and protective effects for probiotics.

Effect of maltodextrin with different dextrose equivalents on the physicochemical properties of spray-dried barberry juice (Berberis vulgaris L.).

Spray-drying technique is widely used in the production of powder from fruit juices. Carrier type and inlet temperature are two major factors that influence drying efficacy and powder quality. In this study, barberry juice (Berberis vulgaris L.) was powdered using 12% (w/v) maltodextrin with 4-7 and 16.5-19.5 dextrose equivalents (DEs) at two different inlet temperatures at 130 and 150 °C. Moisture content, bulk density, hygroscopicity, color, total anthocyanin content (TAC), microstructure, glass transition temperature and the X-ray diffraction of the prepared powders were investigated. The inlet temperatures and the utilization of maltodextrin with different DEs as the carrier agent, had different effects on the physicochemical properties of the prepared powders. By increasing the inlet temperature, the moisture content decreased while hygroscopicity increased. At inlet temperature of 130 °C, powders prepared with lower maltodextrin DEs had higher moisture content and bulk density, but lower hygroscopicity (p < 0.05). The SEM result demonstrated that, a decrease in color of the powder by increasing the inlet temperature. Darker particles with higher a* values and total anthocyanin contents (4.68 mg/g) were obtained when a larger amount of maltodextrin with lower DEs was utilized. At the lower inlet temperature, the powder particles had smoother surfaces. The glass transition temperature of the powders ranged from 47.1 to 54 °C based on different inlet temperature and DEs as well as moisture content. The amorphous surfaces of the dried particles were verified via X-ray diffraction profiling. Overall, applying different DEs in combination and lower inlet temperature led to the more appropriate physical and functional properties to the barberry powder. The TAC significantly depended upon the carrier agent, the inlet air temperature, and the interaction between the two variables.

Optimization of Gamma Aminobutyric Acid Production Using High Pressure Processing (HPP) by Lactobacillus brevis PML1.

In the present research, the production potential of gamma aminobutyric acid (GABA) using Lactobacillus brevis PML1 was investigated. In addition, the microorganism viability was examined in MAN, ROGOSA, and SHARPE (MRS) after undergoing high hydrostatic pressure at 100, 200, and 300 MPa for 5, 10, and 15 min. Response surface methodology (RSM) was applied to optimize the production conditions of GABA as well as the bacteria viability. Analysis of variance (ANOVA) indicated that both the independent variables (pressure and time) significantly influenced the dependent ones (GABA and bacteria viability) (P < 0.05). The optimum extraction conditions to maximize the production of GABA included the pressure of 300 MPa and the time of 15 min. The amount of the compound was quantified using thin-layer chromatography (TLC) and spectrophotometry. For the process optimization, a central composite design (CCD) was created using Design Expert with 5 replications at the center point, whereby the highest content of GABA was obtained to be 397.73 ppm which was confirmed by high performance liquid chromatography (HPLC). Moreover, scanning electron microscopy (SEM) was utilized to observe the morphological changes in the microorganism. The results revealed that not only did have Lactobacillus brevis PML1 the potential for the production of GABA under conventional conditions (control sample) but also the content of this bioactive compound could be elevated by optimizing the production parameters.

Biological detoxification of Monascus purpureus pigments by heat-treated Saccharomyces cerevisiae.

BACKGROUND: Today, there is an increasing concern about the consumption of synthetic colorants in food because of their possible health hazards. Monascus purpureus has attracted a great deal of attention as it produces various coloured pigments with high chemical stability, but it also produces citrinin, a secondary toxic metabolite, along with the pigments. This study aims to investigate the amount of pigment and citrinin reduction by different treatments with Saccharomyces cerevisiae such as heat treatment and suspension concentration. RESULTS: The results indicated that the ability of S. cerevisiae regarding citrinin adsorption increased with increase of temperature and yeast concentration. The maximum extent of citrinin adsorption was related to heat treatment at 121 °C and a yeast concentration of 105 cells mL-1 , for which citrinin reduced from 4.43 mg L-1 in control to 0.1 mg L-1 . Heat treatment of 103 cells mL-1 suspension of S. cerevisiae cells at 50 °C, with 0.56 mg L-1 citrinin remaining in the medium, showed the lowest ability for citrinin binding. The optimum absorbance of all red, orange and yellow pigments was observed for the heat treatment at 50 °C and yeast concentrations of 103 and 104 cells mL-1 which was greater than that for the control. CONCLUSIONS: We can conclude from this study that heat treatment with S. cerevisiae can be a useful way to reduce citrinin to below the standard limits. © 2019 Society of Chemical Industry.

Preparation and Characterization of Herbicide Mecoprop Imprinted Polymer and Its Application as a Selective Sorbent in Water Sample.

Bulk polymerization method was used to prepare a homogeneous molecularly imprinted polymer (MIP) for the specific extraction of herbicide mecoprop (MCPP). Thereafter, the binding performance of this functional polymer was evaluated under optimal condition, compared to a non-imprinted polymer. From the Scatchard plot analysis, two types of binding sites were detected in the MIP, the high affinity binding sites with a KD (equilibrium dissociation constant) of 6.4 µM and the low affinity ones with a KD of 55.9 µM. In addition, the possibility of using synthesized MIP for MCPP extraction from environmental aqueous samples was explored. The adsorption capacity of MIP in spiked bottled water and groundwater samples showed that the polymer could effectively extract MCPP from bottled water and groundwater (p < 0.05) with the recovery of 70.5% and 65.1%, respectively, demonstrating the potential of imprinted polymers for cost-effective and effective water treatment.

Immobilization of Saccharomyces cerevisiae on Perlite Beads for the Decontamination of Aflatoxin M1 in Milk.

Aflatoxin M1 (AFM1) contamination presents one of the most serious concerns in milk safety. In this study, the immobilization of Saccharomyces cerevisiae was used to detoxify AFM1-contaminated milk. The yeasts were immobilized on perlite for 24 and 48 hr, and the best immobilization time was achieved at 48 hr. Microscopic examination confirmed successful immobilization. The milk samples with 0.08, 0.13, 0.18, and 0.23 ppb AFM1 contamination were passed through the biofilter for 20, 40, and 80 min. The results showed a significant reduction in AFM1 concentration for all the milk samples with various initial AFM1 contents. The contaminated milk with 0.08 ppb AFM1 was completely cleared after 40 min of circulation while for the milk solution with 0.23 ppb, the highest AFM1 reduction was obtained at about 81.3% after 80 min circulation. In addition, the biofilter was saturated after the third step of milk circulation, containing 0.23 ppb AF, in which each step duration was 20 min. This study showed the excellent capability of the immobilized cells on the perlite beads to detoxify the AFM1-contaminated milk without any side effects on its physicochemical properties. PRACTICAL APPLICATION: The immobilization of Saccharomyces cerevisiae cells on perlite beads can be used to detoxify AFM1-contaminated milk. The perlite can provide a perfect support for immobilization. With respect to qualitative properties, 20 min, was suggested as the optimum time for milk decontamination. This study indicated that the detoxification of contaminated milk using immobilized S. cerevisiae cells on the perlite support did not affect the different properties of detoxified milk. This method can lead to a practical solution to address aflatoxin contamination in dairy products considered high-risk foods.

Electrospray-assisted drying of live probiotics in acacia gum microparticles matrix.

Acacia gum solution was employed as a carrier for electrospray-assisted drying of probiotic cells. To optimize the process, effect of gum concentration, thermal sterilization as a prerequisite for microbial studies, and surfactant addition on physical properties of feed solution was investigated. Increasing gum concentration from 20 to 40 wt.% led to a viscosity increase, whilst surface tension did not change meaningfully and electrical conductivity declined after an increasing trend up to 30 wt.% of the gum. Thermal sterilization increased the viscosity without any significant effect on the conductivity and surface tension. Surfactant addition reduced the surface tension and conductivity but the viscosity increased. Highly uniform particles were formed by electrospray-assisted drying of autoclaved 35 wt.% acacia gum solution containing 1 wt.% Tween 80. Thermal sterilization and surfactant addition improved electrospray-ability of acacia gum solution. Bacterial count showed that more than 96 percent of probiotic cells passed the process viably.

Principles of electrospraying: A new approach in protection of bioactive compounds in foods.

Electrospraying is a potential answer to the demands of nanoparticle fabrication such as scalability, reproducibility, and effective encapsulation in food nanotechnology. Electrospraying (and the related process of electrospinning) both show promise as a novel delivery vehicle for supplementary food compounds since the process can be carried out from an aqueous solution, at room temperature and without coagulation chemistry to produce matrices or particulates in the micro- and nano-range. The presentation of core materials at the nanoscale improves target ability to specific areas of the digestive tract and gives improved control of release rate. Adoption of these electrohydrodynamic atomization technologies will allow the industry to develop a wide range of novel high added value functional foods. To optimize production conditions and maximize throughput, a clear understanding of the mechanism of electrospraying is essential. This article presents a comprehensive review of the principles of electrospraying to produce nanoparticles suitable for food technology application, particularly for use in encapsulation and as nanocarriers.