Lactobacillus reuteri-fortified camel milk infant formula: Effects of encapsulation,in vitro digestion,and storage conditions on probiotic cell viability and physicochemical characteristics of infant formula

Lactobacillus reuteri fortified camel milk infant formula (CMIF) was produced. The effect of encapsulation in different matrices (sodium alginate and galacto-oligosaccharides) via spray drying, simulated infant gastrointestinal digestion (SIGID), and storage conditions (temperature and humidity) on the viability of L. reuteri in CMIF and the physicochemical properties of CMIF were evaluated. Compared with free cells, probiotic cell viability was significantly enhanced against SIGID conditions upon encapsulation. However, L. reuteri viability in CMIF decreased after 60 d of storage, predominantly at higher storage humidity and temperature levels. At the end of the storage period, significant changes in the color values were observed in all CMIF, with a reduction in their greenness, an increase in yellowness, and a wide variation in their whiteness. Moreover, pH values and caking behavior of all CMIF stored at higher temperature (40°C) and humidity [water activity (a_w) = 0.52] levels were found to be significantly higher than the samples stored under other conditions. Over 30 d of storage at lower humidity conditions (a_w = 0.11 and 0.33) and room temperature (25°C), no significant increase in CMIF lipid oxidation rates was noted. Fourier-transform infrared spectroscopy analysis showed that, compared with the other storage conditions, CMIF experienced fewer changes in functional groups when stored at a_w = 0.11. Microscopic images showed typical morphological characteristics of milk powder, with round to spherical-shaped particles. Overall, camel milk fortified with encapsulated L. reuteri can be suggested as a promising alternative in infant formula industries, potentially able to maintain its physicochemical characteristics as well as viability of probiotic cells when stored at low humidity levels (a_w = 0.11) and temperature (25°C), over 60 d of storage.     

New insights into the thermodynamics and kinetics of triacylglycerols crystallization

Understanding the transition from an isotropic liquid state to an organized crystalline state of triacylglycerols has great significance when designing lipid-based materials in general and food products in particular. In the current research, the balance between the demand for the tuning-fork (Tf) conformation, which is the suitable conformation for most crystalline organizations, and the supply of these molecules was discussed. Based on the negative dependency of the nucleation rates and the induction times on temperature, it was suggested that the limiting factor for the nucleation process is the conversion from the Tf conformation to any other conformation. On the other hand, based on the positive dependency of the melting temperatures and enthalpies on crystallization temperature, and the organized morphologies obtained at higher temperatures, it was suggested that the limiting factor during the crystal growth process is the conversion to the Tf conformation from another conformation.     

Crystalline lens thickness change is associated with axial length elongation and myopia progression in orthokeratology

AimsConsidering individual variability in regards to the effects of orthokeratology (ortho-k) on myopia progression and controversies regarding the precise underlying mechanism, the aim of this study was to investigate several ocular measurements associated with axial length (AL) growth in children wearing ortho-k lenses.MethodsIn this retrospective chart review, medical records of 53 Chinese children who wore ortho-k lenses over the course of 12 months were reviewed. Baseline variables included age at initiation of ortho-k wear, refractive error (spherical equivalent, SE), central corneal thickness (CCT), and flat and steep keratometry of corneal principal meridians. The change of anterior chamber depth (ACD) and the change of crystalline lens thickness (CLT) between baseline and the 12-month follow-up were also analyzed. The contributions of all analyzed variables to AL change were assessed using univariate and multivariate regression analyses.ResultsInitially, the results of paired t-test showed that CLT and AL were significantly increased after 12 months of ortho-k wear compared with that at baseline (P = 0.001 and < 0.001). The ACD did not change significantly after 12 months compared with that at baseline (P = 0.491). Subsequently, univariate analyses showed that a reduced rate of AL elongation was found in children who were older age at initiation of ortho-k wear (P = 0.028), had greater SE (higher degree of myopia) at baseline (p = 0.006), had thicker CCT at baseline (P = 0.04), and had greater increase of CLT (P = 0.001) in 12 months. At last, only greater SE (higher degree of myopia) and greater increase of CLT were associated with smaller increases of AL in multivariable analyses, (P = 0.003 and 0.001).ConclusionsBoth CLT and AL were significantly increased in children with overnight ortho-k wear after 12 months of follow-up. Greater baseline SE and greater increase of CLT were associated with less increase in AL during ortho-k wear in children with myopia.     

Effect of moderate electric field on structural and thermo-physical properties of sunflower protein and sodium caseinate

Moderate electric field (MEF) was employed to sunflower protein isolate (SPI) and sodium caseinate (CAS) to change their structural and thermo-physical properties with a non-thermal approach. MEF treatment significantly reduced the average particle size with noticeable changes in the uniformity of SPI and CAS solutions. A maximum of 10% reduction in the surface tension was observed for 0.2% w/w SPI sample by applying 150 V for 20 s. This effect was less pronounced for CAS samples and for the protein concentration of 2% w/w. FTIR spectra provided an increased α-helix content for SPI inducing a bulkier, loosened and more hydrophilic structure which is unlikely for CAS. Intrinsic Fluorescence Spectroscopy revealed that MEF treatments changed the tertiary structures of SPI and CAS. Denaturation temperatures and enthalpies of the SPI and CAS samples were decreased by MEF treatments.     

Emerging functional nanomaterials for the detection of food contaminants

Along with the progress in nanoscience, a variety of advanced functional nanomaterials were constructed to develop effective and innovative analytical techniques for food safety surveillance. In this review, we summarized the advanced analytical methods that have been developed based upon advanced functional nanomaterials, including plasmonic nanomaterial-based colorimetric methods, fluorescent nanomaterial-based fluorescent methods, advanced functional material-based molecular imprinting technology, advanced functional material-based chromatographic methods, plasmonic nanomaterial-based surface enhanced Raman scattering technology, and advanced functional material-based electrochemical methods. This review provides a progressive roadmap for further development of portable, rapid, and in situ detection technology to promote food safety surveillance from bench to market and eventually reduce the gap between research in the laboratory and industrial applications.     

Influence of temperature and environmental conditions on aflatoxin contamination in maize collected from different regions of Pakistan during 2016–2019

Aspergillus and their associated metabolites like aflatoxins (AFs) are one of the extremely significant contaminants that affect food production around the world. This species decreases yield and grains quality under suitable environmental conditions. AFs were identified in various food commodities, have been recognized as carcinogenic, mutagenic, teratogenic and immunosuppressive. From 2016 to 2019, a total of 324 samples of maize were obtained from diverse areas of Pakistan and examined for AFs level. AFs were determined using an HPLC validated method through post-column derivatization and fluorescence detection. This study also focused on the effect of climatic conditions on AF production. The total AFs (B₁+B₂+G₁+G₂) were detected in 267 (82.4%) samples, ranged between 0.69 and 356.7 μg/kg with a mean of 15.27 ± 0.82 μg/kg. A total of 182 (56.2%) and 85 (26.2%) samples had AFs level above the maximum acceptable limit as accepted by European Union (EU) and United States of America (USA), respectively. The outcomes of the existing study indicated that the climatic situations in the examined areas had a great impact on AFs contamination. Significant differences were found between AFs contamination levels in the samples collected in different months (p < 0.05). The most contaminated samples were identified in July, August and September as the climatic conditions favored the AF production. These outcomes suggested that the food commodities must be regularly examined in order to prevent the health of human and animal from the hazardous effects produced by AFs contamination.     

Immobilization of surface non-affinitive protein onto a metal surface by an external electric field

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