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This research aimed to valorize almond hulls based on a zero-waste strategy towards sustainable agricultural developments for the recovery and production of valuable compounds. For this purpose, the potential to produce four products, including pectin (AHP), phenolic compounds (AHPC), pullulan (PUL), and single-cell protein (SCP), was examined. The acidic extraction factors were optimized using a Box-Behnken design for the simultaneous extraction of AHP and AHPC, and the obtained results showed that the maximum AHP (26.32% w/w) and AHPC (6.97% w/w) yields were achieved at 90 °C, pH of 1.4, 58.65 min, and liquid-solid ratio (LSR) of 20.13 v/w as the optimum point. In the next step, the solid residues that remained from the AHP and AHPC extraction process (PESR) were treated with cellulase enzyme and ultrasound and were used for simultaneous microbial production of PUL (34.29-24.56 g/L) and biomass containing SCP (19.31-13.44% w/w). Furthermore, the obtained results showed that AHP was low methylated (26.40%), rich in galacturonic acid (67.88%), and high in molecular weight (595.299 kDa). Also, the investigations of structural properties of AHP and PUL confirmed the presence of chemical structures of these polysaccharides in the formed supernatants. In addition, the AHPC showed considerable antioxidant activity compared with ascorbic acid (ASC) and BHA.

Enterotoxigenic methicillin-resistant Staphylococcus aureus (MRSA) is considered as one of the common foodborne pathogens. The existing research was performed to investigate the distribution of enterotoxigenic and antibiotic resistance genes of MRSA bacteria that are isolated from raw poultry meat samples. Two-hundred and sixty poultry meat samples were cultured and MRSA bacteria were recognized using cefoxitin and oxacillin susceptibility test. Antibiotic resistance and enterotoxigenic gene profiles were studied using PCR test. Prevalence of MRSA amongst poultry samples was 5%. Chicken (12%) had the highest prevalence rate, while ostrich (1.66%) had the lowest. Total distribution of sea, seb, sec, sed and see enterotoxin encoding genes were 50%, 25%, 8.33%, 75% and 8.33%, respectively. BlaZ (100%), aacA-D (58.33%), tetK (58.33%), msrA (58.33%) and dfrA1 (50%) were the most regularly detected antibiotic resistance-encoding genes. Concurrent presence of enterotoxins and antibiotic resistance-encoding genes in MRSA bacteria stipulates important public health matters regarding the consumption of contaminated chicken, turkey, quail and ostrich meat.

This study aimed to hydrolyze lentil protein from two hydrolysis stages: single and sequential hydrolysis using Alcalase (1, 2, and 4% w/w enzyme to substrate (E:S)) and Flavourzyme (2% w/w) through a processing time of 180 min with an interval of 30 min, and then, degree of hydrolysis (DH), antioxidant and angiotensin-converting enzyme (ACE)-inhibitory activities, phenolic compounds, amino acid composition, molecular weight (MW) distribution, molecular weight profile, sensory, and functional properties were evaluated. The highest DH (47.05%), ACE-inhibitory (0.25 mg/mL), and phenolic compounds (3.84 mg GAE/g) were obtained when sequential hydrolysis was accomplished at Alcalase and Flavourzyme concentrations of 2% w/w and hydrolysis time of 120 and 60 min, respectively. Hydrolysis did not change the main amino acid profile. Despite this, the amino acids which contribute to umami taste were increased after hydrolysis. According to Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) results, the lowest MW peptides were produced by sequential hydrolysis which was agreed by gel permeation chromatography (GPC) (4.4 kDa and 100 Da). Sensorial analysis indicated that peptides produced by Alcalase at 1% w/w concentration with hydrolysis time of 180 min (Al-1%-180 min, DH value of 15.72%) had the highest bitter taste and further hydrolysis led to reduction of bitter taste and sweetness was increased for Flavourzyme (Fl-2%-180 min) and also sequential hydrolysis produced peptides. Alcalase digests indicated higher solubility than control and Flavourzyme digest. The emulsifying activity index (EAI) was decreased (35.2 to 21.5%) while Foaming capacity (FC) was increased (80 to 104.76%) by Alcalase hydrolysis.

The study aimed to formulate a high protein base as a dysphagia food and investigate the possibility of textural modification by applying microwave treatments. The formulated mixture contained 41.7% pea protein (dry basis), which exhibited shear thinning behavior. The application of microwave processing at 300, 500, and 700 W for 60, 120, and 180 s showed that at a higher level of energy induction by microwave, the hardness of the sample gradually increased from a fluid gel to a soft solid and more rigid levels. Processing at 300 and 500 W in the tested range showed that textural properties (hardness, adhesiveness, cohesiveness, springiness, gumminess, and chewiness) of the sample could be modulated within the recommended criteria for dysphagia food, providing the possibility of individualization of food texture for dysphagia disorder. Two main causes of these textural changes could be water evaporation and protein denaturation, in which, regarding the ratio of water evaporation to the size of textural changes, protein denaturation was thought to have the main impact on the phenomena.

In this study, kefiran was esterified with octenyl succinic anhydride (OSA). The esterification reaction variables including pH (8.5), kefiran concentration (5% (w/w)), OSA concentration (12% (w/w)), temperature (~38 °C) and reaction time (~80 min) were found as optimum points to achieve the maximum degree of substitution (DS) (0.041 ± 0.002). Kefiran-OSA samples with DS of 0.021 (FDA suggested DS) and 0.041 (maximum DS) were prepared and compared with unmodified kefiran in all experiments. FTIR and 1H NMR spectroscopies proved the grafting of OSA on kefiran structure. XRD analysis revealed that with increase in DS, the physical state of kefiran to be more amorphous. In addition, the esterification modification led to a decrease in the degradation temperature and an increase in the apparent viscosity based on the obtained data from thermal analysis and viscosity measurement. The results of the foaming and emulsifying properties confirmed the improvement in surface properties of the modified kefiran. The frequency sweep test illustrated that with an increase in DS, the viscoelastic behavior of the kefiran cryogels to be more viscous. It can finally be stated that the modification with OSA was a high potential strategy to extend the industrial applications of the kefiran.

Pullulan (PU) is an exo-polysaccharide used in the food and pharmaceutical industries. However, the use of PU in different industries is limited due to its highly hydrophilic nature and consequently weakness in surface properties which can be remedied by its chemical modification with octenyl succinic anhydride (OSA). For this purpose, PU modification with OSA was optimized and the results showed that the maximum degree of substitution (0.061 ± 0.003) was obtained under pH of 9.0, pullulan concentration of 40% (w/w), temperature of ~40.90 °C, reaction time of ~101.21 min and OSA concentration of 14.96% (w/w). Also, the grafting of OSA on pullulan structure was confirmed by FTIR, 1H NMR and zeta-potential analyzes. Although this modification had no significant effect on the amorphousity of pullulan, it led to an increase in viscosity and a decrease in decomposition temperature and surface tension. Improvement of emulsifying properties of PU-OSA sample was proved by the evaluation of emulsifying capacity of un- and modified samples and also, zeta-potential, particle size and viscosity of the prepared emulsions. In line with surface characteristic results, an increase in foam capacity of modified samples was observed with decreasing the interfacial tension.

In this study, encapsulation of ursolic acid (UA) in electrosprayed gelatin nanoparticles and structural modification of the particles through adjusting solution properties was carried out. Atomization of a gelatin solution without UA resulted in smooth particles with mean diameter of 570.1 ± 299.3 nm; however, upon the addition of UA, the particles developed with irregular morphologies and the mean diameter increased to 752.3 ± 706.3 nm. Modification of the particle characteristics using sodium dodecyl sulfate and ammonium oxalate resulted in particles with improved morphology uniformity, mean diameter of 702.8 ± 182.8 nm and encapsulation efficiency of ∼87%. FTIR spectra pointed to stabilization of UA in nanoparticles through establishing hydrogen bonds with gelatin molecular chain. XRD patterns showed that upon encapsulation, UA crystalline nature was changed to a more amorphous state. DSC thermograms illustrated that the nanoparticles would be able to maintain stability at the temperatures up to ∼90 °C. Release studies suggested that the encapsulation extended the release period and decelerated the release rate of UA in PBS solution, and improved its bioaccessibility by 945.58% at the end of simulated gastrointestinal tract. The overall results demonstrate the successful enhancement of particle characteristics and also suggest that electrosprayed gelatin nanoparticles could be a suitable carrier for UA.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is considered to be one of the most important causes of foodborne diseases. Objective: The current examination was performed to examine the distribution of staphylococcal cassette chromosome mec (SCCmec) and Panton-Valentine leukocidin (PVL) gene amongst the MRSA strains isolated from raw fowl meat samples. Materials and Methods: A total of 240 fowl meat samples were collected and cultured. MRSA strains were identified using cefoxitin and oxacillin susceptibility tests. DNA samples extracted from the MRSA strains were subjected to polymerase chain reaction (PCR) for detection of SCCmec and PVL gene. Results: Twenty-two out of 240 (9.16%) raw fowl meat samples were positive for S. aureus strains. Twelve out of 22 S. aureus strains (54.54%) were determined as MRSA strains. The incidence of MRSA strains in raw chicken, turkey, quail, and ostrich meat samples was 66.66%, 50%, 50%, and 33.33%, respectively. The incidence of SCCmec IVa, SCCmec IVd, and SCCmec V was 50%, 8.33% and 41.66%, respectively. The applied method failed to detect SCCmec types I, II, III, IVb, and IVc. The incidence of the PVL gene amongst the MRSA strains was 75%. Conclusion: The presence of SCCmec IV and SCCmec V and PVL gene revealed occurrence of community-associated MRSA (CA-MRSA) in fowl meat samples. Further studies are required to find additional epidemiological aspects of the MRSA strains in fowl meat samples.

This study aimed to design mixed hydrogels composed of whey protein aggregates (WPA)/k-carrageenan with a tailored microstructure to protect curcumin within the upper gastrointestinal tract and deliver it to the colon. Curcumin was loaded in WPA and followed by cold gelation of the aggregates in the presence of k-carrageenan. The Microstructure of the hydrogels varied from homogenous to protein continuous or k-carrageenan continuous depending on the k-carrageenan concentration (0.0, 0.1 and 0.55%, w/w). The physical stability of curcumin toward precipitation during gelation of curcumin-loaded WPA was significantly improved after k-carrageenan addition. The higher capacity of k-carrageenan containing gels to curcumin entrapment was attributed to curcumin embedment inside of the rich-protein microdomains (called microgels), higher viscosity of the gel pre-solutions contained k-carrageenan and the shorter gelation time of the corresponding gels. Moreover, it was found about 31% of the loaded curcumin was released in the simulated gastrointestinal tract for pure WPA gels, while after addition of 0.55% k-carrageenan to WPA gels, more than 87% of loaded curcumin were delivered to the colon. Besides, 33% of curcumin degraded after the gastrointestinal digestion, while for WPA gels containing 0.1% and 0.55% k-carrageenan it was only 9.6% and 3.5%, respectively. The results were attributed to the protective effect of k-carrageenan to protein during in vitro digestion so that the access of digestive enzymes into the hydrogels was limited resulting in a reduction of gel matrix erosion and curcumin release. Therefore, curcumin remained bound to the protein and was not damaged during digestion until it reaches the colon.

In this study, to improve the water resistance properties of pullulan (PU) edible-films, the combination of the modification with octenyl succinic anhydride (OSA) and beeswax (BW) incorporation was used. The FTIR spectra results confirmed the PU octenylsuccination and also the presence of the BW in the composite films. The scanning electron microscopy (SEM) micrographs showed that the PU modification with OSA powerfully retarded the coalescence of BW droplets in film casting process and led to their homogeneity in the dried films. Also, the findings indicated that the water-proof properties including water solubility, water vapor permeability and water contact angle in the PU films were improved by the PU modification and BW incorporation. In addition, the obtained data showed that the octenylsuccination of PU had a negative effect on the mechanical properties of the produced films, while BW incorporation into PU-OSA films led to resolve this drawback.

Currently, the only effective treatment for celiac disease is the complete avoidance of gluten. The quality and texture represents a major technological challenge in gluten-free products, due to the absence of the visco-elastic gluten compound. The present study determines the effect of chickpea protein isolate (CPI) (0–7%), transglutaminase (MTG) (0–1.5%) and xanthan gum (0–0.6%) on the rheological characteristics and quality attributes of gluten free millet muffins using the response surface methodology (RSM). The results showed that xanthan increased the specific volume and porosity and decreased the hardness by increasing its concentration, while the addition of CPI and MTG in lower levels had a different effect than that in higher levels. MTG and CPI at first decreased specific gravity and then increased it. Xanthan increased this property at all concentrations studied. Browning index of crust decreased with the addition of xanthan and CPI and increased with the addition of MTG. Finally, it can be concluded that it was possible to form a protein network in the gluten-free muffins with the addition of MTG and CPI. However, the efficiency of the enzyme was dependent on both the protein content and the level of enzyme concentration.

Microwave assisted extraction technique was used to extract pectin from sour orange peel. Box-Behnken design was used to study the effect of irradiation time, microwave power and pH on the yield and degree of esterification (DE) of pectin. The results showed that the optimum conditions for the highest yield of pectin (29.1%) were obtained at pH of 1.50, microwave power of 700W, and irradiation time of 3min. DE values of pectin ranged from 1.7% to 37.5%, indicating that the obtained pectin was low in methoxyl. Under optimal conditions, the galacturonic acid content and emulsifying activity were 71.0±0.8% and 40.7%, respectively. In addition, the emulsion stability value ranged from 72.1% to 83.4%. Viscosity measurement revealed that the solutions of pectin at low concentrations showed nearly Newtonian flow behavior, and as the concentration increased, pseudoplastic flow became dominant.

This paper aims to investigate chemical composition, rheological behavior, antioxidant activity and functional properties of Cordia myxa mucilage (CMM). Response surface methodology (RSM) demonstrated that optimum conditions for CMM extraction were as follow: ultrasound power of 99.37 W, extraction temperature of 88.05 °C and solid to water ratio of 16.25 w/w. CMM had, on average, 77.51% carbohydrate, 5.86% total ash, 8.90% protein, 6.90% moisture, and 1.00% fat. Due to a high level of nutrients, CMM can be suggested as a value added by-product in food and pharmaceutical systems. CMM is a low molecular weight polysaccharide containing three fractions with various molecular weights. FT-IR spectrum illustrated that this polymer had all typical bands and peaks characteristics of polysaccharides. Based on steady shear measurements, CMM can be introduced as a new source of hydrocolloid with high-temperature stability. CMM had the desirable antiradical capacity, water solubility and water/oil holding capacity.

Nanostructured colloidal delivery systems comprising of pectin-coated nanoliposomes (pectonanoliposomes) were developed as carriers for a bioactive polyphenolic compound (phloridzin). Phloridzin-loaded nanoliposomes were fabricated using a heating-stirring-sonication method, and coated with low methoxyl pectin using an electrostatic deposition approach. Dynamic light scattering, micro-electrophoresis, atomic force microscopy, and UV-Visible spectroscopy were used to investigate the impact of system composition on the size, charge, morphology and stability as well as immobilization, adsorption and encapsulation efficiencies of the pectonanoliposomes. Response surface methodology was used to optimize the composition of the pectonanoliposomes based on particle size and charge characteristics. Linear, quadratic and interaction effects of 1,2-dioleoyl-3-trimethyl ammonium propane/lecithin, phloridzin/lecithin and pectin/liposome ratios significantly influenced the mean hydrodynamic diameter and/or surface charge of pectonanoliposomes. Second-order polynomial regression models were generated for intensity-weighted particle size and zeta potential of the designed carriers. Topographic and phase contrast images showed that pectonanoliposomes exhibited a range of different morphologies. Coating the nanoliposomes with pectin improved their immobilization and encapsulation efficiencies as well as physical storage stability. Cationic pectonanoliposomes were superior to plain systems regarding long-term stability. Our results suggest that pectonanoliposomes may be suitable delivery systems for polyphenolic nutraceuticals, such as phloridizin, in functional food and pharmaceutical applications.

A model low-fat salad dressing including salep as thickening agent was prepared. In order to obtain an stable salad dressing, different variables each one at three levels like salep content (0.5, 2.0, and 3.5% w/w), oil volume fraction (7.50, 16.25, and 25.00% w/w), pH (3, 5, and 7), salt concentration (0.3, 0.9, and 1.5% w/w), and egg yolk content (2, 4, and 6% w/w) were chosen and their effect on the creaming index of salad dressing was studied. It was observed that samples with highest salep content at pH 3 were the most stable during storage time (15 days). The microstructure of some samples was considered. Rheological measurements were performed for stable samples. Oil fraction and salt content increased zero shear viscosity and G′ modulus of samples.

In this study, the effects of fat (0.5 %, 3.2 % and 5.0 %), inulin (0.0 and 1.0 %) and starter culture (0.0 %, 0.5 %, 1.0 % and 1.5 %) on the angiotensin converting enzyme (ACE)-inhibitory activity of probiotic yogurt containing non-viable bacteria were assessed. Proteolytic activities of bacteria were also investigated. Yogurts were prepared either using a sole yogurt commercial culture including Streptococcus thermophilus and Lactobacillus delbrueckii subs. bulgaricus or bifidobacterium animalis BB-12 and Lactobacillus acidophilus La5 in addition to yogurt culture. Relative degrees of proteolysis were found to be considerably higher in yogurt samples than UHT milk as the control. Both regular and probiotic yogurts showed considerable ACE-inhibitory activities. Results showed that degree of proteolysis was not influenced by different fat contents, while was increased by high concentration of starter culture (1.5 % w/w) and reduced by inulin (1 % w/w). ACE-inhibitory activities of yogurt were also negatively affected by the presence of inulin and high levels of fat (5 % w/w). Moreover, yogurt containing probiotic bacteria showed higher inhibitory against ACE in comparison to the yogurt prepared with non-probiotic strains.

Summary Effects of different levels of fat and inulin on bacterial cell counts, degree of proteolysis and concentrations of organic acids in the yogurt containing inactivated cells of probiotic strains Bifidobacterium animalis and Lactobacillus acidophilus were investigated. Results showed that both L. acidophilus and B. animalis grew well in the yogurt samples reaching cell counts higher than 106 CFU mL−1 at the final pH of 4.5. Inulin at the concentration of 1% had no significant effects on the production of organic acids and cell counts of L. acidophilus, but promoted the growth of B. animalis with a reduction in the degree of proteolysis. Generally, different fat levels showed significant effects on the production of organic acids and nonsignificant effects on the cell counts of probiotic bacteria and degree of proteolysis. In case of lactic acid, the ratio of L- (+)to D- (−) isomer ranged from 50/50 to 80/20 in yogurt samples.

Coacervation between sodium caseinate (CAS) and low methoxyl pectin (LMP) at pH 3 was investigated as a function of protein/polysaccharide ratio. The highest amount of complex coacervates was formed at a CAS/LMP ratio of 2 at which the ζ-potential value was zero and the turbidity reached its highest value. Then, the properties of films based on these complex coacervates were studied. Coacervation resulted in decreasing water content and water sorption of films as the protein concentration increased. The mechanical properties of films were highly influenced by the formation of electrostatic complexes. The highest values of Young's modulus (182.97± 6.48MPa) and tensile strength (15.64±1.74MPa) with a slight increase of elongation at break (9.35±0.10%) were obtained for films prepared at a CAS/LMP ratio equal to 0.05. These findings show that interactions between LMP and CAS can be used to develop innovative packaging containing active molecules.

This study examined the feasibility of using kefiran, an exopolysaccharide obtained from kefir grains, as a new film-forming material. Kefiran-based films, with and without glycerol as plasticizer, were prepared by a casting and solvent-evaporation method. To study the impact of the incorporation of glycerol into the film matrix, physical, mechanical, and thermal properties of the films were investigated. As expected, the increase of glycerol concentration from 15% to 35% w/w increased extensibility but decreased tensile strength, implying higher mobility of polymer chains by the plasticizing effect of glycerol. Water vapour permeability of films was found to increase as the plasticizer content increased. Glass transition temperatures decreased as a result of plasticization as glycerol content increased. The properties of the films were related to their microstructure, which was observed by scanning electron microscopy. Thus, it was observed that plasticizer is a significant factor in the properties of these films and their food technology applications.

Fat cell distribution in the structure of semimembranosus muscle of goat and lamb was studied. The effect of various heating methods including conventional, domestic and industrial microwave were investigated using fluorescent light microscopy. Frequency used for microwave heating was 2450 MHz with two wattages levels of 700 (domestic microwave) and 12000 (industrial microwave). All samples were heated to internal temperature of 70 °C. The roasted samples in conventional oven were compared with microwave cooking. Fat distribution was different in various heat treatments. The roasted samples had greater fat retention in semimembranosus muscle. Results showed that uneven distribution of fat in muscle system influenced fat loss during cooking. The fat cells in the interior of muscle were lost more slowly compared to the fat located near the surface of the muscle. The overall migration of fat globules during microwave cooking was higher than conventional cooking.

Two types of synbiotic ice cream containing 1% of resistant starch with free and encapsulated Lactobacillus casei (Lc-01) and Bifidobacterium lactis (Bb-12) were manufactured. The survival of L. casei and B. lactis were monitored during the product’s storage for 180 days at −20 °C. The viable cell number of L. casei and B. lactis in the free state in prepared ice cream mixture was 5.1 × 109 and 4.1 × 109 CFU/mL at day one and after 180 days storage at −20 °C, these numbers were decreased to 4.2 × 106 and 1.1 × 107 CFU/mL, respectively. When we encapsulated the mentioned probiotic bacteria in calcium alginate beads, the probiotic survival raised at rate of 30% during the same period of storage at same temperature. In general, the results indicated that encapsulation can significantly increase the survival rate of probiotic bacteria in ice cream over an extended shelf-life. The addition of encapsulated probiotics had no significant effect on the sensory properties of non-fermented ice cream in which we used the resistant starch as prebiotic compound.

New edible composite films based on kefiran and oleic acid (OA) at the ratio of 15, 25, and 35% (w/w) were prepared using emulsification with the aim of improving their water vapour barrier and mechanical properties. Film-forming solutions were characterized in terms of rheological properties and particle-size distribution. The impact of the incorporation of OA into the film matrix was studied by investigating the physical, mechanical, and thermal properties of the films. The water vapour permeability (WVP) of the emulsified films was reduced by approximately 33% by adding OA. The mechanical properties of kefiran films were also affected by adding OA: tensile strength was diminished, and elongation increased considerably. Differential scanning calorimetry showed that the glass transition temperature (Tg) of the kefiran film was −16 °C and was not considerably affected by adding OA. Therefore, OA could be incorporated into these films for some food-technology applications that need a low affinity toward water.