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Egg sausages, an essential component of traditional Chinese hot pot cuisine, have specific storage requirements and are predominantly distributed through refrigerated channels. A significant consideration in the freezing of egg sausages pertains to syneresis and textural modifications that manifest in the protein gel structure upon thawing. This research investigated the efficacy of incorporating whey protein isolate, soy protein isolate (at concentrations of 0.5%, 1.0%, and 2.0%), and modified cassava starch (at concentrations of 1.0%, 2.0%, and 3.0%) to enhance the textural integrity and mitigate syneresis in frozen egg sausage gels. The research demonstrated that syneresis in frozen egg sausages could be significantly minimized from 9.01% to 1.16% through the incorporation of 3% modified cassava starch and 2% whey protein isolate, to 2.01% with 1.0% soy protein isolate, and to 3.05% with 1.0% whey protein isolate. Furthermore, the combination of modified cassava starch (3%) and whey protein isolate (2%) demonstrated enhanced textural characteristics in frozen egg sausages with 20% additional water content following a 15-day storage period. Notably, egg sausages formulated with 0.5% whey protein isolate exhibited superior sensory attributes, including springiness, texture, and overall acceptability, compared to other formulations. The incorporation of whey protein isolate yielded markedly improved sensory characteristics relative to soy protein isolate additions. The findings indicate that the incorporation of whey protein isolate (0.5-1.0%) in conjunction with modified cassava starch (3%) effectively improves textural properties while reducing syneresis in thawed egg sausages.

Essential oils (EOs), regarded as secondary metabolites from plants, possess effective antibacterial properties. This study investigates the antibacterial efficacy of seven citrus EOs against six spoilage bacteria: Vibrio parahaemolyticus , V. harveyi , Photobacterium damselae , Shewanella putrefaciens , Carnobacterium divergens , and Lactobacillus pentosus . The antibacterial activity of these EOs was evaluated using solid- and vapor-phase applications. All tested EOs demonstrated effective antibacterial activity at a concentration of 294 μL/L against Gram-negative bacteria. Notably, lemon and orange EOs exhibited dose-dependent inhibition in both solid- and vapor-phase applications, with minimum effective concentrations ranging from 29.4 to 58.8 μL/L. Following treatment with lemon and orange EOs for 6 h at 1/4 minimum inhibitory concentration, leakage of intracellular DNA and proteins was observed, indicating damage to the cell membrane/wall. Proteomic analysis revealed distinct mechanisms: lemon EO impaired bacterial antioxidant defenses, while orange EO disrupted cell division, leading to reduced bacterial viability. These findings provide valuable insights into the potential of different EO application forms in controlling spoilage bacteria.

Traditionally, the processing of Gelidium seaweed into Gelidium jelly was very complicated, and involved repeated washing with water and sun drying for seven rounds. The seaweed, which is originally reddish-purple in color, turns yellow in color after the repeated washing and sun drying cycles. However, the sun drying process can only be used on sunny days. Therefore, this study evaluated an alternative method, halogen lamp drying, and compared the qualities of the product, Gelidium jelly, made using the halogen lamp drying and traditional sun drying methods. The properties investigated included the agar yield, gelling temperature, hardness, springiness, rheological parameters, sensory attributes, color, and volatile compounds. The results demonstrated that the halogen lamp drying method required 12 washing and drying cycles to achieve similar jelly properties to seven rounds of sun drying in the experimental conditions. Volatiles including heptanal, β-ionone, and (E)-2-decenal could be used as indicators to monitor the washing and drying processes. Halogen lamp drying could be an alternative processing method for seaweed drying, especially on rainy days.

The interactions among agar, gellan gum, gelatin, and modified waxy corn starch in the formation of mixed gels were examined in five different ratios. Binary hydrocolloid gels were prepared using three ingredients: two hydrocolloids (total hydrocolloid concentration: 0.5 wt%, ratios of mixture: 0/0.5, 0.1/0.4, 0.2/0.3, 0.3/0.2, 0.4/0.1, and 0.5/0) and water. The textural properties of the hydrocolloid gels were studied by measuring the gel strength, rigidity, breaking force, breaking point, and syneresis as functions of the mixing ratio. The higher syneresis percentage of binary modified waxy corn starch and gum gels than that of mixed gum gels after cold storage was mainly due to the retrogradation of amylopectin. Agar was shown be the most influential with regards to increasing the gel strength, breaking force, and rigidity among the three kinds of gum, while gellan gum was more effective against syneresis than agar and gelatin for storage periods of 7 and 14 days. In the mixed gels, a dramatic increase in the breaking point from 0 to 0.5% was only exhibited for gellan gum. The results provided useful information, including gel strength, rigidity, breaking force, breaking point, and syneresis, for gum and modified corn starch ingredients selected from refrigerated binary gum gels such as pudding for food product development.

This study examined the physicochemical effects of the fortification of noodles with 0.25-1.00% ( w / w ) calcium salts, viz. calcium acetate, calcium carbonate, calcium citrate, and calcium lactate. Fortification with calcium citrate, calcium acetate, and calcium carbonate increased the pH and breaking force of the dried noodles. However, the fortification of noodles with any concentration of calcium did not increase the extent of elongation of the control raw noodles. The L* and b* values of the raw and dried noodle color increased with increasing concentrations of calcium salts, except for noodles with added calcium citrate. Fortification with calcium citrate yielded no significant influence on color, texture, adhesiveness, springiness, flavor, and overall scores for cooked noodles. Noodles fortified with 0.5% calcium citrate made from oyster shells were compared with a control sample of noodles and noodles fortified with commercially available calcium citrate. The particle size of the calcium citrate made from oyster shells (258 nm) was smaller than that of the purchased calcium citrate (2631 nm). Noodles fortified with calcium citrate made from oyster shells showed no significantly difference compared to noodles fortified with commercially available calcium citrate. These results suggest that calcium citrate made from oyster shells may be used as the additive of choice for the manufacture of calcium-fortified noodles.

The World Health Organization indicated that antibiotic resistance is one of the greatest threats to health, food security, and development in the world. Drug resistance efflux pumps are essential for antibiotic resistance in bacteria. Here, we evaluated the plant phenolic compound ethyl 3,4-dihydroxybenzoate (EDHB) for its efflux pump inhibitory (EPI) activity against drug-resistant Escherichia coli . The half-maximal inhibitory concentration, modulation assays, and time-kill studies indicated that EDHB has limited antibacterial activity but can potentiate the activity of antibiotics for drug-resistant E. coli . Dye accumulation/efflux and MALDI-TOF studies showed that EDHB not only significantly increases dye accumulation and reduces dye efflux but also increases the extracellular amount of antibiotics in the drug-resistant E. coli , indicating its interference with substrate translocation via a bacterial efflux pump. Molecular docking analysis using AutoDock Vina indicated that EDHB putatively posed within the distal binding pocket of AcrB and in close interaction with the residues by H-bonds and hydrophobic contacts. Additionally, EDHB showed an elevated postantibiotic effect on drug-resistant E. coli . Our toxicity assays showed that EDHB did not change the bacterial membrane permeability and exhibited mild human cell toxicity. In summary, these findings indicate that EDHB could serve as a potential EPI for drug-resistant E. coli .

We have investigated different properties (thickness, moisture loss, oil uptake, breaking force, color, puffing ratio during 0.5-5 min frying, microstructure, and sensory evaluation) of raw pork skins with varying thickness (2, 3, and 4 mm) after drying, intended as deep-fried snacks. We have found that the oil content, breaking force, and puffing ratio of fried pork skin with different raw skin thickness have no significant difference under similar water content (1.68-1.98 g/100 g wet weight basis, wb) after 3-5 min of deep-frying at 180 °C. Additionally, sensory score results have shown that fried pork skins with 4 mm raw skin thickness had lower flavor, texture, and overall acceptability than those with 2 mm and 3 mm raw skin thickness. Scanning electron micrographs (SEM) have revealed less holes and irregular and crack microstructure in fried pork skins with 4 mm raw skin thickness than in other groups. Different thickness of raw pork skins resulted in different effects in microstructure and influenced water evaporation and oil uptake of fried pork skin. Finally, we have proposed the kinetic equations of water loss and oil uptake of fried pork skins. Fried pork skin from raw skin thicker than 4 mm need frying at temperature higher than 180 °C to improve their puffing ratio and sensory acceptability.

The fat content of fried pork rinds is high, and alternative frying helps reduce the oil content and maintain their texture and taste. Different frying methods such as microwave-assisted, traditional deep frying and vacuum frying on the breaking force, color, microstructure, water loss and oil absorption attributes of fried pork rinds were evaluated in this study. The fat content of microwave-assisted and vacuum-fried pork rinds was lower (24.2 g/100 g dry weight basis (db) and 17.1 g/100 g db, respectively) than that (35.6 g/100 g db) of traditional deep-fat frying. Non-uniform, holy and irregular surface microstructures were obtained by vacuum frying due to rapid mass transfer at low pressure. The first-order kinetic models of water loss and oil absorption of traditional and microwave-assisted frying of pork rinds were established. Microwave frying caused a faster moisture loss rate, shorter frying time and lower pork rind oil content, makes it an attractive substitute for traditional deep-fat frying.

Drug efflux pumps are one of the major elements used by antibiotic-resistant bacteria. Efflux pump inhibitors (EPIs) are potential therapeutic agents for adjunctive therapy, which can restore the activity of antibiotics that are no longer effective against pathogens. This study evaluated the seaweed compound diphenylmethane (DPM) for its EPI activity. The IC 50 and modulation results showed that DPM has no antibacterial activity but can potentiate the activity of antibiotics against drug-resistant E. coli . Time-kill studies reported that a combination of DPM and erythromycin exhibited greater inhibitory activity against drug-resistant Escherichia coli . Dye accumulation and dye efflux studies using Hoechst 33342 and ethidium bromide showed that the addition of DPM significantly increased dye accumulation and reduced dye efflux in drug-resistant E. coli , suggesting its interference with dye translocation by an efflux pump. Using MALDI-TOF, it was observed that the addition of DPM could continuously reduce antibiotic efflux in drug-resistant E. coli . Additionally, DPM did not seem to damage the E. coli membranes, and the cell toxicity test showed that it features mild human-cell toxicity. In conclusion, these findings showed that DPM could serve as a potential EPI for drug-resistant E. coli .

Multidrug efflux pumps play an essential role in antibiotic resistance. The conventional methods, including minimum inhibitory concentration and fluorescent assays, to monitor transporter efflux activity might have some drawbacks, such as indirect evidence or interference from color molecules. In this study, MALDI-TOF MS use was explored for monitoring drug efflux by a multidrug transporter, and the results were compared for validation with the data from conventional methods. Minimum inhibitory concentration was used first to evaluate the activity of Escherichia coli drug transporter AcrB, and this analysis showed that the E. coli overexpressing AcrB exhibited elevated resistance to various antibiotics and dyes. Fluorescence-based studies indicated that AcrB in E. coli could decrease the accumulation of intracellular dyes and display various efflux rate constants for different dyes, suggesting AcrB's efflux activity. The MALDI-TOF MS analysis parameters were optimized to maintain a detection accuracy for AcrB's substrates; furthermore, the MS data showed that E. coli overexpressing AcrB led to increased ions abundancy of various dyes and drugs in the extracellular space at different rates over time, illustrating continuous substrate efflux by AcrB. This study concluded that MALDI-TOF MS is a reliable method that can rapidly determine the drug pump efflux activity for various substrates.