Journal of Food Quality最新文献

Background. Even though foodborne illness is a worldwide concern, it is devastating in developing countries such as Ethiopia. Objectives. The objective of this study was to assess the food safety knowledge, attitudes, and practices of food handlers and the microbial profiles of food served at food establishments associated with Mekelle University in Ethiopia. Methods. A cross-sectional study was conducted among 332 food handlers working in food establishments at Mekelle University from January to May 2020. Quantitative data were collected using a structured interviewer-administered questionnaire and an observational checklist. Moreover, a total of 30 cooked food samples and 33 hand swab samples from 10% of the selected food handlers were collected to evaluate the microbial profile of the food. A multivariable logistic regression analysis was used to identify factors associated with the outcome variables. Results. In this study, 79.5%, 55.4%, and 37.7% of the food handlers had good knowledge, a positive attitude, and good practices towards food safety, respectively. Their poor self-reported food safety practices were clearly observed during their actual practices. The microbial profile result revealed that Staphylococcus aureus and Escherichia coli were identified in 13 (39%) and 27 (82%) of the food handlers’ hand swabs, respectively. Conclusion. This study indicated that food handlers working at these food establishments had poor attitudes and practices towards food safety and the microbial count of food samples was generally higher than the food safety standard. The safety of the food being produced and served in these restaurants will be greatly improved by regular supervision and retraining.

Nowadays, one-third of the world’s food production is wasted, so food industry has focused on the design of new technologies that contribute to preserving food quality and safety, focusing on environmentally friendly packaging. Polylactic acid (PLA) is a polymer which is biocompatible and biodegradable, of low cost, and generally recognized as safe (GRAS) by FDA; on the other hand, nanofibers obtained by electrospinning have the potential food industry application, for protection and release of bioactive compounds, producing active and intelligent packaging and increasing and monitoring food quality. The main objective of this work was to obtain food grade nanofibers (FGNs) of PLA (FGN-PLA) by electrospinning, for which different food grade solutions (FGSs) of PLA (FGS-PLA) concentrations with food grade solvent acetone (FGSA) were made and characterized via viscosity, density, conductivity, surface tension measurements, and rheological properties, and to correlate its effect on the FGN-PLA production by electrospinning as well as the effect of technique process parameters (distance from needle to collector plate and flow rate) on fiber characteristics was investigated. Morphological and dimensional characteristics of fibers were analyzed by SEM; increasing the FGS concentration as from 10% (w/v), beaded free and uniform nanofibers were produced. Also, average diameters increasing at higher polymer concentrations and flow rates. Rheological analysis indicates a Newtonian behavior, and the 10% (w/v) FGS shows stability for electrospinning process. In this paper, we report a detailed investigation of how electrospinning parameters interplay and affect FGN morphology and diameter that can be utilized for future research in food industry, for protection and release of bioactive compounds, as well as to maintain and monitor the food quality, as smart packaging systems.

3-Monochloropropane-1,2-diol (3-MCPD), 2,3-epoxy-1-propanol (glycidol), and their fatty acid esters are heat-induced food toxicants that have widely been investigated. This review study presents an overview of current knowledge about the dietary toxicity of 3-MCPD, glycidol, and their fatty acid esters. A literature search in two databases from January 2012 to December 2023 yielded 75 eligible articles for this review. The majority (73%) of the articles focused on 3-MCPD- and 3-MCPD fatty acid ester-induced toxicities. Nephrotoxicity (32%) was the most studied toxicity, whereas the least studied were carcinogenicity (4%) and hematotoxicity (4%). The metabolism of glycidol and its esters to 3-MCPD in the gastrointestinal tract remained a subject of contention as studies reported opposing findings. There was also new evidence of 3-MCPD-induced reproductive toxicity, hematotoxicity, and nephrotoxicity and 3-MCPD- and glycidol-induced neurotoxicity and genotoxicity. Findings suggest animal species-dependency in 3-MCPD’s carcinogenicity expression. Meanwhile, the 3-MCPD toxicity mechanism in obese rats is poorly understood. The review recommends further studies into the 3-MCPD toxicity mechanism in obese rats and the possible conversion of glycidol to 3-MCPD in gastrointestinal tracts.

Temperature control is critical to prevent overfermentation during the storage, distribution, and export of kimchi. Studies to optimize the freezing conditions for kimchi are lacking. Thus, the present study aimed to evaluate the optimum freezing and storage temperature for kimchi during long-term storage. Kimchi was frozen at −18°C, −40°C, and −80°C for 4 months, followed by thawing at 2°C until the core temperature reached 0°C. Thawing loss was maximum for samples frozen at −18°C, with increased cell membrane disruption, thus considerably decreasing the hardness. Compared to kimchi stored at −18°C, those frozen at −40°C and −80°C resisted the changes in pH, titratable acidity, reducing sugar content, antioxidant activity, and total phenol content. However, the total aerobic count and total lactic acid bacteria values of samples frozen at −18°C sharply decreased among treatments. Therefore, freezing at freezer temperature, particularly −80°C is ideal to maintain the kimchi quality for long-term storage.

Fruit juices can be enriched with plant extracts to enhance the nutritional and biological value of the product. Plant extracts are rich sources of bioactive compounds such as polyphenols with potential health benefits for consumers. In the present study, alginate microcapsules containing Eryngium billardieri (EB) extract (derived from aerial parts) were prepared and incorporated into apple juice. EB extract as nonencapsulated (NE), encapsulated (E) in microcapsules, and the combination of nonencapsulated + encapsulated (NE + E) at different concentrations of 1, 3, and 5% (w/v) were added to apple juice. These sample groups were stored at 4°C, and quality characteristics were evaluated for 21 days with a week of regular intervals. The results showed that the prepared microcapsules were spherical shaped with a size of 150–170 μm. The highest (75.12%) and the lowest (70.63%) encapsulation efficiency (EE) on the first day of storage were obtained in microcapsules containing 5% and 1% extract, respectively. EE decreased during storage time, and the lowest EE (65.25%) was observed in samples with 1% extract on day 21. Incorporation of E and NE + E extract improved total anthocyanin, total phenolic content, total flavonoid content, and antioxidant activity of apple juice due to the protective effects of the encapsulation on polyphenol compounds in the extract. After 21 days of storage, the highest (10.21%) and the lowest (5.85%) ascorbic acid contents were observed in samples with 5% NE + E t and control samples, respectively. Addition of EB extract to apple juice prevented the growth of yeasts and molds till day 7, and encapsulation of extract could enhance inhibitory activity. In terms of sensory acceptability, apple juices containing encapsulated extract received higher scores by panelists as a result of masking the unpleasant color and flavor of the extract. These results indicate that the application of EB microcapsules has potential for use in the food industry.

The purpose of this research was to assess the mineral content, bioactive compounds, α-glucosidase inhibitory activity, and antioxidant of two-maturity stages of corn silks, i.e., immature and mature with standard methods. Corn silks have been dried with sun and oven-drying methods and extracted through methanol and water, two individual solvents. The results revealed that both corn silks were good sources of mineral content. The higher calcium (13.37 ± 0.06) and magnesium (890.00 ± 0.00) were found in the sun-dried immature corn silk. The sun-dried mature corn silk also exhibited a higher content of iron, zinc, and manganese. The results also revealed that all the extraction systems yielded significant amounts of TPC, TFC, β-carotene, and anthocyanin content; ABTS and DPPH radical scavenging activity; and α-glucosidase inhibitory activity. Moreover, sun-dried methanolic extracts exhibited the highest levels of TFC (127.58 ± 7.95 mg QE/100 g DM), β-carotene (0.28 ± 0.00 mg/100 mL), TAC (42.53 ± 1.02 mg C3GE/kg DM), DPPH (75.65 ± 2.38%), and ABTS (94.22 ± 0.00%), showcasing their superior antioxidant potential. Conversely, oven-dried methanolic extracts demonstrated a higher TPC of 20.82 ± 0.62 mg GAE/g DM, while water extracts showed maximum α-glucosidase inhibitory activity of 76.19 ± 0.00%. Therefore, the obtained results demonstrated that sun-dried methanolic extracts from corn silks might be a good source of therapeutic agents and natural ingredients for manufacturing food, feed, and pharmaceutical products. It could also encourage researchers to carry out more studies to commercialize corn silk.

Foods fermented by lactic acid bacteria (LAB) are considered safer and healthier due to LAB’s ability to inhibit pathogen growth and produce bioactive compounds. The study aimed to evaluate the antimicrobial potential of lactic acid bacteria (LAB) in ice-kenkey, a chilled Ghanaian fermented maize beverage, against common foodborne pathogenic bacteria and to determine the duration of inhibition during ambient storage, all in the interest of promoting public health and safety. Samples of ice-kenkey obtained from a small-scale producer and ice-kenkey produced in the laboratory were inoculated with overnight pure cultures of Escherichia coli, Bacillus cereus, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella spp. in nutrient broth at concentrations of about 10⁸–10⁹ CFU/ml during storage at room temperature (≈27°C). The population of the different pathogens in both samples of ice-kenkey was enumerated at different storage periods to assess their survival in the ice-kenkey, hence the antimicrobial activity of the ice-kenkey. The pH of both types of ice-kenkey was below 5.0 throughout the storage period of up to 140 h. The commercial ice-kenkey had higher LAB and yeast counts. For both types of ice-kenkey, there was a steady increase in the population of LAB and yeasts from the 0 h to 72 h period, followed by a steady decline from the 96 h to the 120 h period. There were variations in the survival of the different enteric pathogens in the ice-kenkey samples. Vibrio cholera and Salmonella spp. were not detected in both types of ice-kenkey within 8–24 h of storage at room temperature. However, for Escherichia coli, Bacillus cereus, and Staphylococcus aureus, there were no significant reductions in their population within the first 8 h of the storage of both the laboratory and commercial ice-kenkey samples. This work demonstrated that the LAB in the ice-kenkey has remarkable inhibitory potential against both Gram-positive and Gram-negative pathogenic strains. In spite of this, producers need to minimise the risk of food-borne diseases through improved food safety and hygienic practices to prevent and inhibit the growth of microbial pathogens during retailing and storage.

The quality of vegetables depends upon the preharvest and postharvest practices. The preharvest practices include type, amount, form of fertilizers, harvesting period, growing season, and conditions that influence the yield of the crop and affect its chemical, biochemical, and mechanical properties. Moreover, postharvest practices such as storage conditions and processing methods also affect the quality of vegetables. Therefore, the present study was conducted to study the effect of different doses of nitrogen fertilizer (0–400 kg·N/ha) and storage conditions on the quality attributes of spinach leaves such as respiration rate, physiological loss in weight (PLW), chromatic properties, chlorophyll, puncture strength, TSS, pH, and nitrate during the storage studies. The respiration rate of leaves decreased with an increase in fertilizer dose. The a^∗and ΔE values of spinach leaves significantly (p < 0.01) increased with an increase in storage temperature (T) and storage time (t) and decreased significantly (p < 0.01) with an increase in fertilizer dosage (F). The puncture strength (PS) of leaves significantly (p < 0.01) decreased with an increase in F, T, and t. The T, t, and their interaction had a significant (p < 0.05) negative effect on the chlorophyll content of spinach leaves for all treatments. However, the T, t, and their interaction had a significant (p < 0.01) positive effect on pH and PLW and a negative effect on the nitrate content. The colour change, nitrate, and chlorophyll degradation were higher with storage time for leaves which have a higher amount of nitrate content initially. The TSS, pH, PLW, and mechanical properties degradation were higher with storage time for leaves that initially had a lower amount of nitrate content. Therefore, application of the recommended dosage (as per the soil nutrient status) of nitrogen fertilizer can produce leaves with minimum nitrate content, and storage of leaves under refrigerated conditions can enhance the shelf life.

The edible part of the prickly pear fruit is most commonly consumed, while the peel is often discarded, leading to the loss of valuable bioactive components, such as phenolic compounds. This research aims to assess the antioxidant activity, total phenolic content, and quantities of phenolic and flavonoid contents of fruit peel of Opuntia ficus-indica, Opuntia robusta, and Opuntia dillenii. Ten phenolic compounds were identified, with isorhamnetin being the most abundant flavonoid measuring 7184.09 μg/g, while sinapic acid was identified as the major phenolic acid measuring 1806.36 μg/g. Opuntia robusta exhibited the highest total phenolic content, total flavonoids, and total phenolic acids measuring 5583.19 mg GAE 100 g⁻¹, 21041.03 μg/g, and 3265.17 μg/g, respectively. Opuntia robusta and Opuntia dillenii demonstrated the higher antioxidant capacity in scavenging 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) compared to Opuntia ficus-indica, whereas Opuntia dillenii and Opuntia ficus-indica exhibited the highest concentration of antioxidants capable of reducing the Fe³⁺ complex of ferric ions (TPTZ)³⁺ to the ferrous complex Fe (TPTZ)²⁺. In contrast, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and total antioxidant capacity (TAC) assays showed no significant difference between the examined species. Compared to the local species Opuntia ficus-indica, the two newly introduced Dactylopius opuntiae-resistant species are richer in phenolic compounds and exhibit greater antioxidant activity.

Almond bagasse, a by-product derived from the production of almond vegetable drink, contains antioxidants, fibre, protein, and a high-fat content, presenting itself as a potential functional ingredient for the food industry. This study aimed to assess the powder derived from almond bagasse as a suitable alternative in the formulation of bakery goods. Various formulations substituting wheat flour with almond bagasse powder, obtained by air drying or freeze-drying at 10%, 15%, and 25%, were analysed in terms of technological and rheological properties. Furthermore, the physical and antioxidant attributes of biscuits with superior nutritional and functional values produced using these blends were examined. The results revealed significant changes in oil retention capacity, stability, and emulsifying activity, influenced by both the level of wheat flour replacement and the drying method used to obtain the almond bagasse powder. The most significant changes were observed in the emulsifying activity, which was zero in the wheat flour and showed values of 20% in the hot air-dried almond bagasse powder and 59% in that obtained by freeze-drying. In the blends, the values of this variable ranged from 1.8% to 7.1%. The highest value was obtained with a 25% replacement of wheat flour by freeze-dried almond powder. On the other hand, the lack of starch and the high concentration of fat (around 25%) and insoluble fibre (higher than 20%) in the almond bagasse powder determined the viscoelastic behaviour of the hydrated blends. As the percentage of substitution with the almond bagasse powder increased, the final viscosity decreased, being reduced from 2302 MPa·s in the wheat flour to 873 MPa·s in the blend containing 25% hot air-dried almond powder. It is worth noting that, the use of these blends for biscuit preparation resulted in a final product with a higher content of antioxidant components. The highest increase in antiradical capacity was 33% and was observed in the biscuits obtained with the mixture containing 25% hot air-dried almond powder.