Effect of edible chitosan film enriched with anise (Pimpinella anisum L.) essential oil on shelf life and quality of the chicken burger

In this study, the effect of chitosan film (CF) with different concentrations of anise essential oil AEO (0, 0.5, 1, 1.5 and 2%) on the quality of chicken burger during chilled storage (4 + 1°C) were examined over a period of 12 days. For this purpose, at the first, the physical and mechanical properties of the produced films were studied. Then, the chicken burger was covered with the produced films. Different treatment were analyzed by biochemical properties such as moisture and thiobarbituric acid, bacteriological properties such as total viable counts and total psychrotrophic counts, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli. The results of this study showed that adding AEO improved the properties of CF, the moisture, solubility, and water vapor permeability decreased in these films. By increasing the concentration of AEO the tensile strength and elasticity of film were increased. CF with AEO, delayed lipid oxidation in chicken burger and improved the chemical properties of chicken burger. Also, microbial spoilage in these samples decreased significantly (p < .05) compared to the control sample. AEO at 2% in all experiments had better results than other treatments (p < .05), and the AEO (1.5% and 2%) had acceptable biochemical, bacteriological attributes up to end of storage, and these treatments could reduce the population of pathogen bacteria below the acceptable level from day 3 until the end of the storage period. Sensory score of the treatment containing AEO at 1.5% was higher than the sensory score of AEO at 2%. Overall, the results of this study showed that the use of CF with AEO as a natural preservative increased the shelf life of meat products. Considering the relatively similar anti‐oxidation and antimicrobial effect of AEO at 1.5 and 2% and also economic aspects, optimum dose for AEO could be 1.5% in the film.

Shelf-life extension of whole shrimp using an active coating containing fish skin gelatin hydrolysates produced by a natural protease

This study was focused on shelf-life extension of whole shrimp (Penaeus merguiensis) using an active coating containing gelatin hydrolysates. Gelatin extracted from Scomberomorus commerson skin was hydrolyzed using actinidin extracted from kiwifruit. Some important physicochemical characteristics of fish skin gelatin including viscosity, gelling and melting points, and temperatures were examined. The whole shrimp was coated with four coating agents including fish skin gelatin (FG), commercial gelatin (CG), fish skin gelatin containing 1 mg/ml fish gelatin hydrolysates (FG + GH), and commercial bovine gelatin containing 1 mg/ml fish gelatin hydrolysates (CG + GH). Chemical, microbial, and sensorial properties of samples were monitored for 12 days at 4°C with 3-day intervals (0-12 days). The pH value of samples coated with FG + GH and CG + GH showed the lowest changes during 12 days of storage (1.68 ± 0.00 and 1.70 ± 0.09, respectively). The free fatty acid content (FFA), total volatile base nitrogen (TVB-N), lipid oxidation, and carbonyl content of samples coated with FG + GH and CG + GH were significantly lower than that of control, CG, and FG samples. The results of this study showed that the gelatin hydrolysates could be used as a preservative costing agent for whole shrimp.

Shelf-life enhancement of whole rainbow trout (Oncorhynchus mykiss) treated with Reshgak ice coverage

The effect of ice coverage comprised of Reshgak extract and Reshgak essential oil on shelf-life extension of chilled whole rainbow trout (Oncorhynchus mykiss) was evaluated. Chemical (peroxide value (PV), thiobarbituric acids (TBA), total volatile nitrogen base (TVB-N), and free fatty acids (FFA)), microbiological (total viable count (TVC) and psychrotrophic viable count (PVC)), and sensory evaluations (texture, color, flavor, and general acceptance) were investigated every 4 days during a 20-day storage period. Results revealed that the effect of both icing systems led to considerably lower bacterial counts and chemical indices in comparison with the traditional ice coverage without such phytogenic. According to sensory analyses, fish stored in ice containing Reshgak essential oil had a longer shelf-life (>16 days) and those stored in ice medium included with Reshgak extract possessed a shelf-life of 16 days, whereas lot stored in traditional ice showed a shorter shelf-life of 12 days.

Influence of polysaccharide-based edible coatings on enzymatic browning and oxidative senescence of fresh-cut lettuce

Fresh-cut lettuce has a short shelf-life due to enzymatic browning and oxidative senescence. The present study investigated effects of polysaccharide-based edible coatings (alginate, chitosan, and carrageenan) on enzymatic browning and antioxidant defense system of fresh-cut lettuces during cold storage (4°C) for 15 days. The results showed that three coatings could inhibit enzymatic browning through maintaining total phenolics (TP) content and decreasing polyphenol oxidase (PPO) and phenylalanine ammonialyase (PAL) activities. These coatings also reduced phospholipase D (PLD) and lipoxygenase (LOX) activities, lowered malondialdehyde (MDA) content, and enhanced antioxidant enzymes (superoxide dismutase, SOD; peroxidase, POD; catalase, CAT; ascorbate peroxidase, APX) activities. Besides, all coatings positively affected sensory properties of fresh-cut lettuces after 3 days storage. Additionally, among three coating treatments, chitosan coating had the most positive effects on quality of fresh-cut lettuce and was the most suitable coating for retarding enzymatic browning and alleviating membrane oxidative damage. These results indicated that polysaccharide-based edible coatings were helpful to maintain quality, inhibit enzymatic browning, and postpone senescence of fresh-cut lettuce.

Effects of chitosan-based coatings on storage quality of Chinese shrimp

We investigated the effects of chitosan-based coatings on the preservation quality of refrigerated Chinese shrimp for 12 days. Samples of Chinese shrimp were subjected to three different coating treatments, namely chitosan (CH), chitosan and ε-polylysine (CH + ε-PL), chitosan combined with ε-polylysine and carrageenan (CH + ε-PL + CA), and compared with a control. The bacteriological characteristics [total viable count (TVC)], chemical indexes including pH, thiobarbituric acid (TBA) value, K-value, and total volatile basic nitrogen (TVB-N), texture (hardness, chewiness, and elasticity), and sensory changes were assessed. The increases in TVC, pH, TBA, K-value, and TVB-N were observed to be delayed by preservation treatments, and the textural and sensory characteristics indicated that the treated shrimp were preserved more effectively than the control. Treatment with chitosan combined with ε-polylysine and carrageenan was the most effective preservation method than treatment with chitosan alone or chitosan and ε-polylysine; the shelf life was also prolonged. Therefore, treatment with chitosan combined with ε-polylysine and carrageenan is proposed as a potential method for shelf life extension of Chinese shrimp for refrigerated storage.

Guidance on date marking and related food information: part 1 (date marking)

A risk-based approach was developed to be followed by food business operators (FBO) when deciding on the type of date marking (i.e. 'best before' date or 'use by' date), setting of shelf-life (i.e. time) and the related information on the label to ensure food safety. The decision on the type of date marking needs to be taken on a product-by-product basis, considering the relevant hazards, product characteristics, processing and storage conditions. The hazard identification is food product-specific and should consider pathogenic microorganisms capable of growing in prepacked temperature-controlled foods under reasonably foreseeable conditions. The intrinsic (e.g. pH and aw), extrinsic (e.g. temperature and gas atmosphere) and implicit (e.g. interactions with competing background microbiota) factors of the food determine which pathogenic and spoilage microorganisms can grow in the food during storage until consumption. A decision tree was developed to assist FBOs in deciding the type of date marking for a certain food product. When setting the shelf-life, the FBO needs to consider reasonably foreseeable conditions of distribution, storage and use of the food. Key steps of a case-by-case procedure to determine and validate the shelf-life period are: (i) identification of the relevant pathogenic/spoilage microorganism and its initial level, (ii) characterisation of the factors of the food affecting the growth behaviour and (iii) assessment of the growth behaviour of the pathogenic/spoilage microorganism in the food product during storage until consumption. Due to the variability between food products and consumer habits, it was not appropriate to present indicative time limits for food donated or marketed past the 'best before' date. Recommendations were provided relating to training activities and support, using 'reasonably foreseeable conditions', collecting time-temperature data during distribution, retail and domestic storage of foods and developing Appropriate Levels of Protection and/or Food Safety Objectives for food-pathogen combinations.

Polyphenols from halophytes and modified atmosphere packaging improve sensorial and biochemical markers of quality of common dolphinfish (Coryphaena hippurus) fillets

Quality and shelf‐life of whole and filleted Coryphaena hippurus, stored with modified atmosphere packaging (MAP) and natural antioxidants from halophytes (HAL), were investigated. Fillets were divided into control, simply sealed in trays; MAP, preserved by modified atmosphere (45% CO₂, 50% N₂, 5% O₂); and MAP‐HAL, pretreated with antioxidants and preserved by MAP. Whole and filleted fish were stored at −1 ± 0.5°C for 18 days. The quality of the samples was analyzed at the time of packaging and after 3, 6, 9, 12, 15, and 18 days. The MAP and MAP‐HAL groups maintained the best sensorial profile, pH, and drip loss with respect to the untreated fillets. Higher levels of total volatile basic nitrogen (TVB‐N) and oxidized proteins were observed in untreated samples with respect to the MAP and MAP‐HAL groups. The principle component analysis revealed a different quality profile for untreated and MAP‐treated fish.

Oxidative stability of direct-expanded chickpea-sorghum snacks

In contrast to other pulses, chickpea has a relatively high fat content (3%-10%). This study was designed to investigate direct-expanded chickpea-sorghum extruded snacks (50:50, 60:40, and 70:30 chickpea:sorghum, w/w) with respect to: their oxidative stability and sensory properties during accelerated (55°C) and room temperature (25°C) storage; correlations between chemical markers (peroxide value and p-anisidine value) and sensory data during accelerated storage; and the shelf-life of snacks extruded at the optimal expansion point as determined by a rotatable central composite design. Peroxide values and p-anisidine values were in the range of 0-2.5 mEq/Kg and 5-30, respectively, for both accelerated and room temperature storage, and increased during storage (p < .05). 70:30 and 60:40 (w/w) chickpea-sorghum snacks had higher peroxide and p-anisidine values compared to the 50:50 snack during storage at either temperature (p < .05). Rancid aroma and off-flavor of 60:40 and 70:30 chickpea-sorghum snacks (slightly intense = 6) also were higher than that of the 50:50 snack (moderately weak = 3) (p < .05). Significant correlations (p < .05) were found between chemical markers and sensory attributes (p < .05). The study illustrated that shelf-life decreased as the percentage of chickpea in the blend increased. Therefore, in terms of shelf-life, a 50:50 chickpea-sorghum blend is preferable.

Probiotic yogurt supplemented with nanopowdered eggshell: Shelf-life stability, physicochemical, and sensory characteristics

The objectives of this study were to produce probiotic yogurt (5.0-7.0 log cfu/g) fortified with nanopowdered eggshell (NPES) at a rate of 0.02, 0.04, and 0.06 mg/ml, as well as, examine the effect of NPES on the physicochemical, microbial, sensory properties, and shelf-life of probiotic yogurt. The NPES was prepared by milling preboiled dried eggshell using a mortar grinder. The size of the milled powder was measured to assure that the diameter of the powder is 27 ± 1.7 nm. Yogurt was manufactured by dividing the pasteurized milk into four aliquots portions. The first portion was utilized as control (T1), while the other three portions were supplemented with 0.02 (T2), 0.04 (T3), and 0.06 (T4) mg/ml NPES. All treatments were inoculated with 5.11 log cfu of Lactobacillus delbruckii ssp. bulgaricus (Lb) and Streptococcus thermophilus (St) combined and 5 log cfu of Bifidobacterium bifidum (Bb) per kg of milk at 40°C until the pH of 4.6 was reached. The acidity, sensory properties, Bb count, total bacterial count (TBC), yeast, and mold counts were examined. The results showed that the acidity was increasing during storage, however, increasing NPES resulted in low acid development (p < .05). The shelf-life of control was ended after 8 d of storage at 4°C because molds were grown on the surface of the sample. The TBC significantly decreased (p < .05) as the concentration of NPES increased. Bb count in probiotic yogurt was also decreasing during storage. Yeast and molds were detected in control after 8 d; however, NPES did not result in molds even after 16 d of storage but yeast was exhibited. The NPES improved the sensory evaluation of probiotic yogurt slightly and increased the shelf-life of probiotic yogurt as compared to control.

A novel process to improve the characteristics of low-fat ice cream using date fiber powder

The objective of this study was to improve the characteristics of low-fat ice cream (LFIC) using date fiber powder (DFP). DFP was added to LFIC mix (3% fat, 14% milk solids nonfat, 15% sucrose, 0.3% stabilizer, and 0.1% vanilla) at a rate of 1.5%, 2.5%, and 3.5%. Control treatment with no DFP was also manufactured for comparison. The LFIC mix was analyzed for physicochemical and microbiological analyses. After manufacture, microbiological, rheological, and sensory characteristics of LFIC were evaluated during storage at -18˚C for 30 days. The addition of DFP to the LFIC mix led to increasing (p < .05) the density and weight per gallon (lb) of final product. Thus, a 3.5% of DFP led to increasing the density of LFIC from 0.6 to 1.0 g/cm3 and weight per gallon from 5.2 to 9.0 lb, while the overrun of LFIC was decreased (p < .05) from 50.0% to 24.0%. Additionally, the melting resistance of LFIC made with DFP was higher (p < .05) as compared to control. Approximately 60% of LFIC made with DFP was melted after 50 min compared to 100% in control. The total bacterial count (TBC) and yeast and molds' count slightly increased in LFIC with adding DFP. However, there was a slight decrease in these counts during storage for 30 days. Psychrotrophic and coliform bacteria were not detected in the LFIC. Organoleptically, LFIC made with DFP showed higher scores (p < .05) of body and texture, melting quality, and appearance as compared to control during the 30 days of storage. However, the flavor was slightly decreased (p < .05) as the concentration of DFP was increased. The overall scores were increased with increasing the DFP concentrations up to 15 days as compared to control, followed by a decrease at 30 days of storage.

Nutritive quality prediction of peaches during storage

Peaches (Prunus persica L. Batsch) are commonly consumed fruits with high nutritional value. We evaluated the nutritive qualities of peach fruit during storage. Heatmap analysis showed that protein, ash, and crude fiber contents clustered together, whereas fat and reducing sugars clustered separately. We then classified the nutrients into two clusters; cluster 1 showed low fat and reducing sugar levels and high protein, crude fiber, and ash levels, whereas cluster 2 showed high fat and reducing sugar levels and low protein, cruder fiber, and ash levels. Partial least squares regression and random forest analyses showed accuracies of 67% and 61%, respectively. Spectra at 1,439 and 1,440 nm indicated reducing sugars, and the spectrum at 2,172 nm indicated protein. Thus, Fourier transform-near infrared spectroscopy could predict the two clusters based on five nutritive qualities. Our findings may help to establish guidelines for promoting the acceptability of peach fruits among consumers.

Determination of the microbial community of traditional Mongolian cheese by using culture-dependent and independent methods

Mongolian cheese is not only a requisite source of food for the nomadic Mongolian but also follows a unique Mongolian dairy artisanal method of production, possessing high nutritional value and long shelf-life. In this study, the ancient technique for the production of Mongolian cheese was investigated. The nutritional value of Mongolian cheese was characterized by its high-protein content (30.13 ± 2.99%) and low-fat content (9.66 ± 3.36%). Lactobacillus, Lactococcus, and Dipodascus were the predominant bacterial and fungal genera, and Lactobacillus helveticus, Lactococcus piscium, and Dipodascus geotrichum were the predominant species in the Mongolian cheese. The microbiota of products from different cheese factories varies significantly. The high-temperature (85°C-90°C) kneading of coagulated curds could eliminate most of the thermosensitive microorganisms for extending the shelf-life of cheese. The indigenous spore-forming microbes, which included yeasts, belonging to Pichia and Candida genera, and molds, belonging to Mucor and Penicillium genera, which originated from the surroundings during the process of cooling, drying, demolding, and vacuum packaging could survive and cause the package to swell and the cheese to grow mold. The investigation of production technology, nutrition, microbiota, and viable microbes related to shelf-life contributes to the protection of traditional technologies, extraction of highlights (nutritional profiles and curd scalding) for merchandise marketing, and standardization of Mongolian cheese production, including culture starters and aseptic technique.

Functional instant noodle formulation for emergency conditions: Sensory and stability characteristics

The aim of this study was to evaluate the shelf-life and sensory characteristics of a functional instant noodle preparation designed to be used in emergencies as a tactical ration. Instant noodles were selected for their global acceptability and ease of preparation. In this study, semolina flour was used as the main ingredient, and soy protein isolate was added to increase the protein content. Additionally, green tea and beef tallow were incorporated to decrease the likelihood of oxidation. Carboxymethyl cellulose was added to increase the porosity and water absorption of the dry noodles. Spirulina powder was used as a dressing for the final product before serving to increase the nutritional value and provide the consumer with the required vitamins and minerals of the day. Physical, chemical, and organoleptic properties were assessed at multiple timepoints in a 120-day period to perform an accelerated shelf-life test by determining their critical moisture content and moisture sorption isotherm curves at 30, 45, and 55°C. The shelf-life of the product was evaluated to be 1197.28 days at 30°C and 75% relative humidity in aluminum pouches. In conclusion, the product is shelf-stable at room temperature and is recommended to be stored and used in disaster conditions such as earthquakes, floods, and wars.

Effect of dietary fat on proximal composition, sensorial analysis and shelf life of a traditional Spanish cooked pork product "Lomo de Sajonia" from Iberian pork

This study aims to evaluate the effect of different dietary fat sources on the quality of a Spanish-cooked meat product Lomo de Sajonia (LSA) and its shelf-life. Forty loins were selected from Iberian pigs fed four dietary treatments containing pork fat (G-1), Greedy-Grass Olive® (GGO) (enriched oleic-acid oil) (G-2), G-2 and high oleic sunflower (G-3), and G-3 plus a mixture of commercial organic acids (Bioll®) (G-4). Loins were manufactured to obtain LSA, and the quality and sensorial attributes were assessed. The shelf life was established according to microbial count and sensorial analysis, which was packed in a modified atmosphere and stored under retail conditions. All meat quality parameters of LSA remained stable in all groups, except fat content and overall liking, which showed the highest values for G-2 LSA. Regarding the shelf life, sensorial attributes remained acceptable in all groups during storage time, while a delay in microbial growth was recorded for the LSA of G-3. According to the results, including GGO in Iberian pig diets could enhance LSA traits, possibly linked to increased assimilation compared with conventional fat sources. However, adding organic acids to the diet did not have the expected effect on improving the shelf life of the LSA.

Evaluating the effects of hypoxic storage on platelet function and health using a novel storage system

BACKGROUND

Thousands of units of whole blood (WB) and blood components are transfused daily to treat trauma patients. Improved methods for blood storage are critical to support trauma-related care. The Hemanext ONE® system offers a unique method for hypoxic storage of WB, with successfully demonstrated storage of clinically viable RBCs. This work evaluated the system for the storage of WB, focusing on platelet health and function.

STUDY DESIGN AND METHODS

WB was collected from healthy donors and processed through the Hemanext ONE® system. Hemoglobin oxygen saturation (HbSO2) levels of WB were depleted to 10%, 20%, or 30% of total HbSO2 and then stored in PVC bags sealed in oxygen-impermeable bags (except for normoxic control) with samples collected on days 1, 7, and 14 post-processing. Flow cytometry assessed the activation and apoptosis of platelets. Clot dynamics were assessed based on aggregometry and thromboelastography assays, as well as thrombin generation using a calibrated-automated thrombogram method.

RESULTS

Hypoxic storage conditions were maintained throughout the storage period. Hypoxia triggered increased lactate production, but pH changes were negligible compared to normoxic control. Storage at 10% HbSO2 had a significant impact on platelet function, resulting in increased activation and reduced clot formation and aggregation. These effects were less significant at 20% and 30% HbSO2.

DISCUSSION

This study indicates that platelets are sensitive to hypoxic storage and suffer significant metabolic and functional deterioration when stored at or below 10% HbSO2.

Long-term stability of extra virgin olive oil: effects of filtration and refrigeration storage on the Kolovi variety

BACKGROUND

The composition of extra virgin olive oil (EVOO) defines its sensory, nutritional, and human health benefits, and distinguishes it as a key component of the Mediterranean diet. Nevertheless, EVOO constituents are susceptible to degradation during processing and storage, which reduces the olive oil's quality and limits its shelf life. The present study investigated the effect of molecular filtration before storage and the effect of cool storage at 4 °C on the stability of 'Kolovi' EVOO, a variety originating from the Greek island of Lesvos, over a 24 month period.

RESULTS

Storing EVOO at 4 °C positively affected free acidity, peroxide value, K268, fruity qualities, and concentrations of hydroxytyrosol, tyrosol, ligstroside aglycone, lutein, and squalene, in comparison with the control sample stored at room temperature, particularly after 1 year. Molecular filtration significantly affected the ratio of unsaturated fatty acids to saturated fatty acids (UFAs/SFAs). Optimal preservation of parameters such as acidity value and lutein content was achieved by combining molecular filtration with refrigeration.

CONCLUSIONS

The present study recommends storing EVOO in the refrigerator for up to 18 months. Based on the regulatory limits of the quality characteristics of acidity, peroxide value, K232 value and fruity sensory attributes, the shelf-life of the protected geographical indication (PGI) 'Kolovi' EVOO can reach 2 years under cool storage (4 °C) and with molecular filtration before storage. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Enhancing shelf-life and nutritional value of broccoli florets through vacuum impregnation with calcium chloride and ascorbic acid

BACKROUND

The present investigation aimed to enhance the postharvest shelf-life of broccoli using vacuum impregnation (VI). Broccoli florets were impregnated with physiologically active chemicals, i.e. calcium chloride and ascorbic acid. Post-impregnation broccoli florets were packed in three different packaging materials (poly(ethylene terephthalate) punnets, low-density polyethylene pouches and shrink-wrap film) and stored at two temperatures (5 and 25 °C). The effects of impregnation solutions, packaging materials and storage temperature on physicochemical attributes (weight loss, total soluble solids, ascorbic acid, total chlorophylls and carotenoid content), antioxidant and phenolic contents, and shelf life were studied. The changes in the chemical structure post-impregnation and during storage were investigated using Fourier transform infrared (FTIR) spectroscopy.

RESULTS

Results showed that impregnated broccoli florets exhibited significantly (P < 0.05) higher levels of biochemical attributes immediately after impregnation. During storage, the physicochemical and antioxidant properties of broccoli florets declined for all the samples. However, the reduction in these properties was significantly (P < 0.05) lower in impregnated florets as compared to untreated control samples. Principal component analysis and FTIR results also indicated a clear difference in the impregnated and control samples. The shelf-life of broccoli florets stored at 25 °C was assessed as 4 and 3 days for impregnated and control samples, respectively; whereas the samples stored at 5 °C had a shelf-life of 12 days for impregnated samples and 5 days for the control samples. The findings of the study elucidate the potential of VI in enhancing the initial quality and shelf-life of broccoli.

CONCLUSION

The deterioration during storage is primarily due to physiological weight loss, a natural loss of water and volatile compounds that occur following harvest due to transpiration and respiration. Excessive transpiration can lead to dehydration, which reduces the quality and shelf-life of the product. © 2024 Society of Chemical Industry.

Studying the shelf life of butter containing fucoidan, by evaluating sensory and chemical properties

Fucoidan powder was added in amounts of 0.05, 0.1,0.3, and 0.5% to sour cream butter and sensory and chemical properties were tested on their shelf life for 60 days during storage. Peroxide levels initially increased until day 40 of storage and then decreased. Butter samples from the control group had the highest amount of peroxide on day 40 (15.25 ± 1.41 meq/kg butter), while samples treated with fucoidan 0.5% had the lowest amount of peroxide (6.35 ± 0.53 meq/kg butter). The acidity of butter treatments increased during storage (p < .05). Butter samples from the control group had the highest acidity at 60 days of storage (0.40 ± 0.033 mg KOH / g butter), while samples treated with 0.5% fucoidan had the lowest acidity (0.17 ± 0.013 mg KOH / g butter). The treated butter samples showed the highest stability. Fucoidan, as an antioxidant, reduces the taste, odor, and discoloration of butter added with fucoidan during storage because it completely removes odorless tasteless powder, and the free radical chain is involved in oxidation and improves product properties. The results showed that there are no significant changes in the acceptance rate of butter treated with fucoidan during 60 days of storage in the refrigerator (p > .05). The sensory scores of the treated butter showed that the sensory properties during the storage period were similar to the control samples, but on day 40 of storage, they decreased. In general, a concentration of 0.5% fucoidan delays the oxidative process and increases shelf life and is selected as a superior treatment in terms of sensory evaluation, and is introduced as a functional food.

Physicochemical properties of Kakol (Suaeda aegyptiaca) essential oil nanoemulsion and its effect on the storage quality of rainbow trout (Oncorhynchus mykiss) during cold storage

The study aims to analyze the chemical composition of Suaeda aegyptiaca essential oil (PSAE) by GC-MS, produce the nanoemulsified essential oil (NSAE) using ultrasound, and compare the antimicrobial and antioxidant activity of the PSAE and NSAE in laboratory medium and rainbow trout fish (Oncorhynchus mykiss). Geranyl-acetone (30.52%) and p-Vinylguaiacol (10.66%), and (e)-β-ionone (7.79%) were the main PSAE chemical compounds. The mean droplet size diameter, polydispersity index, and viscosity of NSAE were 179.67 nm, 0.255, and 0.96 cP, respectively. PSAE and NSAE showed a moderate antiradical potential against DPPH- and ABTS-free radicals (50 < IC50 < 250 μg mL-1). There was no significant difference between antiradical scavenging of PSAE and NSAE (p > .05). E. faecalis and K. pneumonia were the most and lowest sensitive bacteria to PSAE and NSAE, respectively. Examining different treatments on the shelf-life of minced fish showed that Kakol essential oil could improve the shelf-life of fish between 12.5% and 60% (depending on quality index). There was no significant difference between the bioactivity of PSAE and NSAE, which means that the nanoemulsion showed acceptable performance at lower essential oil concentrations.

Variations in quality attributes of pulsed light-treated table grape juice during refrigerated storage (4°C) and ambient conditions (25°C)

Pulsed light (PL) pasteurization is being explored as a substitute for the conventional thermal pasteurization of juices in recent times due to better retention of nutrients and overall quality. However, the long-term stability of the PL-pasteurized juice must be investigated to promote its application by the industry. The effect of PL treatment (effective fluence of 1.15 J·cm-2) and thermal treatment (90°C for 60 s) on microbial quality, enzyme activity, bioactive compounds, sensory acceptance, and color profile of table grape juice during storage at 4 and 25°C was investigated in this study. The PL pasteurization enhanced the microbial shelf-life of the juice (<6 log10cfu·mL-1) from 5 to 35 days at 4°C. The PL and thermally-pasteurized juice demonstrated a shelf-life of only 10 days when stored at 25°C. The total soluble solids and titratable acidity did not alter significantly throughout the storage period. The peroxidase, polyphenol oxidase, and pectin methylesterase activities were below 10% for the PL and thermally-treated beverage when stored at 4°C. The sensory acceptability of the PL-pasteurized juice after 35 days of refrigerated storage (6.9 ± 0.3) was close to the untreated juice (7.2 ± 0.3) and greater than thermally-treated juice (6.2 ± 0.2). After the 35th day of storage at 4°C, PL-treated grape juice retained 55%, 12%, and 15.3% more phenolics, flavonoids, and antioxidant capacity, respectively, than the thermally-pasteurized juice. Hence, PL pasteurization can effectively prolong the shelf-life of table grape juice while achieving microbial and enzymatic stability, along with high sensory and nutritional appeal. PRACTICAL APPLICATION: Exploring non-thermal methods like pulsed light (PL) pasteurization as a substitute for conventional thermal methods is gaining recognition for its ability to retain nutrients and improve overall juice quality. However, the industry's adoption depends on understanding the shelf-stability of PL-pasteurized juice. This study specifically investigates the practical applications of PL treatment in comparison with conventional thermal treatment in enhancing microbial safety and enzymatic stability in table grape juice. The findings contribute insights into optimizing the shelf life of table grape juice and preserving its quality, supported by microbial, enzymatic, and sensory evaluations.

Prediction model of browning inhibitor concentration and its optimal composition for mass processing of ready-to-eat fresh-cut 'Fuji' apple (Malus domestica Borkh.) strains

In this study, we optimized the composition of the browning inhibitor for apples and established a prediction model for the browning inhibitor concentration in mass-processed fresh-cut apples based on electrical conductivity measurements. The "Fuji" apples that were harvested in Chungju, Korea, were used for this study. Vitamin C mixture (VCM) and trehalose (Tre) were used as browning inhibitors at a 4% ratio. The browning reaction under Δ3 of BI (browning index) for 5 days was defined as the target shelf-life of the apple flesh. The ΔBI of VCM and Tre was lower than that of VCM by 4%. It is revealed that the electrical conductivity of the browning inhibitor was highly correlated with its concentration and the number of soaked apples. Finally, the regression of the conductivity was fitted as Y = -0.0024 (number of soaked apples) + 0.5111 (R2 = 0.9931). In the validation test, the conductivity must be maintained at 0.4373 S/m or higher to maintain the target anti-browning level of Δ3 or less, which corresponded to ∼80% of the initial qualitative level after manufacture. The conductivity measurement of the browning inhibitor is suitable for monitoring and predicting its concentration in the mass processing of fresh-cut apple production due to the convenience of this method. PRACTICAL APPLICATION: The conductivity measurement of browning inhibitors can be applied not only to the mass processing of apple production but also to the anti-browning treatment of other fruits and vegetables, due to the convenience of this method. From these research results, it is expected to derive a formula that can predict the concentration of browning inhibitors through simple experiments for other fruits or vegetables.

Mixed fermentation and electrospray drying for the development of a novel stabilized wheat germ powder containing highly viable probiotic cultures

Nondairy fermented probiotic powder was developed based on stabilized wheat germ through mixed fermentation (Lactobacillus acidophilus and Lactobacillus plantarum) and electrospraying process. In the first step, the effect of mixed fermentation on lipase and lipoxygenase activity of wheat germ was investigated. The results showed a significant reduction in the activity of both enzymes (82.72% for lipase and 72% for lipoxygenase), therefore, mixed fermentation effectively stabilizes the wheat germ. In the next step, after the preparation of the solutions for drying process and investigating the physical properties (surface tension, electrical conductivity, and viscosity) of the solutions, the electrosprayability of the samples was evaluated at different conditions and revealed that 18 kV applying voltage, 0.3 flow rate, and 12 cm distance between tip to collector was the best for electrospraying the 20% solution of fermented wheat germ with morphologically most semi-uniform particles. Finally, the viability of the probiotics after drying process and during the storage at 25°C was examined. The number of initial cells counted as 14.48 ± 0.2 log cfu/g and the viability studies showed 0.55 log cfu/g decrease in the number of viable bacteria from initial count as a result of the electrospraying process. Furthermore, 7.86 ± 0.03 log cfu/g in freeze-dried and 9.05 ± 0.45 log cfu/g in electrosprayed samples survived after 70 days of storage.

Storage stability and shelf-life of soymilk obtained via repeated boiling and filtering: A predictive model

This study investigated the effects of different processing methods on the quality and nutrition of soymilk, as well as the changes in storage stability (centrifugal sedimentation rate (CSR), viscosity, and particle size) and shelf-life of soymilk at different storage temperatures (25°C, 35°C, 45°C, and 55°C). Results showed that soymilk processed via the repeated boiling-to-filtering method (RBFM) exhibited the highest protein content (3.89 g/100 g), carbohydrate content (1.27 g/100 g), and stability coefficient (0.950). The CSR and particle size of RBFM soymilk increased gradually during storage at different temperatures, while the viscosity and sensory score decreased. The correlation between the CSR and the sensory score of RBFM soymilk was the highest (R 2 = .9868). The CSR was selected as the key indicator to predict the shelf-life of RBFM soymilk. The average residual variation in RBFM soymilk shelf-life based on the predictive model was 10.78%, indicating the strong accuracy of the model for predicting the shelf-life of RBFM soymilk stored at temperatures ranging from 25-45°C. This study provides a theoretical basis and technological support for the development, transportation, and storage of soymilk and soymilk beverage products.

Glycation-mediated pea protein isolate-curcumin conjugates for uniform walnut oil dispersion: enhancing oxidative stability and shelf life

BACKGROUND

Traditional methods for fabricating protein-polyphenol conjugates have not preserved the structural and functional integrity essential for the food industry effectively. This research introduces an advanced encapsulation methodology designed to overcome these limitations, with the potential to enhance the stability of edible oil matrices significantly, leading to improved preservation techniques and extended shelf life.

RESULTS

Glycated pea protein isolate-curcumin conjugates (gPPI-CUR) were developed, demonstrating a marked improvement in the oxidative stability of walnut oil (WO), a proxy for edible oil matrices. Characterized by a Z-average diameter of 158.37 nm and an encapsulation efficiency of 80.94%, these conjugates demonstrated exceptional performance in reducing lipid oxidation and aldehyde formation. Molecular docking analysis confirmed the formation of robust bonds with curcumin, thereby amplifying antioxidant activity. The uniform distribution of gPPI-CUR throughout the walnut oil matrix, as validated by confocal microscopy, ensured sustained bioactivity and mitigated the risk of localized oxidation. Electron spin resonance spectroscopy corroborated the superior antioxidant properties of the conjugates, which translated into a substantial 19-day increase in the shelf-life of the oil.

CONCLUSION

The gPPI-CUR conjugates enhanced the oxidative stability of walnut oil significantly, as demonstrated by the increased shelf life and reduced lipid oxidation. This study introduced an effective encapsulation method that improved the stability and extended the shelf life of edible oils, aligning with consumer demands for high-nutrition food products. The results indicate that the gPPI-CUR conjugates could serve as a promising antioxidant strategy for food preservation, offering a practical approach to enhance food quality and safety. © 2025 Society of Chemical Industry.