Refrigerated Storage Conditions Research Articles

Odor-Cued Grab Air Sampling for Improved Investigative Odorant Prioritization Assessment of Transient Downwind Environmental Odor Events.

A critical prelude to any community odor assessment should be the prioritization of specific chemical odorants that are most responsible for targeted downwind odors. Unfortunately, and historically, this is a step that has often been bypassed or overlooked. However, correct understanding of the specific impactful volatile organic compounds (VOCs) can inform the follow-on sampling, analytical, and remediation strategies that are most appropriate and efficient, based upon the chemistry behind the issue. With this understanding, the techniques and sampling strategies presented herein should be viewed as a qualitative prelude rather than an addendum to a follow-up routine, automated downwind odor monitoring. Downwind odor characteristics can vary depending upon the size of the upwind source, interim topography, and wind conditions. At one extreme, the downwind odor plume from a relatively large source located on a flat open plain and under stable, near-straight line wind conditions can be rather broad, sustained, and predictable. In contrast, the plume from a small point source (e.g., a roof vent stack) located on irregular topography and under rapidly shifting wind conditions can be intermittent and fleeting ("spikes" or "bursts"). These transient odor events can be surprisingly intense and offensive, despite their fleeting occurrence and perception. This work reports on improving and optimizing an environmental sampling strategy for odorant prioritization from such transient downwind odor conditions. This optimization addresses the challenges of (1) sampling of transient odor "spikes" and (2) prioritizing odors/odorants from multiple, closely colocated point sources under transient event conditions. Prioritizing is defined as identifying the key impactful odorants downwind. Grab air sampling protocol refinement has emerged from actual community environmental odor assessment projects. The challenge of assessing transient odor events has been mitigated by utilizing (a) rapid, odor-cued whole-air grab sampling (i.e., activated by and synchronous with the perceived sensory spikes) into metalized fluorinated ethylene polymer (m-FEP) gas sampling bags; (b) immediate transfer from bags onto solid-phase microextraction (SPME) fibers or sorbent tubes; and (c) maintaining refrigerated storage and shipment conditions between field collection and in-laboratory analysis. Results demonstrated approximately 11-fold increases in target odorant yields for 900 mL air sample capture on sorbent tube transfers from 2 to 3 s "burst" odor event bag captures compared to equivalent direct collections (with sorbent tubes) at the same downwind receptor location but during perceived (stable) odor "lull" periods. An application targeting general odor sampling and point-source differentiation utilizing tracer gases is also presented.

Stabilization of the pharmaceutical finished dosages form by using various techniques

The stabilization of pharmaceuticals means that the drug product is physically, chemically and microbiologically stable at the recommended storage condition throughout the predefined shelf life of the product. Pharmaceutical formulations irrespective of its physical states have been used for their efficacy and safety so for as its therapeutic activity is concern. Stability of dosage forms is the ability of drugs to remains unaffected by environmental condition viz. temperature, humidity and microbiological contamination. This research work is an attempt to stabilize the drug product at controlled room temperature for the drug product which is stable at refrigerated storage condition. Hence the aim of present study was development and stabilization of the drug product at room temperature. Investigation of alternate manufacturing processes for stabilization of the drug product at controlled room temperature was one of the objectives of the work. Keywords: Stability, shelf life, lyophilization, freeze drying

Effect of oxidized starch on the storage stability of frozen raw noodles: Water distribution, protein structure, and quality attributes.

Freezing is a popular method of food preservation with multiple advantages. However, it may change the internal composition and quality of food. This study aimed to investigate the effect of modified starch on the storage stability of frozen raw noodles (FRNs) under refrigerated storage conditions. Oxidized starch (OS), a modified starch, is widely used in the food industry. In the present study, texture and cooking loss rate analyses showed that the hardness and chewiness of FRNs with added OS increased and the cooking loss rate decreased during the frozen storage process. Low-field nuclear magnetic resonance characterization confirmed that the water-holding capacity of FRNs with OS was enhanced. When 6% OS was added, the maximum freezable water content of FRNs was lower than the minimum freezable water content (51%) of FRNs without OS during freezing. Fourier-transform infrared spectroscopy showed that after the addition of OS, the secondary structures beneficial for structural maintenance were increased, forming a denser protein network and improving the microstructure of FRNs. In summary, the water state, protein structure, and quality characteristics of FRNs were improved by the addition of OS within an appropriate range.

Electrospun fiber mats based on chitosan-carrageenan containing Malva sylvestris anthocyanins: Physic-mechanical, thermal, and barrier properties along with application as intelligent food packaging materials

This study aimed to encapsulate Malva sylvestris extract (MSE) into chitosan-carrageenan (CH-KC) fibers using the electrospinning technique and monitor the freshness of silver carp fillets during the refrigerated storage conditions for 8 days. The CH-KC + MSE 4 % fiber mats were red at pH values lower than 3, purple at pH 4–6, dark blue at pH 7, green at pH 8–10, and brown at pH 11–12. The tensile strength, elongation at break, water vapor permeability, oxygen transmission rate, moisture content, and water solubility of fabricated fiber mats were 7.71–11.02 MPa, 13.12 %–30.00 %, 7.35–20.01 × 10−4 g mm/m2 h Pa, 3.81–8.23 cm3/m2 h, 15.74 %–27.34 %, and 3.90 %–7.56 %, respectively. Regarding the potential application of a fabricated indicator for freshness monitoring of silver carp fillets, total viable count, psychrotrophic bacterial count, pH, and total volatile basic nitrogen reached 8.91 log CFU/g, 8.03 log CFU/g, 8.10, and 40.18 mg N/100 g at the end of the study, respectively. Meanwhile, the CH-KC + MSE 4 % fiber mat color changed from white to green. These findings suggest that CH-KC + MSE 4 % fiber mats can be further utilized in the food industry to control the freshness of refrigerated silver carp fillets.

Optimizing the viability of microencapsulated Lactiplantibacillus plantarum using response surface methodology for dietary probiotic delivery

The study aimed to develop a microencapsulated probiotic (Lactiplantibacillus plantarum) delivery method, cryoprotected by chitosan-inulin complex microcapsules and freeze-dried to obtain maximum cell viability. Probiotic viability was assessed using simulated gastrointestinal conditions and storage at different temperatures. The L. plantarum microcapsules were developed using a Box-Behnken experimental design with varied concentrations of CaCl2, chitosan, and Inulin as an encapsulant agents. In addition, the current study used the response surface approach to explore the influence of various formulations and storage capsulate viabilities to verify an optimized L plantarum formulation. Under optimum conditions, small microbeads with the highest cell encapsulation efficiency were produced and the highest cell viability (68.33 %) was obtained. The results showed that the intelligent microcapsule of L. plantarum with SM significantly increased the viability of cells (p < 0.05) (approx. 108 log CFU/mL) and the release of the extract (85 %) in gastric simulation and intestinal simulation fluids, respectively when compared with free bacteria. In general, microencapsulated L. plantarum under previously optimized freeze-drying conditions showed promising efficiency that depends on cell viability during drying, gastrointestinal treatment, and refrigerated storage conditions and on the physicochemical properties of the powders.

Calcium impregnation during isochoric cold storage to improve postharvest preservation of fresh blueberries

Isochoric cold storage can be used to extend the shelf-life of fresh produce by delaying senescence through storage at subfreezing temperatures as well as hinder microbial growth with pressure. The effect of isochoric impregnation with CaCl2 on qualitative parameters of blueberries during isochoric cold storage at −2.5 °C and refrigerated storage at 5 °C for four weeks was investigated in this study. The results showed the synergistic effect of calcium impregnation and isochoric cold storage on the quality of blueberries. Isochoric impregnated blueberries better retained their weight, had better mechanical properties and had higher nutrient contents (anthocyanins, total phenolics and antioxidant capacity) than non-impregnated blueberries refrigerated at 5 °C. The benefits of isochoric impregnation with CaCl2 were greater for samples stored under isochoric conditions than under refrigerated conditions. However, the impregnated refrigerated samples still had better quality properties than non-impregnated refrigerated samples. Furthermore, panelists found no significant differences in preference for any of the sensory attributes between fresh blueberries and impregnated blueberries. Also, isochoric cold storage inhibited the growth of mesophilic aerobic bacteria, yeasts and molds under isochoric and refrigerated storage conditions. In conclusion, this study showed the possibility of using isochoric cold storage with calcium impregnation to develop ready-to-eat fresh blueberries with higher nutrient content and extended shelf-life.

Effects of collagen-based coating with chitosan and ε-polylysine on sensory, texture, and biochemical changes ofrefrigerated Nemipterus virgatus fillets.

In order to evaluate the effects of chitosan, ε-polylysine, and collagen on the preservation properties of refrigerated Nemipterus virgatus, samples were tested with different treatments for 10 days, namely chitosan, ε-polylysine and collagen (CH + ε-PL + CA), chitosan and ε-polylysine (CH + ε-PL), chitosan and collagen (CH + CA), ε-polylysine and collagen (ε-PL + CA), and the uncoated sample (CK). The results demonstrated that the bio-coating exhibited better preservation effects. The CH + ε-PL + CA, CH + ε-PL, CH + CA, ε-PL + CA treatments could significantly inhibit bacterial growth and retard the increase of total volatile base nitrogen (TVB-N), 2-thiobarbituric acid (TBA), K-value, and total viable counts (TVC) in N. virgatus fillets. The pH of all samples decreased and reached its lowest value on day 6, then increased significantly at the end of the experiment (p < .05). Water-holding capacity (WHC) of all the groups decreased continuously throughout storage, and CK reached 66.03% on day 6, which is significantly lower than CH + ε-PL + CA, CH + ε-PL, CH + CA, and ε-PL + CA (p < .05). On the contrary, the sensory scores of CH + ε-PL + CA, CH + ε-PL, CH + CA, and ε-PL + CA were significantly higher than the control, and the score of CH + ε-PL + CA (p < .05) was the best among all the groups. In terms of texture, CH + PL + CA also showed less cell shrinkage and tighter muscle fiber arrangement compared to other treatments. To sum up, the CH + PL + CA bio-coating proved to be a promising method for maintaining the storage quality of N. virgatus under refrigerated storage conditions.

Development of biomaterials based on chitosan-gelatin nanofibers encapsulated with Ziziphora clinopodioides essential oil and Heracleum persicum extract for extending the shelf-life of vacuum-cooked beef sausages

The aims of the current study were to encapsulate Ziziphora clinopodioides essential oil (ZEO, 0%, 0.15%, and 0.25%) and Heracleum persicum extract (HPE, 0%, 0.25%, and 0.5%) into the chitosan-gelatin (CH-GE) nanofibers through the electrospinning process to improve the shelf-life of vacuum-cooked beef sausages through 70 days of refrigerated storage. Scanning electron microscopy indicated that all nanofibers appeared thin, well-defined, smooth, and possessed uniform thread-like fibers without any beads or nodule formations. The Fourier transform infrared spectroscopy study confirmed the molecular interaction between encapsulated compounds and CH-GE nanofibers. The X-ray diffraction analysis of nanofibers showed an increase in crystallinity after incorporating ZEO and HPE into the polymer. Treated sausages with CH-GE-ZEO 0.25%-HPE 0.25% and CH-GE-ZEO 0.25%-HPE 0.5% showed significantly lower microbial population and lipid oxidation than the control group during the experiment period (P < 0.05). Sausages formulated with designated CH-GE nanofibers had better microbial, chemical, and sensory properties compared to sausages treated with pure ZEO/HPE during refrigerated storage. The findings also showed that treated sausages with CH-GE-ZEO 0.25%-HPE 0.5% had the highest color, odor, texture, and overall acceptability after 70 days of refrigerated storage conditions. Therefore, this treatment could be applicable for the prolonged storage conditions during cooked beef sausage production.

First Report of Cladosporium ramotenellum Causing Sooty Spot on Postharvest Clementines in the United States.

In 2022, post-harvest symptoms of black spots were observed at an incidence of 2-5% on easy peeling clementines (citrus × clementina) in a fresh fruit market in Phoenix metropolitan area, Arizona. Black lesions on the fruit rind were superficial, circular, dry, and firm with gray sporulation. Gray or black aerial mycelium was also noticed on top of the black spots. Black spots were distributed over the entire fruit surface without any regular patterns. Maceration of rind and flesh was also noticed under refrigerated storage conditions. Two isolates were obtained (S13 and S14) and cultured on potato dextrose agar (PDA) at 25oC for 14 days. The colony color and texture of both isolates were identical on PDA: olivaceous black with abundant sporulation, margin entire edge to slightly undulate. Conidia were 0-1 septate and globose or ellipsoid with sizes ranging from 4-10 × 2-4 μm (n = 15). Ramoconida were also 0-1 septate and ellipsoid to cylindrical with sizes ranging from 15-30 × 2-5 μm (n = 15). Conidiophore had a width of 3-6 μm (n = 15). Isolates were identified as Cladosporium ramotenellum based on these morphological features (Bensch et al. 2012). The IDs of these two isolates were further confirmed by genomic DNA isolation, PCR amplification and sequencing of the ITS1-5S-ITS2-28S region of rDNA (V9G/LR5 de Hoog and Gerrits van den 1998, primers ITS4/ITS5 White et al.), actin gene (ACT-512F/ACT-783R, Carbone and Kohn 1999), and elongation factor 1α gene (EF1-1018F/EF1-1620R, Stielow 2015). Sequences of the two isolates were identical and thus only one sequence of each gene was deposited in the GenBank. A BLASTn search of actin sequence (233-bp, OQ185511) revealed 99.1% match with ex-type sequence EF 679538 (strain CBS:121628) of C. ramotenellum holotype (query coverage: 97%). BLASTn analysis of a portion of EF-1α gene (579-bp, OQ185512) revealed more than 99.7% similarity with sequences KU933429 (ATCC strain 16022) and MT881827 (strain 18EPLE003) of C. ramotenellum (query coverage: 100%). The ITS sequence (1519-bp, OQ236707) was identical to the ITS sequences of C. ramotenellum strains in easy peeler mandarins from Peru (Murciano et al. 2021). Pathogenicity tests were carried out twice on fresh easy-peeling clementine fruit. The inocula (1 x 105 spores/ml) were prepared in sterile distilled water containing 0.1% Tween 20 (TW) by mixing the conidial suspensions of two isolates from 7-day-old PDA cultures. Ten fruit were washed, surface sanitized with 70% ethanol, and wound-inoculated by immersing five fruit in spore suspension for 1 min. Five control fruit were wound-inoculated with TW. Inoculated and control fruit were stored in separate zip-lock bags for one week. Black spots resembling those observed on naturally infected fruit were present on inoculated fruit, while control fruit remained symptomless. C. ramotenellum was reisolated and was morphologically identical to the original isolates, thus completing Koch's postulates. C. ramotenellum has been reported as a fungal pathogen causing sooty spots on easy peeler mandarins from Peru (Murciano et al. 2021). To our knowledge, this is the first report of C. ramotenellum causing postharvest sooty spot and decay on clementines in the United States. Results show that infected fruit is potentially a pathogen source for long-distance dispersal. This occurrence was communicated to the state regulatory agencies for regulatory actions on imports of citrus fruit from countries with the occurrence of C. ramotenellum.

Influence of low temperature hydrodynamic cavitation treatment on shelf life of ascorbic acid‐treated sugarcane juice

AbstractSugarcane juice has a lower shelf life owing to enzymatic browning as well as microbial activity. To overcome these issues, fresh sugarcane juice was treated with ascorbic acid, a strong antioxidant, and further subjected to low‐temperature hydrodynamic cavitation (LTHC) treatment at 4°C/.35 MPa for 30 min. The AALHC‐treated juice was filled into PET bottles and stored under atmospheric (25 ± 5°C) and refrigerated (4 ± 1°C) conditions. The changes in reducing sugar, total sugar, color (ΔE), microbial load, total phenolic content, total flavonoid content, and antioxidant activity of sugarcane juice during the storage period were evaluated. During the storage, better retention of the quality parameters was observed in the AALTHC processed sugarcane juice followed by AA‐treated sugarcane juice and fresh sugarcane juice. Under the atmospheric storage, fresh juice and AA‐treated juice were spoiled within a day, whereas the AALTHC‐treated sugarcane juice could last for 4 days. On the other hand, under the refrigerated storage conditions (4 ± 1°C), the quality of the fresh and AA‐treated sugarcane juice could last only for a week, while the quality of AALTHC could be maintained up to 42 days.Practical ApplicationsThe current study aims to improve the shelf life of sugarcane juice by low‐temperature orifice‐based hydrodynamic cavitation. Sugarcane juice has a short shelf life owing to high levels of microbiological contamination and enzymatic reactions that begin immediately following extraction. The use of hydrodynamic cavitation technique enables a significant reduction in microbial load as well as spoilage enzymes, with minimum effect on the nutrient profile and sensory qualities. The treatments presented in this study are successful, inexpensive, more practicable, and long‐term enough to be scaled up for larger‐scale production of sugar cane juice. The outcomes of this study may be useful for developing a fortified beverage industry employing low‐temperature hydrodynamic cavitation.

Nanoparticles Titanium Dioxide with Thymus vulgaris extract in preservation and prolong the shelf life of cheese

Cheese is considered a perishable food that is affected by microorganisms, and due to the properties of nanomaterials that have antimicrobial activity, they have been used synergistically with plant extracts in inhibiting the action of microorganisms that cause cheese spoilage. In this study, TiO2 (Titanium dioxide) nanoparticles were synthesized using Thymus vulgaris leaves extract (TVLE) . Atomic Force Microscopywas used to investigate Titanium dioxide/ TVLE nanoparticles characterize, which improved the regular spherical shape and granular distribution of nanoparticles with a particle size of 13 nm . The results showed that the minimum inhibitory concentration (MIC) of Titanium dioxide was at a concentration of 4 mg/ml and 80 mg/ml for TVLE, while it was 2 + 20 mg /ml for Titanium dioxide and TVLE .The inhibitory effect increased against Brucella melitensis recorded 12 mm when mixing Titanium dioxide and TVLE, compared with the inhibitory effect of Titanium dioxide, which recorded 10.5 mm and TVLE, with an inhibition diameter 8.1 mm. The effect of using titanium particles and thyme leaves’ extract was studied alone at a concentration of 4 mg/ml and 80 mg/ml and also when mixed in the microbial properties and pH of white soft cheese samples, which were prepared in the laboratory and contaminated with Brucella melitensis at refrigerated storage conditions (5Cº) for 21days. The effect of the synergism relationship between TiO2 / TVLE significantly reduced the total number of microorganisms in samples contaminated and uncontaminated with B. melitensis. Adding titanium dioxide and TVLE at concentrations of 4 and 80 mg/ml contributed significantly to maintaining the pH level during the storage period compared with the control group.

Study on stability of antioxidant activity of fresh, pasteurized, and commercial fruit juice during refrigerated storage

Fruit juice is growing in popularity worldwide due to its excellent wellness properties, and most people usually like to store the juice in the refrigerator to drink it later. The current study was undertaken to compare the stability of antioxidant activity of selected samples (apple, orange, and pineapple) of juice that were fresh (untreated), pasteurized at 70 °C for 30 min, and commercially available in Bangladesh at 4 °C in refrigerated storage conditions for up to 21 days. The fresh juice was prepared by crushing and pressing the fruits using an electric mixer, and the pasteurized juice was prepared by running the fruits through a pasteurization procedure at 70 °C for 30 min in a water bath. The total phenolic content (TPC), total flavonoid content (TFC), total antioxidant activity (TAA), beta-carotene content, and vitamin C content throughout 21 days of refrigerated storage were studied by using standard methods. The study found that TPC and TFC of the fresh juices (apple, orange, and pineapple) were statistically significant (p < 0.05) on 0 and 7 days, whereas pasteurized and commercial juices were statistically significant (p < 0.05) on 0, 7, and 14 days. As for TAA, orange and pineapple juices, except fresh pineapple juice, were statistically significant (p < 0.05) up to 21 days. In the case of beta-carotene content, only fresh and pasteurized orange juices were statistically significant (p < 0.05) on 14 days. Apart from apple, all the juice samples had vitamin C content up to 21 days, and these results were statistically significant (p < 0.05) at 0, 7, 14, and 21 days. In addition, most of the samples showed drastic degradation after 7 days for both bioactive compounds and antioxidant activity. It is concluded that the stored fruit juice at 4 °C in refrigerated storage conditions should be consumed within 7 days to get the desired properties of the juice.

Enhancing the Shelf Life of Palak and Coriander through Modified Atmosphere Packaging under Diverse Storage Environments

Aim: Green leafy vegetables are renowned for their rich vitamin and mineral content as well as their nutritional value. However, these vegetables are highly perishable due to their accelerated rates of respiration and transpiration. The process of packing and the choice of packaging materials play a crucial role in extending their shelf life. The main aim of this study was to prolong the shelf life of two prominent leafy greens, Palak (Beta vulgaris L. var. bengalensis) and Coriander (Coriandrum sativum L.), using Modified Atmospheric Packaging (MAP) and various packaging materials. Study Design: The study employed an FCRD experimental design with 12 treatments and 3 replications. Place and Duration of Study: This study was conducted at Department of Vegetable Science, HC&amp;RI, TNAU, Coimbatore during the year 2023. Methodology: Freshly harvested Palak and Coriander were collected, sorted, and prepared as 250-gram samples. Two packaging materials (LDPE and PP) and three gas compositions (G1, G2, G3) was employed. The vegetables were stored under both ambient (35±5°C) and refrigerated (5°C) conditions and their physiological loss in weight (PLW %) was monitored. The observations were taken every day up to the spoilage of the produce. Results: According to the research findings, vegetables could remain fresh under ambient storage for up to 4 days and under refrigeration for up to 15 days. In ambient storage conditions, Palak exhibited the longest shelf life in treatment T3 - G3M1 (4% O2, 5% CO2, LDPE), followed by T5 - G2M2 (6% O2, 5% CO2, PP). Meanwhile, Coriander showed better shelf life in treatment T2 - G2M1 (6% O2, 5% CO2, LDPE), followed by T6 - G3M2 (4% O2, 5% CO2, PP). Under refrigerated storage conditions, Palak exhibited an extended shelf life in treatment T9 - G3M1 (4% O2, 5% CO2, LDPE), followed by T12 - G3M2 (4% O2, 5% CO2, PP). For Coriander, the best results were achieved with treatment T12 - G3M2 (4% O2, 5% CO2, PP), followed by T8 - G2M1 (6% O2, 5% CO2, LDPE). Conclusion: Proper packaging and gas composition significantly increased the shelf life of these leafy greens, offering potential benefits for both producers and consumers. Palak had a longer shelf life when stored under refrigerated conditions, up to 14 days, while Coriander could be kept fresh for up to 12 days in the refrigerator. Gas composition G3 (4% O2, 5% CO2) was found to be effective and LDPE was generally the preferred packaging material in extending the shelf life of the vegetables.

The Visibility of Changes in the Antioxidant Compound Profiles of Strawberry and Raspberry Fruits Subjected to Different Storage Conditions Using ATR-FTIR and Chemometrics.

Strawberry cultivars Portola and Enduro, as well as raspberry cultivars Enrosadira and Kwazi, were evaluated for their antioxidant potential after treatment with gaseous ozone and different refrigeration storage conditions. Their antioxidant capacity was investigated with ABTS and DPPH methods, and the chemical composition was determined by measuring the total phenolic (TPC) and flavonoid (TFC) compounds. The classification of different samples of berry puree was influenced significantly by both the cultivars and the refrigeration storage method. Moreover, FTIR spectroscopy coupled with chemometrics was used as an alternative technique to conventional methods to determine the chemical composition of strawberries and raspberries. The chemometric discrimination of samples was achieved using principal component analysis (PCA), hierarchical clustering analysis (HCA) and linear discriminant analysis (LDA) modelling procedures performed on the FTIR preprocessed spectral data for the fingerprint region (1800-500 cm-1). The fingerprint range between 1500 and 500 cm-1, corresponding to deformation vibrations from polysaccharides, pectin and organic acid content, had a significant impact on the grouping of samples. The results obtained by PCA-LDA scores revealed a clear separation between four classes of samples and demonstrated a high overall classification rate of 97.5% in differentiating between the raspberry and strawberry cultivars.

Intelligent double-layer polymers based on carboxymethyl cellulose-cellulose nanocrystals film and poly(lactic acid)-Viola odorata petal anthocyanins nanofibers to monitor food freshness

The present study was conducted with the aim of fabricating smart bilayer polymers based on carboxymethyl cellulose-cellulose nanocrystals film and poly(lactic acid)-Viola odorata extract nanofibers (CMC-CNC and PLA-VOE) for freshness monitoring of Pacific white shrimps, minced lamb meat, chicken fillets, and rainbow trout fillets, during refrigerated storage conditions. The fabricated indicators based on CMC-PLA-VOE 5%, CMC-CNC 1%-PLA-VOE 5%, and CMC-CNC 3%-PLA-VOE 5% presented remarkable color changes in pH 1–12 buffer solutions, including red at pH 1–6, violet at pH 7–8, green at pH 9–10, and brown at pH 11–12. Significantly lower water vapor permeability and oxygen transmission rate of prepared polymers were found in comparison with the control groups (P < 0.05). Regarding the monitoring of food samples in real-time, the samples spoiled after 3 days, evidenced by total viable count, psychrotrophic bacterial count, total volatile basic nitrogen, and pH values of 7.17–7.54 log CFU/g, 5.68–6.23 log CFU/g, 25.14–28.12 mg N/100 g, and 7.10–7.66, respectively. Meanwhile, the noticeable color change of prepared indicators from white to violet (day 3) and finally dark violet (day 7) was observed, indicating a potential application in intelligent packaging for real-time control of the freshness of perishable food samples.

The Inhibitory Effect of Sodium Bicarbonate, Phylex and Seaweed Extract Against Penicillium digitatum Causing Green Rot Disease in Local Lemon Fruits

This study was conducted in the College of Agricultural Engineering Sciences/University of Baghdad during the years 2021 and 2022. The study aimed to evaluate the biological activity of Sodium bicarbonate, Phylex and the Seaweed extract in controlling the green mold infection in the local lemon at refrigerated storage conditions (4°C). Two isolates of Penicillium digitatum were identified on Potato Dextrose Agar (PDA) and coded as L1 and L2. The results of this study confirmed the high pathogenicity of P. digitatum isolates to lemon fruits. The symptoms of green rot infection appeared on the fruits after 4 days of pathogen inoculation. The preservative and anti-fungal activity of Sodium bicarbonate, Phylex and Seaweed extract were assessed using local lemon fruits under refrigerated-storage conditions. The highest inhibitory effect was reported when 64 g/L Sodium bicarbonate, 4ml/L Phylex and 128 g/L Seaweed extract were used, preventing 100% of P. digitatum colonies growth after 6 days of treatment at 25±2°C. The data of the refrigerated-storage experiments showed that the Phylex treatment of artificial-wound fruits inoculated with the pathogen was more efficient than Sodium bicarbonate in protecting the lemon fruits from green mold infection. Phylex treatment protected the fruits from the fungal infection for 45 days storage, compared to the Sodium bicarbonate treatment, with which, the fruit infection appeared after 30 days of refrigerated-storage (at 4°C).

Sprout-suppressing 1,4-dimethylnaphthalene treatment reduces dry rot infection in potato tubers during postharvest storage

Postharvest losses related to dry rot can reach 60% during long-term storage of potato tubers. Current control methods do not provide an efficient solution to control dry rot, and inducing resistance through elicitors may be a promising way to manage this disease. In this study, we evaluated the ability of 1,4-dimethylnaphthalene (1,4-DMN) and methyl jasmonate (MeJa) to induce resistance to dry rot caused by Fusarium nirenbergiae, using ‘Asterix’ and ‘Challenger’ under refrigerated storage conditions. In vitro and in vivo tests were performed evaluating the volume of infection and the activity of antioxidant and defense enzymes, including polyphenol oxidase, peroxidase, catalase, ascorbate peroxidase, phenylalanine ammonia lyase, lipoxygenase and β-1,3 glucanase. The results reinforce the difference in susceptibility to dry rot between the genotypes, with the ‘Asterix’ and ‘Challenger’ being classified as resistant and susceptible, respectively. The in vivo tests corroborated the findings of the in vitro tests, demonstrating that only 1,4-DMN retarded the growth of F. nirenbergiae. Throughout the progression of the disease, the activity of the defense enzymes revealed a more consistent response regarding the difference in susceptibility between cultivars than in response to the applied elicitors. Therefore, our data suggest that the efficiency of 1,4-DMN in reducing the volume of infection is linked to its direct action on the pathogen and not to the activation of a defense switch via antioxidants and defense-related enzymes. Unlike 1,4-DMN, MeJa did not control potato dry rot.

Effect of Oxalic Acid on Control of Post-harvest Browning of Litchi (Litchi chinensis L.)

Post-harvest browning of litchi is a common phenomenon that occurs due to enzymatic and non-enzymatic reactions. Enzymatic browning is primarily caused by polyphenol oxidase (PPO) activity, leading to the formation of brown pigments. Non-enzymatic browning is caused by the Maillard reaction between reducing sugars and amino acids. Factors such as temperature, humidity, and mechanical damage can accelerate browning. Proper handling, storage, and the use of antioxidants can help minimize post-harvest browning, extending the shelf life and maintaining the visual appeal of litchi fruits. The present investigation was laid out in the post-harvest laboratory of horticulture department, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj during the year 2022-2023. The experiment was laid out in the CRBD with 8 treatments and 3 replications. Litchi fruit, Cv. Purvi (about 80%- matured stage), were harvest from a Local market Prayagraj, fruit was selected for uniformity of size and colour, and blemished and diseased fruit were discarded. The selected fruit were dipped in different oxalic acid concentration solution (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0mM) and Bavistin (0.05mg) as the control) for 10 mint 4 h of harvest, and then air dried. Each 10 fruit of the treated fruit was packed into a plastic punnet and wrapped with a 0.2-mm polyethylene bag, and then stored in an ambient condition. Post-harvest storage studies revealed that under ambient and refrigerated storage conditions T8 Oxalic acid (4.0mM) + Bavistin (0.05%) treatment showed slower rate of reduction on fruit length (cm) and fruit weight (g), browning (%) were significantly affected by treatments. There was significant effect of treatments on chemical parameters like pH, TSS (0Brix), acidity (%), ascorbic acid (mg100g), reducing sugar under ambient and refrigerated storage at different day’s intervals.

Temperature-Dependent Storage Stability and Shelf-Life Assessment Of Palmyra Blended Beverage

Nutraceuticals added ready to serve blended beverages was prepared from tender palmyra pulp and the storage study of the developed beverages was carried out in this research. Blended beverage was prepared by blending the tender palmyra pulp along with green chilly pulp and ginger extract. For each treatment the final TSS was adjusted to 12 °Brix (as per optimization) in the blended juice. After the finalization of the juice blend, the pasteurized juice was further packed with preservatives such as potassium meta-bisulphite and sodium benzoate at 300ppm. The Palmyra blended juice was stored under ambient (30±5 °C) and refrigerated condition (4±1 °C) in glass bottles. The effect of preservative treatment and storage condition on quality parameters during storage of PBJ was investigated for a period of 180 days. The quality parameters considered under study were biochemical, phytochemical, sensory and microbiological property. The palmyra blended juice with sodium benzoate performed best under both ambient and refrigerated storage conditions up to 90 and 180 days respectively.

Characterization of ultrasonicated assisted encapsulated omega 3 fatty acids and inulin for food applications

The paper deals with development of emulsion with special features such as omega-3 fatty acids derived from plant sources and inulin as a core material employing whey protein concentrate, & maltodextrin as wall material as a medium of fortificant. Amongst different combinations of tested amplitude and time of ultrasonication, optimized emulsion exhibited no signs of oil separation until 60 days, when kept under ambient and refrigerated storage conditions. Parameters such as particle size (nm), polydispersity index, zeta potential, and viscosity were helpful to form stable emulsion by means of ultrasonic processor. The optimized emulsion contained Dietary fibre content (7.40%); Alpha linolenic acid, (5.35%); Eicosapentaenoic acid (0.56%) and Docosahexaenoic acid (0.75%). To improve the shelf life, the shelf-stable emulsion was subjected to spray drying process to obtain encapsulated powder by optimizing the inlet and outlet temperature as 160 °C and 80 °C, respectively, for the retention of nutraceuticals. Powder demonstrated the presence of Alpha Linolenic Acid (ALA), Eicosapentaenoic acid (EPA), and Docosahexaenoic acid (DHA) @17.8, 1.82, & 1.95% respectively with 95.61% encapsulation efficiency. Bioavailability studies subjected to mimic human gastric and intestinal conditions, paved the way to further food applications which may confer health benefits in the human systems.