Commercial Storage Conditions Research Articles

Efficacy of the entomopathogenic fungus, Metarhizium anisoplae, against Khapra beetle Trogoderma granarium (Coleoptera: Dermestidae) under laboratory conditions

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is an important pest of stored wheat worldwide. This study assessed the efficacy of two isolates of M. anisoplae (commercial and local isolates). Different conidial concentrations (1×108, 1×106, 1×104) conidia/ml-1 and fungal filtrate (100, 75, 50) % of M. anisoplae were evaluated. In both fungal isolates, corrected mortality of T. granarium after exposure varied according to fungal concentrations conidial concentration of conidia/ml-1, and the fungal filtrate at a concentration of 75% caused the highest mortality rates. In addition, mortality rates were significantly varied according to the beetle's developmental stage. Both isolates of M. anisoplae caused between 41 and 67.6 % reduction in total fecundity of the female adults. The results demonstrate no significant differences between the local isolate of M. anisoplae and commercial formulation (Met 52 EC). Further studies under commercial storage conditions are required. Keywords: Insects storage pests, biological control, Entomopathogenic fungi

Survival of Listeria monocytogenes and Salmonella in citrus storage waxes or on lemons held under common commercial storage conditions

To prolong cold storage, diluted storage waxes are applied to washed lemons after harvest and before packing, without drying steps, to reduce premature rotting and water loss. The survival of Listeria monocytogenes and Salmonella in undiluted and diluted storage waxes (S1–S4), and on lemon surfaces under common commercial storage were investigated. Populations of L. monocytogenes declined more slowly than Salmonella in undiluted storage waxes over 24 h of storage at 4 or 22 °C. L. monocytogenes (inoculated at ∼6 log CFU/mL) was detected by enrichment in undiluted waxes S2, S3, and S4 after 75–135 days at 4 °C but not after 30, 10, or 105 days, respectively at 22 °C. L. monocytogenes survived better in diluted than in undiluted storage waxes at 22 °C. Populations of L. monocytogenes (∼6 log CFU/lemon) declined by 0.64–1.62 log on lemon surfaces right after waxing. Populations of L. monocytogenes decreased to <1.30 log CFU/lemon after 28 days (1:9 S1) or 75 days (other treatments) at 12 °C and ≥93% RH. Except for 1:9 S1, L. monocytogenes was detected by enrichment in all lemon samples over 87 days of storage. Packinghouses should consider the survival of L. monocytogenes and Salmonella in citrus storage waxes in their food safety programs.

Improved Phenolic Profile, Sensory Acceptability, and Storage Stability of Strawberry Decoction Beverages Added with Blueberry Decoctions

Blueberries are rich in polyphenols, anthocyanins, and proanthocyanidins; however, they are expensive. In contrast, strawberries have a lower cost and are rich in ellagitannins. Therefore, a strawberry-blueberry blend decoction could produce a low-cost beverage with a rich and diverse phytochemical profile. In this study, we developed three berry-based beverages: blend strawberry-blueberry (SBB), strawberry (SB), and blueberry (BB). The polyphenol profile of the beverages was characterized by UPLC-ESI-Q-ToF MSE, an acceptability test was carried out with potential consumers, and a stability analysis was performed under commercial storage conditions (4, 25, and 34 °C). The SBB exhibited a good sensorial preference (score of 81.3) and showed high contents and a diverse composition of anthocyanins and proanthocyanidins, which were up to 3.0- and 1.2-fold higher compared to the SB, respectively. Regarding the storage stability, the SBB showed better retention of lightness (97.9%) and red color (66.7%) at the end of the storage under refrigerated conditions (4 °C) compared to the SB. Therefore, these results demonstrate that using blended berry fruits leads to the creation of a functional beverage that has higher nutraceutical potential than single-berry-based beverages.

Effect of Chitosan-24-Epibrassinolide Composite Coating on the Quality Attributes of Late-Harvested Pomegranate Fruit under Simulated Commercial Storage Conditions.

This study evaluated the efficacy of chitosan (CH) functionalized with 24-epibrassinolide (EBR) coating in terms of preserving the postharvest quality of late-harvested pomegranate (cv. Wonderful) fruit. Late-harvested pomegranate fruit were immersed for 3 min in different surface treatment solutions—CH 1.5% (w/v), CH + 2 µM EBR, CH + 5 µM EBR, CH + 10 µM EBR and CH + 15 µM EBR—and distilled water was used as a control treatment. The fruit were air-dried and subjected to long storage duration at 5 °C with 85 ± 5 RH for 12 weeks. At 4-week sampling intervals, a batch of fruits was placed at 21 ± 2 °C and 65–70% RH for a further 3 d period to simulate retail conditions before measurements were taken. Fruit physiological responses, physico-chemical properties, phytochemical contents, antioxidant capacity and physiological disorders were monitored during storage. The results showed that the CH-EBR composite edible coatings significantly (p < 0.05) delayed degradative processes due to senescence. The CH-EBR treatments delayed colour, texture and total soluble solids (TSS) degradation and reduced weight loss, respiration, electrolyte leakage and spoilage compared to the control and CH treatment. The treatment effect was more noticeable on fruit treated with CH + 10 µM EBR, which exhibited lower weight loss (18.19%), respiration rate (7.72 mL CO2 kg−1 h−1), electrolyte leakage (27.54%) and decay (12.5%), and maintained higher texture (10.8 N) and TSS (17.67 °Brix) compared to the untreated fruit with respective values of 24.32%, 18.06 mL CO2 kg−1 h−1, 43.15%, 37.5%, 8.32 N and 17.03 °Brix. This was largely attributed to the significantly higher antioxidant content, including the ascorbic acid content, total phenol content, total anthocyanin content and DPPH (radical scavenging activity), of the coated fruit compared to the control fruit. Therefore, CH + 10 µM EBR treatment is recommended as a postharvest management strategy to improve the quality preservation of late-harvested pomegranate fruit during storage.

Effect of chitosan and silicon oxide treatments on postharvest Valencia Late (Citrus × sinensis) fruits

The efficacy of chitosan and silicon oxide to prevent postharvest weight loss and fungi infection in 'Valencia Late' oranges was tested. Three silicon oxide concentrations (0.1%, 0.2%, 1%) were applied as preharvest treatments. Chitosan treatments were performed at the same concentrations in postharvest fruit. Preharvest applications were carried out by tractor spraying, while fruit were submerged for 30 seconds in baths with the chitosan concentrations in the postharvest applications. In both cases, a positive control (water treatment) and negative control (fungicide) were included. Treated fruit were stored in a chamber to simulate commercial storage conditions (4 ºC, 90% RH) for 9 weeks. After this time, the weight loss and damage caused by fungi due to natural infection were evaluated. Both silicon oxide and chitosan applications were effective in controlling natural infection by Penicillium species but had no positive effect on weight loss.

Optimizing Walnut Storage Conditions: Effects of Relative Humidity, Temperature, and Shelling on Quality after Storage

With increasing walnut production in California, walnuts are stored for longer times. It is increasingly important to optimize storage conditions, wherever possible, to reduce quality degradation. We examined the effects of temperature (5, 15, and 25 °C) and relative humidity (20%, 40%, and 60% in year 1 and 40%, 60%, and 80% in year 2) on the rate of quality degradation of four walnut varieties. The relationship between water activity and moisture content was investigated for each variety. In addition, the effects of harvest timing (early vs. late) and storage as shelled or in-shell product were investigated. Later harvested walnuts had darker kernel color (P &lt; 0.001), and walnuts stored as kernels (shelled) had higher rates of peroxide formation and free fatty acid development than walnuts stored in-shell. Temperature had a significant effect on quality with faster degradation at higher temperatures. There was a significant interaction between temperature and relative humidity effects on quality. The effects of relative humidity were often not significant at storage temperatures of 5 °C but were apparent at 15 °C and at 25 °C. Managing relative humidity during walnut storage is difficult under typical commercial storage conditions; however, when low temperature storage is used, quality is preserved even when relative humidity is not controlled, although storage at 80% relative humidity should be avoided. To reduce the rate of color darkening and rancidity development during commercial storage, operators should emphasize storage at lower temperatures, at least below 15 °C.

Evaluation of Oxidative Stability of Full Fat Soybean Flour in Storage and Sensory Quality of Tuo Zaafi-Enriched with Soy Flour as Influenced by Traditional Processing Methods

The oxidative stability of pretreated full-fat soybean flour (FFSF) was evaluated under commercial (Experiment I) and accelerated conditions (Experiment II). In Experiment I, soybeans were pretreated using germination, soaking (24 h), or roasting (110–120 °C), and the dried, milled FFSF was stored for 120 days under commercial storage conditions in two cities in Ghana. Acid value (AV) and peroxide value (PV) were determined. The proximate and sensory quality of Tuo Zaafi, a maize-only dish in northern Ghana enriched with 10–30% of the pretreated FFSF, was assessed. Before storage, all samples had similar PV (1.907–4.305 mEq/kg oil); however, the AV of the germinated sample was higher than that of the unprocessed samples (10.83 vs. 3.13 mgKOH/g oil; p < 0.001). After storage, although AV fluctuated, the PV was similar (2.39–3.74 mEq/kg oil; p = 1.00). Storage location showed no significant differences in terms of AV (4.96–4.97 mgKOH/g oil; p = 0.994), unlike PV (2.07–3.55 mEq/kg oil; p < 0.001). Increasing the levels of the pretreated FFSF in Tuo Zaafi resulted in lower consumer preference scores for all sensory attributes. In Experiment II, FFSF samples (dehulled and nondehulled) prepared from germination, soaking (18 h and 24 h) and roasting were evaluated under accelerated conditions (AC) of controlled temperature (45 ± 0.1 °C) and relative humidity (81 ± 1%) for AV, PV, p-anisidine value (pAV), lipoxygenase activity (LOX), color, and moisture. Pretreatment, condition, time, and their interaction affected the oxidative stability of all FFSF samples (p < 0.001). Roasted samples showed the highest increase in AV and pAV in both storage conditions (p < 0.05). Under room temperature conditions (RTC), the roasted and germinated samples had lower LOX activity (p < 0.05) at the end of storage time compared to that of the controls. In conclusion, germination and soaking reduced oxidation of FFSF, while roasting promotes it, despite its common use.

Fate of Salmonella Typhimurium and Listeria monocytogenes on Whole Papaya during Storage and Antimicrobial Efficiency of Aqueous Chlorine Dioxide Generated with HCl, Malic Acid or Lactic Acid on Whole Papaya.

Papaya-associated foodborne illness outbreaks have been frequently reported worldwide. The goal of this study was to evaluate the behavior of Salmonella Typhimurium and Listeria monocytogenes on whole papaya during storage and sanitizing process. Fresh green papayas were inoculated with approximately 7 log CFU of S. Typhimurium and L. monocytogenes and stored at 21 or 7 °C for 14 days. Bacteria counts were determined on day 0, 1, 7, 10 and 14. Fresh green papayas inoculated with approximately 8 log CFU of the bacteria were treated for 5 min with 2.5, 5 and 10 ppm aqueous chlorine dioxide (ClO2). The ClO2 solutions were generated by mixing sodium chlorite with an acid, which was HCl, lactic acid or malic acid. The detection limit of the enumeration method was 2.40 log CFU per papaya. At the end of storage period, S. Typhimurium and L. monocytogenes grew by 1.88 and 1.24 log CFU on papayas at 21 °C, respectively. Both bacteria maintained their initial population at inoculation on papayas stored at 7 °C. Higher concentrations of ClO2 reduced more bacteria on papaya. 10 ppm ClO2, regardless the acid used to generate the solutions, inactivated S. Typhimurium to undetectable level on papaya. 10 ppm ClO2 generated with HCl, lactic acid and malic acid reduced L. monocytogenes by 4.40, 6.54 and 8.04 log CFU on papaya, respectively. Overall, ClO2 generated with malic acid showed significantly higher bacterial reduction than ClO2 generated with HCl or lactic acid. These results indicate there is a risk of survival and growth for S. Typhimurium and L. monocytogenes on papaya at commercial storage conditions. Aqueous ClO2 generated with malic acid shows effectiveness in inactivating the pathogenic bacteria on papaya.

Efficacy of Clonostachys rosea, as a promising entomopathogenic fungus, against coleopteran stored product insect pests under laboratory conditions

BackgroundEfficacy of new isolates of the entomopathogenic fungus (EPF), Clonostachys rosea, against adult stage of the most serious coleopteran stored product insect pests in Iraq, Trogoderma granarium Everts (Coleoptera: Dermestidae), Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) and Callosobruchus maculatus Fabricius (Coleoptera: Chrysomelidae), was evaluated under laboratory conditions. Two isolates of C. rosea, associated with the green peach aphid (Myzus persicae Sulz.), were isolated and investigated. Efficacy of C. rosea isolates was evaluated by two concentrations (1 × 108 and 1 × 106 conidia ml−1).ResultsCorrected mortality rates caused by both C. rosea isolates, 6 days post-treatment, with 1 × 108 conidia ml−1, ranged from 70.7 to 75.7%. Fungal infection caused 37–53% reduction in total fecundity of the adult females of the three tested insect species, 6 days post-treatment.ConclusionObtained results demonstrated that C. rosea isolates had potentials as a biological control agent against coleopteran stored product insect pests. However, further studies under commercial storage conditions are required.

Geographical indication (GI) branded quality: a study case on the homogeneity of the Carota Novella di Ispica Region

Quality criteria for fresh produce are often underestimated in the industry, as the majority of parameters regulated are visual. Consequentially, this negatively affects the physicochemical, nutraceutical and organoleptic properties of the end product offered to the consumer. To deal with this, more information is required about the pre- and postharvest development of quality-related parameters. The aim of this work was to evaluate the postharvest quality of four different carrot cultivars of the Carota Novella di Ispica brand. The brand is protected by geographical indication and is well known around Italy for its high quality. Carrots were exposed to standard commercial storage conditions for 6 weeks. Samples were collected at the beginning, after 3 weeks and at the end of the period. At each time point, physicochemical, nutraceutical and organoleptic parameters were evaluated. The results show that the four cultivars are of high overall quality and are generally homogenous among parameters.

Label-free proteomic quantification of packaged Flammulina filiformis during commercial storage

Abstract Fresh Flammulina filiformis is perishable and undergoes dynamic postharvest changes in physiological metabolism and biochemistry. In this study, we use label-free quantitative proteomics to elucidate the mechanisms of F. filiformis responses to cold storage and internal packaging stimuli. External quality including weight, browning, stipe elongation and cap opening were characterized during 21 d of commercial storage at 4 ℃. Among the 291 proteins identified from fresh and stored F. filiformis, we detected 39 upregulated and 73 downregulated differentially expressed proteins (DEPs). After 9 d of storage, 19 % of the upregulated DEPs were involved in the tricarboxylic acid (TCA) cycle, whereas 32 % of the downregulated DEPs were associated with translation. At the end of the storage period, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that most DEPs were involved in antibiotics biosynthesis, carbon metabolism and amino acid metabolites. Our results illuminate the biological processes occurring in F. filiformis under commercial storage conditions and provide a theoretical basis for the quality control of fresh F. filiformis.

Insecticidal Efficacy of Three Nanoparticles for the Control of Khapra Beetle (Trogoderma granarium) on Different Grains

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is an important pest of stored wheat worldwide. Nanoparticles have become one of the most promising new tools for insect pest management in recent years. This laboratory study was conducted to evaluate the insecticidal efficacy of three commercially available nanoparticles [silicon oxide (SNPs), aluminium oxide (ANPs) and zinc oxide (ZNPs)] against T. granarium at 50, 100 and 200 mg kg–1. The efficacy of SNPs, ANPs and ZNPs on wheat, barley, rice, white maize and yellow maize was assessed after 1, 3, 5 and 7 d of exposure. Corrected mortality of T. granarium was significantly affected by nanoparticle types, application rates, grain types, and the insect developmental stages. SNPs and ANPs were more effective than ZNPs, where 100% mortality of second instars was obtained at the highest concentration. Mortality of second instars on wheat treated with SNPs, ANPs or ZNPs at the rate of 200 mg kg–1 was significantly higher than other concentrations. Insecticidal efficacy of all nanoparticles at the rate of 200 mg kg–1 against second instars was significantly higher on barley and wheat than those on rice and maize. First, second and third instars exposed to all nanoparticle types at the rate of 200 mg kg–1 were more susceptible than fourth and fifth instars and adults. Female adults exposed to wheat treated with all nanoparticles at the rate of 200 mg kg–1 stopped reproduction completely. The results demonstrate that commercially available SNPs and ANPs can be used as eco-friendly management strategy of T. granarium; however, further studies under commercial storage conditions are required.

Shelf life extension of fresh asparagus using modified atmosphere packaging and vacuum skin packaging in microwavable tray systems

Asparagus (Asparagus officinalis L.) is one of the most popular vegetables because it contains a wealth of fiber and several essential nutrients. It is a very perishable commodity due to its very high respiration rate. To maintain product quality and to satisfy consumer demand as a convenient food, modified atmosphere packaging (MAP), vacuum skin packaging (VSP), and microwaveable containers were used to extend the shelf life of fresh‐cut asparagus as a ready‐to‐eat food product. The objective of this study was to determine the shelf life of fresh‐cut asparagus packed in MAP and VSP microwaveable tray systems at commercial storage conditions, 4°C, 80% RH. Weight loss, moisture content, O2/CO2 concentration in the package headspace, product pH, microbial growth, and sensory evaluation were used to determine the product quality and shelf life. Moreover, the preference of product appearance and the quality of the cooked asparagus in both microwaveable tray systems at different cooking times and microwave power levels was also sensorially evaluated. During storage for 21 days, there was no significant difference (p &gt; 0.05) in weight loss, moisture content, and pH. Sanitation and packaging techniques also helped to retard the microbial growth. Both techniques, combined with refrigeration, help to maintain the freshness and product shelf life up to 21 days for MAP and 18 days for VSP. On the basis of hedonic scale results, consumers preferred the appearance of both packaging types. Both microwavable tray systems, thus, can help to prolong the shelf life of fresh‐cut asparagus and can be eaten directly from the package.

Metabolite Changes during Postharvest Storage: Effects on Fruit Quality Traits.

Metabolic changes occurring in ripe or senescent fruits during postharvest storage lead to a general deterioration in quality attributes, including decreased flavor and ‘off-aroma’ compound generation. As a consequence, measures to reduce economic losses have to be taken by the fruit industry and have mostly consisted of storage at cold temperatures and the use of controlled atmospheres or ripening inhibitors. However, the biochemical pathways and molecular mechanisms underlying fruit senescence in commercial storage conditions are still poorly understood. In this sense, metabolomic platforms, enabling the profiling of key metabolites responsible for organoleptic and health-promoting traits, such as volatiles, sugars, acids, polyphenols and carotenoids, can be a powerful tool for further understanding the biochemical basis of postharvest physiology and have the potential to play a critical role in the identification of the pathways affected by fruit senescence. Here, we provide an overview of the metabolic changes during postharvest storage, with special attention to key metabolites related to fruit quality. The potential use of metabolomic approaches to yield metabolic markers useful for chemical phenotyping or even storage and marketing decisions is highlighted.

The Great Five\u2014an artificial bacterial consortium with antagonistic activity towards Pectobacterium spp. and Dickeya spp.: formulation, shelf life, and the ability to prevent soft rot of potato in storage

“The Great Five” (GF) is an artificial bacterial consortium developed to protect potato tubers from soft rot caused by Pectobacterium spp. and Dickeya spp. To investigate the commercialization potential of the GF, we developed liquid and powder formulations of the consortium and of each of the comprising strains (Serratia plymuthica strain A294, Enterobacter amnigenus strain A167, Rahnella aquatilis strain H145, Serratia rubidaea strain H440, and S. rubidaea strain H469). To form powders, the cells were lyophilized using a newly developed lyoprotectant: Reagent PS. The shelf life of the formulations stored at 8 and 22 °C was monitored for a period of 12 months. The longest shelf life was obtained for formulations stored at 8 °C; however, the viability of all formulations was negatively affected at 22 °C. For the consortium, a 2.5 log10 cfu (colony forming units) drop in cell number was recorded for the liquid formulation after 6 months, while in case of powders, the drop remained below 1 log10 cfu following 12 months. The ability of the powder formulations to preserve biocontrol activity of the consortium was tested on potato tubers treated with the formulations and a mixture of the soft rot pathogens. The inoculated tubers were stored for 6 months at 8 °C to mimic commercial storage conditions. Soft rot severity and incidence on potato tubers treated with formulations were significantly reduced (62–75% and 48–61%, respectively) in comparison to positive control with pathogens alone. The potential use of the newly developed formulations of “The Great Five” for the biocontrol of soft rot is discussed.Key Points• An innovative reagent to protect bacterial cells during lyophilization was developed.• Powder formulations of “The Great Five” prolonged its shelf life.• The powder-formulated “The Great Five” was active against soft rot bacteria on potato tubers.

The effect of Neem oil in controlling Khapra beetle Trogoderma granarium (Dermestidae : Coleoptera) and reducing its associated fungal isolates in wheat grains

The khapra beetle, Trogoderma granarium is an important pest of stored wheat worldwide. The current study was carried out to evaluate the lethal and the sublethal three concentrations of neem oil on T. granarium. We also assessed the effect of neem oil on the growth of fungal species associated with T. granarium infected wheat grains. The results demonstrate that treating of wheat grains with 5% neem caused the highest mortality of T. granarium (82.3%). The results were also shown that application of neem oil decreased the percentage of weight loss of wheat grains and the percentage of egg hatching. In addition, the total number of fungal isolates associated with T. granarium infecting neem-treated wheat grains were 4 fungal isolates, compared to 13 fungal isolates from untreated wheat grains. The results demonstrate that neem oil has potential use as a biological control agents of T. granarium; however, further studies under commercial storage conditions are required.

Water sorption isotherms of cooked hams as affected by temperature and chemical composition

Abstract This study was focused on the determination of the chemical composition and experimentally obtaining the sorption isotherms for four samples of commercial cooked ham subjected to simulated commercial storage conditions. The isotherms were determined using the gravimetric method. The mathematical models of Guggenhein, Anderson and de Boer; Brunauer, Emmett and Teller; Halsey; Henderson; and Peleg were fitted to the experimental data. The Guggenhein, Anderson and de Boer model was chosen to best describe the isotherms as it had a very good fit. The increase in temperature reduced the equilibrium moisture content of the product. Increased relative humidity resulted in an increase in equilibrium moisture content of the product regardless of storage temperature. The differences in chemical composition between the samples affect the desorption isotherms. The higher the content and availability of the protein or the lower the fat content, the higher the equilibrium moisture content of the product.

Harvest Maturity and Storage Temperature Affect Postharvest Quality of ‘Wanda’ Datil Hot Pepper Grown under Protected Culture

Datil hot pepper (Capsicum chinense) has potential for increased production due to its unique, spicy flavor and aroma. However, few reports have been published related to postharvest handling characteristics. The purpose of this study was to determine the effect of harvest maturity on fruit quality under simulated commercial storage conditions. ‘Wanda’ datil pepper plants were grown hydroponically under protected culture. Fruit were harvested at yellow and orange maturity stages, placed in vented clamshell containers, and stored at 2, 7, or 10 °C for 21 days. Peppers harvested at yellow stage maintained greater quality than orange peppers during storage at all temperatures. Marketable fruit after 21 days for peppers harvested at the yellow stage was 94% (2 °C), 88% (7 °C), and 91% (10 °C); that for orange-stage peppers was 68%, 74%, and 82% for the same respective temperatures. No chilling injury (CI) symptoms were observed in these tests. Initial pepper moisture content was 90%, decreasing only slightly during 21 days of storage; weight loss ranged from 2% to 8%. Soluble solids content (SSC) was greater for peppers harvested at the orange stage (9.5%) than for those at yellow stage (7.8%). Neither harvest maturity nor storage temperature affected total titratable acidity (TTA; 0.13%) or pH (5.3). Respiration rate varied with temperature but not by harvest maturity and ranged from 12 to 25 mg·kg−1 per hour after 8 days of storage. Peppers harvested orange contained double the amount of total carotenoids as yellow fruit. Carotenoid content for yellow and orange peppers was 58 and 122 µg·g−1, respectively. Capsaicinoid content ranged from 1810 to 4440 µg·g−1 and was slightly greater for orange-harvested peppers. Datil peppers harvested at the yellow stage and stored in vented clamshell containers had better quality than peppers harvested at the orange stage after 21 days at 2 °C.

Increasing shelf life of strawberries (Fragaria ssp) by using a banana starch‐chitosan‐Aloe vera gel composite edible coating

SummaryStrawberries are among the most consumed fruits in the world, however, they are highly susceptible to both microbial and fungal contamination during storage. In this study, we used composite films made from banana starch‐chitosan and Aloe vera gel (AV gel) at different AV gel concentrations. Our results show that AV gel inclusion can significantly reduce fungal decay, increasing strawberries shelf life up to 15 day of storage at the highest AV gel concentration (20%), while maintaining their physicochemical properties, such as colour and firmness. Weight loss was reduced 5% with respect of the uncoated fruit. Our results can be attributed to the limited water vapour transfer allowed by the edible coating, this is the result of the crosslinking effect of the different AV gel and starch molecules that allows a more controlled decay of the strawberries in commercial storage conditions.

Techno-functional properties and sustainable application of nanoparticles-based Lavandula angustifolia essential oil fabricated using unsaturated lipid-carrier and biodegradable wall material

As a non-thermally stable product, nanoemulsion followed by an encapsulation process was fabricated to enhance the techno-functional performance and sustainable applications of Lavandula angustifolia essential oil (La.EO). Integrated ultrasound-microwave techniques were used to enhance the release of Clevenger-hydrodistillation isolation of La.EO. Refined, bleached, and deodorized sunflower oil (RBDSFo) was used as a high unsaturated lipid-carrier type. Whey Protein Isolate (WPI, 95%) was used as a natural-biodegradable polymer wall material to formulate and stabilize Oil-in-Water nanoemulsion (O/W-NE). DLS, CLSM, and TEM were used to study the techno-functional characteristics of La.EO-nanoparticles. SEM, XRD, and FTIR spectroscopy were used to study the efficiency of the encapsulation process of La.EO. The fabricated formulations using a High-pressure Homogenizer showed a highly efficient at reducing the interfacial tension of O/W-NE interfaces. That led to produce nano-scaled droplets reached 128.8 d.nm with a polydispersity index of 0.151, and a ζ-potential of −42.1 mV. The optimized formulation of nanoemulsion showed a slight change in droplet size, PdI, and ζ-potential through 28 days of storage at ambient temperature. La.EO-nanoemulsion was stable against aggregation and coalescence at thermal destabilizing stresses similar to that can be exposed to in the commercial storage conditions (5, 25 and 45 °C) at neutral pH. The findings of this investigation showed that the thermal stability of La.EO can be enhanced through the encapsulation process within edible bio-polymers using both WPI and RBDSFo. In addition, La.EO nanoparticles demonstrated a great potential to be used to enhance the release of bioactive components coated in O/W-NE, as well as, to be used as pathogenic antibacterial agents.