Simulated Cold Chain Research Articles

Synergistic effect of red-white LED and modified atmosphere packaging on okra quality maintenance and its mechanism in simulated cold chain logistics

Okra is rich in nutritional value, but transportation vibration, cold chain breakage and improper storage can quickly accelerate quality deterioration. In this study, we simulated the cold chain transportation process to find the synergistic effect of red-white LED illumination combined with modified atmosphere packaging (MAP) on okra quality maintenance and its mechanism of action. After 16 d of storage, LED+MAP can better avoid water loss and wilting in okra. The fracturability was 35 %, 33 %, and 40 % of fresh okra for LED, MAP, and LED+MAP, respectively, compared to 17 % for CK. CK produced unpleasant odors, but the odor of LED+MAP was close to the fresh. LED+MAP maintained the stability of the nutrient content of okra. The chlorophyll content of LED+MAP was reduced to 64 % of the original compared to 35 % of that for CK. The total phenol content of LED+MAP was reduced to 55 % of the original compared to 26 % of that for CK. The total flavonoid content of LED+MAP was reduced to 72 % of the original compared to 56 % of that for CK. LED+MAP regulated the activity of antioxidant enzymes, and the antioxidant capacity was significantly higher than that of the other groups. The ascorbic acid content of LED+MAP was reduced to 52 % of the original compared to 38 % of that for CK. The MDA content of LED+MAP was 3.83 times of the original compared to 8.52 times of that for CK. The electrolyte leakage of LED+MAP was 2.12 times of the original compared to 2.86 times of that for CK. With the increase of storage time, O2 concentration in MAP showed a decreasing trend and CO2 showed an increasing trend. O2 in LED+MAP showed a growing trend followed by a decreasing trend and CO2 showed a decreasing trend followed by a rising trend. LED+MAP complemented the shortcomings of the single technology and was more effective in delaying the quality deterioration of okra.

Effects of temperature fluctuations on the quality and microbial diversity of beef meatballs during simulated cold chain distribution.

Cold chain distribution with multiple links maintains low temperatures to ensure the quality of meat products, whereas temperature fluctuations during this are often disregarded by the industry. The present study simulated two distinct temperatures cold chain distribution processes. Quality indicators and high-throughput sequencing were employed to investigate the effects of temperature fluctuations on the quality and microbial diversity of beef meatballs during cold chain distribution. Quality indicators revealed that temperature fluctuations during simulated cold chain distribution significantly (P < 0.05) exacerbated the quality deterioration of beef meatballs. High-throughput sequencing demonstrated that temperature fluctuations affected the diversity and structure of microbial community. Lower microbial species abundance and higher microbial species diversity were observed in the temperature fluctuations group. Proteobacteria and Pseudomonas were identified as the dominant phylum and genus in beef meatballs, respectively, exhibiting faster growth rates and greater relative abundance under temperature fluctuations. The present study demonstrates that temperature fluctuations during simulated cold chain distribution can worsen spoilage and shorten the shelf life of beef meatballs. It also offers certain insights into the spoilage mechanism and preservation of meat products during cold chain distribution. © 2024 Society of Chemical Industry.

Enhanced Heat Transfer in Thermoelectric Generator Heat Exchanger for Sustainable Cold Chain Logistics: Entropy and Exergy Analysis

This study investigates the application of thermoelectric power generation devices in conjunction with cold chain logistics transport vehicles, focusing on their efficiency and performance. Our experimental results highlight the impact of thermoelectric module characteristics, such as thermal conductivity and the filling thickness of copper foam, on the energy utilization efficiency of the system. The specific experimental setup involved a simulated logistics cold chain transport vehicle exhaust waste heat recovery thermoelectric power generation system, consisting of a high-temperature exhaust heat exchanger channel and two side cooling water tanks. Thermoelectric modules (TEMs) were installed between the heat exchanger and the water tanks to use the temperature difference and convert heat energy into electrical energy. The analysis demonstrates that using high-performance thermoelectric modules with a lower thermal conductivity results in better utilization of the temperature difference for power generation. Additionally, the insertion of porous metal copper foam within the heat exchanger channel enhances convective heat transfer, leading to an improved performance. Furthermore, the study examines the concepts of exergy and entropy generation, providing insights into the system energy conversion processes and efficiency. Overall, this research offers valuable insights for optimizing the design and operation of thermoelectric generators in cold chain logistics transport vehicles to enhance energy utilization and sustainability.

Evaluation of a Calcium Carbonate-Based Container for Transportation and Storage of Fresh Fish as a Sustainable Alternative to Polystyrene Boxes

The present study aimed to assess the effect of alternative packaging materials on the quality retention and shelf-life of whole fish under low and abuse temperature conditions. Red sea bream (Pagrus major) was harvested and stored in different packaging containers, i.e., a conventional polystyrene (PS) box, a CaCO3-based box and a cardboard box (tested as a simple alternative container for transportation and short-term storage of food). After harvesting and transportation, fish was stored in the tested containers at 2 °C for 11 days and periodically kept at room temperature (25 °C) to simulate potential temperature fluctuations in the actual supply chain. The effect of temperature fluctuations and packaging materials on the quality and remaining shelf-life of fish was determined by microbial enumeration (total viable counts, Pseudomonas spp. and Enterobacteriaceae). PS retained fish quality and maintained a low temperature of fish for longer periods of time during storage at ambient conditions. The CaCO3-based containers also showed satisfactory performance, resulting in a similar microbial load in fish flesh to the samples stored in PS boxes after 11 days of simulated transportation and storage (TVC load 7.8–8.0 logcfu/g). Cardboard resulted in a rapid increase in the internal temperature during the temperature fluctuations at ambient conditions, resulting in higher microbial loads of fish flesh at all stages of the simulated cold chain. The replacement of conventional plastic packaging materials with alternative, environmentally friendly packaging systems without affecting the shelf-life of fish may reduce plastic waste while ensuring the high quality and shelf-life of perishable food products.

Effect of vibration and broken cold chain on the evolution of cell wall polysaccharides during fruit cucumber (Cucumis sativus L.) shriveling under simulated transportation

The fruits and vegetables often result in shriveling, which can significantly affect the quality in terms of texture, appearance, and saleable weight during transportation and storage. In this study, fruit cucumbers (Cucumis sativus L.) were subjected to vibration followed by storing them under isothermal and non-isothermal conditions (simulated broken cold chain) for 15 days. Water movement, cell wall polysaccharides and degrading enzymes, cell wall structure of cucumbers were determined. The findings revealed that water initially migrated from the inner pericarp of cucumber. Vibration and broken cold chain damaged the fruit cell wall and cell wall polysaccharides, and increased degrading enzymes, which promoted the water movement from the tissues to the exterior, causing severe shriveling of cucumber. Firmness loss accompanied with cucumber shrivel appeared by as early as 6 days of storage after vibration (5.5 Hz), with decrease of 19.88–29.93 %. However, this phenomenon was not observed in the control cucumber until 12 days after storage with firmness of 8.22 N. Therefore, this study shows that simulated transport vibration and broken cold chain could cause intracellular damage in cucumber tissues, which expedites the process of water loss, degradation of cell wall polysaccharides and shriveling process. The study also reveals that precise temperature control and avoiding vibration of transportation in cold chain logistics of cucumbers are important in maintaining the product quality during storage and transport.

Failure Mechanism of the Corrugated Medium under Simulated Cold Chain Logistics.

It is necessary to develop corrugated medium food packaging, which is suitable for highly humid environments, to meet the demands of cold chain logistics. In this paper, we investigated the influence of the transverse ring crush index of different environmental factors of corrugated medium and the failure mechanisms during cold chain transportation. After freeze-thaw treatment of corrugated medium, XRD and DP showed a decrease in crystallinity and polymerization of 3.47 and 7.83%, respectively. Also, the FT-IR spectra of the paper showed that the number of intermolecular hydrogen bonds decreased by about 3.00% after freezing. SEM and XRD showed CaCO3 precipitation on the paper surface and a 26.01% increase in pore size. This study would be beneficial in further expanding the applications of cellulose-based paperboard cold chain transportation.

Inactivation of porcine epidemic diarrhea virus with electron beam irradiation under cold chain conditions.

The many instances of COVID-19 outbreaks suggest that cold chains are a possible route for the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, owing to the low temperatures of cold chains, which are normally below 0 °C, there are limited options for virus inactivation. Here, high-energy electron beam (E-beam) irradiation was used to inactivate porcine epidemic diarrhea virus (PEDV) under simulated cold chain conditions. This coronavirus was used as a surrogate for SARS-CoV-2. The possible mechanism by which high-energy E-beam irradiation inactivates PEDV was also explored. An irradiation dose of 10 kGy reduced the PEDV infectious viral titer by 1.68–1.76 log10TCIDL in the cold chain environment, suggesting that greater than 98.1% of PEDV was inactivated. E-beam irradiation at 5–30 kGy damaged the viral genomic RNA with an efficiency of 46.25%–92.11%. The integrity of the viral capsid was disrupted at 20 kGy. The rapid and effective inactivation of PEDV at temperatures below freezing indicates high-energy E-beam irradiation as a promising technology for disinfecting SARS-CoV-2 in cold chain logistics to limit the transmission of COVID-19.

Feasibility study on early identification of freshness decay of fresh-cut kiwifruit during cold chain storage by Fourier transform-near infrared spectroscopy combined with chemometrics.

This work mainly aimed to evaluate the feasibility of Fourier transform-near infrared spectroscopy (FT-NIRS) combined with chemometrics in early identification of freshness decay of fresh-cut kiwifruit during simulated cold chain storage, with organoleptic evaluation as a reference. By linear discriminant analysis, the freshness decay could be identified after only 2 days of cold storage, corresponding to freshness level of 3.41± 0.27 N (hardness), 0.70± 0.05g/kg (total acid), 8.62± 0.06g/100g(reducing sugars), 62.04± 1.03mg/100g(vitamin C) and 2.05± 0.11 log10 CFU/g (total plate count). Organoleptic evaluators could not perceive the freshness decay that occurred after 2 days of cold storage. Moreover, the freshness decay could be well quantitatively predicted by partial least squares regression, with low RMSEp (0.18-05.42) and high R2 (0.90-0.96). FT-NIRS appears to be a promising option for early warning of the freshness decay of fresh-cut kiwifruit during cold chain storage, thereby preventing serious spoilage and ensuring fresh fruits for consumers. PRACTICAL APPLICATION: This work is based on the fact that fresh-cut kiwifruit is prone to freshness decay under unstable cold chain conditions, using FT-NIRS combined with chemometrics to identify the freshness decay early and rapidly, to a certain extent, early warn freshness decay and effectively prevent serious spoilage. The technology can be used for food regulatory agencies to monitor the freshness of fresh-cut kiwifruit, and can also be applied for fruit processing enterprises and dealers to ensure the freshness and high quality of fresh-cut kiwifruit.

A simulated e-commerce cold chain for fresh cod (Gadus morhua L.) products: Applicability of selected TTIs and effects of pre-treatment and packaging

The objective of this work was to study 1) the applicability of two selected time and temperature integrators (TTIs) and 2) the quality effects of different pre-treatments and packaging of fresh cod in a simulated e-commerce cold chain of 16 days. TTIs enables consumers to evaluate the product quality based on its time and temperature history. The first 6 days, the fish was either stored as gutted or gutted and filleted, representing “from business to business” (B2B), while the remaining days “from business to consumer” (B2C) value chain, the fish was packaged and stored at 4 °C in modified atmosphere (MA) or in air. One TTI recorded the temperature, and the other TTI was based on an enzymatic reaction. In B2B, the product core temperature was app. −0.5 °C. In the B2C, shelf life of 7–10 and 5–7 days for MA- and air-packaged products were obtained, respectively. Time for filleting, 1 or 6 days post-mortem for the MA products, did not influence the shelf life in the B2C. The TTI recording the temperature showed a good coherence with the reference temperature, while the reaction based TTI was inconsistent with the actual shelf life. To ensure consistency, the TTI could have been activated earlier. From a consumer's point of view, the information generated by the TTIs is beneficial to avoid the purchase of products of poor sensory quality.

Metabolism and cold chain performance of ‘Chuhwangbae’ Asian pears as impacted by 1-MCP treatment

The ‘Chuhwangbae’ Asian pear, a late-season cultivar that has become popular in Korea, is susceptible to physiological disorders during cold storage. The objective of this study was to evaluate the effect of 1-methylcyclopropene (1-MCP) treatment on fruit quality, physiological disorders, and targeted metabolites of ‘Chuhwangbae’ Asian pear fruit during cold storage and at the post-storage ripening stage. ‘Chuhwangbae’ Asian pear fruit were treated with 1-MCP immediately following harvest, stored at 1 °C for up to 3 months, and subsequently stored at 25 °C for 14 d to ripen. Indicators of fruit quality, namely the incidence of browning disorder and the degree of water loss or “shriveling,” as well as levels of key metabolites, were repeatedly analyzed during the simulated cold chain. Fruit treated with 1-MCP lost more weight but slightly maintained firmness than did untreated fruit during the entire cold chain. Treatment with 1-MCP reduced the severity of flesh browning but enhanced the incidence and severity of shriveling during post-storage ripening after 3 months of cold storage. GABA, histidine, phenylalanine, and tyrosine levels were higher in the flesh of the 1-MCP-treated fruit than in untreated fruit. The results indicate that the overall changes in metabolite levels following 1-MCP treatment were less during cold storage than those during post-storage ripening. Therefore, postharvest 1-MCP treatment could be at least partially effective in retaining flesh firmness and reducing the severity of internal browning of ‘Chuhwangbae’ Asian pears during the entire cold chain.

Potential Use of Oil Palm Fronds for Papermaking and Application as Molded Pulp Trays for Fresh Product under Simulated Cold Chain Logistics

ABSTRACT Waste paper from newsprint, a key feedstock for molded pulp trays, is globally deficient due to digital shifts. Hence, the alternative fiber source needs to be explored. The potential use of fiber from oil palm fronds for protective packaging under humid conditions was studied. Fibers were isolated from petioles by sulfate pulping with 30.72% yield. The high α-cellulose content (38%) showed valuable for papermaking. Runkle’s ratio (0.63), rigidity coefficient (38.46), and slenderness value (100) suggested that the paper would have excellent mechanical properties. Under cold chain logistics, packaging must withstand high humidity and low temperature (90%RH, 12°C). Addition of 1.4% cationic starch and 0.5% AKD significantly enhanced water absorption resistance from 59 to 23250 sec and improved the burst (6.68%) and tensile index (26.47%). The molded pulp trays fabricated from 70% sized frond fibers and 30% OCC fiber provided 7.71% higher compressive strength than neat OCC tray. All physical properties indicated that the as-prepared trays have potential use for protective material. A simulation with green apple demonstrated that the trays were impractical for use with soft-skinned fruit as the dense and rough surface of the packaging. Further study to evaluate cushioning performance for harder skin fruit is, therefore, necessary.

Dissipation behavior, residue dynamics, and dietary risk assessment of forchlorfenuron in postharvest kiwifruits during simulated cold chain logistics and store shelf life.

Forchlorfenuron (CPPU) is often applied during the cultivation of kiwifruit to produce larger fruit. To address degradation patterns of CPPU during simulated cold chain logistics and simulated shelf life of the fruit after harvest, appropriate storage methods and safe consumption behavior can be investigated. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry method was adopted to detect CPPU residues under different conditions. CPPU in kiwifruit stored at 6°C had a half-life of 40.8-77.0days. However, when kiwifruit was stored at 0°C under simulated cold chain storage conditions, the half-life of CPPU was 63.0-115.5days, implying that lower storage temperatures can reduce the degradation rate of CPPU. The residues of CPPU in kiwifruit pulp declined with time, and the reduction followed the first-order kinetics equation. More CPPU residues were present in the pulp of postharvest kiwifruit treated with exogenous ethylene than in the pulp of untreated kiwifruit. Thus, using exogenous ethylene for artificial ripening after harvest is not recommended. We determined that the appropriate cold chain storage temperature is 6°C. It is recommended that the public select kiwifruit stored for at least 2weeks. The estimated chronic and acute dietary risk quotients of CPPU are ≤ 0.79% and ≤ 0.11%, respectively. Therefore, it is highly unlikely that consumers will be poisoned by CPPU due to kiwifruit consumption. Our results provide scientific evidence regarding the adoption of appropriate kiwifruit storage methods and consumption behavior to enhance consumption safety.

A Simulated E-Commerce Cold Chain for Fresh Cod ( Gadus Morhua L.) Products: Applicability of Selected TTIs and Effects of Pre-Treatment and Packaging

The objective of this work was to 1) study the applicability of two selected time and temperature integrators (TTIs) and 2) study the quality effects of different pre-treatments and packaging of fresh cod in a simulated e-commerce cold chain of 16 days. The first 6 days, the fish was either stored as gutted or gutted and filleted, representing “from business to business” (B2B), while the remaining days “from business to consumer” (B2C), the fish was packaged and stored at 4 °C in modified atmosphere (MA) or in air. One TTI recorded the temperature, and the other TTI was based on an enzymatic reaction. In B2B, the product core temperature was approx. –0.5 °C. In the B2C, shelf life of 7–10 and 5–7 days for MA- and air-packaged products were obtained, respectively. Time for filleting, 1- or 6-days post-mortem for the MA products, did not influence the shelf life in the B2C. The TTI recording the temperature showed an acceptable coherence with the reference temperature, while the enzymatic based TTI was inconsistent with the actual shelf life. To ensure consistency, the TTI could have been activated earlier.

Effect of Cold Chain Logistic Interruptions on Lipid Oxidation and Volatile Organic Compounds of Salmon (Salmo salar) and Their Correlations With Water Dynamics.

Lipid oxidation and water migration are important factors in the quality changes of aquatic products. This study investigated the relationship between water migration and lipid oxidation in salmon filets under four different storage conditions (control: 0°C; T1: 4°C; T2 and T3: two temperature fluctuation groups) by detecting thiobarbituric acid–reactive substances, changes of fatty acids, and volatile organic compounds (VOCs), and other quality indicators including redness, microorganism, total volatile basic nitrogen (TVB-N), and water-holding capacity (WHC) were also measured. The results of low-field nuclear magnetic resonance (LF-NMR) showed that more trapped water (T22) turned to form free water (T23) in groups suffering temperature fluctuations. A more significant decrease in fatty acids was found in T2 and T1 groups, especially oleic acid (C18:1n9c), linoleic acid (C18:2n6c), and palmitic acid (C16:0). The VOCs with off-flavors (1-penten-3-ol, 2-penten-1-ol, (Z)-, 1-octen-3-ol, hexanal) in the groups suffered from simulated cold chain interruptions increased faster than the other two groups during storage. T22 was negatively correlated (p < 0.05) with stearic acid (C18:0), 1-penten-3-ol, hexanal, and nonanal, whereas T23 was positively correlated with 1-penten-3-ol, hexanal, and heptanal. Therefore, the temperature fluctuation accelerated the loss of polyunsaturated fatty acids and the increase of unpleasant odors related to water migration.

Performance of Lactobacillus paracasei 90 as an adjunct culture in soft cheese under cold chain interruption

In this work, we simulated cold chain interruptions in soft cheeses of high-moisture to assess their impact on ripening, putting attention on the behaviour of an adjunct culture of Lactobacillus paracasei 90 (L90) when it was added. Temperature variation did not change starter culture levels but it significantly increased L90 population at 60 days in cheeses with cold chain interruption. Cold chain interruptions and adjunct culture led to an increase of the proteolysis levels and produced changes in the carbohydrate fermentation, volatile compounds profiles and sensory scores. In cheeses with cold chain interruptions, L90 did not cause any defects and maintained its capacity of improving flavour and odour intensities by increasing the levels of diacetyl and acetoin, and decreasing pungent taste and compounds associated with rancidity. In addition, samples with adjunct culture presented increased levels of lactic acid without being perceived as a defect by the sensory panel.

A non-invasive method for quantitative monitoring of quality changes and water migration in bigeye tuna (Thunnus obesus) during simulated cold chain logistics using low-field nuclear magnetic resonance coupled with PCA.

Bigeye tuna (Thunnus obesus) is an important fish species worldwide due to its desirable flavour and rich nutrition. Cold chain logistics is one of the most common methods to store and sell bigeye tuna (Thunnus obesus). The purpose of this study was to investigate how bigeye tuna (T. obesus) deteriorate during simulated cold chain logistics with fluctuating temperatures by monitoring the quality changes and water distribution. The physical and chemical results showed that the sensory score, texture profile analysis (TPA), and water holding capacity (WHC) decreased, while total volatile basic nitrogen (TVB-N), K value, aerobic plate counts (APC), and psychrotrophic bacterial counts increased with fluctuating temperatures during 132 h. Low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) detection showed that the T21 (trapped water) and proton density decreased, while T22 (free water) decreased initially and then increased, indicating continuous water loss and water migration during storage. Principal component analysis (PCA) revealed that springiness, hardness, chewiness, T21, and sensory score were correlated with each other (p < 0.05) and the linear combination of quality indicators and T2transverse relaxation time was established. Besides, temperature fluctuation (batch 3) accelerated the deterioration of bigeye tuna according to the comprehensive score of PCA. Results were based on LF-NMR which can be used to monitor quality changes in a fast non-invasive manner.

Water dynamics and microbial communities of bigeye tuna (Thunnus obesus) during simulated cold chain logistics

AbstractThis study investigated changes in the physicochemical indexes, water dynamics, and microbial communities of bigeye tuna (Thunnus obesus) during simulated cold chain logistics. With increasing storage time, the color and water activity decreased gradually, while drip loss gradually increased, and pH increased with a fluctuating pattern. The trend of bound water content was not obvious, trapped water declined, and free water increased with fluctuations over time, according to low‐field nuclear magnetic resonance (LF‐1H NMR). High‐throughput sequencing results indicated that fluctuating temperatures inhibited Acinetobacter and Pseudomonas and promoted Pelomonas, Psychrobacter, and Shewanella. Principal component analysis and redundancy analysis revealed significantly different microbial community interactions among the four groups, and environmental factors had distinct effects on bacterial community assemblages. LF‐NMR and high‐throughput sequencing can be used to monitor dynamic quality changes in bigeye tuna during simulated cold chain logistics with fluctuating temperatures.

Textural and quality changes of hairtail fillets (Trichiurus haumela) related with water distribution during simulated cold chain logistics.

This study investigated the total viable counts, sensory and physicochemical qualities (total volatile basic nitrogen, K-value, thiobarbituric acid reactive substances value, water holding capacity and texture parameters), as well as water distribution of fresh hairtail fish during simulated cold chain. The results showed that total volatile basic nitrogen, thiobarbituric acid reactive substances and K-values increased with the increasing time, while sensory scores, water holding capacity, hardness and elasticity decreased. The transverse relaxation time T2 data detected by low-field nuclear magnetic resonance also showed that T22 (trapped water) gradually decreased with the increasing time, while T23 (free water) increased. It was observed that the quality deterioration of the fish fillets developed more quickly when the samples suffered frequent temperature fluctuations than they stored at higher but stable temperatures. The changes of T22 and T23 of both the samples stored at stable and fluctuated temperatures showed good correlations with sensory, total volatile basic nitrogen and thiobarbituric acid reactive substances values (R2 > 0.9, p < 0.05). Therefore, low-field nuclear magnetic resonance technology can be a potential tool to monitor the quality changes of hairtail fish during cold chain logistics.

Effectiveness of polymeric coated films containing bacteriocin-producer living bacteria for Listeria monocytogenes control under simulated cold chain break

Nisin, enterocin 416K1 and living bacteriocin-producer Enterococcus casseliflavus IM 416K1 have been entrapped in polyvinyl alcohol (PVOH) based coatings applied to poly (ethylene terephthalate) (PET) films, and their effectiveness in the control of the growth of Listeria monocytogenes ATCC 19117 has been tested. The anti-listerial activity of the doped coated films was evaluated by both a modified agar diffusion assay and a direct contact with artificially contaminated precooked chicken fillets stored at 4 °C, 22 °C and under simulated cold chain break conditions (1 day at 30 °C).The live-Enterococcus-doped film showed a more remarkable activity than nisin- and enterocin-doped films over long times both at 4 °C and 22 °C. The use of this film at 22 °C resulted in full inactivation of L. monocytogenes from the seventh day of the test. Live-Enterococcus-doped film displayed a much better antilisterial activity in comparison to nisin- and enterocin-doped films also in samples incubated at 4 °C, and submitted at one day (3rd or 7th day) of storage at 30 °C, to simulate cold chain break conditions. All results suggest that the live-Enterococcus-doped film can behave as a smart active food packaging, very effective in cold chain break conditions when the Listeria growth is fast.

Development of a Fresh-cut Product Based on Pears and the Subsequent Evaluation of Its Shelf Life under Commercial Conditions and after a Cold Chain Break

Processing of pears as a fresh-cut product could offer added value and introduce a product into the market that offers greater convenience and health benefits for consumers. Cultivar selection is one of the most important considerations for fresh-cut fruit processing because characteristics such as flesh texture, skin colour, and browning potential can vary greatly among cultivars. Four pear cultivars (‘Flor de invierno’, ‘Passe-Crassane’, ‘Ercolini’ and ‘Conference’) and four antioxidant treatments, that is, (NS) 50 g L-1 NatureSeal® AS1 (Agricoat) solution, (AsAc) 20 g L-1 ascorbic acid + 10 g L-1 citric acid + 10 g L-1 calcium chloride solution, (CaAs) 20 g L-1 calcium ascorbate + 10 g L-1 calcium chloride solution and (NaAs) 20 g L-1 sodium ascorbate + 10 g L-1 calcium chloride solution, were tested to obtain a high-quality fresh-cut pear. For the selected cultivar and treatment, the nutritional changes and physicochemical, microbial and sensorial quality were evaluated under conditions that simulated commercial application followed by storage at 4 °C and a simulated cold chain break at 8°C. The ‘Conference’ pear was selected as the best cultivar based on its physicochemical characteristics (high levels of soluble solids content and low acidity), low increase in browning index, and visual acceptance after 7 days of storage. The results demonstrated that CaAs maintained the fresh-cut pear quality after 8 days of storage at 4°C and also after a cold chain break. Furthermore, application of the selected treatment produced an increase in the ascorbic acid content, total phenolic content and antioxidant activity of minimally processed pear samples. These values were reduced during shelf life, but the total phenolic content at the final sampling point was higher than that of fresh-cut pears after processing without treatment.