Postharvest Cold Storage Research Articles

Preharvest Application of Chitosan Improves the Postharvest Life of 'Garmrok' Kiwifruit through the Modulation of Genes Related to Ethylene Biosynthesis, Cell Wall Modification, and Lignin Metabolism.

The influence of the preharvest application of chitosan on physicochemical properties and changes in gene expression of ‘Garmrok’ kiwifruit during postharvest cold storage (0 °C; RH 90–95%; 90 days) was investigated. Preharvest treatment of chitosan increased the fruit weight but had no significant effect on fruit size. The chitosan treatment suppressed the ethylene production and respiration rate of kiwifruit during the cold storage. The reduction of ethylene production of chitosan-treated kiwifruit was accompanied with the suppressed expression of ethylene biosynthesis genes. Moreover, preharvest application of chitosan diminished weight loss and delayed the changes in physicochemical properties that include firmness, soluble solids content, titratable acidity, total sugars, total acids, total phenols, and total lignin. As a result, the preharvest application of chitosan delayed the maturation and ripening of fruit. Expression of genes related to cell wall modification was down-regulated during the early maturation (ripening) period, while those related to gene expression for lignin metabolism were up-regulated at the later stages of ripening. These results demonstrate that the preharvest application of chitosan maintained the fruit quality and extends the postharvest life of ‘Garmrok’ kiwifruit, possibly through the modulation of genes related to ethylene biosynthesis, cell wall modification, and lignin metabolism.

Carotenoids, Vitamin C, and Antioxidant Capacity in the Peel of Mandarin Fruit in Relation to the Susceptibility to Chilling Injury during Postharvest Cold Storage.

Chilling injury (CI) is a postharvest disorder occurring in the fruit of cold-sensitive Citrus species during storage at low temperatures. This study investigated the involvement of carotenoids and vitamin C, two major antioxidants of citrus peel, and the antioxidant capacity in the CI susceptibility of mandarin fruit. To that end, the fruit of three commercial varieties, Fortune, Nova, and Nadorcott, with significant differences in CI susceptibility, were selected. By on-tree fruit bagging, carotenoids and vitamin C contents were modified, and a differential effect of each cultivar on CI was observed. Carotenoid analysis in the peel revealed a strong negative correlation between total carotenoid concentration (TCC) at harvest, and specifically of β-cryptoxanthin and violaxanthin, and CI index at the end of storage. In contrast, vitamin C content was significantly and positively correlated with CI susceptibility. The antioxidant activity assessed by the DPPH• and FRAP reflected the contribution of vitamin C to the antioxidant system, while the SOAC assay correlated positively with TTC, β-cryptoxanthin, and violaxanthin. Collectively, the antioxidant capacity of carotenoids at harvest, as efficient singlet oxygen quenchers, suggests a protective role against the development of CI in mandarin fruit, while vitamin C is not likely playing a critical role.

Innovation for food integrity assessment and fraud detection using NIRS as a nontargeted method: Towards intelligent product and process control

This paper introduces the possibilities of using near-infrared spectral sensors as a nontargeted method, and its pivotal importance as a key tool to fight against food fraud, allowing the detection of unexpected alterations or compounds, but with a holistic approach. An example of using this nontargeted approach to determine the optimal duration of postharvest cold storage of oranges is shown. The methodology based on the use of Shewhart control charts that represent the values of spectral distances, and the critical points of this procedure to consider, are presented.

Genome‐wide identification and expression analysis of the B-box gene family in peach fruit during postharvest cold storage and subsequent shelf life

The B-box transcription factor plays an important role in plant growth and development processes. However, information is lacking on the B-box genes in peach (Prunus persica L. Batsch). Many studies have been published on the B-box genes’ response to light, but far fewer on abiotic stress response, especially to low temperature. Here, we identified 22 members of the B-box gene family in peach, and provided an integrated overview of detailed information, phylogenetic analysis, exon–intron structures, conserved motifs, chromosomal distribution, synteny analysis, and cis-elements prediction of each member. Peach fruit were stored at 0 °C and 4 °C for 28 days and subsequent shelf life of three days to investigate the potential role of BBX genes in cold adaption and occurrence of chilling injury (CI) of postharvest peaches. Cis-elements analysis showed that the corresponding low-temperature responsive (LTR) were found in the promoters of peach B-box genes PpBBX3, 6, 10, 12, 15, 19-2, 20, 22, and 26. The expression levels of PpBBX3, 6, 12, 15, 20, and 26 are remarkably increased in fruit without CI during cold storage and subsequent shelf life, but remained at low level in CI fruit. And significant negative correlation was observed between expression of the six genes and the occurrence of CI of peach fruit. These results revealed that PpBBX3, 6, 12, 15, 20, and 26 were related to cold adaption of peaches during storage. The findings established a foundation for functionally characterizing the B-box gene family members and obtained potential candidate genes against cold stress for postharvest peaches.

Curing and low-temperature combined post-harvest storage enhances anthocyanin biosynthesis in blood oranges

Anthocyanins are pigments present in blood oranges which can be enriched by post-harvest cold storage. Additionally, citrus fruits contain appreciable levels of other flavonoids, whose content increases under post-harvest heat treatments. Here, we investigated the effects of curing (37 °C for 3 days) and storage at low-temperature (9 °C) during 15, 30 and 45 days on accumulation of anthocyanins and other flavonoids in Moro and Sanguinelli Polidori blood oranges (Citrus sinensis L. Osbeck). Cured fruits reached up to 191.4 ± 1.4 mg/L of anthocyanins in their juice after cold storage and a 3-fold enrichment of other flavonoids such as flavones and flavanones, compared to 85.7 ± 3.3 mg/L anthocyanins from fruits with cold storage alone. Concomitantly, qPCR analysis showed that curing enhanced upregulation of the main structural and transcription factor genes regulating the flavonoid pathway. GC–MS analysis showed that no unpleasant compounds were generated in the cured plus cold-stored juice volatilome.

Effect of excessive nitrogen on levels of amino acids and sugars, and differential response to post-harvest cold storage in potato (Solanum tuberosum L.) tubers

Nitrogen (N) is an important nutrient for increased potato tuber yield. However, excessive N can decrease tuber quality. Furthermore, the impact of optimal and higher N levels of potato tuber metabolic profile at harvest and cold storage remains unclear. This study aimed to investigate the metabolic profiling of free amino acids and sugars in potato tubers affected by different nitrogen levels (optimal, ON; and excessive, EN) at harvest (AH) and cold storage (CS) (~4 °C, 4 weeks) through untargeted GC–TOF–MS, and targeted UHPLC–QqQ–MS. Carbohydrate content and vacuolar invertase activity (IV) were determined. Principal component analysis of metabolite data indicated a distinct separation between ON and EN treatments at harvest and cold storage. Multivariate data analysis revealed that sucrose, reducing sugars, and free asparagine were the most altered metabolites (VIP > 1 and P < 0.05), which were involved in starch and sucrose metabolism, and alanine, aspartate and glutamate metabolism. At harvest, the absolute contents of various free amino acids including asparagine were higher (by 1.3–1.5 fold) in the EN treatment than ON treatment, and this difference was maintained at 4-week cold storage. Under the EN treatment, tuber maturity was reduced, and sucrose accumulation was increased at harvest, while IV was increased after cold storage, reducing sugar also accumulated. These results highlighted the negative effects of EN on free amino acid and sugars metabolism in the post–harvest tubers and provided useful information for understanding the underpinning physiological mechanisms.

Blue Light Does Not Affect Fruit Quality or Disease Development on Ripe Blueberry Fruit During Postharvest Cold Storage

Blueberry fruit are perishable after harvesting due to fruit softening, water loss and susceptibility to pathogens. Light, especially blue light, increases the accumulation of anthocyanins and reduces postharvest decay in some fruits, but the effect of blue light on postharvest fruit quality attributes in blueberries is unknown. In this study, we evaluated the effect of blue light on fruit quality, anthocyanin accumulation and disease development during postharvest cold storage (2 °C–4 °C) in two experiments with southern highbush blueberry ‘Star’ and rabbiteye blueberry ‘Alapaha’. Overall, diurnal blue light did not affect postharvest fruit quality attributes, such as visual defects, fruit compression, skin puncture, total soluble solid content and titratable acidity, in the two cultivars compared with their respective controls (diurnal white light or continuous darkness). Further, there was no effect of blue light on fruit color and anthocyanin accumulation. Fruit disease incidence in ‘Star’ ranged from 19.0% to 27.3% after 21 days and in ‘Alapaha’ from 44.9% to 56.2% after 24 days in postharvest storage, followed by 4 days at room temperature, but blue light had no consistent effect on postharvest disease incidence for either cultivar. Disease progression following artificial inoculations with Alternaria tenuissima and Colletotrichum acutatum in ‘Star’ was not influenced by light treatment prior to inoculation and during fruit storage. In a separate experiment, we tested the effect of blue light on color development in ‘Farthing’, a southern highbush blueberry cultivar with fruit prone to non-uniform ripening, whereby the stem-end remains green as the rest of the fruit turns blue. Although green stem-end spots turned blue over time, there was no statistically significant effect of the blue light treatment. Overall, these data indicate that blue light does not affect fruit quality attributes or disease development in ripe blueberry fruit during postharvest storage in the conditions investigated here.

Quality and Storability of Trellised Greenhouse-Grown, Winter-Harvested, New Sweet Acorn Squash Hybrids

Acorn squash (Cucurbita pepo) is a familiar fruit vegetable in North America, appreciated for its attractive appearance, good flavor, nutritional content and long storage life. A breeding program in Israel has produced three new acorn squash hybrids of enhanced sweetness and flavor. Presently, we evaluated productivity, quality, and storability of these new cultivars in fall plantings. The plants were grown trellised, in an insect-proof greenhouse, for fruit production during the winter to meet consumer demand. The plants were highly productive and bore fruits of superb quality, but there was a high incidence of fungal rots during postharvest cold storage. Pre-treating the fruits with hot water brushing and rinsing before storage was found effective in reducing rot incidence of the fruits stored at 15 °C, but only for one cultivar. Storing the fruits at 10 °C with reduced humidity (Rh 70%) enabled a 3-month shelf life with significantly reduced fruit-rot incidence and minimal effect on fruit quality of all three cultivars. Storage at 20 °C with reduced humidity was suitable for a 1-month period. These protocols for prolonging storage life will help attain controlled, gradual year-round marketing of quality acorn squash at uniform, reasonable price levels for farmers and consumers, and could facilitate overseas export.

Pre-storage nitric oxide treatment enhances chilling tolerance of zucchini fruit (Cucurbita pepo L.) by S-nitrosylation of proteins and modulation of the antioxidant response

Abstract Nitric oxide (NO), a major signalling molecule with various physiological functions in plants, participates in many responses to abiotic disorders such as cold stress. Chilling injury (CI) is the most costly postharvest problem in zucchini fruit (Cucurbita pepo L.), since it diminishes market acceptability and shelf life. This study investigates the effect of NO treatment on zucchini fruit during postharvest cold storage. Fruit were dipped in an aqueous solution of sodium nitroprusside (SNP; 25, 100, and 500 μM) as a NO donor and in potassium ferricyanide (a structural analogue of SNP) and distilled water, both used as controls and responding the same during postharvest cold storage. The results showed that the application of 25 μM SNP treatment reduced weight loss and CI in zucchini fruit during cold storage. S-nitrosylated proteins detected in the exocarp of NO-treated fruit were more abundant than in non-treated fruit. The application of SNP improved the quality of zucchini fruit stored at 4 °C, with a reduction of weight loss, electrolyte leakage, content of malondialdehyde and H2O2, and delayed loss of firmness during cold storage. NO-treated fruit showed a higher activity of superoxide dismutase, ascorbate peroxidase, glutathione reductase, and phenylalanine ammonia lyase during the first days of cold storage. Total antioxidant capacity was higher in the NO-treated fruit during the first days of cold storage, supported also by higher concentrations of phenols. NO appeared to play a regulatory role in the antioxidant balance in zucchini fruit, maintaining the cellular redox homeostasis and thus modulating ROS toxicity, thereby improving fruit quality during cold conservation.

Determining the Effect of Postharvest Cold Storage Treatment on the Survival of Immature Drosophila suzukii (Diptera: Drosophilidae) in Small Fruits.

We evaluated the effect of postharvest cold storage temperature (0.0-2.2°C) and duration (3-5 d) on pupal emergence of single life stage populations of laboratory-generated Drosophila suzukii (Matsumura) and mixed-age populations collected in the field from blackberries, blueberries, strawberries, and raspberries. For field-infested fruit, cold storage at any temperature and duration resulted in less pupal emergence compared with the control held at 20°C, but D. suzukii subjected to higher temperatures and shorter storage durations in caneberries had higher survival. When a single life stage of D. suzukii was exposed to cold storage, pupal emergence was significantly reduced across all fruit types held at 0°C and for most life stages and fruit types held at 1.5 and 2.2°C, dependent on the substrate. Freshly laid eggs exposed to cold storage produced the lowest pupal emergence. Our results suggest using cold storage treatment is an effective postharvest management strategy for small-fruit growers to use on-farm as part of an integrated program to manage D. suzukii infestation. An economic assessment was made to examine the profit implications of an investment in cold storage units to counter pest pressure. Results suggest that investment in a cold storage unit would breakeven in about 4 yr. On farms that already have cold storage installed, we estimated a $0.11/kg decrease in blueberry market price for holding fruit for 3 d. Together, this cost assessment will provide growers with the knowledge to make decisions based on infestation risk and the seasonal sale price of blueberries.

Intermittent warming as an efficient postharvest treatment affects the enzymatic and non-enzymatic responses of pomegranate during cold storage

Limited shelf life of pomegranate makes its cold storage necessary. On the other hand, it encounters chilling injury (CI) incidence at temperatures below 5 oC. Intermittent warming (IW), known as one or more warming periods during cold storage, is a beneficial postharvest treatment for keeping fruit quality. Pomegranate ‘Rabab-e-Neyriz’ fruit were stored at 2 ± 0.5 °C (chilling temperature) and 90 ± 5% relative humidity (RH) for 70 days. IW was performed as one warming period by transferring the fruit to a warm room (1 day at 20 °C with 70% RH). The experimental design was factorial based on a complete randomized design. Experimental factors included 4 temporal points of interruption in storage, i.e., 15th, 25th, 35th or 45th days of storage; 2 levels of warming regime for each interruption date, i.e., warming and control; and 2 levels of sampling time, i.e., immediately after treatment or postponed until the end of the storage period. Treated fruit were compared to controls twice, immediately after treatment and at the end of the storage period. Warming on the 15th day of storage led to higher enzymatic antioxidant activity and phenolic content coincided with lower polyphenol oxidase (PPO) activity in the peel and, as a result, lower chilling injury (CI) damage to the treated fruit compared to control. It was concluded that a successful and commercially applicable method for postharvest cold storage of pomegranate could be the only one warming period prior to the incidence of irreversible damage.

Transcriptome analysis reveals the regulation of metabolic processes during the post-harvest cold storage of pear

Pear is a traditional and economically fruit tree worldwide. With the development of the pear industry, pear fruit post-harvest preservation techniques have become very important. Among them, low temperature preservation technology is most widely used, but the molecular mechanism underlying this process is still unclear. To better understand this, RNA-seq was performed on samples collected at different time points with increasing storage time. Here, 19,610 differentially expressed genes were obtained and annotated into 51 GO terms and 26 KEGG-defined significantly overrepresented pathways. 2475 transcription factors belonging to 50 different families were identified with increasing storage time. Ethylene content increased with storage time and was the highest at 105 days of fruit storage. Accordingly, integrative analysis of gene expression revealed that 14 unigenes were related to the ethylene metabolic pathway. This study provides valuable resources to investigate the genetics of the ethylene metabolic pathways and improve pear storage and preservation technology.

Canopy Position Affect Rind Biochemical Properties of ‘Marsh’ Grapefruit during Postharvest Cold Storage at Non-chilling Temperature

ABSTRACT Effect of canopy position on rind biochemical properties of ‘Marsh’ grapefruit during postharvest non-chilling cold storage was evaluated on fruit harvested from different orchard locations. Inside canopy (IC) and outside canopy (OC) fruits were harvested at commercial maturity from two commercial farms located at KwaZulu-Natal (KZN) and Limpopo (LMP), South Africa, during two seasons. Rind biochemical analyses including color indices, total phenolic concentration, and sugars were performed on harvested grapefruit after Weeks 0, 3, 6, and 9 of cold storage at 7.5 ± 0.5°C. Canopy position showed a high significant (p < .001) effect on rind biochemicals while significant (p < .05) influence of orchard locations was observed on the same parameters. Reducing sugars were more concentrated in IC fruit harvested from both orchard location than OC fruit at Weeks 0 and 3, but inverse results occurred at Weeks 6 and 9. Orchard location significantly (p < .001) influenced vitamin C (14.4, 14.2, 14.4, 14.8 g kg−1) and (12.3, 16.1, 15.9, 14.6 g kg−1) of fruit rind at Weeks 0, 3, 6, and 9 from KZN and LMP, respectively. This study revealed that canopy position can influence rind biochemical properties of ‘Marsh’ grapefruit during non-chilling postharvest cold storage. However, further studies are required to formulate and provide the citrus industries with adequate advice.

Airflow and Thermal Behavior within Peaches Packaging Box Using Computational Fluid Dynamics - A Preliminary Study

Post-harvest cold storage of peaches is an essential element to maintain the quality of the fruits without any loss. This work aims to present a CFD model, to predict airflow patterns and temperature profiles in ventilated packaging systems, during the forced-air cooling of Peaches stored in a cold chamber. Transient CFD simulations are performed for the chamber containing four ventilated boxes and the evaluation of the results show that the temperature removal near the vent holes and the hand holes is relatively high when compared to other regions of the packaging box. This preliminary study reveals the airflow behavior develop an uneven temperature distribution within the box. To overcome the flaws, future work is focused on modifying the vent hole design to improve the airflow phenomenon to maintain the temperature homogeneity throughout the box.&#x0D; Keywords: Peach, Computational fluid dynamics, Airflow, Heat transfer, Packaging

Immediate- and long-term proteomic responses of epicarp from two heat conditioned tangor cultivars stored at low temperature differing in their susceptibility to infection

Abstract Citrus is one of the most relevant horticultural crops worldwide. Among them, tangors are highly appreciated by their distinctively taste and aroma. However, both mandarins and tangors are especially susceptible to cold storage. Low temperature storage is generally used to delay fruit decay and reduce pathogen attack during the postharvest period and is necessary for long overseas transport to distant markets. Fruit quality can be protected by different physical methods aimed at improving the response to cold stress, such as heat treatment (HT). These strategies are also fostered as an environmentally sound option to the use of fungicides. The present work derives from previous studies in which metabolic profiling of two tangor varieties was related with their divergent performance after heat treatment and during postharvest cold storage. That work has been expanded and complemented by the study of the proteome of both type of fruit after heat treatment (HT), followed by 7 d of cold storage, in comparison with non-treated fruit. In contrast to Murcott, Ellendale accomplished an important adjustment of its protein contents when exposed to HT. Immediately after HT and at the beginning of postharvest storage at low temperature, proteome changes suggest that a metabolic shift of carbon toward the enhancement of protective mechanisms (such as the antioxidant system, membranes and protein structure protection and cell wall reinforcement), takes place in the less pathogen susceptible variety. Other defensive mechanisms involving nuclear and mitochondrial DNA preservation or auxin inactivation throughout the postharvest period are further discussed.

Effect of salicylic acid treatment on sensory quality, flavor-related chemicals and gene expression in peach fruit after cold storage

Abstract Salicylic acid (SA) has been used in reducing chilling injury of horticultural crops caused by postharvest cold storage. However, effect of SA on fruit flavor quality in response to chilling need to be further investigated. In the present study, SA treated peach fruit (Prunus persica L. Batsch., cv. Hujingmilu) were stored at 0 °C for 7, 14, 21 and 28 d followed by a subsequent shelf-life at 20 °C, respectively. SA treatment (1 mM) alleviated development of flesh browning and maintained softening ability of peach fruit after cold storage. Electronic nose (e-nose) and electronic tongue (e-tongue) analysis showed separation of SA treated fruit and controls based on discriminant factor analysis (DFA) plots, particular for peaches during 3 d shelf-life after 28 d cold storage (C28dS3). Reduced content of fruity note volatile esters and lactones was observed for peach fruit with extended cold storage, SA treatment maintained significant higher volatiles than controls. Transcript levels of genes derived from volatile ester biosynthesis pathway, including lipoxygenase PpLOX1, hyperoxide lyase PpHPL1, alcohol dehydrase PpADH1 and alcohol acyltransferase PpAAT1, were analyzed using real-time quantitative PCR. For SA-treated peach fruit after cold storage, significant higher transcript levels was detected for the PpLOX1 which encodes the first enzymatic step of the pathway. Regrading to soluble sugars, high sucrose content and low content of fructose and glucose was observed for SA-treated peach fruit. Gene expression analysis revealed higher transcript abundance of sucrose synthase PpSUS4, neutral invertase PpNINV8 and tonoplastic monosaccharide transporter PpTMT2 in peach fruit treated with SA. No significant difference in contents were observed for citric acid, malic acid and quinic acid between SA-treated samples and controls. This study showed that SA treatment alleviated the cold storage-induced reduction of a number of volatiles and sugars, and thereby maintained flavor quality of peach fruit during shelf-life after cold storage.

Hot water treatment to alleviate chilling injury and enhance ascorbate-glutathione cycle in sweet pepper fruit during postharvest cold storage

Sweet pepper (Capsicum annuum L.) fruit are highly perishable vegetable and have a short storage life at ambient temperature. The current handling and storage temperatures, below 7 °C, extend the storage life, but chilling injury (CI) occurs after a longer storage. A pre-storage hot water treatment, dipping sweet pepper ‘Miogi’ fruit in 45 °C hot water for 15 min, substantially induced tolerance of fruit to CI at 6 °C storage, and extended storage life for long duration. This research was conducted to reveal the antioxidantive responses of fruit to pre-heat treatment and chilling storage. The purpose of the present study was to understand the effect of hot water treatment on the alleviation of chilling injury and ascorbate-glutathione cycle involved in sweet pepper fruit. Hot water treatment inhibited the increases in malondialdehyde and hydrogen peroxide levels, and enhanced the increases in ascorbate and glutathione contents compared with the control fruit during storage. The activities of ascorbate-glutathione cycle related enzymes including ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase were higher in hot water treated fruit than in the control fruit during cold storage. These results indicate that the alleviation of CI in sweet pepper fruit by hot water treatment in 45 °C hot water for 15 min might be due to the enhancement of the ascorbate-glutathione cycle by increased activity of related enzymes.

Lysophosphatidylethanolamine delays fruit softening of persimmon (Diospyros kaki)

We investigated the possibility of prolonging the freshness of persimmons (Diospyros kaki) for overseas export. Previous studies aimed at improving the shelf life of harvested persimmons focused on the synthetic gas 1-MCP, an inhibitor of ethylene perception. In this study, the natural lipid compound lysophosphatidylethanolamine (LPE) was applied to prolong the freshness of persimmons. LPE significantly delayed persimmon softening when applied not only during fruit growth, but also after harvest, or after a long period of post-harvest cold storage, simulating conditions of overseas export. LPE suppressed the expression of the softening-related genes ACS1, ACO1, ERF24, DkUGD1, DkCHI3, and DkB-CHI1. These results reveal the effects of LPE on persimmon softening and the related molecular mechanisms and provide evidence that LPE can be used to delay persimmon softening.

Volatile organic compounds of Hanseniaspora uvarum increase strawberry fruit flavor and defense during cold storage.

Volatile organic compounds (VOCs) of antagonistic yeasts are considered as environmental safe fumigants to promote the resistance and quality of strawberry (Fragaria ananassa). By GC‐MS assays, VOCs of Hanseniaspora uvarum (H. uvarum) fumigated strawberry fruit showed increased contents of methyl caproate (5.8%), methyl octanoate (5.1%), and methyl caprylate (10.9%) in postharvest cold storage. Possible mechanisms of H. uvarum VOCs involved in regulations of the defense‐related enzymes and substances in strawberry were investigated during postharvest storage in low temperature and high humidity (2 ± 1°C, RH 90%–95%). Defense‐related enzymes assays indicated H. uvarum VOCs stimulated the accumulation of CAT, SOD, POD, APX, PPO, and PAL and inhibited biosynthesis of MDA in strawberry fruit under storage condition. Moreover, the expression levels of related key enzyme genes, such as CAT, SOD, APX42, PPO, and PAL6, were consistently increased in strawberry fruit after H. uvarum VOCs fumigation.

Effect of pre-harvest exposures to adult Halyomorpha halys (Hemiptera: Pentatomidae) on feeding injury to apple cultivars at harvest and during post-harvest cold storage

The effect of exposing apples to brown marmorated stink bug, Halyomorpha halys, for discrete intervals before harvest and of post-harvest cold storage on feeding injury expression was evaluated in 2011 and 2012. Individual apples from four cultivars in experimental orchards in Virginia and West Virginia, USA were caged soon after fruit set to protect them from insect injury. During each of the four weeks preceding harvest of each cultivar, five adult H. halys were placed in a subset of cages for 7-days, then removed. Control fruit were not exposed. The proportion of injured fruit and the number of external injuries was evaluated at harvest, after which the fruit were held in cold storage for about 5 weeks, followed by assessments of the proportion of fruit injured and the number of external and internal injuries. Most exposure timings resulted in external injury at harvest, but fruit exposed closer to harvest tended to show less injury than those exposed earlier. Fruit from all cultivars showed external injury at harvest, with variation in the proportion of injured fruit among them. The proportion of injured fruit and the number of external injuries tended to increase during post-harvest cold storage in some, but not all cultivars. The number of external injuries at harvest and after cold storage underrepresented the number of internal injuries. Results are discussed in the relation to the length of pre-harvest protection required to mitigate fruit injury from H. halys.