Apple Packinghouses Research Articles

Application of Environmental Monitoring Programs and Root Cause Analysis to Identify and Implement Interventions to Reduce or Eliminate Listeria Populations in Apple Packinghouses

Controlling Listeria in produce packinghouses can be challenging due to the large number of potential contamination routes. For example, repeated isolation of the same Listeria subtype in a packinghouse could indicate persistence in the packinghouse or reintroduction of the same Listeria from an upstream source. To improve understanding of Listeria transmission patterns in packinghouses, we performed a longitudinal study in four apple packinghouses, including testing of 1,339 environmental sponges and whole genome sequencing (WGS)-based characterization of 280 isolates. Root cause analysis and subsequent intervention implementation were also performed and assessed for effectiveness. Listeria prevalence among environmental sponges collected from the four packinghouses was 20% (range of 5–31% for individual packinghouses). Sites that showed high Listeria prevalence included drains, forklift tires and forks, forklift stops, and waxing area equipment frames. A total of 240/280 WGS-characterized isolates were represented in 41 clusters, each containing two or more isolates that differed by ≤50 high-quality single nucleotide polymorphisms (hqSNPs); 21 clusters were isolated from one packinghouse over ≥2 samplings (suggesting persistence or possibly reintroduction), while 11 clusters included isolates from >2 packinghouses, suggesting common upstream sources. Some interventions successfully (i) reduced Listeria detection on forklift tires and forks (across packinghouses) and (ii) mitigated packinghouse-specific Listeria issues (e.g., in catch pans). However, interventions that lacked enhanced equipment disassembly when persistence was suspected typically appeared to be unsuccessful. Overall, while our data suggest a combination of intensive environmental sampling with subtyping and root cause analysis can help identify effective interventions, implementation of effective interventions continues to be a challenge in packinghouses.

Hybrid electrolysis and membranes system for apple packing houses water treatment.

The apple industry uses high flows of potable quality water to transport and clean the apple, which is regularly contaminated. Thus, it is necessary to implement an efficient water treatment system during the industrial process, providing reductions in the intake and release flows. A hybrid system was developed by applying the electrolytic treatment by electrocoagulation using a batch process (Step 1) and a continuous process (Step 2), followed by a microfiltration membrane separation (MSP) process (Step 3). The optimal conditions for removal of organic matter, chemical oxygen demand, total suspended solids (TSS), turbidity, color, and fungi obtained in Step 1 were a hydraulic detention time of 40 min, stirring at 40 rpm, current density of 20 A/m2, pH of 8.00, and temperature of 10 °C. These findings led to a successful implementation in Step 2, which evolved into Step 3, where tests in the combined continuous electrolytic reactor together with MSP showed significant removal rates, notably reaching up to 54% organic matter (OM) removal, 72% chemical oxygen demand (COD) removal, 83% TSS removal, 92% haze and color removal, and 100% mildew removal. The hybrid system proved to be a promising alternative for implementation in the processing industry, minimizing environmental impacts and costs.

Prevalence and distribution of Penicillium expansum and Botrytis cinerea in apple packinghouses across Washington State and their sensitivity to the postharvest fungicide pyrimethanil

ISHS IV International Symposium on Postharvest Pathology: Next Generation Innovation and Commercial Solutions for Postharvest Pathology to Reduce Losses, Enhance Quality, and Ensure Product Safety Prevalence and distribution of Penicillium expansum and Botrytis cinerea in apple packinghouses across Washington State and their sensitivity to the postharvest fungicide pyrimethanil

Prevalence of Listeria Species on Food Contact Surfaces in Washington State Apple Packinghouses.

The 2014 caramel apple listeriosis outbreak was traced back to cross-contamination between food contact surfaces (FCS) of equipment used for packing and fresh apples. For Washington state, the leading apple producer in the United States with 79% of its total production directed to the fresh market, managing the risk of apple contamination with Listeria monocytogenes within the packing environment is crucial. The objectives of this study were to determine the prevalence of Listeria spp. on FCS in Washington state apple packinghouses over two packing seasons and to identify those FCS types with the greatest likelihood to harbor Listeria spp. Five commercial apple packinghouses were visited quarterly over two consecutive year-long packing seasons. A range of 27 to 50 FCS were swabbed at each facility to detect Listeria spp. at two sample times, (i) postsanitation and (ii) in-process (3 h of packinghouse operation), following a modified protocol of the FDA's Bacteriological Analytical Manual method. Among 2,988 samples tested, 4.6% (n = 136) were positive for Listeria spp. Wax coating was the unit operation from which Listeria spp. were most frequently isolated. The FCS that showed the greatest prevalence of Listeria spp. were polishing brushes, stainless steel dividers and brushes under fans/blowers, and dryer rollers. The prevalence of Listeria spp. on FCS increased throughout apple storage time. The results of this study will aid apple packers in controlling for contamination and harborage of L. monocytogenes and improving cleaning and practices for sanitation of the FCS on which Listeria spp. are the most prevalent.IMPORTANCE Since 2014, fresh apples have been linked to outbreaks and recalls associated with postharvest cross-contamination with the foodborne pathogen L. monocytogenes These situations drive both public health burden and economic loss and underscore the need for continued scrutiny of packinghouse management to eliminate potential Listeria niches. This research assesses the prevalence of Listeria spp. on FCS in apple packinghouses and identifies those FCS most likely to harbor Listeria spp. Such findings are essential for the apple-packing industry striving to further understand and exhaustively mitigate the risk of contamination with L. monocytogenes to prevent future listeriosis outbreaks and recalls.

Utility of rapid tests to assess the prevalence of indicator organisms (Aerobic plate count, Enterobacteriaceae, coliforms, Escherichia coli, and Listeria spp.) in apple packinghouses

The 2014 listeriosis outbreak caused by caramel-coated apples was linked to apples cross-contaminated within an apple packing facility. This outbreak has increased the focus on effective cleaning and sanitation methods that must be validated and monitored during apple packing. Thus, rapid and reliable testing methods are necessary for assessing cleanliness in the apple packing industry. The objectives of this study were to assess the prevalence of common indicator organisms [Aerobic plate count (APC), Enterobacteriaceae, coliforms, Escherichia coli, and Listeria spp.] on food contact surfaces (zone 1) in apple packinghouses and to evaluate the utility and accuracy of currently used rapid tests (ATP and glucose/lactose residue swabs). Food contact surfaces were sampled over a 100 cm2 area in five commercial apple packinghouses to evaluate populations of indicator organisms APC, Enterobacteriaceae, coliforms, E. coli (n = 741), and rapid test readings (n = 659). Petrifilm plates were used for the quantification of APC, Enterobacteriaceae, and coliform/E. coli. Rapid tests [ATP swabs (UltraSnap) and glucose/lactose residue swabs (SpotCheck Plus)] were processed on-site. A larger area (0.93 m2) was sampled for the detection of Listeria spp. (n = 747), following a modified protocol of the FDA's Bacteriological Analytical Manual method, and confirmed with PCR and gel electrophoresis via the iap gene. No significant association was found between either rapid test and populations of APC, Enterobacteriaceae, coliforms, E. coli, and Listeria spp. detection. However, recovery of APC (log CFU/100 cm2) was higher with a failed glucose/lactose residue swab surface hygiene result (3.1) than a passed result (2.9) (p = 0.03).Populations of APC, Enterobacteriaceae, and coliforms were significantly different at each unit operation during the packing process (p ≤ 0.05). This study concluded that ATP and glucose/lactose residue rapid tests were poorly suited for determining microbial load since they were not related to populations of any common indicator organisms or the detection of Listeria spp. These findings emphasize the need to utilize a rapid test, which can be a good indicator of residual matter on a surface, along with traditional microbiological methods to assess cleaning and sanitation practices in apple packinghouses.

Food Safety Interventions to Control Listeria monocytogenes in the Fresh Apple Packing Industry: A Review.

Listeria monocytogenes, in fresh and ready-to-eat produce such as whole fresh apples, is of concern as there is no "kill step" in their packing process that would eliminate the pathogenic bacteria. Recent listeriosis outbreaks revealed that insufficient cleaning and sanitation practices in fresh apple packing houses may lead to contamination of fruit with L. monocytogenes. This article discusses three fundamental aspects for ensuring microbiological safety of fresh apples: protection of fresh apples from microbial contamination during the packing process, decontamination intervention techniques, and the challenges in removal of L. monocytogenes from fresh apples. Currently used and novel methods of fresh produce decontamination are discussed and evaluated on their usefulness for the apple packing process. Additionally, present regulatory requirements, possible routes of produce contamination, and bacteria attachment and survival mechanisms are described. Optimum methods for microbial decontamination of whole fresh apples are still to be determined. Critical aspects that should be considered in developing the interventions include apple morphology, conditions and scale of the packing process, and influence of the interventions on apple quality. Evaluation of the currently used and emerging decontamination methods indicated that the hurdle technology and rotating use of sanitizers to avoid development of bacterial biofilm resistance may give the best results, although not conclusively.

Greenhouse gas emissions and energy consumption during the post-harvest life of apples as affected by storage type, packaging and transport

In this study, the life cycle assessment (LCA) has been applied to analyze the greenhouse gas (GHG) emissions and energy requirements in the post-harvest life of apples from the Trentino-South Tyrol region (Northern Italy). Data were collected over four years from two commercial apple packinghouses. The key processes in the supply chain were identified based on direct observation, and different scenarios for conservation, packaging, and transport, as well as the source of electricity were analyzed.The results showed that the packaging was the main contributor to both the global warming potential (GWP, from 68 to 98 gCO2eq per kg of apples) and to the cumulative energy demand (from 1.3 to 1.9 MJ/kg). The cooling process (i.e., initial refrigeration and maintaining the cool temperature) that the fruit undergoes before being stored was the second largest contributor to the environmental effects produced during the apple post-harvest. The use of renewable energy is an attractive option to drastically reduce the GWP of this phase. If long transportation distances need to be covered (for example for export, or distances exceeding 300 km), using rail transport or shipping could cut down substantially the environmental costs. The most favorable environmental performances during the post-harvest of the apple include the storage by controlled atmosphere (CA), the delivering of fruits in large reusable plastic bins and their transport over short distances.

First Report of Penicillium expansum Isolates With Low Levels of Resistance to Fludioxonil From Commercial Apple Packinghouses in Washington State

HomePlant DiseaseVol. 101, No. 5First Report of Penicillium expansum Isolates With Low Levels of Resistance to Fludioxonil From Commercial Apple Packinghouses in Washington State PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Penicillium expansum Isolates With Low Levels of Resistance to Fludioxonil From Commercial Apple Packinghouses in Washington StateA. Amiri, K. A. Mulvaney, and L. K. PanditA. AmiriSearch for more papers by this author, K. A. MulvaneySearch for more papers by this author, and L. K. PanditSearch for more papers by this authorAffiliationsAuthors and Affiliations A. Amiri K. A. Mulvaney L. K. Pandit , Washington State University, Tree Fruit Research and Extension Center, Wenatchee 98801. Published Online:1 Mar 2017https://doi.org/10.1094/PDIS-09-16-1353-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Fludioxonil has been used since 2004 in the state of Washington to control several postharvest pathogens of pome fruit, including Penicillium expansum, the causal agent of blue mold. In a recent survey conducted between February and May of 2016, decayed apples were collected from multiple packinghouses (n = 95) across Washington State. Blue-mold symptomatic fruit were cut in half with a sterile scalpel and a small plug was taken from the inside of the lesion and transferred to Petri plates containing potato dextrose agar (PDA) acidified to pH 3.5 using lactic acid. Plates were incubated for 5 days at 22°C and a mycelial plug was cut from the growing colony and transferred to PDA plates and incubated until sporulation was observed. Isolates were single-spored, stored in 30% glycerol at –80°C, and identified to species level as described by Pitt (2002). A total of 1,200 isolates were collected and tested for sensitivity to fludioxonil using a germ tube elongation inhibition assay on PDA amended with 0.5 and 1.0 µg/ml fludioxonil (Scholar SC, Syngenta Crop Protection, Inc.). The 0.5 µg/ml dose discriminated lab-mutants with low resistance to fludioxonil (Li and Xiao 2008) whereas the 1.0 µg/ml dose was used in this study to detect highly resistant isolates. Overall, germ tube elongation on 0.5 µg/ml-amended PDA was observed in 128 (10.6%) P. expansum isolates, whereas none germinated at 1.0 µg/ml. The ability of fludioxonil to control P. expansum isolates with different levels of sensitivity was evaluated on detached apples. Four sensitive isolates and six isolates with different germ tube length in vitro were tested. Organically grown Red Delicious apples were surface sterilized in 0.8% sodium hypochlorite for 2 min, rinsed twice with tap water, and allowed to dry. Fruit were wounded twice (4 mm wide × 3 mm deep) near the stem-end area and immersed for 30 s in a Scholar SC suspension at 0.78 and 1.25 ml/liter, which correspond to the low and high label rates, respectively. Nontreated fruit were immersed in water and served as controls. Fruit were inoculated 4 h post treatment with 25 µl of spore suspension at 105 spores/ml and incubated for 6 days at 20°C in sealed boxes containing 200 ml of sterile water. Eight fruit were inoculated for each isolate and the assay was repeated twice. All isolates developed blue mold on control fruit, whereas only six isolates characterized with low resistance in vitro developed blue mold lesions on fruit treated with Scholar at 0.78 ml/liter. Disease severity in low-resistant isolates ranged from 51.1 to 71.4% relative to nontreated control. All isolates were fully controlled on fruit treated with the higher labeled rate regardless of their in vitro sensitivity. This is the first report of low resistance to fludioxonil in P. expansum from commercial apple packinghouses in Washington State. The emergence of such a population is likely due to frequent fludioxonil usage in recent years because of the widespread resistance to thiabendazole and the emergence of resistance to pyrimethanil in Washington and Pennsylvania (Caiazzo et al. 2014; Yan et al. 2014), the two other postharvest fungicides registered on pome fruit. These findings warrant continuous resistance monitoring and the implementation of adequate management strategies to avoid selecting for highly resistant pathogen populations.

Imazalil resistantPenicillium isolates from Spanish apple packinghouses

Imazalil tolerant isolates ofPenicillium spp. were recovered from sampling natural spore populations in storage rooms and apples collected from packinghouses in Lleida (Spain). ThePenicillium resistant strains belong to the speciesP. cyaneofulvum, P. variabile, P. rugulosum, P. minioluteum andP. pinophilum. 85% of the tested strains were resistant to imazalil in final concentrations of imazalil ranging from 4,500 µg/ml to 11,000 µg/ml. The resistance of these moulds to this fungicide was constant during successive subcultures. 89% ofPenicillium studied strains produced decay in the determination of parasitic fitness at 10 days.

Citrinin-producing capacity of Penicillium expansum strains from apple packinghouses of Lerida (Spain)

A study of the citrinin producing capacity in 122 Penicillium expansum strains isolated from apples and various locations of apple packaging premises Lleida (Spain) was conducted. Among the strains examined, 46% produced citrinin in a laboratory substrate and 73.2% of these strains were isolated from decayed apples. All citrinin producing strains produced metabolites which inhibited Bacillus cereus and Bacillus subtilis. The majority of the strains producing citrinin in solid substrate also produced citrinin in apples and apple juices.

Pathogenicity and Benzimidazole Resistance inPenicilliumSpecies Recovered from Flotation Tanks in Apple Packinghouses

Three hundred and sixty-eight isolated of Penicillium were recovered from water collected from flotation tanks in four apple packinghouses i southeastern New York. The 345 isolates, which caused blue mold in inoculated apples (Malus domestica), were identified to species and tested for sensitivity to methyl 2-benzimidazolecarbamate (MBC) and diphenylamine (DPA). Sixty-five isolates were P. expansum, 277 were P. auantiogriseum, two were P. citreonigrum, and one was P. dendriticum. Thirty-one isolates of P. expansum were sensitive to MBC (...)