Category Archives: Food Technology

Italy – Hepatitis cases linked to turmeric food supplements in Italy

Food Safety News

Two cases of hepatitis have been associated with a brand of turmeric food supplements, according to Italian health authorities.

The Istituto Superiore di Sanità (National Institute of Health/ISS) reported that two types of turmeric food supplements of the company Ni.va. Di Destro Franco and Masetto Loretta S.n.c., based in Via Padova 56, Vigonza have been recalled.

Curcumina Plus 95 percent with production lot code 18L823 and expiration date of October 2021 and Curcumina 95 percent with production lot code 18M861 and expiration  date of November 2021 are affected.

They were produced by the firm Frama S.R.L. in Noventa Padovana.

ISS reported that the two acute cholestatic hepatitis cases “evolved favorably” but did not give more details on the patients or type of hepatitis involved.

Research – Utilizing kitchen steamers to inactivate Listeria monocytogenes and Salmonella enterica on whole cantaloupe melons

Wiley Online

 

Abstract

Cantaloupes contaminated with Listeria and Salmonella have caused large scale of foodborne illness outbreaks in recent years. Prior research has shown that heat treatment can be used to reduce microbial contaminates on fruit surfaces. However, no study has evaluated the use of kitchen steamers for inactivating foodborne pathogens on cantaloupes. The purpose of this study was to test the sanitization efficacy of three models of electrical kitchen steamers (steamer‐A, ‐B, and ‐C) for eliminating foodborne pathogens on cantaloupe surfaces. Fresh cantaloupes were spot‐inoculated with Listeria monocytogens or Salmonella enterica and kept at 4 or 22 °C for a day before steam treatment for ≤100 s. Test results show that the surface of nonrefrigerated cantaloupes can be decontaminated (with ≥5.0 log reduction) within 60 s using any of the tested steamers. For refrigerated fruits (4 °C), however, only two steamers (steamer‐B and ‐C) decontaminated the cantaloupes within 60 s and they were unable to render the pathogens undetected in enriched samples. Salmonella was more susceptible than Listeria to steam treatment. In conclusion, electrical kitchen steamers can be utilized by consumers to sanitize whole cantaloupes prior to consumption. However, fruit temperature and steamer selection can influence the heating time required for surface sanitization.

Practical applications

Melons with netted rind surfaces, such as cantaloupes, likely have caused more outbreaks because their surface shelters pathogens from being eliminated by conventional washing and sanitization. As whole melons marketed at retail stores typically are not treated due to shelf‐life considerations, the safety of untreated melons can be of concern to consumers, especially among at‐risk populations. This study focused on the evaluation of the use of commercially available kitchen steamers in eliminating foodborne pathogens on cantaloupe surfaces. This study showed that kitchen steamers can be utilized to sanitize whole cantaloupes and also at household level, be a highly beneficial for the average concerned consumer to reduce the risk of pathogens on produce before consumption.

Research – Effects of Package Atmosphere and Storage Conditions on Minimizing Risk of Escherichia coli O157:H7 in Packaged Fresh Baby Spinach

Journal of Food Protection

ABSTRACT

Packaged fresh spinach has been associated with outbreaks of illness caused by Escherichia coli O157:H7. The purpose of this study was to assess the behavior of E. coli O157:H7 in packaged baby spinach in response to storage conditions of temperature and package atmosphere and including effects of inoculation level, spinach leaf damage (cut leaves), internalized or leaf surface contamination, exposure to hypochlorite sanitizer, and package size. Behavior of E. coli O157:H7 inoculated at 2 and 4 log CFU/g on spinach packaged in polymer bags composed of a two-layer laminate (polypropylene and polyethylene) and stored under atmospheres of 20% O2–3% CO2 and 0% O2–15% CO2 (aerobic and anaerobic, respectively) was assessed at 5, 7, 12, and 15°C for up to 14 days. Growth kinetics were calculated using DMFit software. Temperature decreases progressively diminished growth or survival of the pathogen, and an aerobic package atmosphere resulted in longer lag times (4 to 6 days) and lower population levels (0.2 to 1.4 log CFU/g) compared with the anaerobic atmosphere at 15°C. Internalized contamination, leaf cuts, or exposure to 100 ppm of hypochlorite did not result in changes in pathogen behavior compared with controls; however, a growth minimization trend consisting of longer lag times and lower population levels was repeatedly observed in the aerobic compared with the anaerobic package atmospheres. In contrast, growth of indigenous mesophiles and Enterobacteriaceae was unaffected by package atmosphere. Spinach stored at 5 to 7°C in two sizes (5 and 16 oz) of polyethylene terephthalate clamshell packages with ambient air atmospheres was more likely to progress to lower-oxygen conditions in 16-oz compared with 5-oz packages after 7 days of storage (P < 0.05). Practices to maintain aerobic conditions within the package, as well as storage of the package at low temperature, are ways to limit growth of E. coli O157:H7 in packaged spinach.

HIGHLIGHTS
  • Cold aerobic conditions limited survival of E. coli O157:H7 in packaged spinach.

  • Low-oxygen atmosphere increased pathogen risk in temperature-abused packages.

  • Internalization, leaf cuts, and hypochlorite stress did not increase pathogen risk.

  • Large spinach packages trended toward lower-oxygen conditions more than small packages.

  • Maintaining cold aerobic conditions can limit pathogen risk in packaged spinach.

Research – Antibacterial Effects of Phytic Acid against Foodborne Pathogens and Investigation of Its Mode of Action

Journal of Food Protection

ABSTRACT

This study investigated the antimicrobial mechanism of phytic acid (PA) and its antibacterial effects in combination with ethanol. The MIC of PA on Escherichia coli ATCC 11229, Staphylococcus aureus ATCC 6538P, Bacillus subtilis ATCC 6633, and Salmonella Typhimurium CICC 27483 were 0.24, 0.20, 0.26, and 0.28% (w/w), respectively. E. coli ATCC 11229 and S. aureus ATCC 6538P were selected to investigate the mechanism of PA by analyzing its effects at 1/2MIC and at MIC on the cell morphology, intracellular ATP, and cell membrane integrity. Environmental scanning electron microscope images revealed that PA was able to change the cell morphology and disrupt the intercellular adhesion. PA retarded bacterial growth and caused cell membrane dysfunction, which was accompanied by decreased intracellular ATP concentrations. Flow cytometry analysis further revealed that almost all the bacterial cells were damaged after treatment with PA at its MIC for 2 h. Moreover, PA has a synergistic antimicrobial ability when used in combination with ethanol. These results suggested that PA is effective in inhibiting growth of foodborne pathogens mainly by the mechanism of cell membrane damage and to provide a theoretical basis for the development of natural antimicrobial agents in the food industry.

Research – Response to Questions Posed by the Food and Drug Administration Regarding Virulence Factors and Attributes that Define Foodborne Shiga Toxin–Producing Escherichia coli (STEC) as Severe Human Pathogens

Journal of Food Protection

EXECUTIVE SUMMARY

The National Advisory Committee on Microbiological Criteria for Foods (NACMCF or Committee) was asked to report on (i) what is currently known about virulence and pathogenicity of Shiga toxin–producing Escherichia coli (STEC) and how they cause illness in humans; (ii) what methods are available to detect STEC and their specific virulence factors; and most importantly (iii) how to rapidly identify foodborne STEC that are most likely to cause serious human disease. Individual working groups were developed to address the charge questions, as well as to identify gaps and give recommendations for additional data or research needs. A complete list of Committee recommendations is in Chapter 4.

Research – Evaluation of Inactivating Norovirus, Hepatitis A, and Listeria monocytogenes on Raspberries by Sanitizer Spray

Journal of Food Protection

ABSTRACT

Reducing the risk of contamination with foodborne pathogens is paramount in maintaining safety of produce. The raspberry industry uses chlorine spray as a control measure before conveying freshly picked red raspberries into individually quick frozen units. However, the efficacy of sanitizer spray treatment to inactivate norovirus, hepatitis A virus (HAV), and Listeria monocytogenes on raspberries has not been characterized. In this study, a laboratory-scale spray bar device was fabricated to simulate industrial settings. Fresh raspberries were spot inoculated with murine norovirus (MNV, a norovirus surrogate), HAV, or L. monocytogenes and sprayed with 50 ppm of chlorine or 80 ppm of peroxyacetic acid (PAA). Surviving pathogens were enumerated after spray or postspray frozen storage at −20°C for 1 and 24 h. Chlorine and PAA spray treatments reduced MNV and L. monocytogenes from raspberries by 0.2 and 0.6 log but had no effect on HAV. During frozen storage after spray treatment, the residual PAA on the fruit surfaces further reduced MNV and L. monocytogenes, achieving a total reduction of approximately 0.6 and 3.0 log, respectively. HAV levels were not affected by frozen storage after PAA or chlorine spray treatment. The findings were supported by the sanitizer decay results showing that PAA decayed more slowly than active chlorine on raspberry surfaces. Submerging washes conducted as comparisons showed higher reduction of pathogens from raspberry surfaces than similar respective sanitizer spray treatments. The results suggest that PAA could contribute to raspberry postharvest sanitation, aiding in risk reduction of pathogen contamination prior to entering an individually quick frozen unit.

Research – Growth of Salmonella and Other Foodborne Pathogens on Inoculated Inshell Pistachios during Simulated Delays between Hulling and Drying

Journal of Food Protection

ABSTRACT

During harvest, pistachios are hulled, separated in water into floater and sinker streams (in large part on the basis of nut density), and then dried before storage. Higher prevalence and levels of Salmonella were previously observed in floater pistachios, but contributing factors are unclear. To examine the behavior of pathogens on hulled pistachios during simulated drying delays, floater and sinker pistachios collected from commercial processors were inoculated at 1 or 3 log CFU/g with cocktails of Salmonella and in some cases Escherichia coli O157:H7 or Listeria monocytogenes and incubated for up to 30 h at 37°C and 90% relative humidity. Populations were measured by plating onto tryptic soy agar and appropriate selective agars. In most cases, no significant growth (P > 0.05) of Salmonella was observed in the first 3 h after inoculation in hulled floaters and sinkers. Growth of Salmonella was greater on floater pistachios than on corresponding sinkers and on floater pistachios with ≥25% hull adhering to the shell surface than on corresponding floaters with <25% adhering hull. Maximum Salmonella populations (2 to 7 log CFU/g) were ∼2-log higher on floaters than on corresponding sinkers. The growth of E. coliO157:H7 and Salmonella on hulled pistachios was similar, but a longer lag time (approximately 11 h) and significantly lower maximum populations (4 versus 5 to 6 log CFU/g; P < 0.05) were predicted for L. monocytogenes. Significant growth of pathogens on hulled pistachios is possible when delays between hulling and drying are longer than 3 h, and pathogen growth is enhanced in the presence of adhering hull material.

HIGHLIGHTS
  • Foodborne pathogens multiplied on undried inshell pistachios.

  • Pathogen growth was greater when hull material was present.

  • Drying delays of >3 h led to significant increases in pathogen populations.

  • Managing drying delays will reduce the risk for growth of foodborne pathogens.