‘Rusty’ thumbtack found inside NZ blueberry dessert

As the needle-in-produce saga in Australia subsides, it has spread to New Zealand, probably by dim-witted copycats.

Zoe Hunter of the New Zealand Herald reports a batch of blueberries has been removed from supermarket shelves after a Tauranga man believes he found a “rusty” thumbtack inside the small fruit.

The man, who would only be named as Mr Osborne, was celebrating his wife’s birthday at his mother-in-law’s home last night and took the last mouthful of his dessert when he bit into a thumbtack.

“Luckily I bit into it sideways and spat out the tack,” he said.

He believes the thumbtack was inside one of the blueberries that his mother-in-law used in her cake recipe.

“It seems pretty well thought out because when I pushed it into the side of the blueberry you couldn’t see it,” he said. “It was rusty and slightly bent.”

The man had learned blueberries were a good snack for dogs and he and his wife had just got a new puppy.

“Lucky I did not give it to my dog,” he said.

After the incident, Osborne put the blueberry and thumbtack inside a ziplock bag and notified supermarket staff, who he said had handled the complaint well.

Osborne said his mother-in-law had bought the punnet of blueberries from Pak’nSave in Pāpāmoa on January 21.

He had posted his find on Facebook to warn people about checking their fruit thoroughly before eating it.

A Foodstuffs spokesperson said the company had been notified about the incident and an investigation was under way.

“The batch has been pulled from store shelves and we are going through our stringent investigative process,” she said.

“The outcome of the investigation will be referred to the authorities for their review and support.”

The find was the latest in a series of sharp objects finds in produce around New Zealand.

Foreign objects in fruit and vege in 2018:
December: Pin found in strawberry bought at Pak’nSave Cameron Rd
November: Needle found in a capsicum bought at Countdown Bureta 
November: Needle found inside a punnet of strawberries purchased at a supermarket in the South Island in November
September: Three needles found in three strawberries in one imported punnet of Australian Choice brand strawberries at Countdown St Lukes in Auckland

New Zealand Food Safety advice: 
If you see something out of the ordinary, please take it to your retailer or give us a call on 0800 00 83 33.

Blueberries and bugs: Can UV light help?

Ultraviolet light (UV) has antimicrobial effects, but the shadowing effect has limited its application.

blueberriesIn this study, a novel setup using UV processing in agitated water was developed to inactivate Escherichia coli O157:H7 and Salmonella on blueberries.

Blueberries were dip- or spot-inoculated with E. coli or Salmonella. Blueberries inoculated with E. coli were treated for 2 to 10 min with UV directly (dry UV) or immersed in agitated water during UV treatment (wet UV). E. coli was most easily killed on spot-inoculated blueberries with a 5.2-log reduction after 10-min wet UV treatment. Dip-inoculated blueberries were the most difficult to be decontaminated with only 1.6-log reduction after 10-min wet UV treatment.

Wet UV treatment generally showed higher efficacies than dry UV treatment, achieving an average of 1.4 log more reduction for spot-inoculated blueberries. For dip-inoculated blueberries, chlorine washing and UV treatments were less effective, achieving <2 log reductions of E. coli. Thus, the efficacy of combinations of wet UV with sodium dodecyl sulfate (SDS), levulinic acid, or chlorine was evaluated. Inoculated blueberries were UV-treated while being immersed in agitated water containing 100 ppm SDS, 0.5% levulinic acid or 10 ppm chlorine.

The 3 chemicals did not significantly enhance the wet UV treatment. Findings of this study suggest that UV treatment could be used as an alternative to chlorine washing for blueberries and potentially for other fresh produce.

Practical Application

A novel UV light system for decontamination of blueberries in water was developed and evaluated. Results demonstrated that the decontamination efficacy of this system was generally as effective as chlorine washing, indicating that it could potentially be used as an alternative to chlorine washing for blueberries and other fresh produce.

Inactivation of Escherichia coli O157:H7 and Salmonella enterica on blueberries in water using ultraviolet light

Journal of Food Science, 80: M1532–M1537

Liu, C., Huang, Y. and Chen, H.


Can chlorine dioxide improve the microbiological safety of frozen blueberries?

Blueberries are prone to microbial contamination, with growth of bacteria, yeasts and molds during bulk freezing negatively impacting quality and marketability. As a follow-up to our previous work, the combined impact of ClO2 gassing and freezing rate on the microbiological quality of frozen blueberries was examined.

blueberry.lugSixteen lugs of blueberries (∼9.1 kg/lug) were stacked inside a large plastic container at a commercial blueberry processing facility. In each of four trials, one container was exposed to ClO2 gas (4 ppm) using three 3-kg sachets while one ungassed container remained untarped. Before and after commercial processing, 50-g samples of gassed and ungassed blueberries were quantitatively examined for mesophilic aerobic bacteria (MAB), yeasts, and molds. After processing, additional 50-g samples were placed in a −20 °C freezer under different conditions where the berries reached a temperature of −3 °C after 3 h (quick-frozen), 2 days (intermediate-frozen) and 5 days (slow-frozen). Fruit was sampled periodically during 6 months of frozen storage at −20 °C. MAB yeast and mold populations decreased ∼2 and 1 log CFU/g, respectively, in ClO2-gassed and ungassed fruit, with MAB, yeast and mold populations increasing ∼1 log CFU/g during quick freezing to −3 °C and ∼2 log CFU/g during intermediate and slow freezing to −3 °C. Based on these findings, ClO2 gassing followed by quick freezing provides an effective means for meeting the current microbiological standards being imposed by buyers of frozen blueberries.

 Efficacy of chlorine dioxide gas and freezing rate on the microbiological quality of frozen blueberries


Lei Zhang, Zhinong Yan, Eric J. Hanson, Elliot T. Ryser

Food Control, Volume 47, January 2015, Pages 114–119, DOI: 10.1016/j.foodcont.2014.06.008


6 sickened; Salmonella-contaminated blueberries from Georgia in 2010 tracked down by Minn. health types using GTINs and shopper cards


In August 2010, the Minnesota Department of Agriculture and Minnesota Department of Health investigated an outbreak of six cases of Salmonella Newport infection occurring in northwestern Minnesota, which identified fresh blueberries as the cause. Initially, traditional traceback methods involving the blueberryreview of invoices and bills of lading were used to attempt to identify the source of the outbreak. When these methods failed, novel traceback methods were used. Specifically, supplier-specific 12-digit Global Trade Item Numbers (GTINs) and shopper-card information were used to identify a single blueberry grower linked to cases, corroborating the results of a case-control study in which consuming fresh blueberries was statistically associated with illness (5 of 5 cases versus 8 of 19 controls, matched odds ratio [MOR] undefined, P = 0.02). Consuming fresh blueberries from retailer A was also statistically associated with illness (3 of 3 cases versus 3 of 18 controls, MOR undefined, P = 0.03). Based on initially incomplete evidence in this investigation, the invoices pointed to wholesaler A and grower A, based on first-in-first-out product rotation. However, when point-of-sale data were analyzed and linked to shopper-card information, a common GTIN was identified. This information led to an on-site record evaluation at retailer A, and the discovery of additional records at this location documented the supply chain from grower B to wholesaler C to retailer A, shifting the focus of the investigation from grower A to grower B. This investigation demonstrates the emerging concepts of Critical Tracking Events (CTEs) and Key Data Elements (KDE) related to food product tracing. The use of these shopper-cased data and the event data that were queried by investigators demonstrates the potential utility of consciously designed CTEs and KDEs at critical points in the supply chain to better facilitate product tracing.

Use of Global Trade Item Numbers in the investigation of a Salmonella newport outbreak associated with blueberries in Minnesota, 2010

Journal of Food Protection®, Number 5, May 2013, pp. 744-918 , pp. 762-769(8)

Miller, Benjamin D.; Rigdon, Carrie E.; Robinson, Trisha J.; Hedberg, Craig; Smith, Kirk E.