Food Safety Talk 183: Raw Raw Raw Almonds

Image from PIRO4D at Pixabay

Don and Ben are joined by longtime friend and colleague, podcast downloader (and sometimes listener) Linda Harris. The three nerds talk about other podcasts, Kardashian indices, Erdos numbers, berries, and the long and progressive food safety story of raw almonds. The almond story touches on what should happen when an industry has a major outbreak, how working with extension and research academics can lead to solutions and ripples of managing food safety risks.

You can download Food Safety Talk 183 here or at iTunes.

Show notes so you can follow along at home:

Irradiation of almonds to control Salmonella

Two outbreaks of salmonellosis were linked to the consumption of raw almonds from California in 2001 and 2004.

almonds-cssrAs a result, federal regulations were developed, which mandate that all almonds grown in California must be treated with a process that results in a 4-log reduction of Salmonella. Because most of the technologies approved to treat almonds rely on the application of heat to control Salmonella, an evaluation of alternative technologies for inactivating heat-resistant Salmonella Enteritidis PT30 and Salmonella Senftenberg 775W was needed.

In this study, almonds were inoculated with Salmonella Enteritidis PT30 and Salmonella Senftenberg 775W and then treated with an electron beam (e-beam) or by blanching or oil roasting. The irradiation D 10-values for Salmonella Enteritidis PT30 and Salmonella Senftenberg 775W treated with e-beam were 0.90 and 0.72 kGy, respectively. For heat treatments, thermal D 10-values for Salmonella Enteritidis PT30 and Salmonella Senftenberg 775W strains were 15.6 and 12.4 s, respectively, when subjected to blanching at 88°C and 13.2 and 10.9 s, respectively, when roasted in oil at 127 ± 2°C.

No significant differences in irradiation and thermal treatment results were observed between Salmonella Enteritidis PT30 and Salmonella Senftenberg 775W (P > 0.05), indicating that e-beam irradiation may be a feasible technology for reducing Salmonella in almonds. However, the sensory changes resulting from irradiating at the doses used in this study must be evaluated before e-beam irradiation can be used as a nonthermal alternative for decontamination of almonds.

Efficacy of Traditional Almond Decontamination Treatments and Electron Beam Irradiation against Heat-Resistant Salmonella Strains

Journal of Food Protection, Number 3, March 2016, Pages 369-375, DOI:

P. Cuervo, L. M. Lucia, and A. Castillo


Pistachios following the way of the almond industry: developing validated pasteurization interventions

Nuts and other low moisture foods can be a source of Salmonella. That’s not new. But many folks in the low-moisture foods industries are now conducting risk assessments and validating interventions (like pasteurization) to keep the Salmonella out of the hands of bar patrons everywhere.

The almond industry led the way about a decade ago. The peanut industry, in the wake of two outbreaks followed. According to Growing Produce, the pistachio industry is working with friend of barfblog (and known to her close friends as at the almond queen) Linda Harris and Michigan State’s Bradley Marks on some validation work.pistachios

“At this point in our world, Salmonella is a hazard that is reasonably likely to possibly occur in low-moisture products like nuts. It’s happened before, so we have to assume it’s possible it could happen again,” Marks says. “That being the case, the proposed rules of FSMA require that the processor have a validated process that they can document that they’ve shown achieves the food safety objective.”

Marks and his colleagues are currently working on lab-scale research to evaluate the effects of the pasteurization process and product conditions on the resistance of Salmonella to heating. “We’re doing some mathematical modeling so we can understand the rate of Salmonella activation as a function of temperature, time, and conditions of the product or the process itself,” Marks says.

The second part of the project will involve similar work on a pilot scale. “We have a system where we can inoculate pistachios with Salmonella and subject them to a process like a flatbed roaster,” Marks says. “So we are looking at validating that our prediction of the inactivation of Salmonella is correct, and that a non-pathogenic surrogate (Enterococcus faecium) also is reliable as a means to validate the process.”

Marks is working closely with Linda Harris, co-principal investigator for the Western Center for Food Safety at the University of California, Davis, to develop guidelines and on-site workshop training for pistachio processors. The guidelines and training will focus on what needs to be measured and documented to meet the FSMA requirements.

Scientology for food; biodynamic almonds recalled for Salmonella

Biodynamic agriculture could be batshit crazy, what with the filling and burying of shit in cow horns.

But I’m not judging.

I am judging why a major Australian retailer would carry biodynamic almonds.

That’s crazy.

Woolworths Ltd has recalled Macro Wholefoods Market Organic Biodynamic Almonds nationally from Woolworths Supermarkets, Safeway, Food for Less, Flemings Supermarkets and Thomas Dux Grocers due to Salmonella contamination. Food contaminated with Salmonella may cause illness if consumed. Consumers should not eat this product and should return it to the place of purchase for a full refund. Any consumers concerned about their health should seek medical advice.