Reduction of L. monocytogenes due to maceration of fish fillets with gravlax curing agents

The function sfMaceration() describes the effect of macerating the fish fillets with lemon juice, salt, sugar, black pepper and dill during 72 hours at 4 ºC. Lot-specific log10 reduction values are sampled from a normal distribution.

Usage

sfMaceration(
  data = list(),
  nLots = NULL,
  sizeLot = NULL,
  rGravadMean = 0.7,
  rGravadSd = 0.283
)

Arguments

data

See Lot2LotGen() function.

nLots

Number of lots sampled or size of the Monte Carlo simulation (scalar).

sizeLot

Number of units or portions produced in a lot (scalar).

rGravadMean

(log10) mean of the normal distribution about the log10 reduction in L. monocytogenes in brine-injected fish fillets due to smoking and 18-24-h maturation (scalar).

rGravadSd

(log10) standard deviation of the normal distribution about the log10 reduction in L. monocytogenes in brine-injected fish fillets due to smoking and 18-24-h maturation (scalar).

Value

A list of two elements:

N

(CFU) A matrix of size nLots lots by sizeLot units containing the numbers of L. monocytogenes in fish fillets after macerating with gravlax ingredients

pSurvSmoking

Probability of a microbial cell to survive the maceration treatment (vector).

Note

The suggested parameters rGravadMean=0.7 and rGravadSd=0.283 defining the normal distribution about the variability in the log10 reduction in L. monocytogenes in fish with gravlax ingredients were obtained combining the results from Lopes et al. (2023) and Neunlist et al. (2005) .

References

Lopes SM, da Silva DC, Tondo EC (2023). “Survival of Listeria monocytogenes in Gravlax Salmon (Salmo salar) recipe.” International Journal of Gastronomy and Food Science, 34, 100836. ISSN 1878-450X, doi:10.1016/j.ijgfs.2023.100836 , https://www.sciencedirect.com/science/article/pii/S1878450X23001786. Wolodzko T (2020). extraDistr: Additional Univariate and Multivariate Distributions. R package version 1.9.1, https://CRAN.R-project.org/package=extraDistr. Neunlist MR, Ralazamahaleo M, Cappelier J, Besnard V, Federighi M, Leroi F (2005). “Effect of salting and cold-smoking process on the culturability, viability, and virulence of Listeria monocytogenes strain Scott A.” Journal of food protection, 68, 85-91. Team RC (2022). R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/.

Author

Ursula Gonzales-Barron ubarron@ipb.pt

Examples

rGravadMean=0.7
rGravadSd=0.283
dat <- Lot2LotGen(
                  nLots = 50,
                  sizeLot = 100,
                  unitSize = 500,
                  betaAlpha = 0.5112,
                  betaBeta = 9.959,
                  C0MeanLog = 1.023,
                  C0SdLog = 0.3267,
                  propVarInter = 0.7
                  )
gravadfish <- sfMaceration(dat, 
                           rGravadMean=rGravadMean,
                           rGravadSd=rGravadSd)
hist(gravadfish$N)