This function retrieves FEMA (Flavor and Extract Manufacturers Association)
flavor profile information for a list of CAS Registry Numbers (CASRN) from
the PubChem database using the webchem package.
Arguments
- casrn
A vector of CAS Registry Numbers (CASRN) as atomic vectors.
- verbose
A logical value indicating whether to print detailed messages. Default is TRUE.
- delay
A numeric value indicating the delay (in seconds) between API requests. This controls the time between successive PubChem queries. Default is 0. See Details for more info.
Value
A data frame containing the FEMA flavor profile information for each CASRN. If no information is found for a particular CASRN, the output will include a row indicating this.
Details
The function performs two queries to PubChem:
The first query retrieves the PubChem Compound Identifier (CID) for each IUPAC name.
The second query retrieves additional information using the obtained CIDs. In cases of multiple rapid successive requests, the PubChem server may deny access. Introducing a delay between requests (using the
delayparameter) can help prevent this issue.
Examples
# \donttest{
extr_pubchem_fema(c("83-67-0", "1490-04-6"))
#> ℹ Checking Internet Connection...
#> ℹ Internet connection OK...
#> Querying 83-67-0.
#> OK (HTTP 200).
#>
#> Querying 5429.
#> Not Found (HTTP 404).
#>
#> Warning: FEMA Flavor Profile for 83-67-0 not found!
#> Querying 1490-04-6.
#> OK (HTTP 200).
#>
#> Querying 1254.
#> OK (HTTP 200).
#>
#> cid casrn IUPAC_name result
#> 1 5429 83-67-0 Theobromine <NA>
#> 2 1254 1490-04-6 Menthol Mint, Cool
#> source_name source_id
#> 1 <NA> <NA>
#> 2 Flavor and Extract Manufacturers Association (FEMA) 2665
#> other query
#> 1 FEMA Flavor Profile info not found 83-67-0
#> 2 <NA> 1490-04-6
# }