Updated January 2, 2019
To ensure that data accepted into the Crop Composition Database are of high quality, certain criteria must be met. Representative plant samples must be obtained from field-grown crops in which the production locations and dates are known. Sample collection must be done in a way that maintains the integrity of the sample throughout the analytical process, and analytical methods used in the generation of the data must be validated and in the published literature. Please use the checklist below to indicate that your data adhere to the criteria regarding production, sample collection, sample analysis, data, auditing, and archiving and submission of data.
Production of Samples Criteria:
The following information must be known about the field trials in which the samples were produced:
- Location of the trial plot, including region and country, must be reported.
- Year of sample collection or harvest year must be reported.
- Date of planting (transplanting for fruit tree crops) must be documented and retained, although not submitted as part of the data.
- All samples must be collected from non-transgenic plants.
- Reporting of seed vendor and variety are optional.
Sample Collection Criteria:
- Each sample must be a composite sample collected from representative plants of a single plot, part of a designed field trial at a single location. If a sample is collected from a large production-style plot, (e.g., bulk grain production), appropriate methods must be used to ensure the sample collected is representative of the plot.
- Developmental stage of the plant at the time of sample collection must be documented and retained, although not submitted as part of the data.
- Whole grain or seed samples may be stored at ambient temperature until analyzed. Fresh fruit or kernel samples (e.g., apples, sweet corn, etc.) must have been stored frozen until analyzed. Any sample that is milled or ground must be milled in a frozen state and stored frozen until analyzed.
- Forage samples that were oven dried upon harvest prior to analysis must be identified as such.
- The complete chain of custody of the samples from harvest to analysis, and the storage conditions of the sample, must be known, but are not submitted as part of the data.
- The method of pollination for production of seed/fruit samples must be documented and retained, although not submitted as part of the data.
Sample Analysis Criteria:
- Samples must be analyzed within 12 months of collection, and must have been kept under the storage conditions mentioned above.
- Analyses should be conducted by accredited/certified laboratories, or laboratories experienced with the specific analytical methodology.
- Analyses must be conducted using validated methods using certified or historically verified standards. Standard compendial methods such as those published by Association of Analytical Communities (AOAC), American Association of Cereal Chemists (AACC), American Oil Chemists' Society (AOCS), International Organization for Standardization (ISO), and United States Pharmacopeia (USP) are considered to be validated. A validated method may also be one that is published and has undergone sufficient testing to ensure the quality, reliability, and consistency of results through the determination of specificity, accuracy, precision, linearity, and robustness.
- The Crop Composition Database maintains an established internal database of method codes representing methods that have been confirmed as valid for one or more specified analytes. All individual data points submitted to the database must correspond to an established method code.
- Results for each analyte must be reported in the same chemical form in order to ensure that meaningful comparison can be made (e.g. thiamine vs. thiamine hydrochloride). Values for chemical forms of an analyte not already included in the database may be considered for inclusion in later versions of the database but must be defined as a separate analyte. The analyte name must be reported in the Crop Composition Database standardized format.
- A moisture value must be reported for each sample.
Data Criteria:
- Each data point submitted to the database must be derived from analysis of a single composite sample. Data based on averaging of values from multiple samples will not be accepted. Furthermore, no more than one single analytical result per composite sample must be submitted for a given analyte.
- Unit of measure must be reported. Whenever possible, data should be submitted in a unit of measure currently in use for the corresponding crop and analyte. Although the database is designed to perform unit conversion, unusual units of measure may not be accepted.
- The data submitter must retain data and corresponding records after submission to the database, including any sample-related information not reported in the database.
- Prior to publication, Agriculture & Food Systems Institute (AFSI) will perform an outlier test on all submitted data. Any potential outliers must be evaluated and verified by the data provider.
Auditing and Archiving of the Data:
- The submitter agrees to archive the raw data from which the submitted data were derived.
- AFSI reserves the right to confidentially audit datasets at the originating organization (at AFSI's expense) to ensure that the requisite raw data are available. If a data point is questioned and the validity of the data cannot be confirmed, AFSI reserves the right to delete the data point from the database.
Submission of Data:
- Institutions and organizations interested in submitting data to the database may contact the database curator (ccdb@foodsystems.org) to determine if their data meets the criteria for submission.
- Data must be submitted as comma-delimited in a defined format, available upon request. The following parameters must be included in each data submission unless noted as optional below:
- Unique study ID (self-assigned)
- Unique sample ID (self-assigned)
- Analyte (note: moisture is required for each sample)
- Analytical value
- Unit of measure
- Analytical method code (defined by Crop Composition Database)
- Crop
- Tissue type
- Harvest year
- Country of sample origin
- Region (state or province) of sample origin
- Seed vendor (optional; seed vendor information is available to database end-users only in summary or tabular reports and is not accessible for individual data points)
- Seed variety (optional; seed variety information is available to database end-users only in summary or tabular reports and is not accessible for individual data points)
- Biotech data status (note: currently only non-transgenic data will be published)
- Forage oven-dried status
- Prior to submission, the data provider must perform quality control checks on the analytical data.
For further information about the database and data submission, contact ccdb@foodsystems.org.