Why and How to Measure Food Loss and Waste

Records - Why and How to Measure Food Loss and Waste

Records are collections of data that have been gathered and saved. There are numerous types of records, such as waste transfer receipts or warehouse records. Although these data may have been gathered for purposes other than FLW quantification, they can often be repurposed to help gain an understanding of FLW levels within a facility.

When to Use Records

Records are valuable for FLW quantification where data related to FLW is routinely being collected. For this reason, records are most likely to be useful in the manufacturing, retail and food service sectors, since proprietors frequently collect and track data relating to purchasing, food inventory and waste management.

Using existing records can be more cost-effective than undertaking new measurements, since the records are already being gathered for other purposes. Additionally, because resources like the Provision Coalition Food Loss and Waste Toolkit allow users to input their existing records to estimate FLW levels, this can be a simple and straightforward method. However, since the data have not been gathered expressly for FLW quantification, they may be unclear or in a form not useful for the project. This can lead to less accurate data and may require additional time and effort in adjusting the data to fit the needs of the measurement exercise.

The causes of food loss and waste can be difficult to discern from records, since the factors leading to the waste are generally not recorded. For these reasons, records are often used to supplement another FLW quantification method rather than as a primary method.

A summary of the strengths and limitations of records is shown in Table A15.

Table A15. Factors to Consider when Using Records to Quantify FLW

Strengths Limitations / Points to Consider
  • Relatively cost-effective, because records have already been gathered for other purposes
  • Can provide high coverage of material flow to quantify
  • Suitable for initial investigation into food waste to help build internal business case, and can continue as supplement to other quantification methods into the future
  • Accuracy depends on method used for quantification
  • May be hard to obtain a method for quantification depending on the type of record used
  • May not have the desired granularity of data (e.g., types of wasted food)
  • Unlikely to include information on root causes (i.e., reasons why food is thrown away)

Source: Authors.

How to Use Records to Quantify FLW

This section gives four steps to use existing records to gather information about FLW.

Step 1: Identify the records available

A variety of records may be available to assist with FLW quantification.

  • Purchasing information: contains data relating to the amount and types of food being brought in by the entity looking to quantify its FLW.
  • Waste transfer receipts: contains data relating to the amount of waste being transported away from a facility. It may also contain information about where the waste is being disposed of (i.e., anaerobic digestion, landfill). In some cases, organic waste is separated from inorganic waste prior to waste transfer. If organic waste and inorganic waste are combined, the amount of organic waste will need to be estimated.
  • Existing waste-reduction measurements: Many larger-sized companies undertake waste reduction or efficiency measurement methodology, such as Six Sigma (FUSIONS 2016). These records may be useful when quantifying FLW.
  • Donation receipts: If the facility or business in question has donated food to charities or food banks, it may retain receipts to track the types and amounts of food donated. Although this food is not considered to be FLW since it remains in the human food supply chain, many businesses still find value in tracking the amount of food being donated.
  • Records of chemical oxygen demand (COD) in sewage: Biochemical oxygen demand (BOD) is the amount of oxygen that bacteria take from water when they oxidize organic matter (Hach et al. 1997). Because BOD tests tend to be costly, a chemical oxygen demand (COD) test, which is the total measurement of all chemicals in the water that can be oxidized, is generally used as a proxy to measure for BOD. The sewage treatment company used by the company conducting the FLW quantification may possess COD data that can be used to estimate the amount of organic matter being sent down the drain.

These examples are emblematic of the type of records that will be useful for an FLW quantification effort.

Step 2: Assess the relevance of the records

Assess how relevant the selected records are for the needs of the FLW quantification project being undertaken. First, determine if they are in line with the scope of the inventory, as discussed in the “Setting Your Scope” module. Next, consider the reliability of the records by examining the following aspects (FLW Protocol 2016):

  • the method used to compile the records;
  • the measurement devices used;
  • the transcription of the measurement or approximation into the record; and
  • any assumptions or conversion factors used.

Some or all of these items may be missing, which will contribute to a less accurate figure for FLW quantification.

Step 3: Acquire the records

Records can be grouped broadly into two categories: internal and external.

Internal records are already possessed by the entity doing the FLW measurement, and therefore are easier to access. For these records the primary challenge will be identifying who is producing them and requesting the records. Inform the record-holder why the records are needed, which will help the record-holder to understand why the records are important and will build awareness about FLW measurement and reduction within the company or organization.

If the records belong to an external party, such as a waste management company, it may be more difficult to obtain the relevant data. However, the following strategies may be useful (FLW Protocol 2016).

  • Explain how the records will be used and the societal and economic benefits of quantifying FLW.
  • Ensure that the records will be used confidentially.
  • Offer an incentive or monetary compensation for response.
  • Provide clear direction for the respondent to make the process as easy as possible.

Step 4: Prepare and analyze the data

Next the data in the records must be standardized and collated. The simplest method for doing this is by entering the data into an electronic spreadsheet. If the records contain direct FLW data, this process may be as simple as adding up the relevant values. If the records provide data on a mixed waste stream, applying an FLW factor (e.g., how much of the waste is FLW) to the data will be necessary. If the data do not directly provide this factor, it can be obtained by performing a waste composition analysis.

Common Data Challenges when Using Records

Inconsistencies between data sources. When using records drawn from a variety of sources, it is inevitable that methodologies, terminologies and units of data will differ, leading to confusion when the data are combined. One way to avoid this problem is to provide the record-holder with the definitions being used for terms such as “food waste” to develop a common understanding.

Data gaps or insufficient information. Records will not always provide all the data necessary for a complete FLW quantification. In these instances, a series of steps can be taken. First, determine if the records provide enough data to formulate a plan for FLW reduction. If there is, proceed with developing a plan but also inform the record-holder of the gaps that exist in hopes that the missing data can be collected over time. If the gaps are too significant to proceed, use another FLW quantification method. Consult the module relevant to your sector to determine which methods are most appropriate.

Insufficient information on causes of FLW. Most records are of numerical data and do not capture information on attitudes or activities that contributed to the waste, making it difficult to ascertain the causes of FLW. Thus, records may need to be augmented by a survey or interview process to obtain information on why FLW was being generated. Additional guidance on this can be found in the Surveys module.

Additional Resources for Using Records

FLW Protocol. 2016. Chapter 5. “Records.” In Guidance on FLW quantification methods. <http://flwprotocol.org/wp-content/uploads/2016/06/FLW_Guidance_Chapter5_Records.pdf>.

FUSIONS. 2016. Food waste quantification manual to monitor food waste amounts and progression. <www.eu-fusions.org/phocadownload/Publications/Food%20waste%20quantification%20manual%20to%20monitor%20food%20waste%20amounts%20and%20progression.pdf>. (See especially the sections “Identify and review existing data relating to food waste” for each sector.)