Comparing moisture and protein analysis for Great Northern beans

Identify the form before comparing composition

Moisture and protein figures only make sense in context: first establish whether you are comparing whole dry Great Northern beans, cooked beans, or canned beans. These are not interchangeable samples. Cooking adds water to the beans, changing the amount of protein in a given weight of product even though the protein in the beans has not simply disappeared.

Canned beans add another distinction. A composition figure may describe the beans after draining, or the contents as packed with liquid. Those figures answer different questions. When comparing a reference value with a commercial analysis, match the bean preparation and whether packing liquid is included. Otherwise, the difference may reflect water or sample preparation rather than a meaningful difference in bean composition.

Moisture changes the denominator

Moisture is the portion of a sample made up of water. Protein reported on an as-received basis is expressed relative to the product’s total weight, including that water. Protein reported on a dry-matter basis excludes moisture from the denominator, making it easier to compare samples with different water content.

This distinction matters when comparing dry beans with cooked or canned beans. Added water increases product weight and lowers the protein percentage on an as-received basis. A dry-matter value can help separate that dilution effect from differences in the non-water portion of the sample. It does not, by itself, make unlike products comparable: form and preparation still need to match.

If moisture and as-received protein are reported for the same sample, protein can be converted to a dry-matter basis: divide the as-received protein percentage by the percentage of dry matter, then multiply by 100. Dry matter is 100 minus the moisture percentage. Use values from the same sample and keep the reported units and basis clear.

Protein analysis needs a stated basis

A protein percentage without its reporting basis is incomplete for purchasing decisions. Ask whether the result is as received or on a dry-matter basis, and whether it applies to whole dry beans, cooked beans, or a defined canned-bean sample. A number taken from a food-composition reference can be useful for general comparison, but it is not a specification for a particular commercial lot.

Reference data describe a defined food and preparation. A lot analysis describes a tested sample from a particular supply lot. They serve different purposes: reference data can support early formulation work, while a lot-specific analysis is the relevant evidence for comparing an offered product against a purchasing requirement. The actual report should identify the product tested and make the moisture and protein basis clear.

Make the sample and comparison meaningful

Analysis is only useful if the sample represents the product being evaluated. For dry beans, establish that the sample is whole dry beans rather than cooked or processed material. For canned beans, specify whether the beans are drained and how the sample is prepared. Include the sampling point or lot identification in the review so that the result is tied to the material under consideration.

When two results appear inconsistent, compare the product form, preparation, moisture basis, protein basis, and sample identity before treating the difference as a quality change. A reference table may use a different preparation or reporting convention than a supplier’s lot report. Aligning those details often explains why the values cannot be compared directly.

Turn the analysis into a sourcing requirement

For a useful comparison, write the requirement in complete terms: whole dry, cooked, or canned beans; the moisture measure and basis; and protein reported as received or on a dry-matter basis. If a target or acceptance limit is needed, set it for the intended product and application rather than borrowing a value from a reference entry for a different form.

Once the form and analytical basis are defined, the Great Northern beans page is the natural next step for sourcing. Use the same terms when requesting a quote and reviewing a lot analysis, so the offered beans and the figures being compared refer to the same product.

Common questions.