3.2.1. Bean size and uniformity

The weight of a cocoa bean should be at least 1.0g. Smaller beans have higher shell contents and, consequently, less nib, which may also have a lower percentage of fat. Small beans can be used (provided the parcel is homogeneous) but require adjustment to factory processes which is inconvenient and costly - causing a reduction in plant throughput. 

For this reason beans should be sold on the basis of a bean size classification, e.g. less than 100 beans per 100g, 100 to 110g, more than 120/100g etc (See Part II for further information on bean count). 

Manufacturers also require beans to be reasonably uniform in size because it is difficult to achieve effective bean cleaning in a parcel containing beans that are very variable in size. A general guideline is that no more than 12% of the beans should be outside the range of plus or minus one third of the average weight. 

This distribution applies to most cocoa as harvested, but not after small beans have been blended into a parcel in order to bring the average bean size closer to the limit of a particular size classification. 

However, applying and checking this standard formally is time consuming unless specialised equipment is to hand. Informal judgement by eye on a given weight of a random sample of whole beans is usually sufficient; for example, if 72 of the smallest-looking beans taken from 600 grams of beans consisting of 600 beans collectively weigh less than 48 grams; there is a problem.  By the same manner, if 72 of the largest-looking beans weigh more than 96 grams there is also the likelihood of blending. 

Note that ‘a single whole bean’ here does not include flat beans as they, by definition, have no nib and are therefore not whole beans. Such a test is unusual; the better option is to rely on the grower and to use traceability of the parcel to ensure uniformity.