Gum Arabic Processing
There is a basic gum cleaning process before sale. The purpose of this cleaning process is to remove sands, barks and any strange material. The process includes methods such as crude sieving, manual selection, manual grading and picking of bark, etc.
The subsequent phase involves grading into the following grades/qualities of Sudanese gum on the basis of color, clarity and cleanliness:
- Handpicked selected or HPS (selected sorts) – This ensure a pale uniform color and freedom from extraneous material.
- Cleaned and sifted (cleaned sifted sort) – This is what is left after the handpicked selected is taken away and the siftings are removed.
- Cleaned (cleaned amber sorts) – This is the standard grade used throughout the world. Here, siftings are still present, but the dust is removed.
- Siftings – This is the material originated from the production of cleaned and sifted. It comprises of fine particles of gum with a proportion of fine bark and sand.
- Dust – This is produced from the cleaning process. It comprises of very fine particles of gum, sand and clay/earth.
- Kibbling and Sizing
Different grading systems are used in other exporting countries, and although Sudanese production is more tightly controlled, good quality Nigerian or Chadian grades from reputable dealers can match Sudanese material.
Gum Arabic Being Processed At Our Facilities
The harvest is timed according to the ripeness of the seed. The wet red fleshy calyces are harvested after the flower has dropped but before the seed pod has dried and opened. All harvesting is done by hand. Special care must be taken during harvesting operation to avoid contamination by extraneous material. At no time should the calyx come in contact with the ground or other dirt surfaces. Clean bags or containers should be used to transport from the field to the drying location.
Only ripe calyces are harvested with clippers leaving the stalks and immature calyces to ripen in the field. The field is harvested approximately every ten days until the end of the growing season. The calyx is separated from the seed pod by hand, or by pushing a sharp edged metal tool through the fleshy tissue of the calyx separating it from the seed pod.
A clean sheet of plastic placed on the ground can also be used with the hibiscus spread thinly on top. Spreading the calyces on screens or frames would improve ventilation further and reduce drying time. Such frames could also be stacked or hung in a well ventilated building. Drying the calyces in forced air dryers would be costly and is rarely done. If heated drying methods are used, care must be taken so that the temperature does not exceed 43oC.
The hibiscus after drying is hand cleaned and shifted to export standards.
The Sesame pods once ripe are gathered and allowed to dry. Once dry the pods gently shaken to allow the Sesame to fall on to a clean sheet of plastic. The Sesame is collected then packed into bags natural.
The Sesame is cleaned mechanically through pre- cleaners and de- stoners with the dust being sucked out through air ducts and collected in cyclones. The cleaned product is ready for export.