EVALUATION OF DEGREASERS AS BRINE CURING ADDITIVES

The length of time needed for brine curing of raw hides and skins, a minimum of 18 h, is a time-consuming process. In this paper we initially report the results of an investigation of the stratigraphic distribution of sodium chloride and water in fleshed hides cured for varying intervals of time. We demonstrated that salt entered the hide mainly from the flesh side. Water, on the other hand, was withdrawn from both sides of the hide; the epidermis acted as a semipermeable membrane. Three commercial degreasers as well as a glycolipid surfactant (sophorolipid) were tested as brine curing additives and their efficiency evaluated according to the moisture, salt, salt saturation and fat content levels in the brine-cured hide. One of the commercial degreasers, when used at 0.5% w/w, significantly removed fat from the hide as well as enhanced the uptake of salt. The sophorolipid also was an effective degreasing agent, decreasing the fat content of the brine-cured hide and, if used in excess, significantly increasing the uptake of salt. The data presented here confirmed that the usage of an appropriate degreasing agent in the brine is a suitable option for reducing the turn-around times in raceways and thus creating additional curing capacity.