A Review of Gelatin Source Authentication Methods <s> Chemisorption Method <s> The amount of time that actually elapsed during the solution mediated transformation of amorphous calcium phosphate into crystalline apatite was short and invariable. On the other hand, the time required to reach this period of rapid precipitate conversion was strongly dependent upon the exact solution environment. Amorphous calcium phosphate was more stable when formed from solutions high in pH, ionic strength, and viscosity, rich in Ca2+ relative to HPO42−, and low in initial supersaturation and temperature. The suspension lifetime of amorphous calcium phosphate was also sensitive to changes in dielectric constant. Amorphous calcium phosphate was also more stable in the presence of poly-l-glutamate, polyacrylate, phosvitin, casein, and large amounts of the protein-polysaccharides, or by the addition of small amounts of Mg2+, P2O74−, CO32− and F−. Macromolecule-calcium phosphate flotation reactions (inhibition of ready sedimentation) were found for the casein, poly-l-glutamate, polyacrylate, and poly-l-lysine molecules as well as for the protein-polysaccharide complex. <s> BIB001 </s> A Review of Gelatin Source Authentication Methods <s> Chemisorption Method <s> Our study on the effects of different gelatins on calcium phosphate precipitation demonstrated that bovine bone gelatin and porcine skin gelatin could be distinguished using a pH drop method. The induction time was more remarkably increased by the addition of bovine bone gelatin than in the case of porcine skin gelatin. The difference between these two gelatins was significant at the concentrations of 0.5 and 2.0 mg/ml. The effects on hydroxyapatite transformation were biphasic. Gelatins increased the value at a lower concentration, but they decreased it after reaching a peak concentration. The peak concentration was 0.5 mg/ml for bovine bone gelatin, but was 4.0 mg/ml for porcine skin gelatin. Two commercial gelatin products were studied. One had properties close to bovine gelatin, and the other had properties close to porcine gelatin. This simple method may be useful in analyzing the origin of gelatin products. <s> BIB002 </s> A Review of Gelatin Source Authentication Methods <s> Chemisorption Method <s> Gelatine is a collagen derivative obtained from bones and hides/skin mainly from bovine and pigs. As a consequence of the outbreak of bovine spongiform encephalopathy (BSE), the use of bovine gelatine in feed, food and pharmaceutical products has been restricted by regulatory authorities. However, no method was presently available for its specific detection. The large similarity in amino-acid sequences of collagens from different species make their immunochemical differentiation difficult when using polyclonal antibodies raised against the whole molecule [A. Venien, D. Levieux, J. Immunoassay Immunochem., in press]. To obtain bovine-specific antibodies, we immunized rabbits against putative species-specific sequences of the bovine collagen alpha 1(I) chain. Using these antibodies, an indirect ELISA was developed to allow a quick and easy differentiation between bovine and porcine gelatines. Moreover, a competitive indirect ELISA was found suitable to detect bovine gelatine in porcine gelatine purchased from laboratory chemicals suppliers down to a dilution of 2-4 parts per 1000 with CVs ranging from 5.7 to 7.7%. When testing mixtures of the largest possible range of industrial batches of bovine and porcine gelatines (skin/hides or bones origin, acid or alkaline processes, high or low Bloom) the detection limit was down to a dilution of 8 parts per 100 bovine gelatine in porcine gelatine. These ELISAs could be routinely used by pharmaceutical and food manufacturers to secure their supply chain. <s> BIB003
Chemisorption is an adsorption process in which an adsorbate is held on the surface of an adsorbent by chemical bonds. Collagen, gelatin, and agarose gels stimulate the formation of hydroxyapatite (HAP) from amorphous calcium phosphate (ACP) BIB001 . The difference in gelatin can result in their chemisorption behaviours. BIB002 investigated the possibility of authenticating gelatin sources (bovine bone or porcine skin) using chemisorption of ACP precipitate and promotion HAP formation. It was observed that both gelatins were ineffective on the rate of ACP formation and exhibited biphasic HAP transformation. Induction time from bovine bone gelatin differs from that of porcine gelatin and that the stimulatory effect of gelatinase hydrolysis of bovine bone gelatin on the rate of HAP transformation was eradicated. However, this method required further study on effect of different reaction conditions like temperature, pH and concentration. Also, this method will not be suitable to detect bovine and porcine gelatin in their mixture BIB003 .