Showing 3 results for Gelatin
A. Aberomand,
Volume 11, Issue 1 (4-2007)
Abstract
Gelatin as a proteineous component is important in the food, pharmaceutical, medical abd technical industeries. Gelatin is used in food industerials to prepare marmallads, jellies, confectioneries and ice cream. The main purpose of this research was to optimize the usage of cheap primary material, i.e. a lot of fishery wastes for extraction of gelatin and to decrease the importation gelatin from abroad that is usually prepared from pig skin and wastes of animal. This research was conducted in two stages. In the first stage, the effect of pH conditions( in alkaline and acidic conditions) and type of raw material (three raw material: fillet plant wastes, fish shark fish hoof) were evaluated on some best qualitative and quantitative Characteristics of gelatin( yield, purification value, color and odor and flavor). In second stage, the temperature effect( in 3 levels,70,75,80 degree of centigrade) and pH in 2 levels (6.5 and 6) were evaluated on the gelatin yield content. It should be mentioned that all of raw material were prepared from fishery factory of Booshehr. The results from first stage showed that using from alkaline condition and fishery wastes, the amount of gelatin will be maximum with pH=6.5, temperature=70 degree of centigrade. Also under the same conditions the best quality gelatin can be obtained.
S. H. Hosseiniparvar, J. Keramat, M. Kadivar,
Volume 11, Issue 40 (7-2007)
Abstract
This research was carried out to determine the optimum conditions for acidic extraction of gelatine from cattle bones. The effects of different treatments such as pH (1.8 to 2.6), temperature (60 to 80°C) and time (40 to 120minutes) on yield of extraction, gel strength, viscosity and absorption (420 nm) was measured. Coefficients of central composite rotatable design (CCRD) and regression surface response.... (RSREG) were used. The coefficients for yield, gel strength, viscosity and absorption were 0.990, 0.991, 0.998, 0.928, respectively. According to variance analysis of the data, there were significant differences between the effects of three variables (pH, temperature and time) on yield of extraction and viscosity, but no significant difference was observed between the effects of temperature and pH on gel strength and absorption, respectively. Comparisons of the averages of functional characteristics of acidic and commercial gelatin showed that viscosity and strength of acidic gelatin were higher than those of commercial one. The optimum conditions were found to be: pH=1.88, temp. 80°C and 118 min., to reach the highest yield and pH=1.88, temp. 60°C and 48 min. to get maximum strength, and pH=2.56, temp. 69°C and 118 min. to obtain the maximum viscosity and finally, pH=2.6, temp. 62°C and 48 min. for minimum absorption. Also, the results revealed that there were significant differences between trace elements content (Fe, Ca and Pb) of commercial and acidic gelatins. Although, acidic gelatin contained higher amount of the elements, but these amounts were still less than maximum values which are allowed to exist in gelatin. Amino acid compositions of both gelatins were almost identical.
A Farahnaki, A Dehghn, Gh Mesbahi, M Majzobi,
Volume 13, Issue 48 (7-2009)
Abstract
Salad dressing is a semisolid emulsion and a colloidal system with high consumer demand. Food polysaccharides (e.g starch) are used in the formulation of salad dressing to improve its physical properties and sensory attributes. In this research, 10% mixture of wheat or maize starches were used to produce pregelatinized starches by a double drum drier, followed by milling and sieving. The pregelatinized starches (10%) were applied in the formulation of a salad dressing instead of native starch. Viscosity (at 25 and 35◦C), Hunter color parameters of the samples were evaluated and compared. Pregelatinized starches were more effective in increasing viscosity of the samples compared to corresponding native starches, and the effect of maize starch was greater than wheat starch. Significant differences were recorded in terms of color parameters of the samples. Pregelatinized starch caused higher L values (lighter samples) while the native starch samples were creamy-light yellow. In general, it can be concluded that the pregelatinized starches had better functional properties in salad dressing compared to native starches, and the produced pregelatinized starches can be used instead of native starch in the formulation of salad dressing.
