猪皮明胶提取过程中的超高压预处理工艺优化

Optimization of pretreatment by ultra-high pressure during production of gelatin from pig-skin

传统的酸碱法预处理明胶的生产工艺中存在生产周期长、酸碱产生的污染严重等问题,探索用超高压预处理的新工艺,以期改进明胶传统生产工艺,建立清洁高效的方法。以新鲜猪皮为原料,以提取率和凝胶强度为评价指标,以不进行预处理、传统酸处理为对照,研究比较了添加不同传压介质的超高压预处理对猪皮提胶效果的影响,从而选出效果较优的超高压预处理方法,进一步对超高压压力、超高压时间、酸质量分数等因素进行优化研究。结果显示,超高压有助于提高明胶提取率和凝胶强度,在超高压处理组中以酸/超高压组的提胶效果最优,较优的提胶工艺条件为超高压压力250MPa、超高压时间10min、HCl质量分数0.75%。在此条件下,猪皮明胶提取率可达88.62%,凝胶强度可达384.43g。SDS-PAGE电泳分析结果表明酸/超高压组明胶的α、β、γ等亚基组分含量较高,这可能是其高凝胶强度的原因所在。研究结果可为超高压技术在明胶制备中的应用乃至明胶清洁生产工艺的建立提供技术参考。

There are many problems such as long production period and serious pollution issued from acid and alkali existing in the production process of gelatin by traditional acid or/and alkali-base pretreatment method. The new pretreatment method using the ultra-high pressure （UHP） technology was investigated in this study to improve the traditional production process of gelatin and establish a clean and efficient preparation method. The effects of UHP pretreatment to the yield and gel strength of gelatin from pig-skin using different transmitting media were studied by comparison with controls treated by non-pretreatment and acid. The optimal UHP pretreatment method was selected and some factors such as pressure, time of UHP and concentration of acid were optimized further for the gelatin extraction. The results show that UHP pretreatment can improve the extraction yield and gel strength of gelatin. The best effect was got by combined pretreatment with UHP and acid. The optimal conditions were that UHP level was 250 MPa, UHP time was 10 min and HCl concentration was 0.75%, under which condition the extraction yield and gel strength of gelatin were up to 88.62% and 384.43 g, respectively. The SDS-PAGE patterns show that the UHP-treated gelatin contains higher mass fraction of high molecular components, such as two different α chains, β and γ-components, compared with that in gelatin treated by traditional method, which is possibly the reason for the high gel strength in UHP-treated gelatin. The results of the study can provide a technical reference for UHP technology application and establishment of clean production process in gelatin preparation.