传统的麦芽饴糖在加热或灭菌时出现絮凝沉淀物的现象，是饴糖产品较为普遍存在的质量问题，影响了其食品饮品的加工应用。本文在4.50~5.50的pH值范围内，通过100 ℃水浴和灭菌加热的处理，发现对问题饴糖产品的热絮凝物的产生量的影响很小，糖液的湿絮凝物得率都约1.50%。研究发现絮凝沉淀物呈现多量的无定型区外，也具有一定的结晶结构，红外光谱与蛋白含量83.77%的大米蛋白样品很接近；主要为蛋白质和灰分，含量分别为81.79%和17.66%，脂肪含量低；絮凝沉淀物所含的碳、氢和氧之外的元素，硫元素含量比例最大，铁、钙、硅和氯元素次之，构成了絮凝沉淀物灰分的主体；其550 ℃灼烧后残留的灰分试样，主要为二氧化硅的组分，为硅藻土助滤剂所带来的杂质物质。饴糖中的蛋白质在热絮凝物形成过程中起主导作用，其它的钙、铁、硅等元素或离子的成分物质也促进了蛋白质的热絮凝。

The flocculent precipitate formed when traditional maltose syrup is exposed to heat or sterilization treatment is a relatively common quality problem, limiting the application of maltose syrup in food and beverage processing. In this study, a water bath at 100°C or sterilization treatment at pH 4.50 to 5.50 showed a minimal effect on the amount of floc produced by heat in maltose syrup and the generation rate of wet sedimentation of maltose syrup solution was approximately 1.50%. The results also showed that the flocs contained crystalline structure in addition to a large number of amorphous regions. The infrared spectrum of the floc was very similar to that of rice protein, with a protein content of 83.77%. The floc was mainly composed of 81.79% protein and 17.66% ash, with a small amount of fat. In addition to carbon, hydrogen, and oxygen elements, sulfur was present in the highest proportion in the floc, followed by iron, calcium, silicon, and chlorine; sulfur was the main component of the ash in the floc as well. The main component of the residual ash samples after calcination at 550°C was silica, derived from the impurities in diatomite filter aid. Proteins in the maltose syrup play a major role in the heat-induced flocculation process and other elements such as calcium, iron, silicon, and ions also promote the heat-induced flocculation of proteins.

国家自然科学基金重点项目（31130042）；广州市科技计划项目（2012J430058），