油炸温度与时间对白公干鱼传质特性及品质的影响

以白公干鱼为研究对象,探究不同油炸温度(160,180,200℃)和油炸时间(0,20,40,60,80,100,120,150,180s)对白公干鱼水分损失和吸油率的影响,采用特定指数方程对油炸过程中的传质动力学进行曲线拟合;测定油炸后白公干鱼水分活度,建立水分活度与水分含量的关系;测定油炸后白公干鱼色泽、硬度、咀嚼性、表层硬度、韧性,并进行感官品质分析。结果表明:油炸温度的升高可显著增大白公干鱼的水分损失速率和吸油速率,且拟合曲线均符合特定指数方程;白公干鱼水分含量和水分活度呈正相关性,并分为两个区域:水分含量<22%时水分活度随水分含量的增加而快速增大,水分含量>22%时水分活度随水分含量的增加而趋于平缓;结合企业生产经验和感官品质分析,油炸后白公干鱼水分含量控制在22%～26%为宜,达到此水分含量且吸油率最低的加工条件为180℃油炸180s。

Effects of frying temperature and time on mass transfer and quality of White Business fish

Taking the White Business fish as the research object,explored effects of different frying temperature(160,180 and200℃)and frying time(0,20,40,60,80,100,120,150 and180 s)to moisture loss of White Business fish and oil absorption rate.Used specific exponential equation of mass transfer in the process of fried dynamics for curve fitting.At the same time,the water activity of White Business fish after frying was measured,and the relationship between water activity and water content was established.The color,hardness,chewiness,surface hardness and toughness of fried White Business fish were measured.The results showed that the rate of water loss and oil absorption of White Business fish were significantly increased with the increase of frying temperature,with a great positive correlation between water content and water activity of White Business fish,which can be divided into two areas:when water content was lower than22%,water activity increases rapidly with the increase of water content;when water content was higher than 22%, water activity tends to be flat with the increase of water content.Combined with the experience of production and the analysis of sensory quality,it is advisable to control the water content of the White Business fish after frying at 22% ~26%.The condition that the water content of the dried fish can reach this level and the lowest oil absorption rate under the experimental frying temperature is 180 sfried at 180℃.