Oladejo Ayobami Olayemi, Ma Haile
School of Food and Biological Engineering Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China.
Department of Agricultural and Food Engineering, University of Uyo, P.M.B, 1017, Uyo, Nigeria.
J Sci Food Agric. 2016 Aug;96(11):3688-93. doi: 10.1002/jsfa.7552. Epub 2016 Jan 22.
Sweet potato is a highly nutritious tuber crop that is rich in β-carotene. Osmotic dehydration is a pretreatment method for drying of fruit and vegetables. Recently, ultrasound technology has been applied in food processing because of its numerous advantages which include time saving, little damage to the quality of the food. Thus, there is need to investigate and optimise the process parameters [frequency (20-50 kHz), time (10-30 min) and sucrose concentration (20-60% w/v)] for ultrasound-assisted osmotic dehydration of sweet potato using response surface methodology.
The optimised values obtained were frequency of 33.93 kHz, time of 30 min and sucrose concentration of 35.69% (w/v) to give predicted values of 21.62, 4.40 and 17.23% for water loss, solid gain and weight reduction, respectively. The water loss and weight reduction increased when the ultrasound frequency increased from 20 to 35 kHz and then decreased as the frequency increased from 35 to 50 kHz.
The results from this work show that low ultrasound frequency favours the osmotic dehydration of sweet potato and also reduces the use of raw material (sucrose) needed for the osmotic dehydration of sweet potato. © 2015 Society of Chemical Industry.
甘薯是一种营养丰富的块茎作物,富含β-胡萝卜素。渗透脱水是果蔬干燥的一种预处理方法。近年来,超声技术因其具有节省时间、对食品质量损害小等诸多优点而被应用于食品加工。因此,有必要采用响应面法研究并优化甘薯超声辅助渗透脱水的工艺参数[频率(20 - 50千赫)、时间(10 - 30分钟)和蔗糖浓度(20 - 60% w/v)]。
得到的优化值为频率33.93千赫、时间30分钟和蔗糖浓度35.69%(w/v),预测的失水量、固形物增加量和减重率分别为21.62%、4.40%和17.23%。当超声频率从20千赫增加到35千赫时,失水量和减重率增加,而当频率从35千赫增加到50千赫时则下降。
这项工作的结果表明,低超声频率有利于甘薯的渗透脱水,并且还减少了甘薯渗透脱水所需原料(蔗糖)的用量。© 2015化学工业协会。