PULSED VACUUM OSMOTIC DEHYDRATION ON PHYSIOLOGICAL COMPOUND ENRICHMENT OF MODEL FOOD

Abstract

The objective of this study is to apply a response surface methodology in optimizing pulsed vacuum osmotic dehydration to achieve suffcient solids in a gel matrix using a diluted solution. Application of PVOD enrichment of antioxidant compounds and nutrients is also investigated. The process variables are agar-gel bulk density (0.65-0.85 g/ ml), sucrose concentration (30-60% w/w) and vacuum impregnation time (10-30 min). The results show that process variables, especially sucrose concentration, signifcantly affected moisture content (MC), water loss (WL) and solids gain (SG) of a model food. A quadratic model was ftted for WL, SG, weight reduction and total soluble solids prediction (R2 0.997 - 0.999). The prediction of total soluble solids was the most precise (X2 0.095). Optimum conditions were 32.58%w/w for sucrose content, 0.8 g/ml in bulk density and 14.34 min vacuum time. The physiological compounds can be suffciently introduced into the model food with a diluted solution. The results may be applied to the development of new innovative products that provide the desired compound level and functionality. This will increase product value, utilization of agricultural produce, and reduce the loss of freshness in seasonal produce, especially tropical fruits.