3.4. Color
Color is an important parameter for determining the quality of fresh products and the quantity of anthocyanins which known as a responsible compound of attractive, red color of strawberry ( Rodrigo, Van Loey, & Hendrickx, 2007). Changes in L* values for different treatments during storage are shown in Table 3a. The statistical analyses showed that interactions of factors (including two and three factors) were not significantly important. On the other hand, main effects of storage time and ultrasound power were statistically significant (Tables 3b and 3c). Statistically significance was found between 90 W and 30e60 W treatments. The results of L* values indicated that 30 W and 60 W treatments were effective to preserve the bright color of strawberry when compared with CNT and 90 W.