size, crispiness and Panang flavor were in range of ‘neither like nor dislike’ to ‘slightly like’ (5.0-6.5), while spiciness ranged from ‘slightly dislike’ ‘to moderately dislike’ (3.5). This information can be combined with the results of the ‘Just about right’ scale to determine the direction of improvement. The
Table 3. Chemical composition, anthocyanin content and energy of black glutinous rice cracker
Figure 4. Color of black glutinous rice cracker during storage; a) lightness, b) redness and c) yellowness
criteria of ‘just about right’ was set at 70%, therefore, crispiness of rice cracker was just about right (72%). However; the optimum score of the other sensory attributes was less than 70%, hence net-effect should be considerable in the next order where net-effect represents direction of improvement. A negative value of net-effect should lead to a reduction in the intensity of the specific attribute, while a positive value should lead to increasing the intensity of that attribute (Prinyawiwatkut, 2010). Generally, the criterion of net-effect is set at less than -20 or higher than 20. Thus, size should be larger and color should be less intense. However; most panelists agreed that the rice cracker was too spicy. Consequently, the amount of chili was varied and the result is shown in Table 2. No significant difference in color, size, crispiness, Panang flavor and saltiness were found among each other (p > 0.05). On the other hand, spiciness and overall liking were significantly different with a lesser amount of chili corresponding to a higher preference score. Hence, the finished product of black glutinous rice cracker had no chili powder added to it. The confirmation of this formula with 50 panelists was showed that the mean score of overall liking and consumer acceptability were 7.2±1.2 and 84.5%, respectively