Pei-Yu Tien1, Pei-Fen Yang1, Yih-Ming Weng1, Zer-Ran Yu2 and Be-Jen Wang1*
1Department of Food Science, National Chiayi University, Chiayi, Taiwan, R.O.C.
2Superwell Biotechnology Corporation, Taichung City, Taiwan, R.O.C.
Corresponding Author E-mail:bejen@mail.ncyu.edu.tw
Broccoli provides a good source of many nutrients and bioactive compounds. However, bitterness of broccoli deterred sensory desirability and furthermore impacted its consumption. Cooking and seasoning addition can be used to reduce the bitterness and to increase the preference of vegetables. The objective of this study aims to investigate the effect of blanching and flavor enhancement with various sauces on the bioactive and organoleptic properties. Broccoli was prepared: raw (C), blanched (B), blanched and flavored with Japanese style sauce (F1), with cheese (F2), and with Chinese style sauce (F3). The bioactive compounds (polysaccharide and phenolic compounds), antioxidant properties (DPPH and ABTS scavenging activities), and sensory preference characteristic were evaluated. The results showed blanching and combined with seasonings significantly altered the color parameters (a*, C* and ho) of broccoli. While blanching and sauces additions improved antioxidant contents and capacity as well as all sensory acceptances tested. Compared to the control, blanching and sauces additions increased the contents of phenolic compounds and polysaccharides from 8.3 to 8.4-10.0 and from 78 to 93-106 mg/g dw, respectively. While blanching and sauces increased the scavenging capacity of DPPH and ABTS from 1.29 to 1.43-1.83 and from 3.28 to 4.52-5.27mg Trolox/100g, respectively. Principal component analysis (PCA) analysis further showed blanching and sauces additions were positively correlated with the acceptance of flavor, taste and overall but negatively correlated to color acceptance. In conclusion, blanching or flavorings retained color acceptance (sensory score >5) and enhanced antioxidant capacity and sensory preference.
Antioxidant capacity; Blanching; Broccoli; Flavor enhancement; Sensory preference