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In view of the multi-attribute decision making problems which the attribute values are in the forms of interval numbers, the paper presents an entropy method to obtain the attribute weights using the relative superiority concept. Firstly, the concept of this kind of problem is explained; Then in the light of the basic principle of the traditional entropy value method and train of thought, it given the calculation steps of weights using the relative superiority about the attribute value is interval number multiple attribute decision making problems. Its core is that relative superiority judgment matrix is obtained by comparing with two sets of interval numbers under the same indicator, which the group of interval numbers is equivalently mapped to the exact value form with the merits of relationship, then the weights of each indicator are calculated. Finally, the method is illustrated by giving an example.

BACKGROUND: Many brightly colored fruits and vegetables owe their pigmentation and beneficial health effects to anthocyanins. Unfortunately, anthocyanins in the presence of ascorbic acid are readily degraded over juice processing and storage, which adversely affects color stability and potential health benefits. OBJECTIVE: This project focused on the effect of ascorbic acid as a catalyst in anthocyanin degradation. METHODS: The project involved searching for novel pigmented compounds in a simple model system composed of the most common anthocyanin cyanidin-3-O-glucoside and ascorbic acid, and a second model system consisting of blackberry extract supplemented with ascorbic acid. Degradation products were identified by HPLC-PDA and HPLC-MS. ESR was used to monitor hydroxyl radical formation in the model systems. RESULTS: Over 72 hours at ambient temperature, 67% of cyanidin-3-O-glucoside was lost in the model system during which time an unknown pigmented compound was formed. The unknown compound was also formed in a more complex model system consisting of blackberry extract and ascorbic acid. HPLC with PDA monitoring at 510 nm was used to detect a novel compound and HPLC-ESI-MS3 allowed a proposed structure to be built based on the fragmentation patterns. The unknown structure formed via oxidation of cyanidin 3-O-glucoside by ascorbic acid was identified as 6-hydroxy-cyanidin3-O-glucoside. The mechanism was substantiated with malvidin-3-O-glucoside and ascorbic acid, which produced a hydroxylated malvidin-3-Oglucoside. Production of hydroxyl radical in the base and blackberry model systems was confirmed by ESR. CONCLUSIONS:We propose that the pigmented compound is formed from hydroxyl radicals via the Haber-Weiss reaction. The addition of food grade hydroxyl radical scavengers to juices may be a viable treatment to prevent ascorbic acid-catalyzed degradation of anthocyanins.