Establishment Of Browning Model Of Nanfeng Tangerine Juice And Anti-browning Technology

The Nanfeng tangerine with beautiful appearance, good sweet-acid balance, fragrant characteristic and rich in nutrition has been famous in the world, is china famous citrus variety. Nanfeng tangerine has been mainly used for fresh-eating market, but in recent years, with the expansion of planting scale, and the fresh-eating market go to saturation, it showing signs of processing contradiction. Until 2011, the yield of Nanfeng tangerine will exceed 100 million ton. Every year there are more than 200 thousand ton inferior tangerine wait for processing. We must study the processing of Nanfeng tangerine.Now, domestic study on Nanfeng tangerine processing is less, meanwhile citrus processing what is the main type of tangerine juice processing is also facing a series of key technical problems. The changes of flavor and senses often occur in the processing in of tangerine juice, and non-enzyme browning always takes place in the storage and transport. Now, we must make a breakthrough in Nanfeng tangerine juice processing, especially in the non-enzymatic browning and anti-browning of Nanfeng tangerine juice.This article makes some study in non-enzyme browning in Nanfeng tangerine juice through make a tangerine juice model. The article research the every variable in juice model, and the effect on browning of the component. After these experiments, we can conclude that:1. By HPLC and amino acid analyzer, the Nanfeng tangerine major component as follows:sugars,16.16%; citric acid,0.83%; ascorbic acid,0.04%; amino acid,0.37%. According to this data, we make the browning model.2. In order to detect the products of browning model and browning processing such as 3-Hydroxy-2-pyrone,5-Hydroxymethylfural, and Furfural, we need to establish a new RP-HPLC method. Through the experiment, we discover the best optimized conditions are:The HPLC system use Amethyst C18-H column, the detection wave length is 280 nm, the mobile phase is a mixture of 0.1% acetic acid/acetonitrile(95/5, V/V) with the flow rate 1.0 mL/min, the column temperature is 30℃and the sample volume is 10μL. The accuracy of the method is confirmed with an average recovery range are 104.14%, 102.36%,100.53%. The Relative Standard Deviation (RSD) of this method is 1.58%, 2.18%,5.41%. It’s a convenient and accurate method for analyzing 3-Hydroxy-2-pyrone, 5-Hydroxymethylfural and Furfural.3. On research the effect relation of Nanfeng components on browning, found that 5-HMF mainly comes from the maillard reaction,3OH2P mainly comes from ascorbic acid. Ascorbic acid can restrain the medium-term Browning. Citric acid has a better anti-browning ability within the system. And in the browning model, each amino acids have a different influence to browning. Line up a preface by inertia of each amino acids to browning as follows:PHE>ARG>SER>GLU>ASP>CYS.4. To summarize the study of juice browning model, we try to do a series of anti-browning to juice. Finally, with the 1.0 mg/mL citric acid,0.3 mg/mL ascorbic acid and 0.035 mg/mL L-cysteine, we can get good anti-browning.