Processing Technology Of Orange Juice And High Value-added Development Of Orange Peel

People love orange juice with good color,flavor and nutrition.After the oranges are juiced,the orange peel is often thrown away as garbage,which causes serious waste of orange resources and certain environmental pollution.It is very important to deeply develop orange peels,which are rich in carotenoids,pectin and other high value-added components.For this reason,this study takes orange as the processing object and develops a new technology for the making of orange juice strengthened by orange peel.At the same time,the extraction technology of orange peel pectin by ultrasound-assisted acid method is discussed,and the extraction technology of orange peel pigment is optimized.The main findings are as follows:(1)Taking orange fruit gravy,orange peel pulp,sugar and citric acid as indicators,single factor experiment is conducted to explore the influence of each factor on the strengthening of orange juice.The orange peel is pressed into a liquid and add to the orange pulp fresh juice,that is,non-self-concentrating orange juice.Orange peel pericarp by crushing,washing,pressing,filtering and other natural orange peel pulp,can make orange fruit gravy color and nutrition e nhance,such as carotene,vitamin C,aroma ingredients,etc.The orange juice prepared by this method not only has the advantages of traditional fresh pressed orange juice,but also increases the original components of natural orange peel and orange peel.The enhancement of this orange juice does not use synthetic reagents,that uses the natural orange exocarp,thus improving the sensory properties of orange juice products.The most influential factor is the addition of orange juice and sugar,and the least influential factor is the addition of citric acid.The best formula is determined to be 43% orange juice,4.0% orange peel pulp,5% white sugar and 0.05% citric acid.Three parallel experiments are carried out,and the average sensory score of the beverage was 92.1.In order to avoid the stratification of orange juice beverage during storage,three stabilizer xanthan gum,sodium carboxymethyl cellulose and pectin were selected for single factor and orthogonal test,The results showed that sodium carboxymethyl cellulose 0.09%,pectin 0.06% and xanthan gum 0.05% were the best additives.(2)The effects of ratio of material to liquid,extraction temperature,extraction time and p H on extraction effect of orange peel pectin are studied.Ultrasonic assisted acid method is used to extract pectin.In extracting orange peel pectin,hydrochloric acid is the most suitable solvent.The ratio of material to liquid is 1:50,the extraction p H is 2.0,the extraction temperature is 70?,and the extraction time is 70 min.The extraction rate of orange peel pectin is the highest.The decolorization of activated carbon,ab-8 resin,d-101 resin and diatomite was studied to purify the crude pectin extracted by ultrasonic assisted acid method,and the purification effects of several adsorbents on pectin were compared,and the p Hysicochemical indexes of pectin before and after purification were determined.(3)The pigment extraction of orange peel is optimized,and the effects of the factors such as the ratio of material to liquid,extraction time,ethanol concentration and extraction temperature on the extraction efficiency are investigated.On the basis of single factor,orthogonal test is carried out to determine the optimal extraction conditions of pigment as material-liquid ratio 1:75,extraction temperature as 50?,ethanol solution volume fraction as 95%,extraction time as 70 min,and the main influencing factors as material-liquid ratio.The average absorbance value of orange peel pigment is 1.021,and the extraction yield is higher.