| Citrus Changshan-Huyou Y.B.Chang was also known as grape-fruit, and it had high nutritional value and medicinal value, Particles had succulent, crisp, sour, sweet with little bitter and delicious tast; peels had full of medical functional components and also was edible materials, therefore, it was selected as research subject in this paper. This paper mainly studied on drinks of grapefruit containing fruit particles and candy products containing fruit peel. The main experimental conclusions were as follows:1) The best stabilizer formula was obtained by complex tests:Complex gums0.20% (CMC 0.04%, XA 0.06%, AG 0.04%, SA 0.06%), sucrose 8.0%, pH4.5.2) At the same time, rheological properties of the best combination were explored. This provided theoretical basis for processing and suspension stability of a longer period of the product.The results indicated that 0.2% Complex gums was non-newtonian fluids, and the the rheological curves could fit well with power law model and the equation of flow curve was Y= 0.1505·X0.6620 (X-shear rate,Y-shear force values;R2=0.9976); thixotropy test showed that 0.2% complex gums was non-thixotropic under the conditions at 30℃, that is, the time that the system required for returning to the state was short after removing external force; Studies on the dynamic viscoelasticity show that under certain conditions, withing the low frequency region gradually transformed into high-frequency region, the system of 0.2% complex gums changes from the weak elastic properties to elastic properties.Rheological properties of complex gums changed with the temperature, pH and sucrose solution.To a certain extent, The temperature could result in the irreversible change of the colloidal molecules structure, and there is no significant conformational transition temperature Tm during the heating-cooling process;the the viscosity of 0.2% complex gums solution affected less within the range of pH4.0-4.5; the viscosity of 0.2% complex gums solution containing 8.0% sucrose would increase, also the solution has the typical viscoelastic characteristics, besides the alternating trend of viscoelastic was more stable.At the same time, compared to the single gums, the 0.2%complex gums solution have an excellent performance in the viscosity and thixotropy under certain conditions. In addition, infrared scan results showed that mixed up the four gel blend, the hydrogen bonds between molecules has increased, so that stretching vibration of-OH increased, and the absorption peak displacement moved to lower wave numbers.3) UV-visible spectrophotometer scans showed that pigment of grapefruit pulp has a characteristic absorption peak at 279nm. And the pigment had better stability at the appropriate temperature range ((?)60℃), indoor or natural light conditions or acidic conditions.4) By single factor experiments and orthogonal test, the best debittering processing of grapefruit peel was obtained:the extraction power 90W, extraction time 10min, solid to liquid ratio 1:40, temperature50℃. And the extraction rate of naringin was measured 5.06% by such processing.5) By orthogonal experiments, optimum recipe of sugar was got:the ratio of maltose syrup to sucrose 1:1 (maltose syrup 30g, sucrose 30g), the substitute proportion of acidic starch to corn starch 50%(acid starch 10g, corn starch 10g), addition level of grapefruit peel powder 5g. And the sensory score was 8.9 by such formula.The results of TA-XT2 test indicated that texture characteristics were different by adding different contents of peel powder, and results of texture properties and sensory evaluation had a certain relationship.correlative analysis between sensory evaluation and texture detection showed that, the index of sensory (morphology, chewiness, viscosity, Comprehensive Assessment) had a closely correlation with the texture properties (Adhesiveness, Springiness, Cohesiveness, Gumminess, Chewiness, Resilienceadhesion), but pigment and flavor didn't have.The results laid the foundation for further processing application of grapefruit. |
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