Research On Chlorophyll Derivatives Preparation In Broccoli Leaves

Broccoli is good natural pigment resources and about0.3%chlorophyll content in it, butaccounts for60%to70%of heavy plant leaves were throw away as garbage. In this paper, take thewaste leaves as materials, we adopted digestion, saponification, replacement, purification,emulsification, embedding technology to research the chlorophyll modification technology forbreaking through the bottlenecks of technology in colour fading, discolour, poor solubility, whichcould improve product performance and ensure the best technical parameters, so we could develop theoily and water soluble chlorophyll copper/zinc acid, water soluble chlorophyll copper/zinc sodiumsalt of6derivatives. By analyzing the stability and inspection, it would develop a new material inpreparing for natural green pigment and provide the theory basis and method for high qualitychlorophyll derivatives. This study is necessary for developing the pigment technical requirements,food safety and human health, it could enhance competitive power of products, which has greatsignificance and underlying economic, social and environmental benefits. The results were as follows:1. Pretreatment method research on broccoli leavesThe test results showed that: the chlorophyll loss in sundried broccoli leaves was the biggest,stoving in60℃and drying in the shade were suitable.2. Extraction technology research on broccoli leaves chlorophyllMethods taking solvent, solid-liquid ratio, extraction temperature, extraction duration andfrequency as factors, L₉（3⁴） orthogonal test was used for Duncan’s significant test. The results showedthat: the optimum combination of chlorophyll extraction technology on broccoli leave was A₂B₂C₃D₁,that was solid-liquid ratio1:5, extraction temperature60℃, extraction time2h,2times, in whichchlorophyll have the highest rate.3. Preparation technology research on chlorophyll copper/zinc derivative of broccoli leavesTest results showed that the optimal conditions of saponification reaction was temperature60℃,pH11,60min; optimal acidification process was pH2-3,20min; optimal replacement response wascopper sulfate/zinc accounts for10%weight of acidified saponification solution, temperature is60℃,displacement time is1.5h, that was A₂B₂C₃, which was the optimum combination of preparation for oilydissolve chlorophyll copper/zinc acid; water dissolve chlorophyll copper/zinc acid products wasprepared with polysorbate80as emulsifier, which was10%weight of chlorophyll copper/zinc acid;optimum preparation for chlorophyll copper/zinc sodium salt was that NaOH alkali and pH11.4. Stability research on broccoli leaves chlorophyll copper/zinc derivativesThe test results showed that: chlorophyll retention of the6products was almost no change indarkness within25h; chlorophyll retention of oily, water dissolve chlorophyll copper/zinc acid was littleeffect while chlorophyll retention of chlorophyll copper/zinc sodium salt was90%in the room withnatural light; chlorophyll retention of oily, water dissolve chlorophyll copper/zinc acid and chlorophyllcopper/zinc sodium salt was82%and40%respectively within25h in sunshine. Products’ tolerance temperature was60℃and it would affected above70℃, chlorophyll retention of oily, water dissolvechlorophyll copper/zinc acid and chlorophyll copper/zinc sodium salt was80%and60%respectively in100℃for25min. PH had no effect on chlorophyll retention of oily, water dissolve chlorophyllcopper/zinc acid, but the suitable pH for chlorophyll copper/zinc sodium salt was9-11, so it could usedin alkaline conditions. The products had anti-oxidation and reduction properties and would not affectedby the VC or sucrose. Cu²⁺had no influence to the stability of the products; Fe³⁺,Al³⁺, and Zn²⁺had noeffect to the stability of oily, water dissolve chlorophyll copper/zinc acid; chlorophyll retention ofchlorophyll copper/zinc sodium salt would drop by the Fe³⁺，Al³⁺and Zn²⁺.5. Inspection analysis on chlorophyll copper/zinc derivatives of broccoli leavesThe test results showed that: the chlorophyll copper/sodium salt products were qualified productsaccording to GB3262-82《food additive chlorophyll copper/sodium salt national standard of thePeople’s Republic of China》, according to national standard testing about chlorophyll copper/sodiumsalt, other chlorophyll products are also qualified products.