Research And Application Of Plant Extracts On The Chili Postharvest Fresh-keeping

Chili, as one of the most important fruit crops in the world, because of its high nutritional value, high output, high demand, planting area expands unceasingly in recent years. However, Chili has many characteristics, such as sensitive to low temperature, perishable, this a series of problems constrained the development of the pepper industry. Chili used more chemical preservatives of preservation of postharvest fruits for a long time, but Chemical preservatives of long-term use can cause environmental pollution and destruction of ecological balance, and chemical residues also brought harm to human health. Therefore, developed a new, safe, non-toxic botanical antistaling agent become imperative.The pepper (Xiangyan NO.5) treated withplant extracts. The feasibility of different plant extracts coating on fresh-keeping of pepper (Xiangyan NO.5) the optimized and selecting of plant extract was discussed through analysis of weight-loss rate, rotting rate, respiration intensity, VC content, chlorophyll content and soluble solid content. At the same time, through the single factor experiment and orthogonal experiment, the optimized pepper storage conditions is determined. On the basis, weight-loss rate, rotting rate, respiration intensity, nutrient qualities and enzyme activity measured were respectively in order to explore its fresh-keeping, which provide theoretical basis for short-term preservation of pepper (Xiangyan NO.5). Main results for this study are as follows:1. The screening of plant extracts:pepper was soaked by 16 50g·L-1 plant extracts at first,then we determined weight-loss rate and rot rate on the 16th after storage in 20??75%(RH) against pepper. The results showed that Rheum palmatum L, Ilex chinensis Sims and Ligustrum lucidum Ait,Rheum palmatum L and Cinnamomum camphora (L.) Presl showed high fresh-keeping activity to pepper.Compared with CK treatment,weight of loss was respectively decreased by 48.02%,48.97%,48.48%, 56.94%,50.97%, rot loss was respectively decreased by 30%,39.99%,39.99%, 79.98%,79.98%?2. The plant extract of the Secondary screening by system verification:With a concentration of 50g·L-1 16 kinds of plant extract to soak the peppers (XiangYan NO.5 of Hunan province), The temperature is 20?, humidity is 75% under the condition of storage, every 7 days sampling detection of pepper's respiration intensity, brightness, color, saturation, chlorophyll content, soluble solid content and Vc content for the determination of indicators, the results showed that after 21 d storage. The results showed that after 21 days The Ilex chinensis Sims extract respiration intensity reducted 8.63% significantly which compared with sterile water group'(CK), and the brightness, color, saturation decline rate reduced to 8.41%,1.5% and 6.77% respectively; The content of VC and chlorophyll rate was reduced by 30.52% and 34.24% respectively; Soluble solids content increased by 11.29%;The best effect on brightness and saturation was fructus ligustri lucidi group,but there was no significant sexual difference which compared with wild Holly group', So pick wild Holly extract as the best preservative for capsicums (Xiangyan NO.5).3.The Ilex chinensis Sims extract on process optimization study of preservation of the peppers:With fresh of pepper (XiangYan NO.5 of Hunan province) were used as material, weight-loss rate and rotting rate as the evaluation index, By single factor and orthogonal experiment to optimize the best preservation conditions were determined, the results showed that at the end of the storage, In the soaking time of 2.5 min, temperature 10?, Ilex chinensis Sims extract concentration of 125 g·L-1, the concentration of the emulsifier twain 20 under the condition of 0.02%, the best effect of preservation of pepper. The comprehensive score of 95.67, weight-loss rate is 2.33% and rotting rate is 5.67%.4. The Ilex chinensis Sims effects of postharvest fresh-keeping of the peppers: With fresh of pepper (XiangYan NO.5 of Hunan province) were used as material,for the preservation conditions.With the sterile water group (CKl) as negative control, the preservation solution group(CK2) as Positive control and the Ilex chinensis Sims group(ZJZ) (Soak time of 2.5 min, temperature is 10?, Ilex chinensis Sims extract concentration of 125 g/L, the concentration of the emulsifier twain 20 is 0.02%). temperature is 10?, humidity is 75% of storage in the environment, the study of its impact on chili preservation effect.The rotting rate was reduced respectively by 23.34% and 16.67%, During the whole storage, the Ilex chinensis Sims group(ZJZ) delayed the pepper weight-loss rate and rotting rate; Significantly reduced the pepper chlorophyll, vitamin C, soluble solid content, significantly inhibited the malondialdehyde (MDA) accumulation; Significantly improved the defense enzyme polyphenol oxidase (PPO) and peroxidase (POD) and catalase (CAT) activity. So the Ilex chinensis Sims group (ZJZ) can better keep the pepper value and commercial value, significantly improve the storage effect of pepper. Provide theoretical reference for chili postharvest fresh-keeping.