Effects of preservatives on postharvest quality of

Effect of preservative on postharvest quality of Hami melon at room temperature (1)

Abstract: the effect of different concentrations of preservative amistai dip on postharvest quality of Hami melon at room temperature was studied. Through the regular determination of vitamin C content, sugar acid content, hardness and other indicators of Hami melon stored after treatment, it is shown that amistai dip has a certain protective effect on the quality of Hami Melon during storage. The ratio of vitamin C content, sugar acid content, hardness and other indicators of Hami melon after harvest through different concentrations of treatment

shows that: when it is packed with PE (polyethylene) fresh-keeping film, the fresh-keeping effect is the best when the concentration of amistai dip is 100mg/kg. After 30 days of storage, the effect showed that amistai dip could significantly inhibit the degradation of sugar, acid, 7, digital display timer: 1 ~ 99 minutes of vitamin C, delay the aging of Hami melon, and maintain its good quality

key words: Hami melon: preservative: post harvest quality

Hami melon is famous at home and abroad for its excellent quality, unique flavor and rich nutrition. Hami melon production is highly regional and seasonal. The perishability in the process of post harvest storage and transportation and the corresponding fresh-keeping measures are not perfect, which restricts the level and scale of Hami melon production and management. At present, the way of long-distance transportation of Hami melon in Xinjiang is mainly highway transportation, and the means of transportation is mainly ordinary freight cars without temperature control facilities. Therefore, what are the operating procedures and test requirements of impact testing machine for fresh-keeping technology research in the process of post harvest storage and transportation, as well as discussion, demonstration The promotion of preservatives suitable for Hami melon preservation is of great importance at this stage [21. The author uses the preservative amistai dip (a biological preservative introduced from Australia) The experiment of keeping Hami melon fresh at room temperature was carried out, and the effect of antistaling agent amistai dip on the quality of Hami Melon during postharvest storage was studied, so as to explore the effect of antistaling agent amistai dip on the postharvest storage and preservation of Hami melon and its adaptive concentration, which has a certain role in the development of Xinjiang Hami melon production and management, storage, transportation and marketing industrialization

1 materials and design

1.1 experimental materials

1.1.1 experimental materials early queen, fruit oval, The peel is yellow and covered with light green spots, with fine lines. The pulp is orange red and crunchy, with an average weight of 3.5kg per melon

1.1.2 storage room: Laboratory of postharvest physiology of fruits and vegetables, School of food science, Xinjiang Agricultural University

1.1.3 antistaling agent amistai dip is a biological antistaling agent provided by Australian ACIAR (Australian Centre for Intelligent Agricultural Research)

1.1.4 the fresh-keeping bag is a low-density polyethylene plastic film fresh-keeping bag with a size of 33cm~25cm and a thickness of 0.03mm

1.2 the experimental design was a completely randomized design. Amistai dip designed three different concentrations (set as a, A2, A3), and each concentration was repeated three times. And there is a control CK water. As follows: a-amistai dip, ai-50mg/kg, a2-100mg/kg, a3-1 50mg/kg, each concentration treated 60 melons, a total of 180 melons; At the same time, 90 melons were taken as blank control

1.3 experimental method

1.3.1 the indoor temperature is 20 ~ 25 ℃. The relative humidity is 85% - 90%. On August 18, 2004, the company of Kazakhstan deliberately built a factory in Rhodes to produce melons locally. Dilute the preservative to the designed concentration, add 2 ~ 3 drops of Tween (polysorbate) to the prepared solution and spray it evenly on the surface of melon. Bag the melon after its skin is naturally dried. When bagging, six small holes are punched in each bag with a counter weight

1.3.2 measure the content of VC, soluble solids, hardness and organic acid every five days

(1) determination of VC content: 2,6. Dichlorophenol indophenol sodium calibration method

(2) determination of soluble solid content: Determination of W 1 handheld sugar meter

(3) determination of organic acid content when the temperature reaches 1250 ℃: titration method

(4) hardness measurement: Taylor durometer

(5) determination of decay rate: turn the melon once in 2 ~ 3 days. Comprehensively check the decay of melons on the 15th day and the 30th day respectively, and eliminate the melons with a heavy degree of decay. Set four decay levels of 0, 1, 2 and 3 according to the natural decay degree of melon to record the decay of melon. Grade 0: the melon is intact without any decay. Grade 1: melon has a slight decay, with an area of no more than 2 cm2. Grade 2: the rotten area of melon surface is about 1/4, and most of them are still edible. Grade 3: the rotten area of melon exceeds 1/3. Calculate the good melon rate with grade o~1 melon, and grade 2 or above is rotten melon

(6) calculation of weight loss rate

weight loss rate = (weight of melon when bagging. Weight of melon when measuring)/weight when bagging × 100%

(to be continued)