Quality Changes And Control Technology Of Fresh-Cut Pear During Storage

Pear, one of high yield fruits, is famous for its nutrition and health value, as well as its abundance. Doing minimally process on pear is a significant method which could extend shelflife, improving added value and increasing the integrated output value. The pear wouldbecome browning, soft, sensitive to microorganism, and nutrition loss, because of the harmcaused by machine, leading to quality loss and reducing of storage life, affect the qualities andcommercialization of pear products. In this paper, with large pear in china as raw materials,studied the appearance, hardness, and nutrition qualities in different various, the use ofascorbic acid, Calcium ascorbate and citric acid treatment on the qualities of pear duringstorage. The main conclusions and results were as followings:1. The changes of qualities of different fresh-cut pears: these varieties of fresh-cut pearshas similar variation trend of color, crispness, hardness and the content of reducing sugar, butthe content of vitamin C is different from each other and decreases all the time, the content ofvitamin C in Huangguan pear is higher, followed by Suisho. Different species may havevarious content of soluble phenolic. The activities of PPO were quite different and had bigchanges during the storage period.Suisho is suitable for fresh-cut processing, because of slight browning, better hardnessand crispness, less nutrition loss, and woret cellular membrane permeability. For six days, itcould keep good qualities. Followed by WhangKeumBae, whose PPO activity is low, browndegree is low, and hardness is appropriate. Sydney, Changba pear, Laiyang pear is notsuitable for processing, because of severe brown degree and soft tissue.2. The treatment of ascorbic acid has a good impact on qualities of pear, which couldalleviate brown degree, decrease the activity of PPO, low the consuming of phenolic andreducing sugar, also, increase the content of vitamin C, which is a source of vitaminsupplement, and there is no significant effect on crispness and hardness.3. The treatment of Calcium ascorbate could alleviate brown degree, decrease cellularmembrane permeability, the activity of PPO and the consuming of vitamin C, and it isbeneficial to maintain level of crispness and hardness, which could keep good superficialqualities, and trophic value. 4. The treatment of citric acid could alleviate brown degree, decrease the consuming ofsoluble phenolic, low the activity of PPO, and harden pear tissue at some level, but thistreatment could not decrease the consuming of vitamin C and reducing sugar significantly.5. The results of composite inhibitors orthogonal test were as below: different browninginhibitors have various effects when applied, ascorbic acid have marked is impact on colorand luster degrees, followed by citric acid and Calcium ascorbate. Calcium ascorbate is moresuitable than ascorbic acid and citric acid when applied to keep crispness. With regarding tohardness, Calcium ascorbate is preferable than citric acid and ascorbic acid. Taking all threeparameters into consideration, best proportioning is obtained, Calcium ascorbate is4.0g/100g,ascorbic acid is2.4g/100g, and citric acid is1.0g/100g.