| Fresh-cut Chinese water chestnut (Eleocharistuberose Schult) (CWC) is mechanical injuried after minimumlly processed. There will be more physiological and biochemical reactions unbenefited for fruit storage, which can make fruit quality deterioration and shorten fruit shelf-life. Mild heat pre-treatment (MHPT) is non-toxic, efficient, economic, safe and harmless to the human and environment, which may be concerned by more and more people recently.In this paper, the fresh-cut CWC were treated by heat water combined with modified atmosphere package, and a central composite rotation designed combine response surface methodology also used in the experiment design. The effects of heat treatment time, temperature and storage time on storage quality and nutrition content of fresh-cut CWC were studied in the paper. The treatment which can best inhibit fruit browning (58℃, 20 min) were used to anlysis the browning index (BI), total phenol (TP) and flavonoid content, phenylalamine ammonialyase (PAL) activity, which may explain anti-browning mechanism in fresh-cut CWC by heat treatment. Meanwhile, we evaluated the fruit sensory quality with quantitative descriptive analysis and principal component analysis on the best anti-browning treatment. The results were as follows:1. Effect on fresh-cut CWC quality by MHPT(1)The model of DYI was Y=737．1416-24．844*X1-14．08333*X2+138．5307*X3+0．202121*X1*X1+0．454086*X1*X2- 1．607526*X1*X3-0．231567*X2*X2-0．453299*X2*X3-2．022502*X3*X3 Effects on fresh-cut CWC DYI by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature) and X1 * X3 (the cross-term of temperature and storage time). When the fresh-cut CWC treated under 54℃in 20 min, and storage for 3 days, the minimum predictive value of DYI was 211.16.(2)The model of DA was Y=-4．88157+0．265497*X1+0．133329*X2-1．880605*X3-0．002684*X1*X1-0．005903*X1*X2+ 0．029531*X1*X3+0．005049*X2*X2+0．002778*X2*X3-0．038961*X3*X3Effects on fresh-cut CWC DA by MHPT were in a significant impact (0.05 level) in factors X3 (storage time). When the fresh-cut CWC treated under 52℃in 22 min, and storage for 3 days, the optimital predictive value of DA was -1.03.(3)The model of DB was Y=-563．766+11．8074*X1+9．01506*X2+52．20502*X3-0．104083*X1*X1+0．031273*X1*X2- 0．196042*X1*X3-0．253674*X2*X2-0．103056*X2*X3-1．549728*X3*X3Effects on fresh-cut CWC DB by MHPT were in a significant impact (0.05 level) in factors X3 (storage time). When the fresh-cut CWC treated under 55℃in 20 min, and storage for 3 days, the optimital predictive value of DB was -0.16.(4)The model of BI wasY=-13．12586-0．501611*X1+0．017973*X2+0．62717*X3+0．004278*X1*X1+0．002562*X1*X2- 0．013511*X1*X3-0．003581*X2*X2-0．004117*X2*X3+0．034815*X3*X3Effects on fresh-cut CWC BI by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature), X3*X3 (the square of storage time) and X1 * X3 (the cross-term of temperature and storage time). When the fresh-cut CWC treated under 58℃in 20 min, and storage for 5 days, the minimum predictive value of BI was 0.03.(5)The model of firmness wasY=-4382．3+187．7405*X1+38．52248*X2+90．67424*X3-1．341601*X1*X1+0．122685*X1*X2- 1．385417*X1*X3-1．265478*X2*X2+0．25*X2*X3-4．307243*X3*X3Effects on fresh-cut CWC firmness by MHPT were in a significant impact (0.05 level) infactors X1 (heat treatment temperature), X3 (storage time), X1*X1 (the square of heat treatmenttemperature) and X2*X2 (the square of heat treatment time). When the fresh-cut CWC treated under 64℃in 20 min, and storage for 4 days, the maximum predictive value of firmness was 2509.09N.(6)The model of fracturability wasY=-5026．33+184．2211*X1-17．27665*X2+218．6314X3-1．63926*X1*X1+0．358796*X1*X2- 1．234375*X1*X3+0．309212*X2*X2-0．861111*X2*X3-7．615962*X3*X3Effects on fresh-cut CWC fracturability by MHPT were in a significant impact (0.05 level) in factors X1*X1 (the square of heat treatment temperature) and X2*X2 (the square of heat treatment time). When the fresh-cut CWC treated under 56℃in 29 min, and storage for 8 days, the maximum predictive value of fracturability was 996.10N.2. Effect on nutrition content of fresh-cut CWC by MHPT(1)The model of ascorbic acid (AsA) wasY=2．147926+0．042608*X1-0．00388*X2+0．049781*X3+0．000053*X1*X1-0．002088*X1*X2- 0．010756*X1X3+0．0027*X2*X2-0．000397*X2*X3+0．038434*X3*X3Effects on fresh-cut CWC AsA by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature) and X3*X3 (the square of storage time). When the fresh-cut CWC treated under 47℃in 20 min, and storage for 10 days, the maximum predictive value of AsA is 2.51mg/100g.(2)The model of total solid soluble content (TSS) wasY=95．46889-0．133824*X1-0．135795*X2-7．736579*X3+0．008338*X1*X1-0．036991*X1*X2- 0．082396*X1X3+0．043303*X2*X2+0．046806*X2*X3+0．751542*X3*X3Effects on fresh-cut CWC TSS by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature) , X3 (storage time) , X2*X2 (the square of heat treatment time) ,X3*X3 (the square of storage time) and X1*X3 (the cross-term of temperature and storage time).(3)The model of pH wasY=-4．39873+0．34586*X1+0．04376*X2+0．13277*X3-0．002949*X1*X1+0．001551*X1*X2- 0．004323*X1*X3-0．002646*X2*X2-0．002153*X2*X3+0．007488*X3*X3Effects on fresh-cut CWC pH by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature) , X1*X1 (the square of heat treatment temperature) and X2*X2 (the square of heat treatment time). When the fresh-cut CWC treated under 59℃in 22 min, and storage for 3 days, the maximum predictive value of pH was 6.95.(4)The model of the ration of water loss (RWL) wasY=-5．4678+0．14147*X1+0．230417*X2+0．05776*X3-0．001247*X1X1-0．00136*X1*X2 +0．003244*X1*X3-0．003568*X2*X2-0．001611*X2X3-0．000192*X3*X3Effects on fresh-cut CWC RWL by MHPT were in a significant impact (0.05 level) in factors X1 (heat treatment temperature), X3*X3 (the square of storage time) and X1 * X3 (the cross-term of temperature and storage time). When the fresh-cut CWC treated under 58℃in 19 min, and storage for 3 days, the minimum predictive value of RWL was 0.81%.3. The experiment of anti-browning indicated that CWC fruit BI and PAL activity in control and heattreatment were increased during the storage. The BI, PAL activity, TP and flavonoid content of control fresh-cut CWC fruit were always higher than that of heat treatment.4. The main sense of fresh-cut CWC:(1) Color description language was white, yellow-green and brown; Texture description language was wetting, rough, fibrous and brittle; Flavor description language was fresh, com flavor, faint scent, alcohol flavor and taste moldy.(2) Quantitative descriptive analysis (QDA) showed that the heat treatment could effectively delay the discoloration of CWC slices, flavor and texture.(3) Principal component analysis (PCA) showed that there were three main components. The weight of the first principal component was 24.81%, and major features were milky white, yellow-green, brown and rough. The weight of the secend principal components was 22.33%, and major features were fresh, faint scent and mildew. The weight of the third principal components was 13.74%, and major feature was fibrous.
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