17114
The results indicated that the two pretreatments could more effectively maintain quality and could extend the shelf life by 6 - 8 days compared with the control group during refrigerated storage .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None