本论文根据生猪屠宰企业实际生产情况，针对目前企业猪胴体预冷过程中传统喷淋方式存在智能化程度低，人为因素影响较大，预冷损耗偏大的问题。研究预冷库环境、季节、不同预冷方式等因素对预冷损耗、胴体品质以及猪胴体表面菌落总数的影响，为减少猪胴体预冷损耗，提高肉品品质提供理论依据。 1.猪胴体预冷过程中预冷损耗影响因素的研究 本研究在春、夏、秋、冬四个季节（1月，3月，7月，11月）从屠宰企业选取宰后猪胴体，将猪胴体分布于预冷库内的九个位置，研究预冷库内不同位置的风速、温度、湿度的变化规律、不同预冷时间（7h以下，10h～14h，24h～29h，30h～34h，45h以上）以及不同季节（1月，3月，7月，11月）对猪胴体预冷损耗的影响。结果表明：预冷库内不同位置之间的风速、温湿度变化规律的差异对猪胴体预冷损耗影响显著（P<0.05)，预冷库内风速大的位置胴体周围环境湿度高，温度低，胴体冷却损耗小；预冷时间对冷却损耗有显著影响（P<0.05)，当预冷时间超过45h时，其预冷损耗高达2.11%；季节对于预冷损耗影响显著（P<0.05)，夏季由于气温高，胴体中心温度下降较慢，胴体水分蒸发多，其预冷24h的预冷损耗为1.76%，显著高于其他季节（P<0.05)。 2.雾化喷淋技术的的研究 本研究在春、夏、秋、冬四个季节（1月，3月，7月，11月）从生猪屠宰企业选取宰后猪胴体，将宰后猪胴体放置于安装有新型雾化喷淋设备的预冷库，研究不同喷淋时间（8h，9h，10h，11h，12h)对猪胴体预冷损耗、表面菌落总数、水痕面积以及色差的影响，据此选取新型雾化喷淋设备的最佳喷淋时间以及最佳喷淋频率。而后在不同季节、不同预冷时间条件下对比新型雾化喷淋，传统喷淋，未喷淋三种处理方式下猪胴体预冷损耗、胴体表面菌落总数、胴体表面色差以及预冷库环境（温湿度）。结果表明：雾化喷淋时间对于预冷损耗，菌落总数，和水痕面积有显著影响（P<0.05)；新型雾化喷淋设备的最佳时间为10h，最佳喷淋频率为胴体入库0～4h为30s/5min，4～10h为30s/30min；在该条件下采用雾化喷淋后，能够将预冷24h猪胴体的预冷损耗在春、夏、秋、冬四个季节分别由1.82%、2.11%、1.78%、1.7%降至0.93%、1.18%、1.11%、0.84% 。

Under the industrial conditions, traditional spraying has some problems that lead to a great chilling loss of carcasses. It’s necessary to take some measures to solve these problems. This study was designed to evaluate effects of chilling condition, season, spraying way, chilling time and some other factors on meat color, chilling loss, and aerobic plate count. The contents and results are as follows: 1. Factors of chilling loss Pork carcasses were selected in different seasons. These carcasses were assigned to different tracks in the same chilling room. The velocity, humidity, temperature and evaporative loss were measured. The results indicate that: The velocity, humidity and temperature of different locations had significant effects on evaporative loss of carcass (p<0.05). The location with high wind velocity had lower temperature, higher humidity and less evaporative loss of pork carcasses. As chilling time increased, the evaporative loss of pork carcass gradually increased (p<0.05). When chilling time was over forty-five hours, the evaporative loss of pork carcass was greater than 2.11%. The season had a remarkable effect on evaporative loss of pork carcass (p<0.05). In summer, the evaporative loss amounted to 1.76% after 24 hours chilling, which is higher than other season.. 2. Application of spray chilling system Under the industrial conditions, a new spray chilling system was applied and its effectiveness was compared with traditional spaying methods. Evaporative loss, aerobic plate count, water streak and color were measured. The results indicated that :The new spray chilling time had remarkable effects on evaporative loss, aerobic plate count, water streak(p<0.05).The optimal spraying time of chilling system is ten hours with 30 seconds at 5 minutes intervals for the first four hours and 40 seconds at half hours intervals for the next 6 hours. The new spray chilling system reduced the evaporative loss of pork carcass from 1.82%, 2.11%, 1.78%, and 1.7% to 0.93%, 1.18%, 1.11%, and 0.84% in different seasons（spring, summer, autumn, winter).