Effect of internal encapsulation process and external spraying process on survival rate of Bacillus subtilis and palatability of dog food

ZHAO Yiqun; YU Yuehui; CHEN Guo; XU Xue; ZHANG Zhi; CAI Xuan

doi:10.13557/j.cnki.issn1002-2813.2025.23.023

Abstract：The experiment aimed to investigate the effects of external spraying process and internal encapsulation process on the survival rate of Bacillus subtilis and palatability in dog food.The experiment used the external spraying process(group OF)and the internal encapsulation process(group IF)to add 1.0×1010 CFU/kg Bacillus subtilis to the dog food.The viable bacterial count,physicochemical indexes,and palatability of the dog food were measured after 90 days of storage under the conditions of closed bag at room temperature,open bag at room temperature,closed bag at high temperature,and open bag at high temperature.The results showed that the survival rate of Bacillus subtilis in the group IF was better than that in the group OF throughout the entire storage period.When stored in open bag at high temperature for 90 days,the survival rate of the group IF was 9.16 times that of the group OF.The two processes did not have a significant effect on the pH value of dog food(P>0.05).After 90 days of open bag storage at high temperature,the peroxide value of the group IF was significantly higher than that of the group OF(P<0.05).When stored at high temperature for 30 days,the vomiting toxin content in the group IF was higher than that in the group OF(P>0.05).There was no significant difference in the nutritional composition of the two groups of dog food(P>0.05).In terms of palatability,the average feeding rate of the group IF(56.93%)was significantly higher than that of the group OF(43.07%).The study shows that the internal encapsulation process can significantly increase the survival rate of Bacillus subtilis in dog food and improve its palatability,while the external spraying process performs better in inhibiting oil oxidation.