The antimicrobial effectiveness of cacao shell and cacao husk combination on inhibition of pathogenic bacteria in food products

Cocoa shell and cocoa husk are the waste from the processing of cocoa beans whose utilization has not been done optimally. The cocoa shell and cocoa husk contain phytochemical compounds which are potential to inhibit the growth of pathogenic bacteria in food products. The aim of this study is to find the ratio of cocoa shell extracts and cocoa husk extracts that most effectively inhibited the growth of Escherichia coli, Staphylococcus aureus and Salmonella sp. The method used experimental research followed by Randomized Block Design Factorial Pattern with 9 treatments and 3 replication. The treatment consists of two factors. The first factor was 3 types of extract (1:1, 2:3 and 3:2) and the second factor was 3 bacteria types (Escherichia coli, Staphylococcus aureus and Salmonella sp). The result showed that the extract mixture of cocoa shell and cocoa husk didn't provide interaction effects, but provided an independent effect to inhibit the various types of bacteria. The comparison of 3:2 w/w of cocoa shell and cocoa husk extract contain phenol 0.063% and flavonoid 0.0191% gave the most effective inhibitory effect on Escherichia coli with a diameter of inhibition zone 5.84 mm (resistant), Staphylococcus aureus 4.04 mm (resistant) and Salmonella sp. 21.00 mm (sensitive) and was able to reduce the total bacteria of Escherichia coli 7.67 log CFU/ml (6.19%), Staphylococcus aureus 7.06 log CFU/ml (13.65%) and Salmonella sp. 6.49 log CFU/ml (20.62%). Phytochemical tests showed that cocoa shell extract and cocoa husk extract containing phenol, flavonoid, triterpenoid, tannin, and alkaloid.