Head of Litopenaeus vannamei, a low‐priced by‐product, was used to make fermented shrimp paste, Kapi, instead of the traditional raw material. The addition of garlic was hypothesized to prevent oxidation of unsaturated fatty acids, and tested by using garlic at 0%, 3%, and 5%. Decreasing aw was found in all treatments, while pH seemed to not change during fermentation. TVB‐N, TMA, malondialdehyde, and DH significantly increased with fermentation time. The addition of garlic at 3% and 5% seemed to retard lipid oxidation compared to the control case. After fermentation for 90 days, significant indole was noticed but no histamine was detected, while TVC and LAB of all treatments decreased. However, no pathogenic microorganisms were found. Likeness scores of all cases were approximately 6/9. Shrimp head can be used as an alternative raw material for making Kapi, but the texture and taste attributes must be improved in future work to meet consumer preferences.
Novelty impact statement
Shrimp head can be a substituted raw material to produce shrimp paste. Shrimp head paste with 12:1 ratio of shrimp head to salt and added with garlic at 3% can retard lipid oxidation in the product. Shrimp head waste is brightening for the prevention of authentic Thai dishes collapse due to shortening of shrimp paste.