Ecological desalination of anchovy residues and their mixture with soybean meal for the production of poultry feed: Optimization of waste through response surface methodology (RSM)

Abstract

Salted anchovy bones are a non-recyclable waste product containing high salt levels. However, they also contain valuable minerals such as calcium, phosphorus, potassium, magnesium, and nitrogen. This study aimed to find a cost-effective method to desalinate anchovy bones while preserving their nutritional value and repurposing them as a raw material for poultry feed. Through various tests, we were able to reduce the salt content of the anchovy bones from 15.4% to 4.7% using a 50/50 percent mixture of tap water and from 15.4% to 3.7% using a mixture of tap water and soybean meal in a 30/70 percent ratio. Combining soybean meal with desalted anchovy bones resulted in a nutritional composition comparable to that found in poultry feed, reducing salt content. The response surface method (RSM) was employed to determine the optimal proportions of desalted anchovy bones (70-90%) and soybean meal (10-30%) and to study the variables affecting the concentrations of NaCl, Ca, P, Ash, and TNM. The study revealed the influence of desalted anchovy bone and soybean meal percentages on these concentrations. This study demonstrates that the method used provides an ideal approach for understanding the interactions between input parameters (% DAR, % SM) and output parameters (NaCl, Ca, P, Ash, and TNM) and shows promising results for the desalination of anchovy bones using a soybean meal cake as well as the feasibility of creating poultry feed.