Sohail Hassan Khan and Bashir Mahmood Bhatti

Abstract   

    The study was conducted to compare the effect of autoclaving, toasting and cooking processes on raw hatchery waste with shell and without shell. Average crude protein contents of hatchery waste meal (with shell) were 18.17% due to cooking and 16.83% due to toasting. Crude fibre contents were the lowest under cooking process. Crude fat contents were reduced to 11.44% by autoclaving. Total ash contents were increased substantially during all treatments. Calcium contents were reduced to 20% due to autoclaving. Nitrogen Free Extract (NFE) contents and metabalizable energy contents were significantly modified. Average crude protein contents of hatchery waste meal (without shell) and crude fat contents were significantly increased (P<0.01) under respective processes. Total ash contents were reduced due to removal of egg shell. Calcium and phosphorus contents were also reduced significantly due to removal of eggshell. NFE contents were markedly reduced when there were no eggshell. Energy contents were significantly increased when there were no eggshell. Overall, results of hatchery waste without shell were better than with shell. However, hatchery waste meal with shell is rich source of calcium. Within processing, there were non-significant differences for all nutrients with no Salmonella and E. coli Average acid values of cooked hatchery waste meal were increased significantly (P<0.01 ) from 3.04 to 7.88 after 9 months of storage. Amino acid profile of unprocessed hatchery waste (with shell), cooked processed waste with and without shell revealed sufficient quantity of all essential amino acids, particularly cooked processed hatchery waste (without shell) contained the higher levels of lysine and methionine. 

Key words: Hatchery waste, autoclaving, toasting. cooking, meal, chemical composition.