Meat Science

ESTIMATION OF EXTRACT RELEASE VOLUME

• Extract release volume is the volume of extract released by a homogenate of meat when allowed to pass through the filter paper for a given period of time.
• It is inversely proportional to the extent of spoilage.
• Extract release volume is of value in determining spoilage of meat as well as in predicting shelf life of meat.
• In this method meat of good microbial and good organoleptic qualities releases large volume of extract while meat of poor quality releases smaller volume.

Apparatus required

• Blender
• Measuring cylinder
• Volumetric flask
• 10 ml graduated pipette
• Glass funnel
• pH meter

Chemicals required

• 0.2 M Potassium dihydrogen ortho phosphate
• 0.2 M Sodium hydroxide

Procedure

• Blend 15 gms of meat for two minutes with 60 ml of extraction reagent in a blender.
• Extraction reagent with a pH 5.8 is prepared by taking 50 ml of 0.2 M Potassium di hydrogen phosphate and 3.72 ml of 0.2 M Sodium hydroxide and the volume made up to 200 ml with distilled water.
• The blended contents are quantitatively transferred to a glass funnel provided with filter paper (Whatman No.1, 18.5 cm diameter).
• The filter paper is folded thrice so as to make 8 sectors and filtrate collected in 100 ml measuring cylinder and the volume of filtrate collected in 15 minutes at a temperature of 20^oC is reported as ml of extract release volume of the meat sample.
• The extract release volume decreases with progress of spoilage and a less filtrate will be detected in putrid meat.
• As per Pearson (1967), the cut off value of ERV in fresh meat is 17 ml and above.
• This volume is approximately equal to log 8.5 microorganisms per gram of meat.