Testing

The presence of infectious agents can be detected with a number of tests during the production and processing of meat, but testing by itself is not sufficient to ensure adequate food safety.The industry-standard Hazard Analysis Critical Control Points (HACCP) system provides for a comprehensive quality management framework as a part of which such tests can be conducted. The two quick method of detection of spoilage of meat are:

1 . Limulase Lysate Test:

• It is used for detection of endotoxinproduced by gram-negative bacteria based on a gelation reaction between lysates of Limulus (horseshoe crab) amebocytes and bacterial endotoxin.
• Limulus amebocyte lysate (LAL) is an aqueous extract of blood cells (amoebocytes) from the horseshoe crab, Limulus polyphemus.
• LAL reagent reacts with bacterial endotoxin and lipopolysaccharide (LPS), which is a membrane constituent of Gram-negative bacteria. This reaction is the base on the LAL reagent, which is then used for the finding and quantification of bacterial endotoxins.
• The Gel Clot LAL test provides very simple positive or negative result and is most often mentioned in international pharmacopeia monographs as the official test.
• Gel Clot assay is a qualitative LAL test for detection of Gram-negative bacteria endotoxins.
• The Gel Clot assay is run in tubes that are placed in a water bath or in dry heated oven at 37°C. After a one-hour incubation period, the tubes are flipped 180°. A firm clot that stays in the bottom of the tube indicates a positive reaction. If the liquid flows down the side of the tube, the result is negative for endotoxin.

2.Extra Release Volume:

• It 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 and 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 20oC 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.