EVALUATION OF THE DEGREE OF SNAIL MEAT FRESHNESS BY THE PHOTOMETRIC METHOD

Abstract

This work focuses on developing a method of determining the degree of freshness of snail meat by means of a photoelectric photometer. For this, the absorbance was measured in filtered meat-water extract with Nessler’s reagent added. The method can be used in laboratories to determine the quality of meat of snails during their processing and sale. The results of using this method allow obtaining quantitative values when assessing the quality of snails of different degrees of freshness. A selection of 180 Helix pomatia snails was studied. They were divided into three groups, 60 snails in each, in accordance with the meat freshness degree. Three degrees of meat freshness were distinguished: fresh, questionably fresh, and stale. Meat samples were taken from all the snails of each group. Then the meat was ground, and 2.00 g portions were taken from each sample. 20.00, 30.00, 40.00, and 50.00 cm3 of distilled water were added successively to the weighed portions. They were infused for 15 minutes and then filtered. 0.50 cm3 of Nessler’s reagent was added to 3.00 см3 of the filtrate. The absorbance of the colour intensity of the meat-water extracts was measured with a concentration photocolourimeter extended in the range of light waves from 400 nm to 490 nm. It has been established that the highest absorbance indicates stale meat, the lowest is characteristic of fresh meat, and the value of absorbance for questionably fresh meat lies in between. Thus, when the concentration of snail meat extract was 1:10, at the wavelength 440 nm, the absorbance values were 1.243±0.031 for stale meat, 0.262±0.034 for fresh meat, and 0.804±0.054 for questionably fresh meat. This may be due to an increase in the ammonia concentration during the meat spoilage process. The three degrees of meat freshness were best determined at the wavelengths 440 nm and 490 nm. The results obtained are qualitatively and quantitatively in line with those of photometric studies of the freshness degree in beef, poultry, and fish.