Background – The current folate extraction methods for analysis in foods uses a tri-enzyme technique namely, addition of protease and α-amylase for hydrolysis of the protein and starch in foods to free the folate and a conjugase (chicken pancreas or human plasma or rat plasma) to further convert the polyglutamyl form of the folate to monoglutamate for determination using the traditional microbiological assay or the chromatographic methods. Given that there are high fat containing foods, the effect of addition of a lipase enzyme was investigated.
Objective – To assess the effect of the presence of inherent and added fat on the folate extraction from foods by modifying the existing method (Tamura et al, 1997) with the addition of a fourth enzyme namely lipase.
Design – Several foods under the Milk, cereal and meat category were analysed for folate with and without the addition of a fourth enzyme namely lipase.
The foods were purchased at least from three different outlets and homogenised in the laboratory using a waring
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blender and stored as composite samples at -20 C until extraction.
Outcomes – In the milk category, the amount of folate was on an average 71% higher (21μg/100g) when lipase was added than when only the trienzyme technique was used (6μg/100g) in cheese; processed cereal foods indicated a mean increase of 60% (20μg/100g) in croissant with added lipase; 71% mean increase in jam doughnuts; 75% mean increase in Chicken thigh; 68% mean increase in lamb loin chops; 85% mean increase in beef blade steak; 78% mean increase in tuna; 80% mean increase in egg yolk; 50% mean increase in potato chips.
Conclusions – The presence of fat in foods certainly interfered with the maximum extraction of folate in the selected foods, more so in foods containing inherent fat and further systematic studies on animal foods is warranted. Reference