Determination of crude fat by acid hydrolysis

Determination of crude fat by acid hydrolysis

The word "fat" is a nightmare for many people in modern times. In an emerging era pursuing green, natural and healthy foods, the addition of fat has undoubtedly become a street-crossing rat. We hope that the food we eat, whether it is a snack or a staple food, is a low-fat, low-calorie food, so that we enjoy the food without worrying about unhealthy factors. So how do you know how much crude fat you have in your food and how do you choose foods so that you don’t have to worry too much about the troubles after eating? Here, we recommend some methods that I believe will bring you convenience. The crude fat analyzer is a professional instrument for measuring crude fat content in foods. It has a variety of models, such as SZF-06A Crude Fat Analyzer, SZF-06B Crude Fat Analyzer, and SZF-06 Crude Fat Analyzer. Different models have different power and specifications, but they are all capable of measuring crude fat content. In this paper, we mainly talk about another method of crude fat determination - acid hydrolysis.

Principle of acid hydrolysis: The sample is acid-hydrolyzed and extracted with ether. The solvent is removed to obtain the total amount of free and bound fat.

Acid Hydrolysis Reagents: Hydrochloric acid, 95% Ethanol, Ethyl ether, Petroleum ether, 100 ml stoppered graduated cylinder

Acid hydrolysis method experiment process: 1, sample processing: (1) solid sample: accurately weigh about 2 grams of water, add weight after mixing. Ml hydrochloric acid. Place in a 50 ml large test tube and add 8 ml; (2) Liquid sample: Weigh 10.0 g, place it in a 50 ml large test tube and add 10 ml of hydrochloric acid.

2. Place the test tube in a 70-80°C water bath and stir it with a glass rod every 5-10 minutes until the sample is completely digested, about 40-50 minutes.

3, remove the test tube, add 10 ml of ethanol and mix. After cooling, the mixture was transferred to a 100 ml stoppered measuring cylinder and the tubes were washed with 25 ml of diethyl ether and poured into graduated cylinders. After all the ether was poured into the measuring cylinder, the stopper was shaken for 1 minute, cautiously opened, gas evolved, and then plugged. Let stand for 12 minutes, cautiously unscrew, and use a mixture of petroleum ether and ethyl ether to flush the fat attached to the plug and barrel. Allow to stand for 10-20 minutes until the upper liquid is clear. Aspirate the supernatant in a constant-cone conical flask, add 5 ml of ethyl ether to the stoppered cylinder, and shake it. After standing, the upper layer of ether is still aspirated. Put into the original conical flask. The conical flask was placed on a water bath to dry and placed in a 95-105°C oven for drying for 2 hours. The flask was placed in a desiccator and cooled for 0.5 hour and weighed.

Acid hydrolysis method Calculation:

X=(m1-m0)/m2

X: the content of fat in the sample;

M1: Accepts the quality of bottles and fats, g;

M2: Accept the quality of the bottle, g.