Apple testing

I. Testing items

Appearance quality: Check whether the fruit shape is straight, round, and deformed; the color uniformity and smoothness of the peel, whether there are traces of pests and diseases, mechanical damage, etc.

Internal quality: Test sweetness to measure sugar content; acidity to determine organic acid content; and water content to ensure juiciness of the fruit.

Pesticide residues: Test whether there are banned pesticides on the surface and inside of the apple to ensure food safety.

Microbial indicators: Test whether there are pathogenic microorganisms, such as Escherichia coli and Salmonella.

2. Testing methods

Appearance: Observe the shape and color of the fruit with the naked eye or simple tools, touch the texture of the peel with your hands, and check for damage.

Sweetness: Use a refractometer to measure the refractive index of the juice and deduce the sugar content; acidity is determined by acid-base titration, titrating the juice with sodium hydroxide.

Pesticide residues: Use professional instrument analysis techniques such as gas chromatography and liquid chromatography to separate and detect residual pesticide components.

Microorganisms: By collecting samples from the surface of apples, culturing and counting them in the laboratory, check whether the pathogenic microorganisms exceed the standard.

3. Testing standards

National standards: stipulate that the fruit shape is correct, the color is natural, the sweetness is not less than a certain value, and the pesticide residues and microbial indicators meet the food safety limit.

Industry standards: For different varieties of apples, the industry association refines the standards for subtle differences in appearance and taste, such as the redness range of the color of Red Fuji.

Enterprise standards: Some high-end brands have precise control over sweetness and acidity, and formulate internal enterprise standards that are higher than national standards and industry standards.

4. Significance of testing

Protect consumer health: Strict testing eliminates harmful substances, allowing consumers to eat with confidence and avoid the harm of pesticides and pathogens.

Regulate the market: Select qualified fruits according to standards and put them on the market, eliminate the disturbance of inferior fruits, and ensure the order of the market.

Help industrial development: Fruit farmers improve planting based on test feedback, and enterprises gain competitive advantages with quality, promoting the upgrading of the apple industry.