Ketchup Testing

1. Testing items
Microbial index testing: This is the key line of defense for food safety. It is necessary to test the total colony count, E. coli, mold and yeast, etc. If the total colony count exceeds the standard, it indicates that the product is seriously contaminated by microorganisms and is prone to food poisoning; the presence of E. coli warns of the risk of fecal contamination, which is extremely harmful. For example, the total colony count standard for high-quality ketchup usually requires no more than 10,000 CFU per gram.

Physical and chemical index testing: It covers the soluble solids content, which reflects the thickness and sugar content of the ketchup, affecting the taste and quality; acidity testing is equally important. The appropriate acidity can not only enhance the flavor, but also inhibit the growth of microorganisms to ensure the stability of the product during the shelf life. In addition, it also includes heavy metal content testing, such as lead and mercury, to prevent soil and water pollution from causing heavy metal residues and harming the human nervous system, kidneys and other organs.

Sensory index detection: The color of tomato sauce should be bright red when observed by professional reviewers. Dull or uneven color may indicate poor raw materials or improper processing; smelling it should have a strong tomato aroma without peculiar smell; tasting it, it should be sweet and sour with a delicate taste without bitterness and other unpleasant tastes.

2. Detection method
Microbial detection method: The total number of colonies is detected by the dilution plate method. The tomato sauce sample is diluted gradiently and inoculated on a specific culture medium. After a certain period of incubation, the number of colonies formed is counted. The detection of Escherichia coli uses the enzyme substrate method, which uses the enzyme-specific enzyme of Escherichia coli to decompose the substrate to produce a color reaction for determination.

Physical and chemical detection method: Soluble solids are measured with a refractometer, and the content is obtained based on the principle of light refraction; acidity is measured by acid-base titration, and the tomato sauce is titrated with alkali solution of known concentration, and the acidity is calculated based on the volume of alkali solution consumed; heavy metal content is accurately determined with the help of professional instruments such as atomic absorption spectrometers.

Sensory detection method: Under standard light sources and environments, professionals score and evaluate according to sensory evaluation standards.

3. Testing standards
In China, GB/T 14215-2008 "Canned Tomato Sauce" and other standards are used to comprehensively regulate the quality of raw materials, production processes, and finished products; internationally, CODEX STAN 57-1981 "Tomato Concentrate" provides a unified reference for international trade, ensuring that the quality of tomato sauces from different origins is comparable, safe and reliable.

4. Significance of testing
For consumers, strictly tested tomato sauces are safe and delicious, and can be used for cooking and dining with confidence to ensure healthy diets. For food companies, testing promotes the optimization of production processes, the selection of raw materials, the improvement of brand reputation, and the steady development of the tomato sauce industry, so that this red sauce will continue to light up the taste buds.