What can Greentest do?
Greentest can measure freshness of fresh fruits and vegetables and harmful substances inside, by determination of the relative nitrate ions concentration.
What does influence on the results of Greentest measurements?
The results of measurements depend on such parameters as salt concentration in the intercellular space, conductivity and the condition of the cell membranes of the tested tissue of a product.
What kind of contaminants (harmful substances) are measured by Greentest? Can the Greentest detect hard metals, pesticides etc?
Greentest measures the salts concentration in the tested products, both salts that are essential and the ones that can cause serious harm for your health. This is especially true for nitrate salts that can accumulate in the products in high concentrations, due to improper cultivation. Greentest is calibrated to show the number of nitrate ions only. Device is not intended to detect pesticides and heavy metal ions, as they don’t influence on the electric conductivity.However, the high level of nitrate content inside product may have a link to higher level of pesticides, heave metals, and link to lower level of antioxidants, microelements, vitamins.
Can Greentest indicate the freshness of fruit and vegetables?
Yes! Freshness is something that cannot be always detected by appearance. Some fruits are stored in refrigerator for months after harvesting, or with preservatives & chemicals added to make them look fresh. High level of nitrate may indicate the fruit is not fresh enough, because nitrate ions within the plant cells will gradually be released during storage when the fruits start to decompose. When food is not fresh, nitrate level will tend to rise. Freshness is related to potential bacteria/fungus level, a matter of hygiene and food safety.
Therefore, Greentest is also a convenient indicator of “Freshness”.
Can I use Greentest to measure water, milk, juce?
No, Greentest cannot measure any liquids. Using electric conductivity measurements, our device was calibrated on the fabric of vegetable products (taking into account their personnel characteristics), and not on the liquid/juice of the vegetables.
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Why does the second measurement of the same product provide different outputs? Sometimes I have 200mg/kg or more difference?
This variation is explained by the fact that the fruit/vegetable has a different irregular distribution of accumulated impurities in different parts. For example, closer to the stems of a product the content of impurities is much higher.
Please remember, to get more accurate results, you need to follow carefully the guidelines of manual and instruction “How to test”.
How is accurate the result of Greentest?
The accuracy of measurements is up to 90%, normally – in the range of 77,5%. It is proved by proficiency tests hold in metrology institution laboratories of China, Hong Kong and Taiwan.
Green, Yellow and Red colors of the result?
The limit numbers (green color) for every type of product have been provided based on European, American and Asian standards and suggestions (the references are provided in the manual – section 1.4). The yellow and red zones were set based on scientists’ suggestions and health organizations researches (it is more like a suggestion than a strict rule to follow).
What to do with a product that has red color result? Cook, eat, or throw away?
We do not advise to throw away if Greentest shows red, we only claim that if you consume all vegetables with mean concentration of high nitrate content for a long period then it will raise the risk of mentioned diseases, thus consumers are suggested to calculate their daily intake compared to their ADI.
This color should help you to determine where to buy and whether it is a right time/season to buy these products.
Mainly no fruits possess any threat because of low nitrate content. For vegetables there is no need to throw away as some food cooking and preparation procedures can lower nitrates by 15‐60%.
Here are some advices:
- Store the leafy vegetables in refrigerator if they are not cooked immediately;
- Cook vegetables soon after chopping or mashing;
- Wash and peel vegetables before cooking;
- Blanch high‐nitrate vegetables in boiling water for one to three minutes and discard the cooking water before consumption;
- Infant foods such as vegetable puree and vegetable congee should be prepared for immediate use.
Can I use Greentest to detect nitrate content in cooked veggies?
No. As Greentest was calibrated to detect nitrate ions only in fresh fruits and vegetables.
Does the temperature of food influence on measurements?
The products should be measured when they have the room temperature (at least one hour after storage in refrigerator), as any other deviations from room temperature in a product will highly influence on electric conductivity. The device measures electric conductivity but calibrated to show the amount of nitrates as there is a direct dependence with amendments attached to each type of product. All calibrations were made on products of room temperature only.
I change battery?
Battery cannot be changed, as the device cannot be opened. It can be charged with a USB cable. One charge is enough for 6 hours of continuous work and 1‐2 months for normal household usage. Device can be used for more than 3 years.
Calibrations and updates?
The device is calibrated every time when it is switched on. While switching on device, ensure that the probe is not inserted into the test product to exclude measuring parameters of the parasitic circuit for performing following product measurements. This enhances the measurement precision.
The Greentest cannot be updated via internet or any other source. The updated version that will have larger list of tested products and other features can be acquired only with a purchase of next new device with newer version of software.
How to clean the device, maintain sanitary and secure bacteria emergence?
Clean the probe with dry cloth before every measurement of tested product and with wet cloth after usage (before switching off device).