QuantiQuik™ Malic Acid Quick Test Strips

RT

What samples have you tested?
The strips have been tested on red wine, white wine, homogenized whole milk, cultured buttermilk, almond milk, yogurt, beer, apple juice, lemonade, grape juice, orange juice, cranberry juice, lime and lemon juice.

My sample turns the strip very dark purple, how can I determine the D-lactate concentration?
Very dark purple indicates that the diluted sample concentration is greater than 500 mg/L. To obtain a more accurate concentration, the sample should be further diluted and retested. For example, if the sample was diluted 5& times, try diluting 21x.

I don’t have access to a pipetteman. How can I accurately measure out my samples?
We offer exact volume transfer pipettes as an accessory. For samples requiring a 21x dilution, order the 20 uL transfer pipettes (TP20). For samples requiring a 5x dilution, order the 100 uL transfer pipettes (TP100).

In your product information about the QuantiQuik L-Lactic Quick Test Strips, you indicate that there is information on how to prepare yogurt products for analysis with the Quick Test strips. How do I prepare my yogurt sample?
Previously, we have tested the QQLLAC test strips with greek yoghurt and buttermilk. Since yoghurt is a solid sample, it cannot be diluted in the same way as liquids, so sample spoons with defined volumes were used to measure the amount of sample to dilute in water. If you have access to a scale, you can also weigh out your sample. Our yoghurt required a 5x dilution, but different samples may vary.

I am working with Sour Beer samples and the edges are dark purple while the center is pale yellow. Is this normal? I tried D-Lactic & L-Lactic and had similar results
The color on the strip should be uniform. Sometimes the strip will not develop a uniform color if the sample is too acidic, and I suspect that this is your problem. In this case, you can either dilute your sample further than 5x, or if you have access to pH measuring equipment and a strong base like NaOH, you can adjust the pH of your sample to ca.7 and rerun the sample.

Can I store unused reagents for future use?
Yes, unused reagents can be stored according to the assay protocol. The strips should be kept in a dry, cool location and protected from light.


For more detailed product information and questions, please feel free to send an inquiry to info@hoelzel.de

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