Accuvin Tests

[geocorn]

We have added the4 Accuvin tests to our product line. They include pH, TA, Residual Sugar and Free SO2. In addition, you can get the Full Pocket Kit which has all of the tests above plus Malic Acid.


The tests average around $2.00 each but are supposed to be easier to use and more accurate than some of the other products on the market. I am sending out the Full Pocket kit to 4 of the moderators for their evaluations.


For those in a hurry, we have decided to put them on the web site at introductory pricing. I would love to hear from any of you that have any personal experiences with these products.


BTW, they are on the testing equipment page.

 

[bilbo-in-maine]

Thanks George - didn't want to Have to go to the other guys for these...

 

[sangwitch]

yes, that sounds great. I purchased the "other" acid test kit recently and tried to use it, but gave up. The instructions are very ambiguous and left me frustrated. I have been looking at the Accuvin products and I'll be looking forward to the reports from the moderators.

 

[zonta223]

Hi
Anyone tried the Malic acid kit??
Tried it for the first time this vintage but it reads all the wines are dry (no malic) even if I test just after fermentation.


Anton

 

[K&GB]

I tested six kit wines that I have bulk aging yesterday, and I'm disappointed with the TA results. I ran 3 tests on all six wines: PH, free SO2, and TA. The TA tests seemed fine for the whites but I seriously doubt accuracy for the reds. The whites all tested around 7.5 (light green to yellow), but the reds were all 9 (orange). I suspect the color of the wine affected the results, but the directions specifically sayit doesn't. The reds didn't taste acidic, and the PHs weren't particularly low- 3.52, 3.68, 3.45. So I'm not sure what to make of the TA results.

 

[grapeman]

The TA tests are always a bit iffy with the color dependant tests. The most accurate method I have found to date and still cost effective for the small maker is to use the standard acid test kit. Instead of using the phenylthalene and adding NaOH until color change(which is hard to see in reds), you use a pH meter. The pH meters are calibrated and give very accurate readings. You can get the meters for about $40 and up and they last quite a long time.

 

[K&GB]

I'm going to try this tonight after work. Just calibrated my PH meter again yesterday. I remember you posted this once before. What's the expected value?

 

[grapeman]

Add the NaOH until the pH meter reads 8.2. That is the change point and when you would take the reading using the test kit. Go slow when approaching the 8.2- like around 7.9-8.0. It only takes another drop or two at that point.

 

[Bert]

You add the NaOH untill you get a reading of 8.2 on your ph meter.....toward the end , adding a small amount of NaOH will give you a big change in the ph...

 

[Bert]

You beat me to it Appleman..LOL

 

[grapeman]

I noticed that too Bert. Must be the jelly beans sped up my fingers- now how do I speed up this slow brain..........

 

[Bert]

I think I'm the slow one...only on my second cup of coffee...

 

[geocorn]

The kit manufacturers state that due to the consentration process, you can not get a meaningful TA or pH reading. I have had several customers adjust the acid based on their own tests and the resulting wine has been undrinkable. Save the testing for All Juice or fresh fruit.

 

[grapeman]

I second what George says about any adjustments to kits- THEY JUST DON"T NEED IT for acid or pH. They are good for the exercise to learn the process because you should have a rough idea what they will logically run. If you get a very high or very low reading, your process needs help because it should be within a fairly narrow range. The kit makers have adjusted acids to give the best final results. Don't overthink the kits. Nothing wrong with adding oak or things like that, but stay away from any large chemical adjustments.

 

[K&GB]

Two of my kits are MM All Juice, and one is an off-brand aseptic all-juice. I thought we were supposed to check PH and free SO2 periodically during bulk aging. The reason I was checking acid was because I plan to bottle my WE Viognier and my Heron Bay Sauvignon Blanc in three weeks. I'm one of the one's who mistakenly added acid to these prior to fermentation. Bitartrate crystals have precipitated out during bulk aging, and I wanted to measure the acidity prior to bottling.Tonight I plan to use my L.D. Carlson Acid Titration Kitalong with a digital PH meter and compare the readings to the Accuvin tests. I've never added acid to my MM All Juice Sangiovese or my CC SUper Tuscan or my American Winegrape Cabernet Sauvignon, but all three tested 8.5-9 g/L with the Accuvin TA tests.

 

[K&GB]

Thanks Bert/Appleman. I used my PH meter with the standard acid test kit and got values of about 7.5 g/L for the Viognier andthe Sauvignon Blanc. These readings match the Accuvin TA test readings. However, I also checked my CC Super Tuscan and got a reading of 7.5 where the Accuvin TA test was between 8.5-9. I really think the red wine distorts the Accuvin test results, despite what the directions say. Thanks again for teaching me how to use the meter. Takes the guess work out of reading a color change.

 

[Wade E]

You should check the S02 but there is no need to really check anything else with a kit.

 

[grapeman]

Well the reading of 7.5 is within the desirable range of 6-8 g/L for red wines. I guess it worked out well for you. Now you know if you want to check it for a blackberry or something, you can trust the readings. Good job.

 

[Steve]

I'm confused, are you supposed to check PH and TA on MM All Juice?

 

[K&GB]

Sorry, didn't mean to create confusion. I only checked acid on the two whites because I mistakenly added acid prior to fermentation (last October). That was before I knew better. I now know that kit wines come balanced with no need for testing or additions. But since I had already altered these two kits, I wanted to check them before bottling next month. While I had the test kit out, I went ahead and tested all six of the wines I have bulk aging. I was surprised to get such high readings on my three red wines, so I was hoping to get some feedback on the accuracy of the Accuvin TA tests. Edited by: K&GB