I suppose the refractometer market is kind of like the cell phone industry but with fewer manufacturers. I guess I’m glad then to see that Atago has not taken it’s foot off the accelerator when it comes to improving their products. Take the newest RX-5000i digital benchtop refractometer. It does not cost any more than the previous models, the RX5000alpha and the RX5000plus. Huh? Why? I think Atago wants to stay ahead of the competition by delivering a better product. So the new RX-5000i (and 5000iPlus) Digital Benchtop refractometers now have an improved user interface that incorporates a touch screen with seemingly easier navigation and operation. We will have to see how customers respond to this and let everyone know once the units have been out for awhile. Still, I do think the improved temperature range and the delay as well as the USB interface will be well received by customers.

You might be thinking, so what. I would probably agree with you but have you seen the news recently about oil spills? How about the one that just happened in the Gulf of Mexico? Since oil is less dense than water it floats. Look out Florida, Alabama, Mississippi, Louisiana, and Texas!

Liquids have different densities and will not mix if the difference in densities is great enough. Temperature is an important factor that can affect a liquids density too. In general, as liquid temperature increases, density decreases.

As you might expect knowing the density of a liquid serves numerous purposes and can provide valuable information for making decisions. Density can tell you how much sugar is in a can of soda, or how much gasoline and kerosene is in a petroleum product, or even aid someone in predicting how two or more liquids will interact. Understanding what density is, what affects density, and how density affects other physical properties is also important in using and translating this information into an everyday useful tool.

We live in a physical world and so it would make sense that we would want to be able to define these physical properties around us. Having a way to define these physical properties is helpful to those who need to use the information.
• How much space does it take up?
• How heavy is it?
• How much of this can we put into that?
• What is it?
• Many everyday products are packaged by volume but sold by weight
• Fluid properties; predictive correlations can be made if you know the density
• If we change some of the ingredients that make up the fluid property will it change the weight?

The neat thing about understanding liquid density is that it can answer not only the three basic questions; What is the mass (weight) of the liquid?, what is the volume of the liquid? What is the density of the liquid? But also, what is the liquid? Yes, we can actually compare liquids to grade and categorize them using a term known as specific gravity.
If you found this interesting stop back again as we explore further…

Today we thought it would be fun to speak with someone who really knows the sport of wrestling and discuss some of the “science” behind the jockeying and positioning that goes on in the sport.  Realizing that body weight is a primary factor that can leverage or influence the outcome of a match begs the question,   … ” how far will a wrestler go to maximize their advantage?”

Is losing weight always healthy?  What practices do wrestlers use?  What are the side effects?  What are the risks?  What can we learn from science today to help the sport and the athletes?  Can wrestling be more competitive and safe?

LISTEN to this 28 minute podcast with guests John Allman and Eric Kostenbauder.  John has about 30 years of wrestling experience both as a wrestler and as a coach.  Eric has also wrestled and has experience with some of the testing requirements we see today in the sport.

PODCAST TIMELINE:

-Introduction

-Wrestling/ the sport

-Wrestling practices/training

-Making weight

-Testing body fat and testing hydration

-Urine Specific Gravity

-Peer pressure/monitoring reasons and techniques

-Refractometers; “Pen Wrestling” handheld refractometer

-Reasons for testing

-Making it safe while educating wrestlers

Coach John Allman

After all of the sample has been injected immediately pull the needle from the vessel septa port and go directly back to the analytical balance to re-weigh the empty syringe.  Weigh the empty syringe and write that number down- this will be weight#2.

When the karl fisher titrator finishes and indicates that the test is complete the titrator should prompt you to enter weight#1 and weight#2.  After inputing both weights the karl fisher titrator will calculate the results for you.

Hope this is helpful.

H

If you would like to see this process you can watch it here:

Listen in and learn more.

Hope it helps!

SG

Atago has just created a new series of refractometers that can be dipped into the the testing medium and then simply rinsed with water afterwards. With the Automatic Temperature Compensation (ATC) the pen will enable you to take accurate measurment readings regardless of the ambient temperature.  They say that now operators can have a  “Continuous Measurement” feature to expand current measuring methods.

The Brix range is 0.0 to 85.0% with an accuracy of Brix± 0.2%.

Atago is marketing this device towards those that work with samples that require continuous testing where the operator can move from one sample to the next very quickly.

We are preparing to do some real world testing and will post the results and the video here, so please stay tuned if you are interested.

Joe Levi

I don’t know at what age I started eating Yams but I do remember as a child I would often help my mother around the holidays serve a baked dish of orange-looking potatoes (sometimes with marshmallows on top).  I never knew if I was eating a sweet potato or a yam.   Actually I always thought they were the same thing.  This is a terrible thing to say considering I grew up in IDAHO!   You think someone would have had me in a POTATO 101 class by third grade.

potato, sweet potato, yam

The fact Is that sweet potatoes and yams are two different vegetables.   A true yam is the tuber of a tropical vine and is not even distantly related to the sweet potato.  Yams are generally sweeter and contain more natural sugar than sweet potatoes – and have a higher moisture content.

Now I don’t suggest you do this around dinner time but If you are ever in need of checking this and comparing sugar content you may want to use a brix meter.  It’s probably more appropriate for those of you who are expert chefs, and or someone who is growing, picking, canning, and or processing yams.  If so, a handy tool is the Atago PAL-1  “pocket” refractometer.  This device can measure Brix 0.0 to 53%, which is adequate for yams.

Using the PAL-1 refractometer (Brix), there are basically two different ways to measure the Brix of baked yams.

1. Cut a baked yam in half and gently push the prism of the PAL-1 refractometer against the flesh of the yam.  It is important when doing this to make sure there is no air between the yam and the prism.
2. Grate a raw yam, strain it, and then measure the juice.  It is however recommended to cook the yam some as the starch in the yam can vary results.

With the holidays approaching I thought it would be fun to write about something relevant!

h

We received a recent inquiry from a customer and thought the answer would be beneficial to others. The customer asked: which refractometer is best for milk?

Well, that depends on how you are going to use it. In some countries, there is a need to measure the concentration of solids in milk to determine if there has been any accidental dilution. For this use, companies produce a refractometer specifically designed to measure milk solid levels. This “milk unit” has a range specific to milk and compensates to 15°C, a common milk temperature. The unit can also be used as a way to measure cow health, which is more applicable to the needs of those in the United States. But if you’re looking to use a refractometer on milk for more casual reason, the PAL-1, a standard hand-held unit, would be the most practical. It can be used on a variety of substances and have a larger range, and is therefore more versatile. It all depends on what you want to do!

We are always on the lookout for people who can use the technology we have to offer and I came across a very interesting forum where users discovered a way to determine the strength of a coffee sample.

I contacted the author and he gave me permission to post the article here.

Subject: Measuring Coffee Strength With A Brix Meter Pal-1

- Alan Alder, Palo Alto CA.

Do you enjoy tinkering with grinding and brewing techniques?   Do you have about $270 to blow on your coffee hobby?   If not, this isn’t for you. But if so, read on.

While developing the AeroPress, I needed a method to measure brew strength.  I first tried the SCAA Total Dissolved Solids (TDS) meter but found the results inconsistent.   I called SCAA and discussed it with their Technical Director, Joseph Rivera.   I mentioned that I was an electronics engineer and thought that the TDS meter, which is simply a conductivity meter, was too sensitive to small variations in saline content of the water or the finished brew.   Joseph agreed and said that he had heard that someone was using a Brix meter.

A Brix meter measures index of refraction and is normally used to measure sucrose level of liquids such as juice or wine.   A Google search for Brix and coffee measurement came up empty, but I decided to give it a try and bought a $270 Atago PAL-1 digital Brix meter. It turned out to be the answer to my needs.

To measure brew strength with a digital Brix meter you put a few drops of brew on a small glass window and press the button. Voila! A reading appears. No calibration baths or other annoyances.   It fits in my pocket and I can take it from my lab to a coffee shop whenever I wish.

After using Brix for about a year, I took it to the SCAA Convention in Seattle last April and showed it around.  One of the first people I showed it to was Joseph Rivera.  A few months later, he bought one himself and is now a confirmed Brix user.   He also told me recently that his dehydration instrument verified that Brix is far more accurate than the old conductivity meter they sell.

Another person I showed it to was Randy Pope of the Bunn Technology Center.  Randy pulled out his own Brix meter and told me that he’d been using it for eleven years and that it was very accurate.   He also shared measurements he’d made to correlate Brix to Total Dissolved Solids as measured with his dehydration instrument.  He found that 0.85 x Brix equals the percent Total Dissolved Solids (TDS).

The SCAA recommends 1.25 percent TDS for ordinary brewed coffee.   That corresponds to 1.47 Brix, which the meter rounds to 1.5.  There is no standard for espresso, but I’ve measured hundreds of shots and find that most are in the ranges from about 3.4 for pod and capsule machines to about 7.5 for professional pulls.   Here are some measurements that I’ve made:

1.5 Krups drip brewer with paper cone filter

2.1 Brewed coffee at Peet’s – Los Altos, California

3.4, 3.6 Nespresso capsule brew

3.7 Victoria House concentrate

4.8 Starbuck’s, Los Altos

4.4 Filtron cold-brewed concentrate SCAA booth

4.9 Solis automatic at Baratza SCAA booth

5.2 Ken Davids’ Saeco Vienna (Summer 2004)

5.3 Ken Davids’ Saeco Vienna July 25, 2005

5.9 An old Italian lever machine

5.6 Rancillo booth at SCAA

7.3,7.4 Pasquini Riviera machine

7.5 Peet’s, Palo Alto, California

20.6 Cafe’ Vivace, Seattle

The last reading is unusually high and the product of espresso-guru David Schomer, who clearly likes a very intense shot.

My own taste buds prefer about 7.5 for straight espresso but I make it stronger when making a shot that will go into a latte.   Of course I brew my shots in an AeroPress, which can make any Brix I want, even up into the twenties.

Here are two tips on Brix measurement of coffee:

1. The meters is temperature sensitive.   It can take about a minute for the sample to cool enough to give a stable reading.

2. Brix is primarily a method of measuring sucrose level, so there must be absolutely no sugar in your sample.

After measuring the Brix level of hundreds of samples, I developed this formula:

Brix is approximately equal to K times (coffee weight) / (water weight)

K equals about 23 for an AeroPress using fine drip grind and 175F water — which is everybody’s favorite AeroPress temperature.

K increases to about 27 for a conventional espresso machine which uses both finer grind and hotter water.

It’s easy to weigh the input coffee and input water with an AeroPress, but more complex with a conventional espresso machine.  Barry Jarrett asked me how I do that.  Here is my answer:

Weigh the empty portafilter.

Add and tamp coffee, weigh it again and subtract empty portafilter weight to get dry coffee weight.

Weigh the output cup.

Pull the shot.

Weigh the cup of brew and subtract empty cup weight to get brew weight.

Weigh the portafilter containing the damp puck and subtract empty portafilter weight to get wet puck weight .

Input water weight = brew weight + wet puck weight – dry coffee weight.

You can also use a formula based on coffee weight / brew weight.  That’s simpler with a conventional espresso machine and the formula is about:

Brix ~ 18 times (coffee weight) / (brew weight)

I also find Brix to be an excellent tool for evaluating grinders. If the grind isn’t as fine as claimed, the brew will be weak and the Brix low. All the cheap burr grinders I’ve tested fell far short of the formula, even on their finest setting.

As I said in the beginning, Brix isn’t for the casual barista.   But if you’re a Mark Prince, or Barry Jarrett or David Schomer, after you try Brix you’ll wonder how you ever got along without it.