I plan on buying this. What do you guys think?:
http://www.hannainst.com/usa/prods2.cfm?ProdCode=HI%2099161&id=002002 (http://www.hannainst.com/usa/prods2.cfm?ProdCode=HI%2099161&id=002002)
I know its costly-- mainly because of the probe that they have attached to it. According to Debi and a couple of cheesemakers at another forum-- it costs almost $150 just for the probe alone!
wow, That is very impressive...
I have a probe with a stainless tip and ISFET chip for measurement and I'm a big fan of the probe-type food industry electrodes, although I haven't personally used the Hanna one. They're easier to clean and they don't get gummed up as much with proteins. Also the reference solution doesn't get contaminated as easily. I think it's a good unit, and should last a long time for you.
The GP probes are pretty cheap and that meter has DIN connectors so Hanna must sell the GPs on there site somewhere. Yes I did pay a pretty penny for the probe alone but it is worth it because I realy like to watch my fermented/dry aged sausages.
You can use this unit for milk, whey and the cheese once it has been pressed or do you need a different probe for each?
Troy, you can use any meter for the cheese from the milk stage all the way to customer ready. The difference is in ease of use, durability, and convenience... and longevity. For example, with a glass bulb round electrode, there all all sorts of nooks and crannies for the proteins to settle on, so your bulb may get dirty more easily than say a probe or ISFET chip probe with a tip. Similarly, the probes may differ on the type of reference solution they use (common is Ag/AgCl/KCl), and the material that the permeable membrane is made of that lets the reference solution pass through. Teflon or a composite material or an ultra high end ceramic is better than other types, for example. When electrodes fail, it is usually because the reference solution has become contaminated, or there is protein gunk covering either the bulb or the reference junction.
That's why a glass probe with a tip is a better choice; it's easier to clean. And that's why a refillable electrode is a better choice - you can usually degunk the reference junction, but it fouls up your solution, so you need to rinse and refill.
Some electrodes will use a gel KCl reference, which helps to prevent fouling, but of course once the solution is used up, unless you drill a small hole and refill it, the electrode is no good.
So to answer your question more directly, yes you can use it for anything. Remember to not store dry. Even an ISFET should be stored wet part of the time, or the saturated KCl reference will crystallize. If you do store dry, it's not the end of the world, but it takes 1-2 hours to revive the electrode. Almost any electrode can be revived. The one case where it's very unlikely is if the reference junction material is so gummed up that it's not letting ions pass through, or if the glass bulb is damaged.
Heh, look at their ad
"The electrolyte used in the FC 202D electrode is free from poisonous silver chloride, which eliminates food contamination by the electrode."
Yeah, they're technically right, the electrolyte is most likely a saturated ~4 M KCl, which is just a potassium salt. But the wire is an Ag wire, and has a thin layer of AgCl on it... that's how it works, and a very tiny amount usually makes its way to the food eventually. This is not a big deal, however. And they're right, it's not the same as using a straight AgCl electrolyte, but c'mon.... "eliminate"?
Guess I'm being nitpicky this morning.
[edit] read that wrong, thought it was a KCl reference, it's actually Viscolene.
[second edit] Wait, I was right, Viscolene is just a 3.5M KCl with AgCl. So is their contention that the open free diffusion reference junction completely eliminates AgCl from coming through? It's not material, but "eliminates"?
;D All about how you spine it right? LOL
I have decided PH meters make my head hurt. I have been reading about them and still know nothing. I want to buy a real nice unit, but there are lots of those. I also want to stay below $400.00 with probes, the unit and accessories.
Which unit did you go with?
I bought a surplus Oakton unit from ebay for $40 that has a BNC connector, and came with a bad electrode. I bought it for the base unit because it takes all kinds of electrodes, ones with a temp sensor and not. I reconditioned the electrode and it works fine now. Then I found some new, surplus Oakton ISFET probes with a stainless steel tip for $28 each, so I bought those as well.
I suggest because I think you'd want support from a vendor and a warranty (I don't need those that's why I went with cheap ebay stuff) to think about the Extech 110 that many have here. It's a small portable unit, unlike mine that has its own carry case, the tech support seems to be fantastic... to the point of shipping out a new meter with no questions asked, it has a flat electrode base, so you could take a soft toothbrush to it if it gets gummed up, the reference solution is a straight KCl, which is cheap, it measures out to .01, has 3-point calibration, and auto temp correction. Those are all important for cheesemaking.
If you went with a solution like mine that has a dedicated BNC, you'd still need to buy an electrode if yours ever went bad. With the Extech, you just buy the entire unit or a new electrode end for $50. But the entire new Extech is cheaper than many single BNC electrodes.
There are similar cheaper models, but I'm not sure about their tech support.
I have seen several post about the Extech 110 and it sounds good, but I am worried I am limiting myself going with a unit that will not accept BNC probes. What do you think?
Maybe I could just start with this one and if I decide later I want to upgrade I could sell it and buy whatever I want. Hmmm.......
So when we look at the Extech vs the http://www.hannainst.com/usa/prods2.cfm?ProdCode=HI%2099161&id=002002 (http://www.hannainst.com/usa/prods2.cfm?ProdCode=HI%2099161&id=002002) what does the Hanna have that the Extech doesn't? The ability to connect probes via the BNC of course, but what else?
Well, I'm not sure why you'd ever want a BNC connector. I have a lab set up, so I sometimes need specialty electrodes, so I bought a larger unit. Would you want to be able to buy an electrode that has a point tip so you could easily measure cured meats or pierce into a cheese? The latter could be helpful if you implement HACCP controls and randomly check samples of finished cheeses before sending them out. But you could do the same thing by taking a cheese trier, taking out a sample, and measuring pH with the Extech of the cheese on the end of the trier. If you're doing HACCP, you should be doing sensory evaluations with a trier, anyway.
That Hanna actually doesn't have a BNC connector; it has a DIN connector. It uses standard batteries that last longer. It lets you choose between standard or NIST buffers. Otherwise, they're about the same. Both have ATC, same pH and temp resolution, both are waterproof. The Extech is actually better in several regards because it has a cheaper, refillable electrode and stores more compactly. You can change out both the solution and the reference junction. One advantage of a probe is it may be easier to hold. The Extech is portable, but it's physically more compact and bulky.
I don't know... unless you're doing labwork, like checking thousands of cheeses, the Extech should be good enough. Can you think of a scenario when you'd want another type of electrode?
I did not think about using a trier...duh!
I just really meant a way to attach different probes. No I can't think of anything right now, but I am one of those freak that needs to be over prepared. I think the Army did it to me. I am glad we had this discussion because I can now buy the 110 and feel good about it. :-)
Thanks a million for your time! I have made about 30 pounds of cheese and plan to do another 8 this weekend. Trying to refine my process each time. I am going to be getting a curd knife so I can be more consistent there as well. Making cheese for my family to consume vs selling to the public is inspiring (requiring) me to get more technical with this. Hence the addition of the cheese facility, PH meter, curd knives, cheese vat, etc....etc.....
Truth is I want to produce something I will be proud to sell. I am a perfectionist, so it is a internal battle to keep my demons under control.
Have spent over half my day reading posts on this forum....Man I better do some work.
Sounds like you are well on your way. For commercial sales, log books and consistency are important, as I'm sure you know. Obviously because of repeat sales, but also for helping with issues like pathogen control. Would be heartbreaking to lose everything because of a lawsuit, and perhaps even worse to kill someone because of e coli or listeria. In the former, showing a log of proper pH and sanitation routines could really help. Because with food products, they can become contaminated later on in the chain, so if you can demonstrate proper handling, it's in your favor.
I try to have repeatable results for the simple reason that when I do start selling commercially, I don't want to be so tied to the farm that I can't leave. Want to plug in someone else and give instructions, and not worry about it.
Better schedule more time for reading :). Details are hidden all over the place that I haven't found in any book or class.
I was following along with this topic, because I am in need of a new pH meter. I bought a cheap pen-type that is failing on me already. I don't know a whole lot about the higher end meters, but the probe-type is something I wanted to start researching.
Quote from: linuxboy on March 24, 2010, 07:07:24 PM
Can you think of a scenario when you'd want another type of electrode?
I wanted to get a meter that would be appropriate for testing wine also. Would this need a different type of electrode?
No, this would work. For wine, I prefer a probe for the ergonomics. I usually put it in a beaker and put the electrode in and the cord hangs off to the side. Then I can take a reading from the base unit instead of trying to look at it on the handheld meter or recalling the reading from the memory. Just easier to work with on a table. For wine, having .01 resolution and accuracy is crucial, especially for must. You don't want to overadjust acid or TA because the reading is wrong.
Had an Extech 100 with a non-refillable probe. Extremely pleased with it, but the accuracy started drifting a bit too much for my taste and I was calibrating at the start of every cheesemaking session. Talked to Extech and they replaced the entire unit for free with no questions asked. Didn't even ask for the old one back. Their products are great and the customer service is amazing. Cheapo meters are just a waste of money.
I find that the cheapo (everything)s are a waste of money. Even if they last well enough, they don't have all the features I want, and I end up buying the good stuff anyways.
We plan to give a lot of cheese away and eat a lot in the beginning. We want to get opinions and make sure our product is solid before we start taking people hard earned money.
You know I do like the thought of having the base on the table next to the vat. I can see how trying to read it would be a pain. Still not sure it would justify the cost of the unit.
I do like this unit.
http://www.extech.com/instruments/product.asp?catid=40&prodid=447 (http://www.extech.com/instruments/product.asp?catid=40&prodid=447)
That's wonderful, Troy. It's what I always try to tell dairy people getting into cheese; focus on 2-4 cheeses and make them well, and sell the heck out of them. Some artisan people drive themselves crazy with 14 varieties. It's not bad per se, I just don't know how they do it and still turn a profit. Fun to experiment for oneself, but the marketplace out there in most cases is still interested in perhaps a dozen styles. You don't look credible if you have all those styles because people will think you can't possibly do all of them well. Most of the time, they're right. This doesn't exactly apply for flavored fresh cheeses like chevre, however. Do your specialties well, take notes so you can recreate them, and get out in front of as many people as possible and that's that.
I like to save my experiments or pieces vac packed for years at a time, and once in a while I'll open one up to see how its maturing. Cheese will keep for decades like that. If you have some space to store for longer aging, could be fun to do :)
I was in Vancouver last year and went to a market. There was a cheese vendor there who sold alpine-style raw milk cow cheeses. They had three styles, I think. Fantastic examples of the alpine tradition... very complex notes, layered flavors, could really tell the cows had no silage and were pastured only. They charged $7-$10/100g and many, many people were buying after trying the cheese.
Anyway, that's me on my cheese-selling soapbox.
You can still have the Extech on the table. Get a container of water, a container of pH7 solution, and a container to hold your sample in. Take a sample, put in sample container (like a small yogurt container, or a beaker if you have one), then rinse the tip of meter in water when done (under tap is fine), and put in buffer for temp storage. Keeps everything clean. The Extech keeps displaying the reading even after you take it out, so it's not terribly inconvenient. Have to rinse it off anyway, so you don't have to tilt your head to read it.
Quote from: linuxboy on March 25, 2010, 07:29:19 PM
That's wonderful, Troy. It's what I always try to tell dairy people getting into cheese; focus on 2-4 cheeses and make them well, and sell the heck out of them. Some artisan people drive themselves crazy with 14 varieties. It's not bad per se, I just don't know how they do it and still turn a profit. Fun to experiment for oneself, but the marketplace out there in most cases is still interested in perhaps a dozen styles. You don't look credible if you have all those styles because people will think you can't possibly do all of them well. Most of the time, they're right. This doesn't exactly apply for flavored fresh cheeses like chevre, however. Do your specialties well, take notes so you can recreate them, and get out in front of as many people as possible and that's that.
I like to save my experiments or pieces vac packed for years at a time, and once in a while I'll open one up to see how its maturing. Cheese will keep for decades like that. If you have some space to store for longer aging, could be fun to do :)
I was in Vancouver last year and went to a market. There was a cheese vendor there who sold alpine-style raw milk cow cheeses. They had three styles, I think. Fantastic examples of the alpine tradition... very complex notes, layered flavors, could really tell the cows had no silage and were pastured only. They charged $7-$10/100g and many, many people were buying after trying the cheese.
Anyway, that's me on my cheese-selling soapbox.
You can still have the Extech on the table. Get a container of water, a container of pH7 solution, and a container to hold your sample in. Take a sample, put in sample container (like a small yogurt container, or a beaker if you have one), then rinse the tip of meter in water when done (under tap is fine), and put in buffer for temp storage. Keeps everything clean. The Extech keeps displaying the reading even after you take it out, so it's not terribly inconvenient. Have to rinse it off anyway, so you don't have to tilt your head to read it.
And when testing the pH of the cheese/milk-- just testing and taking the sample from anywhere in the milk would be fine?
In almost all cases, yes. Some natural bacteria are bottom flocculants and some are top flocculants. Meaning they either settle to the bottom or stay at the top. In those cases, the lactic acid tends to be more localized and unless you stir everything up, unevenly distributed. So the answer is that assuming an even distribution of bacteria, taking a random sample from anywhere should give you a pH plot distribution that is within the acceptable margin of error for a calibrated meter. In other words, if you put the culture in and wait, and mix the milk about, you're fine.
Cheese testing is slightly different because cheeses age from the outward in, so you may have different pH levels in the middle than just under the rind. Depends on the cheese type as well. I check multiple points in a sample just to log more data, and if necessary, will emulsify and test the pH of the emulsion. This is overkill though. For aged cheeses, the pH is not a strong enough correlation of spoilage when doing HACCP, just one of the indicators. Proper checkpoint identification and design is more effective, for example.
I have this one and like it a lot. I also bought two probes a GP and a meat and cheese probe.
Here (http://www.sperdirect.com/cgi-bin/item/840087/pH/-pH-Meter---Basic)
I bought the meter from Amazon and the probes from Supply Cloud. I've only had it since June but I like it a lot. I got the probes in February.
Do you know who the supplier was for this, Deb? I bought an Extech on EBay and the supplier was Isopure--had nothing but problems with them and finally returned the unit. I need a meter, but prefer to buy from a company that is sweeter!
Sper Scientific sells the meter. Pretty reliable test equipment. The kit is cheaper in the long run but I miss read the Amazon ad. They did call to ask if I wanted probes also but I was way at the time so they just shipped what I ordered. I do like the little protective bottles on the probes - keeps them in solution and protects the tips.
This thread is making me want to upgrade my pH meter....
Hmmm.
Wayne,
Why would you want to upgrade your meter? What does your current unit lack that you would like to add in a new purchase?
Troy
Wayne just wants a BIGGER one. ;D
Quote from: TroyG on March 26, 2010, 02:49:39 PM
Wayne,
Why would you want to upgrade your meter? What does your current unit lack that you would like to add in a new purchase?
Troy
Maybe he wants one in which he could monitor and take the reading of an already made cheese in his aging cave. IDK.
That's the only reason why I looked past the Extech ones with the General probes and considered buying the ones with the point.
I also have meat-curing I could use this monitor for.
Actually, I am happy with mine. The price, the performance, and the reliability is just fine.
But all this talk of smaller probe, and an easy to read bench top readout, and the articulating arm.......
and it just looks cool. Better than my current layout.
I use mine for sausage more than cheese.
Wayne,
You can send me your setup and buy a new one. That looks great to me....Heck I don't even know what to do with that. LOL
Troy
Oh shoot!
did LinuxBoy ever get around to mentioning whether or not the spear-tip probe is attachable to the one Wayne, Carter and LikesSpace has?
Anyone know where to get one at? I looked at the Extech website-- but cant seem to find any like that.
No, it is not without disassembling the unit and attaching the probe directly or soldering on a BNC or DIN connector. The extech 110 requires its own special electrode that attaches directly.
If you want to get a spear tip electrode, you will need a base unit that matches up with it, either DIN or BNC.
I don't believe the extech does. I looked at them initally when i bought mine but couldn't get the probes without buying a different unit. That's why I went with the sper scientific and the BNC connector. They have another model (next one up) you can can printouts if you want.
So besides the 110 I need the following correct?
Extech PH103 PH BUFFER SOLUTIONS, 20PK INCLUDES PH 4,7,10,RINSE
Extech EX006 WEIGHTED BASE WITH 5 CUPS
Extech PH113 SOLUTION, REFERENCE REFIL (EXT-9126-E) FOR PH110