Jigger Testing

Jigger Testing


I remember learning the difference between accuracy and precision in high school science class (maybe Chemistry?), but I clearly didn’t carry that knowledge around for the following twenty years of my life. I’ve been using those words both interchangeably and improperly this whole time. In doing experiments that deal directly with these two concepts as well as a third counterpart of theirs (trueness) I completely neglected to use these terms. Instead, I made up phrases that described what I thought I was looking for. Luckily, I did a little digging and it turns out there were already words for exactly what I was doing—and they are:


Accuracy, and Precision & Trueness.

Do you know what these words mean, for real? I mean, could you define them to a group of unfamiliar people? Some of you likely can, but I’d wager that more than 75% of our bar population hasn’t the foggiest idea. I was one of those people just a few months ago, and I come bearing great news. These concepts are super cool, and deal heavily with what we do every day. I’m glad that I’m familiar with the terms, now. So glad, in fact, that the remainder of this article will be about what they are and why they’re important to me. 

Accuracy: the extent to which a given measurement agrees with the standard value for that measurement.

·   ie. If you aim to hit the bullseye, and your dart hits the bullseye, your efforts are accurate.

·   I take this to mean that if one’s effort is accurate then one is correct.

Precision: the extent to which a given set of measurements of the same sample agree with their mean.

·   ie. If you aim to hit the bullseye, and each of your darts hits the same spot on the board (whether the target or not), your efforts are precise.

·   I take this to mean that if one’s efforts are precise then one is consistent, whether correct or not.

Trueness: the extent to which the average of a given set of measurements agrees with the standard value for that measurement.

·   ie. If you aim to hit the bullseye, and each of your darts lands in the farthest four corners of the board, your efforts are true.

·   I take this to mean that if one’s efforts are true then one is correct, whether precise or not.


Accuracy refers to whether or not a single value is on target, while precision and trueness describe how accurate a group of values are. Courtesy of Wikipedia, the images below detail low accuracy as follows:

But what in the world does this have to do with us? Jiggers. Free pours. Drinks. The things of which we produce hundreds weekly for thirsty guests of our restaurants. We want our drinks to be consistent from instance to instance of the same drink. We would ideally like for each Margarita we make to be roughly (or maybe even exactly) the same drink each time. Your free-pour is as good as you can make it given the time of day, mood you’re in, music playing, and any amount of other things on your mind gunking up your internal clock. I have nothing against the free-pour necessarily, but I also don’t think it fits well into this exploration. The consistency of our drinks from instance to instance has to do with a variety of factors, but the one I’m most interested in is the measurement equipment we use.

The jigger! Everyone has their preference when it comes to this argument-starting tool that many find necessary, but few agree about which one(s) to use. Well, I was tired of having sensible arguments with cohorts about the effectiveness of each different style of jigger. There has to be a clear winner, at least in terms of pure measurement power, so here are the questions I asked on the way in:

1.     Do the lines on the jiggers accurately represent the desired volumes? Is the 1oz line actually showing an ounce? (accuracy)

2.    How great would the difference between twelve pours from the same line be from one another? Could the 1oz line pour the same amount each time? (precision)

3.    Would the average of the twelve pours from each line equal out to the volume the line purports to hold? (trueness)

On a .01g accurate scale, I placed each jigger tested and meticulously filled each line and side of the jiggers with water (no higher or lower than the line or the cup) and recorded their weight, which translates directly to milliliters, and could then be converted to ounces for my viewing pleasure. This was compared to the desired volume and that would represent the accuracy of the varying measurements on the jigger.

I then poured twelve pours from each of the markings on the jigger (so twelve in a row of .25oz, twelve of .5oz, twelve of .75oz, etc.) and recorded each of them in .01g accuracy in order to get milliliter figures for each individual pour. I took the difference between the highest and lowest pours for each target and compared that number to the target in order to find its precision, and then averaged the pours together to find the trueness of each target.

I performed these rituals for each line on each jigger tested, and eventually realized I needed to make an excel sheet of equations for this, as each set of jigger data were taking nearly twelve hours to compile and post. Due to the laborious nature of this I’ve only tested four jiggers so far, but now that the equation sheet is complete, I can re-post better organized results and test tons more jiggers!

I’ve used a gaggle of jiggers over the years, but the two most frequently used were Cocktail Kingdom’s Leopold jigger and Japanese jigger Duo. The Leopold jigger has the advantage of being an all-in-one tool, but the vast downfall of having a wide bowl. We use graduated cylinders rather than beakers to measure specific volumes, right? The shapes of the jiggers alone should be a clear indicator that the Japanese Duo will win in an overall precision battle, but do the lines on both jiggers actually read the volumes which they purport? In other words, are they even accurate to begin with? Results have been and will continue to be posted right here.

The conclusions I’ve come to are all in line with common sense, for the most part. Wider bowls are less precise, and each jigger has different starting points— by which I mean to say that some jiggers are marked incorrectly. The main conclusion to be drawn from all of this is that all jiggers I’ve come across do what they’re supposed to do. They measure booze and ensure some degree of consistency. Precise jiggers will make the same drink each time, true jiggers will make the right drink each time, and accurate jiggers will make a proper recipe drink each time. Ideally, we have all three of those qualities in one set of jiggers.

I know what I like to use, and I know why.

Knowledge is power! Can you defend your choices?

p.s. If you’d like to see a specific jigger type tested and posted in the same fashion as the others on my site, simply email me at itsme@donnyclutterbuck.com and I’ll try my best to do it! Onward and upward.

To Jigger What?

To Jigger What?

Jigger (n): a measure used in mixing drinks that usually holds 1 to 2 ounces (30 to 60 milliliters)*

[Free]-Pour (v): to [freely] cause (something) to flow in a steady stream from or into a container or place*


Many would say that only nerds use jiggers. Many would say that those who don’t use jiggers are ill-advised and careless. Manual or automatic transmission? Loft apartment or four bedroom house? On the rocks or up? It’s situational. We, as human beings, are self-proclaimed masters of classification and efficiency. We assess the best methods to suit our goals and we chase them fervently. Wars have been fought over differences in ideology since the beginning of human history. Luckily, we’re not in the midst of anything quite so serious here in the bar business—but, that doesn’t mean we don’t have some issues to work out amongst ourselves. Jiggers or free-pour? That is the question. Or at least a question worth considering.

            When properly used, jiggers are perfectly and scientifically consistent from drink-to-drink. They do take a bit longer to use appropriately than free-pouring, but the free-pour has issues with consistency. If you use a song to count your pours, such as—I don’t know—Billie Jean by Michael Jackson, your counts across a gaggle of drinks will be rather consistent, barring malfunctions in pour spouts or varying levels of liquid in the varying shapes of bottles. However, from the beginning to the end of a bar shift, the bartender’s heart rate will likely vary between resting and active BPM rates. I’ve personally recorded instances across 62bpm-115bpm in my own body on one shift (I had an Apple Watch for a few months—sue me). With a variance in heart rate over the course of many hours, with the addition of plaguing fatigue, stimulant use (coffee, cigarettes, etc.), alcohol use, or music and ambient noise levels, I’d say that this bartender’s perception of the world changes quite drastically throughout the course of even just one service. By this model, pours can be consistently shorter, consistently longer, or consistently inconsistent. None of these are ideal, and all of them are bad for someone, usually including the bartender.

            The jigger never changes. No matter the time of day, mood of the customer, or function of the POS system, the jigger is always going to measure exactly the same at 4pm as it does at 4am. Unfortunately, it’s still up to the bartender to use this tool appropriately. Low lighting can affect accuracy, as can a shaky transfer from jigger to glass. A chronic case of over or under-filling the jigger can have the same negative repercussions. Even if you’re the best at free-pouring, you’re still human, and you’re going to be wrong sometimes. Jiggering eliminates this issue when used properly. But, even if you’re the fastest jigger in the eastern USofA, you’re still going to be slower than a free-pour. So which of these two will reign supreme: the animal instinct, or the scientific imperative?

            Well, loft apartments are good for something entirely different than four bedroom homes, right? Neither is inherently better for everyone all the time. Skiing and snowboarding are a matter of preference as well, and while a manual transmission offers more control and fun, the automatic transmissions of modern times are more efficient and faster. I can’t say that any one choice is inherently better than another. We just have to find the best course of action to take within each situation we’re given. Our preferences change based on our situations in life, and our life situations change dozens if not hundreds of times per night during a bar shift.

            Maybe, just maybe, this isn’ta “jigger or free-pour” situation in which we’ve found ourselves. Maybe it’s a “jigger and/or free-pour” world. What a delight that would be! When you find yourself making one whiskey sour for your one customer at the moment, or a few cocktails for your few customers, a jigger may not be a bad idea if you’ve already got yourself a solid bunch of measured/house recipes. The drinks will be exactly as intended, and the sacrifice in expediency will likely be worth it for both you and the customer. If you find yourself with two Negronis, a Boulevardier, a Manhattan, an Old Fashioned, a vodka soda, and a gin and tonic for customers directly in front of you and the service tickets are piling up on a loud, dark, and busy Saturday night—possibly scrap the jigger. Those particular drinks aren’t the most sensitive, as even jiggering them while using varying brands of their prescribed ingredients will change their profiles immensely without changing the fact that they are, in fact, the drinks they’re meant to be.

            I’m not saying that we should sacrifice quality, necessarily. But at the end of the day, our jobs are about making the largest number of people the happiest we possibly can. There are moments where sending out 15 drinks in 6min that are an 8-9/10 will yield a larger amount of utilitarian good than sending those same drinks out in 14min at a 10/10. How many return visits will you get and from which method? Staunch opposition of either jiggering or free-pouring seems unreasonable at this point. Every foot is different, and it requires a different shoe.

            There are, of course, exceptions to this concept. There are some bars where jiggering just plain doesn’t make sense due to the bar layout and volume. I’ve never been behind this bar, but if you go to one you’ll understand. Conversely, there are bars where free-pouring would look silly and careless, and, dare I say, defeat the entire purpose of that particular bar. Every bar and bar customer is different, and they require individual assesment. If you work at a beer and/or wine bar, scrap this whole article! Sorry you read to the end-- but I guess that you may now have a different idea of how to arrive at the best possible course of action should you decide to delve into the cocktail world.

            My method is to read the crowd, read the customer, and act accordingly. I don’t make free-pouring a habit, but I most certainly don’t have jiggers superglued to my fingers. Each method neatly in its place makes for the best possible outcome, where I work.

What works where you work?


Jigger Testing Results

Working Under Pressure

Working Under Pressure

By Donny Clutterbuck

            I focus too much on anything I really like. I suppose the term “too much” is subjective, but safely I can say I’ve spent “too much” time investigating citrus juices, their acid content, ph, brix, and effective flavor lifespan. And I most certainly am not done. For the sake of clarity, when I use the term “citrus” in this article, I mean lemon and lime.

            I worked for ten years at bars that never juiced a piece of fruit. I worked at a few places that only juiced pieces of fruit, using no substitutes. I worked at a bar that not only juiced pieces of fruit, but would only use that juice for 24 hours from it’s juicing time. On and on through the bars, everyone had their own opinions about what the base level of must-haves are in terms of freshness and quality. I read books that reviewed juices’ flavor profiles over the course of time, and I found they agreed with this 24-hour rule for the most part. Knowing full well that wine degrades over the course of very little time, and that degradation is much due to oxidation, I began to draw parallels between wine and citrus juice. If the shelf life of a bottle of wine can be lengthened by a vacu-vin pump and stopper, then why in the world wouldn’t that work with citrus juice? Oxidation is an enemy in both cases, so even if there are other factors involved, we can at least stave that off.

            So, I did a citrus experiment with lemon & lime juices. They react similarly when exposed to oxygen. They both have a fresh shelf life of around 24 hours and show a lot of changes during those 24 hours. But, I found, if you vacuum seal fresh, strained citrus juice with vacu-vin wine stoppers, you can extend that usable shelf life to about 72 hours. That’s a massive increase in the time frame during which we can use the stuff, and it gives us a lot more leeway in case we’re not busy enough to use what we’ve juiced that day. Maybe you don’t change your juicing schedule, but you can postpone your next juice session? There are a lot of ways to use this information, but there might even be a better solution, depending on your bar program and how you use citrus.

            I went to the Nightclub & Bar Show 2017 in Las Vegas, NV. While on the trade floor, a friend of mine told me that there was a booth providing tastes of cold-pressed pineapple, grapefruit, orange, and LEMON AND LIME juices. I immediately discredited their business, calling it witchcraft and trickery and blasphemy and all that. I reluctantly navigated my way to their booth for a joke or two. I skipped the entire line of goods and went straight for the lime juice. I know how difficult succinic acid is to stop from accelerating browning, and how nice it is when lime juice is right! I took a sip of their cold-pressed lime juice, which had been squeezed I don’t know how long ago, but definitely longer than three days prior. I started skeptical, and I ended dumbfounded. How in the world did this lime juice taste any kind of good?

            Well, I still don’t really know. However, I wanted to see if this delicious juice—born more days ago than I’d have ever believed—would stand up to the same usability that fresh juice would. Industry Juice shipped me a 750ml bottle each of the lime, lemon, orange, grapefruit, and pineapple juices to taste test and ph test over the course of whatever time frame seemed reasonable. This was a ballsy move on their part, as a non-affiliated bartender could find something unsavory and release it, or release something totally untrue. I plan to do neither, and I don’t have to because I found nothing unsavory. What I found was astonishing to me. Truly.

            I received the order of juices Thursday 7/13/17 around 11:30am. Heading into a weekend of bartending, I wouldn’t have time to assess the situation until Monday afternoon, at which point, I realized I didn’t have any ph meter calibration fluid, which is ph 4 and ph 7 fluid by which to tune one’s meter properly. I ordered some and waited for it to arrive so I could begin my experiment. Well, it arrived that Thursday, so I wasn’t able to do much, going into another hearty weekend of bartending perpetually. Then yadda-yadda I got busy and couldn’t start the experiment until Wednesday 7/26. At this point, I’d already had the juice in my refrigerator for nearly two full weeks, and the purported juice expiration dates ranged from 9/21-10/6. This is important to the story.

            I popped the juices open, jiggered 1oz of each into five glasses small enough that the fluid would fully submerge the necessary parts of the ph meter. I waited five minutes for the temperature to stabilize closer to room temperature, then began taking ph readings. I left the ph meter in each fluid for one minute or more in order to allow the reading to stabilize, then recorded the ph level down to the hundredth with a presumed accuracy of +/-.03 for the equipment. I think it performed better than that, but I’d like to allow for that much wiggle room. After getting all the ph readings, I tasted through the juices from highest ph to lowest ph.

            The first taste of each juice was nearly indistinguishable from fresh fruit. The variablility between different shipments of fruit has been eradicated, as these are blended and standardized to the designated ph and brix levels the company has chosen, each bottle you open should be nearly identical to the previous, regardless of when it’s purchased. I repeated this process every day at 2pm for the following nine days, making for a total of ten. I stored the juices in their original bottles and didn’t vacuum seal them for storage. I simply put the cap back on and put it in the refrigerator. If I’d stored fresh juice this way, we can be sure that the lemon, lime, and orange juices would be spoiled within the first day. I can’t speak for the grapefruit juice and pineapple juice, but I can imagine their fate would quite shortly follow suit. Vacuum-sealed, fresh lemon and lime would last about 72 hours, and the orange juice would last maybe 6?

            Well, I waited two weeks to even open these cold-pressed juices, and they all tasted fabulous. Stored in a refrigerator without any vacuum treatment, they passed the three day mark with flying colors. This blew my mind. How could cold-pressed lime and lemon be coerced into cooperation when their fresh counterparts are so finicky? The orange juice also passed the three day mark. That’s right, the juice that normally lasts a few hours maximum has made it well past three days after being open in a refrigerator. In fact, orange juice lasted the longest! Here are the results I’ve seen from storing opened cold pressed juices with only the slightest bit of care.


·      Orange: 8/9 days

·      Pineapple: 8 days

·      Grapefruit: 5 days

·      Lime: 3 days

·      Lemon: 3 days

            So, cold-press treatment of juices stabilizes them within and without their bottle well beyond their original, fresh shelf lives. The benefits of these juices are I’m sure different for each bar, but there’s no debating their superior longevity. I look forward to doing another test or two with them. I wonder how long they would last if vacuum sealed, or better yet, if they were used in a kegged cocktail that uses nitrogen to push? If Could we potentially hot-batch a nitrogen-pushed, agitated, kegged margarita with the expectation that it might last a few weeks in there without browning significantly? There’s only one way to find out—and if you don’t do it, I will.


Technology pusheth forward! Future, ho!

Squeeze Your Juice Life


Squeeze Your Juice Life

by Donny Clutterbuck

           As more and more bars begin to prep their own fresh ingredients in house, each bar begins to develop its own in-house method of production and storage of each item. Quart containers, glass 750ml/1L bottles, or cambros? Electric or press juicer? For how long are the juices usable? While the storage method affects flavor as time goes by, it seems that it doesn’t affect the longevity of the juice. Plastic can impart its own flavor into the liquid, and the taste of whatever was in it before can leak in over the course of time as well. No one wants lime juice that tastes like onions, right? Juicing with a rotating electric juicer can pull too much rind into the juice and cause bitterness, and the peel oil doesn’t get expressed into the juice as it does when a press juicer is used.

            At Cure, we use a press juicer and store the juice in glass bottles. We find this to be the best method of storage, but how long does that remain usable, even in ideal circumstances? Not too very long, and the lifespan seems to be totally independent of production process or storage preferences. While most people won’t notice a big difference between 6hr and 36hr old lime juice in a Daiquiri, the difference is staggering when tasted alone and side by side. With the seemingly too-short half-life of lime juice, I began to wonder what specifically was making this reaction occur, and how we could stave the degradation for some more reasonable amount of time.

            We know that browning typically occurs due to the presence of oxygen, so my first inclination was to remove as much oxygen directly after juicing as possible. Here’s the experiment I conducted.


The Process:

-I purchased about three cases of limes from our distributor at the same time, to ensure as much consistency as possible, and kept them all in my home refrigerator at a constant temperature.

-Each day at 3pm for seven days straight, I juiced 150g of lime juice by squeezing into a quart container on a gram scale. After straining through a Cocktail Kingdom Coco Strainer, I funneled them into brand new, washed 187ml champagne splits and Vacu Vin sealed them. I labeled them with the date, and put them in my refrigerator-- knowing that they'd been squeezed at 3pm each day.

-On the seventh day of this, after the ritual 3pm juicing, I began to juice the same 150g every 3 hours until 3pm on the eighth day. I overslept one of my alarms by an hour, so I have a wonky time figure in there for the every three hours segment of this "show". You’ll see it in the below spreadsheet along the top as a 3hr, 6hr, 7.5hr, 12hr kind of inconsistency. Luckily, as you’ll also see, this was the time to screw up if there ever was one. There wasn't any drastic change during those times, and if anything, it proved that the sweet spot for lime juice is at least a little smaller than my planned intervals would've proven!

-At 3pm on the eighth day, I invited two barkeep friends over and we tasted through everything together and took notes. Here's a compilation of them:



1. Six hour old lime juice is the best, according (unanimously) a new, an experienced, and an old bartender. By this I mean people with 1, 3, and 13 years of respective bar experience. 

2. 1-3 day old vacuum-sealed lime juice is passable, though never quite as delicious on its own to our American palates as the six hour fresh juice. Even the vacuum sealed four day juice was alright, but it was beginning to go bad.

3. If you squeeze lime juice at your bar at 3pm every day, then your lime juice will be usable from 3pm-9am the next day, and it will peak around 9pm. If you squeeze lime juice at 3pm every three days then strain and vacuum seal it in glass bottles with Vacu Vin wine stoppers, upon opening those bottles right up to three days, you'll always have just post-perfect lime juice, and you'll have to juice/waste way less.

4. The acidity level of fresh and desirable lime juice hovers around 2.28ph, and as it begins to near the 24-hour mark, it drops to around 2.24/2.23ph. Every vacuum sealed juice over 24 hours old showed the same degradation, but without the milky, funky taste of the ph-degraded fresh juice. Maybe that's why none of the sealed juices tasted like the wildly-preferred 6hr old lime juice? This implies, most importantly, that there are two separate reactions occurring: a.) There's an anaerobic reaction driving the ph down independently of vacuum sealing, which drives the it after 21/24hrs. b. There's a separate degradation that brings the milky/funky taste that can be staved by a lack of air in the juice.

 FINAL: By vacuum sealing fresh lime juice, you never get the few hour window where the lime juice is delightful, but you always get it right afterward, and you can juice every two or three days. The point of this experiment was to find out how little we can reasonably get away with juicing, or how long we can get away with saving fresh juice-- but we found that there are at least two separate important reactions happening, and we can only push one of them back.

           Lemon juice has yeilded nearly the same product, and the results to more experiments will come over time at www.donnyclutterbuck.com, and I’ll make sure to include them in these blogs as they come up. We can get away with juicing just a bit less, if we so choose—and we maybe don’t have to immediately throw away unused lime juice. We never know exactly how busy we’ll be on a given night at a bar, so any leeway we can give ourselves is important.

A little food for thought—to make our lives just a TOUCH easier. Keep it real, y’all.

Juice Test Results HERE!