Do I really need to worry about SG?

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Aug 16, 2009
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When I started making beer around 1990 the store owner who taught me to brew told me I really didn't need to worry about SG and that I would still make great beer. So I Relaxed and Had a Homebrew for about 20 years and never took a single SG reading. I was bottling and kegging as fast as I could because I had plenty of friends that enjoyed my brews. My primary was constantly bubbling away. I'd start new brews on top of the yeast in the bottom of the carboy and be fermenting my next batch in no time. I made beer that I didn't care for but none that I would say were off because I didn't take SG readings. I don't like Coors Light but it has nothing to do with SG readings.

I made my first wine in 2004 when I moved into my new house. I was hot and heavy for about 10 years and again never took a single SG reading. In all that time, I can only think of one batch of wine (The Holy Wine) that wasn't worth drinking. Can't recall 100% how it happened but a bible somehow fell into my bottling bucket as I was syphoning the finished wine into the bucket. I fished out the bible and bottled the wine but it was ruined. But, I digress. I made Island Mist up to LE Wine Expert. I did multiple rackings and bulk aged most of my wines and ended up with crystal clear well polished wines that quite frankly tasted good.

My kids got busy with sports, I bought a business and PA started getting some OK wine in their stores, so I got out of the hobby for a while. Just did some work on the basement and made a new area down there for me to start fermenting again. I'm waiting on an RJS En Premieur Pinot Grigio to arrive. Hopefully I'll have it in the fermenter next weekend. So after all that, we get down to the question. Do I really need to take SG readings? What benefits will I see from doing so? While I'm no longer off to baseball and lacrosse games, my business still occupies a lot of my time. I produced good beer and wine without SG readings. Will I realize any significant benefits from doing so now that I'm making my 2nd foray into this wine hobby?

Looking forward to filling up the new bench with multiple carboys of fermented grape juice. Going to get some of the wines that benefit from longer aging going and then fill in behind them with bottles that get to the glass quicker. Hopefully by this time next year my wine rack and wine fridges will be overflowing. Thanks for listening and thanks for you input.
@kiphorn , when doing kits, an experienced winemaker can easily get away without taking any SG readings. There are some decent reasons to take SG readings when making kits.

Taking one before you start will ensure that your kit is not off in some way, it also gives you the opportunity to boost the SG / ABV if you decide to do so.
Knowing the starting SG and final SG allows you to determine the ABV of your finished product.
Knowing your SG along the way allows you to monitor your fermentation progress.
Its really quick and easy.

Those are a few of the major reasons. In my case, like you i haven’t taken a SG reading during fermentation in a long time. I’m comfortable with the process and can see / smell / identify issues without one. I do, however, always take a starting and final SG.
To me starting a wine without taking an SG reading is a bit like buying a new car on the phone without looking at it and driving it in person. You know what it is advertised as but in reality..... this one could be a lemon or have all sorts of issues you need them to fix before you drive if off the lot.
Readings along the way, Since I don't do kits, I may have issues with the must or the yeast that I didn't notice so during fermentation I take readings to know how it's progressing, and to know when to do my step-feeding if I am going to do that.
1) a beverage with 5% alcohol will resist a lot of bacterial infections, and pushing up to 11% works as a preservative so you don’t worry about food poisoning, ,, as a top limit 18% will kill off yeast
2) alcohol will affect the flavor balance, by itself alcohol is sweet so more is sweeter and requires more acid or tannin for balance, ,,, you can tweak this on the finished wine also
3) shelf life, meta works better with more alcohol
4) legal, labels have to be accurate to half a percent
5) consistency especially if fermenting other than grape where sugar is all over the place

all in all as a home wine maker who drinks young wine it doesn’t matter much
all in all as a grape fermenter product is quite consistent and it doesn’t matter much
for kits the work has been done for you and a SG reading is not necessary just cautious
for other wines grape or fruit, the winemaker must decide if the product will be worth while the sg along with ta and ph readings are required. other wise just wasting your time
I'm with Scooter68. I don't make kit wines either. I only make country wines and my own home grown muscadine wine. When preparing the must, a SG reading is important to make sure that the gravity is not beyond what the yeast can tolerate. Taking an OG and a FG for me is of the utmost importance to ensure that I am adding the correct amount of sugars to the must to obtain the level of ABV that I'm looking for. Also taking a SG once fermentation has stopped allows me to make sure that the yeast fermented to completion and not became stuck. This might be the most important reading of all.
"Stuff Happens" Regardless of the consistency and legal requirement for products to conform to label statements, Taking an SG reading takes just a minute or two, Don't know why it wouldn't be worth that small amount of time before starting a ferment to know that what is on the label matches with what you in fact have. IF a product has a lower or higher than expected reading, you can adjust it, before starting the ferment. After it's started or finished you have no way (without a lab test) of being certain that you did in fact get what was on the label. After all a kits costs more than most food products folks buy and the time invested is not a small amount.
I know this sounds like I'm being contentious, not my intent, but; If I've spent $50.00 - $180.00 I want to be sure that I what was delivered is what I ordered. I'd spend the tiny amount of time to confirm that. During fermentation - that's strictly personal preference, but starting and final SG seem like a reasonable step for most folks.
To me if you own a hydrometer why not take a reading? And why not just leave the hydrometer in the bucket during the primary fermentation (and keep it in for secondary as well if you are transferring to secondary before you reach terminal gravity aka FG).

The first SG reading is the OG in beer lingo, the more important ones are the SG readings you take at the end to see if you are truly at your terminal or final gravity (FG), having the two (OG and FG) will give you your ABV. Having the ABV is not terribly important, but knowing that your FG is .995 or lower, not a stuck ferment at 1.000 is invaluable.
I guess my only question is why not? It's free except for the minimal cost of the hydrometer. It's not time consuming. You can be sure of your ABV - well close anyway. And you know when to get it off the lees, and when it's done.
I agree with above. It’s what we do. Part of the hobby. Verify your instincts. I tend to do a lot of fruit and botanical wines. However when I do a few grape wines (either kit or fruit) I most certainly do check both pH and Brix. my theory is ‘I want to know'. And guess what - I found pH was really off on a Sangiovese kit some years back. So I sorted that with some tartaric acid then proceeded to pitch the yeast once the pH came into line. Ref Your beer brewing - I make a couple of kit beers every year to shut my kids up when they come home for family festivities. Along with the kit supplied pre-prepared wort, I use liquid malt extracts as a sweetening fermentable agent - and interestingly the %abv is normally between half to one percent higher that the claims made on the preprinted packaging. So my brewing friend - I can only suggest you enhance your brewing and fermentation technique and start taking either the Brix or direct specific gravity readings off a hydrometer. It makes our hobby a lot more fun. all the best.
I am not a kit person. Never made one. I guess it is not completely necessary for a kit, if you trust the kit maker. However as someone else stated, it only takes a second to take an SG reading, so why not do it? There are several reasons to check it, but in my mind, the most important reason to check it - for me - is to see what my potential alcohol is going to be as not to stress the yeast. It is also important to know when determining if fermentation is complete. A hydrometer is cheap and and it only takes a minute or two to check SG. So, again, why not check it? It is surely a personal choice. If you are happy with your results without the measurements, then don't worry with checking it.
Venatorscribe's comment about the pH of a kit being off - We only hear about product recalls when the is a SERIOUS health threat/potential to the public. Many other products are delivered with problems that are just not a threat to our health but may significantly lower our enjoyment. They don't issue recalls for cans of soda or brew that arrive on the store shelf flat with no carbonation. They simple pull them back. And that problem may well have been discovered by a customer before any plant testing finds it. My mom (over 50 years ago in the 50s in fact) found a piece of metal in some store bought bread. She called the store and it was amazing. Apologies, several loaves of free bread and coupons as I remember. Stuff Happens.
Last week we opened a package of mozzarella cheese and immediately found the old blue mold on the better part of one end. I checked the date and it was over 6 weeks before the "Best By" date. So, stuff happens and when we are making wine, or beer or what ever, we are the last line of quality check to make sure that what we are producing is going to be what we want and expect it to be. 11% ABV vs an expected 13% - not a big deal normally. Low pH, well that could serious affect the longevity AND the taste of the wine.
We have those tools for reason why not use them?
When I made wine from grapes, I took SG reading so I would know whether or not I needed to chaptalize. I could have also used a refractometer, but I didn't have one. Today, when using kits, I am interested in SG to know when to quit adding water; kits do not always make 5 gallons or 23 liters.
Thanks for all the thoughtful replies and good information. It sounds like I need to do some reading to learn how to take the readings and then what to do with them after I have them. I was operating under the misconception that SG readings were mostly to determine ABV which I wasn't overly concerned about. My results were ok so it seemed like it wasn't broke so I didn't see the need to fix it. Starting fresh again, so incorporation of this into my processes seems like it could be worthwhile. I'll need to get a new hydrometer since my wife dropped mine when we were setting up my work area.
I don't know that you need to know what your ABV is, but you may want to know how much sugar is in fruit if you are simply juicing the fruit and not planning to add sugar. Is there enough sugar in the juice to allow the wine to age a few months or is it more likely that it will spoil? Also unless you know the starting gravity you really are driving in a fog without lights when it comes time to bottle. OK, so it's been a month but is there still sugar that will ferment? Has it stalled? With beer, you are using malted barley and that malted barley is always going to have the same amount of sugar (plus or minus). With wine the fruit is never as constant. AND you will likely use different fruit or the same fruit from different harvests. Malted barley meets all the nutritional needs of the yeast. Most fruit - apart from wine grapes - is deficient in nutrients so unless you are using the correct amount of the correct nutrition you cannot know whether the yeast will quit in mid ferment. Of course, if you are using kits and you wanna rely on the manufacturer and you know you have not over /under diluted the concentrate then if you don't want to use the hydrometer as your speedometer /odometer then more power to ya... Most folk , I think, prefer to drive with lights and gauges, though some pilots learn to fly blind, without instruments.
My hydrometer arrived earlier this week so I set off for the local home brew shop and picked up a WE LE20 Synergy kit since the wife prefers whites. Proceeded to clean up the old equipment. While sanitizing my fermenting bucket the spigot was dripping. Inspected it and found that the plastic had split. Back to the home brew store for a new spigot. Installed the spigot, sanitized everything again and started my wine. SG- 1.098. Sprinkled the yeast and snapped on the lid. Still a little chilly in the basement. Installed a brew belt to help with temperatures. I guess it’s working because the airlock was popping slowly this morning when I checked on it.
Save yourself a bit of work and just put a nice towel or cloth over the bucket. That will save the hassle of snapping the lid on and off and let the must 'breath.' Airlock only tell you that some sort of gas is coming out of the bucket. Your nose will tell you that a ferment is coming along nicely and in fact after a while you can tell how strong the ferment is by the amount of the fermentation scent. Hydrometer is the accurate measure but your nose will tell you a lot too. Espcially if an off smell develops./