How sterile is too sterile?

I use sodium metabisulphite to "sanitize" my equipment before use - I run it through the siphon hose. swirl it in the carboy, pour it over things, etc. I wash my hands reasonably well and I rinse with mouthwash before siphoning. This seems to have worked well with me - no total failures (with kit wines, anyway - more in this in a minute). Of course I just may not know any better, or maybe I've been lucky so far.

HOWEVER - I have not had very good luck with the few attempts I've made at making wine "from scratch" - specifically a couple batches of apple wine, 2 attempts at raspberrry wine and 1 carrot wine. In each case there have been "off" smells and one of the apples and the carrots had such a chemical taste to them I just poured 'em out. I am wondering if the problem I am having with those is that the must in the kit is sterile to start with (I think?) and so there's more room for error than there is with a non-kit wine.

I use bleach on my gallon jugs, soap and hot water on everything else, and a final rinse in a campden tablet (sodium metabisulphite) solution before use. About half of the wine I make is fruit wines from scratch - if you follow the recipes on Jack Keller's wine site, you shouldn't go wrong. I have found though that fruit and vegetable wines don't necessarily taste real well in the beginning- they benefit from bulk aging as well as bottle aging. For example, my pumpkin wine initially tasted like rocket fuel, but by the time I bottled at about 7 months, I was very happy with it. But I'm supposed to let it age to about 2 years old (so I'll wait) - carrot wine I've heard is the same way. Darlene

Harry, I wash every piece of winemaking equipment (including my hands) in clean water just before using it. Then I wash everything (except my hands) in clean water before I put the equipment away. Good luck, lum

Lum posted one reply already but here is another of his which I think is a classic.

Don

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I "sterilized"everything when making wine at home twenty years ago. Now, at the winery, I seldom attempt to sterilize anything. Here is my perspective on wine "bugs."

Professional winemakers always wash their receivers, crushers, etc. before grapes are processed. The pros make sure everything is clean, but they seldom attempt to "sterilize" their equipment. On the other hand, the home winemaking literature is filled with statements such as "...assemble all the winemaking equipment and sterilize everything with a sulfite solution." Have you ever wondered why the pros seem so indifferent about "sterilizing" their equipment?

On average, a ton of California wine grapes contains seven pounds of dirt, one mouse nest, 247 bees, 198 wasps, 1,014 earwigs, 1,833 ants, 10,899 leaf hoppers and four pounds of bird droppings, more or less. Besides the above materials, the waxy coating on grapes contains a variety of microorganisms. Freshly crushed, grapes contain several non grape substances and many microorganisms, so attempting to "sterilize" crush equipment seems a bit futile.

Grape juice is a hostile environment to most microbes because it has a low pH, high sugar level and high phenolic content. Alcohol is present after fermentation, so wine is a less hospitable environment than juice. No human pathogens can multiply in wine. Even most of the native yeasts on the grape skins expire as the alcohol accumulates during fermentation. In fact, only a few very special microorganisms can survive in wine, and because of their special requirements, most of these microbes cannot survive outside a wine environment. Unfortunately, vinegar bacteria seem able to survive almost everywhere, so they are a notable exception.

The yeasts found in wine are primarily Saccharomyces (sugar loving). Popular wine yeasts such as Montrachet, Epernay II and Pasteur Red are Saccharomyces cerevisiae. The more alcohol tolerant yeasts such as Prise de Mousse and Pasteur Champagne are strains of Saccharomyces bayanus. Only a few other yeasts such as Schizosaccharomyces, Brettanomyces, Mycoderma and the Flor yeasts grow in wine. These yeasts are usually considered wine spoilage organisms.

Wine bacteria are mostly limited to two major groups. Lactic acid bacteria, belonging to the Lactobacillus, Leuconostoc and Pediococcus genera, convert malic acid into lactic acid. Some lactic bacteria can also convert sugar directly into acetic acid. Fortunately for winemakers, lactic bacteria are sensitive to sulfur dioxide, so they are easy to control.

The second group of wine bacteria is the vinegar bacteria, (Acetobacter). These microbes convert ethyl alcohol into vinegar. They are a major source of wine spoilage, and they are not very sensitive to sulfur dioxide. However, vinegar bacteria require oxygen to convert alcohol into vinegar. This is why wine storage containers are always kept full, or the oxygen content of the gas in the head space must be limited to 0.5% or less.

None of the molds grow directly in wine. Although, molds can grow in dilute wine solutions, so hoses, tanks, etc. must be washed and drained carefully to avoid mold contamination.

Now, I think "clean" not "sterile."

Regards, lum

I use sodium metabisulphite. Sometimes I will let a carboy soak in a water/bleach solution for a few days, then rinse it out several times with water.

I think some of the sterilization is overdone on kits. Eg they usually say something like rack the wine from carboy to say a fermenter, add your sulphite/fining agent etc, stir then rack back to sanitized carboy.

Think about it--if you use the same carboy that you just stored the wine in for 4 weeks and will rerack back to it, why sterilize it obsessively. Rinse it with water, maybe a little sulphite-that's it.

When the wine is fermenting, it is not sterlile at all. I certainly don't soak everything for 20 minutes.

As for bottling, I have once of those table squirters (?) and use sulphite solution again into the bottle and let it dry on a bottle tree for a few minutes. That's it. So far, no problems