2017 Grape Harvest Preparation 

Friday, June 16, 2017 - 2:30pm

Matt Clark, PhD., Project Director & Drew Horton, Enology Specialist

Here are a few practical and easy-to-do things to get your wine production operations prepared and ready for a safe, happy, and healthy wine harvest.

Order early

Order your winemaking ingredients early. Some providers will give you a discount of some kind, or free shipping, if you order early. Another reason to order early is that some items are more popular, or certain sizes are limited, and if you wait until the last moment they may be out or back-ordered. Thinking about your order will also force you to really consider the amount and types of winemaking you expect to do in a given season, and to organize those thoughts in the amount and type of things you use: yeasts, nutrients, enzymes, stabilizers/clarifiers, pressing aids, tannins, etc. Most ingredients have expiration dates, properly sealed and stored leftovers can be used again the next year or two. Double check what you are using and for what purpose. Some ingredients may sound the same but have different purposes, such as yeast hydration nutrient and fermentation nutrient.

All of the above comments apply to your barrels as well. Not every barrel is in stock or on-the-shelf here in the USA and shipping barrels cheaply takes time. Again, it makes you think ahead about how many and what type of barrels you should be considering for the type of wines and batch sizes you will be making. And don’t forget to order enough barrel racks, an extra rack or two can be handy for splitting up odd number barrel lot sizes in your cellar.

Get to know your grapes

Get your grape purchase contracts and agreements settled and signed off now, or make those hand-shake deals when you know you can. Don’t wait until the last minute to start thinking about where you will get fruit. By this time of year, after fruit set, growers should have a pretty fair idea of what and how much of each varietal they will have available. The best practice is to make all these arrangements in person. Spend the time to walk the vineyards you are interested in. It forces you to actually look at the vineyard and the vines, to taste and smell after veraison, and to get to know better your primary ingredient and the people who grow it. Check with previous wineries the grower may have sold to in previous years. Don’t (always) rely on a grower to provide you with good quality harvest chemistry data, go out yourself, pick your own samples, and make your own measurements. It is good practice, strengthens the relationship with the grower, and will prepare you for all the lab work coming soon.

Get your lab working

Speaking about lab work and testing of juice and wine, you really do not have a more important winemaking tool than a modern, quality and reliable pH meter. The acids in juice and wine are important, and pH is without question the one winemaking parameter you can’t know enough about. A pH meter and probe require special care, and not just during harvest, you should be using it the year around, and keeping the probe maintained and cleaned. Having a spare probe on your shelf is worth consideration. Throw out your old calibration buffer solutions and buy new ones, every six months is recommended. It is also a good idea to check your pH meter’s accuracy by comparing it with another’s, either a lab or another winery or brewery’s. It is not unheard of to have two meters in one winery.

Preventative maintenance

Check and maintain your processing equipment, and order certain normal-wear parts ahead of time; O-rings, gaskets, seals, etc. Depending on the make, style, and supplier of your press, you should either have a spare bladder or membrane, and a repair kit, in-house, or confirm that your press supplier can get you a new one within 24-hour shipping. If any of your equipment comes directly from Europe, keep in mind the whole place is on vacation in August! This advice also applies to your pumps, keep a spare impeller or diaphragms (and/or other parts) in-house, and take your pumps apart to clean and lubricate now while you have the time.

Make sure you have the right tools to maintain your equipment, and use them now to tighten or replace loose or missing screws, bolts, seals, flanges, belts, etc. Make sure you have grease, and grease gun(s); food-grade for your press, de-stemmer/crusher and pumps, and normal shop grease for other mechanical non-food contact equipment. Remember to make it a daily or weekly routine to use those grease guns especially on press and de-stemmer/crusher bearings. If you have a fork-lift or other device, an annual service in late July or early August is also good practice. Hydraulic systems and seals should be operated and checked, and you should have some extra hydraulic fluid in-house. Find out where the closest mechanic or auto shop that can repair a blown hydraulic hose is, you will be glad you know this in advance. And if your equipment requires metric tools, have them on hand before you need them.

Get your air-cooling and temperature control systems inspected and maintained. Make sure you form a good, positive and long-lasting relationship with your local HVAC technician, a person who can be a critical player in the success of your winemaking (as these systems only fail on Sunday afternoons and holidays). Check, clean and/or replace air filters as needed in all your ventilation, heating, cooling, and chilling systems.

If you are using “floating lid” variable capacity tanks, consider buying new lid-gaskets each or every other year. These types of lids have been found to be an entry for oxygen, bacteria and spoilage organisms unless they are rigorously maintained, cleaned and sanitized. During fermentation, don’t use them, use plastic sheeting and a string and bungee cord combo, the fermenting wine will be protecting itself from oxidation by its own production of CO2 gas. When you are using these lids, keep in mind the air-pump, hoses, hose-clamps and fittings can fail, and the pressure-gauge needle can get “stuck” and give erroneous readings. It is best practice when using floating-lid tanks to manually and visually check the lid-seal (not just the gauge) every day, do less at your own peril. When storing the lids, take all of the pieces apart and the gasket off the lid, and clean and sanitize them before putting them away.

Safety training

Make sure your crew has important foundational and on-going safety training of some kind, and that this training is documented. Do not allow untrained personnel to operate or clean hazardous equipment without proper personal protective equipment and safety training, including “lock-out/tag-out” procedures. A lot of winery equipment is very capable of doing grave damage to body parts. With names like “crusher” and “press” you don’t have to look far to identify safety issues. Make sure anyone using pallet-jacks knows proper and safe operation, and anyone using a forklift had better be certified, every three years, your insurance company probably requires it as does MNOSHA. Wearing open-toed shoes or sandals should not be allowed while working in a winery.

CO2 gas produced by active fermentation can kill a worker in a few seconds, make sure all winery staff (including hospitality staff) knows about the practical considerations of CO2 gas causes and effects, and how to properly ventilate an actively fermenting cellar. Every year somewhere in the world workers are asphyxiated by CO2 gas in wineries. Many winery tanks can be considered confined spaces, and you should be aware of proper and safe confined space operations. Confined space training, documentation, and permitting may be required depending on various considerations, be aware of what this is all about, and consider starting your own simple and effective confined space procedures and protocols as needed. For further information about Confined Space considerations see this MNOSHA Hazard Safety Alert, or contact MNOSHA at 877-470-6742: https://mn.gov/admin/assets/hazalert_confinedspace_tcm36-207158.pdf