The internet source for discussion and knowledge on pasteurization equipment, technology, and equipment selection for flash pasteurization, tunnel pasteurization, and used pasteurizers.

Pasteurized Wine at Home

Monday, November 29, 2010

It has become extraordinarily difficult to find pasteurized wine. The high alcohol content combined with excellent filtering processes, sterility in the winery, and the general acceptance that wine must be sheltered from heat and sunlight and stored under certain conditions have allowed the wine industry to avoid pasteurization. As it is a thermal process wine is more susceptible to changes in flavor due the temperature than other beverages. Its common knowledge that the wine industry is highly competitive when it comes to flavor.

Pasteurization is a process of time and temperature originally created for use with wine. Pasteurization in this article is outlined based on two levels which are considered "high PU" and "low PU" depending on the purpose of the pasteurization. Low PU is intended to stop fermentation and neutralize any bacteria which may have been picked up in the wine making process. High PU is for use if the wine is needed for medical purposes (i.e. consumption by persons with weakened immune systems, cautionary pregnancy, etc).

Contrary to popular belief, Kosher wine is not pasteurized. It is made from pasteurized grape juice but fermented and subject to contamination after the fact.

The process outlined here is for a 750ml bottle of red or white wine. The pasteurization time varies depending on the water temperature being used. This process can be executed in a sink or any bath of water. The water temperature can be determined by running hot water over the end of a thermometer for 2 - 3 minutes. As can be seen by the pictures part of the process is to keep water flowing at all times. New water needs to be injected into the bottom of the bath allowing the water to overflow out the top. Other techniques (such as cracking the drain) work although sometimes difficult to ensure that the loss of water through the drain is the same as the water being put into the process. This leads to issues with level.

The immersion time for the product depends on several factors:
  • The water temperature being used for the pasteurization process
  • The starting temperature of the wine (in this case room temp or refrigerated)
  • The size of the bottle (in this case the bottles are 750ml red or white table wine)
  • The determination of pasteurization to high or low PU levels
The chart below outlines the required time for immersion to achieve the pasteurization goal.  Remember that sudden changes in temperature can cause glass to crack. Remember to be gentle with temperature changes upward or downward to give the glass time to adjust. When the pasteurization process is complete, use the cold water to bring the bath temperature down. Cooling the bottle as quickly as possible will minimize flavor impact. To judge the impact to the flavor, consider using two bottles of the same product, pasteurizing one bottle and leaving the other as a control group.

Click on the chart to blow up to full size. Also note that you will not need a thermometer in the wine bottle as shown in these pictures. Corks have been known to lift in this process and a screw cap may be advantageous.

Egg Recall, Pasteurization, and Raw Milk

Monday, November 1, 2010

Are eggs pasteurized? Short answer is no if you are cracking the egg on the skillet. Shell eggs come straight from the hen. In liquid form "Egg Beaters" and other forms of liquid eggs can be put through the same pasteurization process as milk.  

There are important lessons from eggs that can be learned regarding raw milk. The recent egg recall is an example of what could happen with the public supply of milk. Eggs (like raw milk) are collected from multitudes of farms and shipped to and packaged at co-ops. From there they are spread through central distribution networks. While higher in nutritional value raw milk is at risk of carrying food borne illness. The thermal treatment of pasteurization followed by refrigeration greatly reduces this risk removes and makes it safe for distribution over wider areas even if there was contamination. No one has ever made the statement that all raw milk carries food borne illness - nor do eggs. Pasteurization simply reduces this risk down to the level that it would be neutralized and digestible if harmful bacteria were to habitate in either.

Raw eggs are "unprotected" until recently. Look for the eggs with a P in circle. This denotes one of the few pasteurized eggs on the market. Locate a store with pasteurized eggs by clicking this link. Unpasteurized eggs do not pose a threat if they are seriously cooked. Pasteurized eggs are particularly recommended for infants, senior citizens, and pregnant women - the three classifications that run the most risk from the impacts of salmonella. The USDA fact sheet on salmonella can be located here. If like your eggs runny (particularly if your pregnant) and / or put raw eggs into other formats (like Caesar dressing) consider pasteurized eggs.