Blanching vegetables preserves nutrients
Freezing vegetables, if done correctly can help you store good quality food for later use.
Freezing is one of the simplest methods of preserving foods. Michigan State University Extension recommends freezing foods at their peck of ripeness. Immature or over-ripe food should not be frozen. The fresher the food when frozen, the better the food will taste once thawed.
Enzymes in vegetables help them to grow and mature, and once the vegetables are harvested, these enzymes can cause changes in flavor, texture and color.
The term blanching refers to the process of immersing vegetables into boiling water or steam for a timed period and then rapidly cooling in ice water to prevent further cooking. Blanching inactivates vegetable enzymes, allowing blanched, frozen vegetables to have better quality over time. Blanching also cleans off dirt and organisms from the surface of vegetables. According to the National Center for Home Food Preservation, immersing vegetables in boiling water or steam for a brief period of time maintains their quality and nutrition.
Blanching times vary with the size and type of each vegetable. It is important to follow research-based recipes for exact blanching times because under blanching stimulates the activity of enzymes and is worse than not blanching while over blanching can cause loss of flavor, color, vitamins and minerals.
Water blanching requires one gallon of water per pound of prepared vegetables. During the blanching process, vegetables are put in a blanching basket or colander, lowered into rapidly boiling water, and covered. The blanching time begins when water returns to a rolling boil.
Steam blanching is recommended for some vegetables, but takes about 1.5 times longer than water blanching. Steaming requires a pot with a tight lid and a basket that holds the food at least three inches above the bottom of the pot. To steam blanch, put one or two inches of water in the pot and bring water to boil. Place vegetables in single layer so that the steam reaches all parts of the vegetables. Cover and count steaming time according to recipe.
When blanching is complete, quickly cool vegetables in a large quantity of cold water. Cooling vegetables should take the same amount of time as blanching. Drain vegetables thoroughly after cooling and select appropriate freezer containers to store the blanched vegetables in. Appropriate containers should be moisture resistant, durable, leak proof, protect from odors and easy to seal. Freeze foods as soon as they are sealed and keep freezer temperature at zero degrees or below.
Freezing is a safe method to preserve any food. Foods with a high water content, like lettuce may not have an acceptable quality. Taking this in consideration, any food can be frozen, but following proper blanching times and recipes will led to a higher quality product.