Just put a stainless steel piece of silverware into the container. It will help to keep the salad mixes from turning brown and will keep them fresher longer.

The avocados you want to use are still hard. To speed up the ripening process, bury the avocado in a container of uncooked rice. The dense grains will concentrate the naturally occurring ethylene gas in avocados that promotes ripening, cutting the wait in half. This method also works for mangoes, persimmons, bananas, papaya and other slow ripening fruits.

Green Tea: 6 months, cancer fighting antioxidants called catechins are one of the most beneficial compounds found in green tea. But a Department of Agriculture study in 2009 found that green tea’s catechins lose 32% of their potency after just six months. To get the most antioxidant power from your cup, use fresh, loose leaves, and store them in an airtight tin to block out moisture and light.

Olive oil: The Journal of Food Science study found that the rich polyphenol antioxidants in olive oil, which have been shown to help ward off cancer and heart disease among other things, can deteriorate after six months.

Nuts and nut oils: 3 to 6 months, walnuts and pecans are top sources of healthful fats that turn rancid rapidly. In a study publish in the International Journal of Food Sciences and Nutrition in 2009 the British researchers discovered that one brand of walnut oil had an actual shelf life 20 times shorter than the “best before” dated printed on the label.

When sautéing onions, mushrooms and other vegetables, use a small amount of low-sodium both or water instead of butter or oil