1.4 Maple Syrup Density Measurement. 1.4.1 Background; 1.4.2 Hydrometers; 1.4.3 Hydrotherms; 1.4.4 Refractometers . 1.4.4.1 Optical Refractometers; 1.4.4.2 Digital Refractometers; 1.4.5 Temperature Correction; 1.4.6 Instrument Calibration . 1.4.6.1 Hydrometers; 1.4.6.2 Thermometers; 1.4.6.3 Refractometers; 1.4.7 Collecting a Representative Sample
Because of this distinction, you may safely use fish even after the sell by date has lapsed. If there is a use-buy date on fresh fish, then it is recommended to either cook or freeze the fish by that date. Commercially frozen fish, if kept frozen, can be safely stored for 10-12 months.
Yogurt can be safely eaten up to 10 days after its sell-by date; beyond then the live bacterial cultures (which are healthful ingredients, and act as preservatives) will start to die. Mayonnaise is still good for a month after its expiration date (unopened) and up to four months after opening. Eggs, properly refrigerated, should last at least three to five weeks after the sell-by date. Canned goods are good to eat long after labeling dates, as long as the can is in good shape.