Effect of Iron Fortification on Quality of Cheddar Cheese. 2. Effects of Aging and Fluorescent Light on Pilot Scale Cheeses

Abstract

Based on previously successful iron fortification of 1-kg batches of Cheddar cheese, we studied the effect of fortification on cheese aging and shelf-life. Five 12-kg batches of Cheddar were made: an unfortified control cheese and cheese fortified with Fe-casein, Fe-polyphosphate-whey protein, Fe-whey protein, or FeCl3. The respective iron levels and recoveries of fortified cheeses were 40, 39, 39, and 42 mg/kg cheese, and 69, 68, 65, and 70%. All cheeses had similar low thiobarbituric acid numbers up to 12 mo of aging. Trained panelists detected less oxidized off-flavor in the control and Fe-whey protein cheeses at 15 d but did not detect any differences among the cheeses thereafter. They judged superior the cheese flavor for Fe-polyphosphate-whey protein, FeCl3, and Fe-whey protein cheeses at 1 mo and for Fe-casein cheese at 9 mo, but did not detect differences among the cheeses at 15 d or 4, 7, or 12 mo. A panel of 66 lay people did not detect differences in texture among the cheeses, but judged Fe-casein and control cheeses to have better cheese flavor. Fluorescent lighting slightly increased thiobarbituric acid numbers the same degree in all cheeses. Overall, quality of iron-fortified cheese was as good as unfortified cheese.