1964 JOURNAL OF FOOD SCIENCE—Vol. 67, Nr. 5, 2002 © 2002 Institute of Food Technologists Sensory and Nutritive Qualities of Food JFS: Sensory and Nutritive Qualities of Food Using Edible Coating to Enhance Nutritional and Sensory Qualities of Baby Carrots Y. MEI, Y. ZHAO, J. YANG, AND H.C. FURR ABSTRACT: Xanthan gum coating was used to carry 5% Gluconal Cal, a mixture of calcium lactate and glucon- ate, and 0.2% –tocopheral acetate (vitamin E) by weight, respectively. Peeled baby carrots were dipped in the coating solutions, dried, and then stored at 2 °C and 85% relative humidity for up to 3 wk. Calcium and vitamin E contents of the coated samples, per serving (85g), increased from 2.6% to 6.6%, and from 0 to about 67% of the Dietary Reference Intakes (DRI) values respectively. Edible coatings (p<0.05) improved the desirable surface color of carrots without effects (p<0.05) on the taste, texture, and fresh aroma and flavor except for a slightly slippery surface. The – carotene level in the baby carrots (p<0.05) was not affected by edible coating. Keywords: calcium, –tocopheral, baby carrots Introduction W HITE DISCOLORATION ON THE SURFACE OF PEELED BABY CARROTS is the result of reversible surface dehydration and irrevers- ible formation of lignin, which reversibly affect their storage quality and shelf life (Bolin and Huxsoll 1991; Howard and Grif- fin 1993; Cisneros-Zevallos and others 1995). Edible coatings have been applied to the surface of fresh carrots to control white surface discoloration by acting as moisture barrier or surface moisturizer (Avena-Bustillos and others 1993a,b; Howard and Dewi 1995, 1996; Cisneros-Zevallos and others 1997; Li and Barth 1998). An edible coating can also be used as an effective carrier of many functional ingredients, including antimicrobial agents, antioxidants, flavorings, and colorants (Chen, 1995). Integration of these minor ingredients can enhance food stability, quality, functionality, and safety. While an edible coating served as carri- er of nutritional ingredients, it will provide an excellent vehicle to enhance the nutritional value of foods by adding nutrients that are present in low quantity. There has been increased consumer interest in the health- enhancing role of specific foods or physiologically-active food components, so–called nutraceuticals or functional foods (Hasler 1998). Nutraceuticals are natural, bioactive chemical compounds that have health promoting, disease preventing, or medicinal properties. Calcium and vitamins have been identified as impor- tant nutraceuticals and play a significant role in the human body to prevent certain diseases (Pszczola 1998; Elliott 1999). Calcium is a common intracellular messenger, a cofactor for extracellular enzymes and proteins, and also is essential for the development of bone and teeth (Weaver and Heaney 1998). Deficiencies in calcium result in bone and tooth diseases, and increased risk of hypertension, preeclampsia, and colon cancer. The Dietary Ref- erence Intakes (DRI) for calcium are 1300 mg/d for individuals aged 9-18 years, 1000 mg/d for adults aged 19 to 50 years old, and 1200 mg/d for individuals over the age of 51 years (FNB 1999). Vitamin E functions in vivo as a chain-breaking antioxidant that prevents propagation of free radical damage in biologic membranes, and is believed to protect the human body against certain types of cancers, cardiovascular disease, cata- racts, arthritis, diabetes, and Alzheimer’s disease (Elliott 1999). The most recent Dietary Reference Intake (DRI) for vi- tamin E is 15 mg/d (220 IU/d) for both men and women (FNB 2000). High intakes and high serum vitamin E levels have been associated with reduced risk for coronary heart dis- ease in men and women, reduced risk of prostate cancer, and may slow progression of Alzheimer’s disease (Meydani and Hayes 1999). Vitamin E is relatively safe compared to other fat-soluble vitamins. Peeled baby carrots are high in nutrients, such as vitamin A and carotene, vitamin C, and dietary fiber, but a poor source of calcium and vitamin E. According to USDA Nutrient Database for Standard Reference Release 14 (2001) (http:// www.nal.usda.gov/fnic/foodcomp/Data/SR14/sr14.html), 100 g of edible baby carrots contains about 23 mg of calcium and a negligible amount of vitamin E. A serving of carrots only affords about 2% DRI for calcium and 0% DRI for vitamin E, respectively. The use of edible coatings as carriers of calcium and vitamin E on fresh baby carrots is a natural extension of their barrier property, and would further enhance and expand the functionality of edi- ble coatings by providing additional health benefits to consum- ers. The objectives of this study were to develop the formulation of edible coatings for incorporating calcium and vitamin E, and to demonstrate the feasibility of applying these coatings on peeled baby carrots. Materials and Methods Materials The materials used for coating were xanthan gum (Supra, Rhodigel, Rhodia, Cranbury, N.J., PA., U.S.A.), –tocopheral acetate (Sigma, St. Louis, Mo., U.S.A.), acetylated monoglycer- ide (Danisco, New Century, Kans., U.S.A.) and Gluconal Cal (Glucona America Inc., Janesville, Wis., U.S.A.). Xanthan gum is an anionic polymer with cellulosic backbone substituted on alternate glucose residues with a trisaccharide side chain. Glu- conal Cal is a mixture of calcium lactate and calcium glucon- ate, and has water solubility up to 40 g /100 mL with neutral taste. –tocopheral acetate is a very stable form of vitamin E,