| Title: | Lactose and galactose content in cheese results in overestimation of moisture by vacuum oven and microwave methods |
| Author(s): | Lee H; Rankin SA; Fonseca LM; Milani FX; |
| Address: | "Department of Food Science, University of Wisconsin, Madison 53706. Department of Food Science, University of Wisconsin, Madison 53706. Electronic address: sarankin@wisc.edu. Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) and School of Veterinary Medicine, Universidade Federal de Minas Gerais, Belo Horizonte-MG 31270-901, Brazil" |
| ISSN/ISBN: | 1525-3198 (Electronic) 0022-0302 (Linking) |
| Abstract: | "Moisture determination in cheese is a critical test for regulatory compliance, functionality, and economic reasons. Common methods for moisture determination in cheese rely upon the thermal volatilization of water from cheese and calculation of moisture content based on the resulting loss of mass. Residual sugars, such as lactose and galactose, are commonly present in cheeses at levels ranging from trace amounts to 5%. These sugars are capable of reacting with other compounds in cheese, especially under the thermal conditions required for moisture determination, to yield volatile reaction products. The hypothesis of this work is that residual sugars in cheese will be converted into volatile compounds over the course of moisture determination at a level sufficient to result in overestimated cheese moisture. A full-factorial statistical design was used to evaluate the effects of cheese type, sugar type, sugar level, method type, and all interactions. Cheddar and low-moisture, part-skim (LMPS) Mozzarella cheeses were prepared with 1, 3, and 5% added lactose or galactose, and subjected to either vacuum oven or microwave-based moisture determination methods. Browning index and colorimetry were measured to characterize the color and extent of browning. Volatile analyses were performed to provide chemical evidence of the reactions proposed. The presence of residual sugars altered moisture calculations as a function of cheese type, sugar type, sugar level, method type, and numerous interactions. At higher concentrations of residual sugar, the percentage moisture determinations were increased by values of up to 1.8. Measures of browning reactions, including browning index, colorimetry, and volatile profiles demonstrate that the proposed browning reactions played a causative role. This work establishes the need to consider cheese type, sugar type, sugar levels, and method type as a means of more accurately determining moisture levels" |
| Keywords: | Cheese/*analysis Colorimetry Food Analysis/*standards Galactose/*analysis Lactose/*analysis Maillard Reaction Microwaves Vacuum Volatile Organic Compounds/*analysis Water/analysis cheese lactose moisture; |
| Notes: | "MedlineLee, H Rankin, S A Fonseca, L M Milani, F X eng Research Support, Non-U.S. Gov't 2014/03/19 J Dairy Sci. 2014 May; 97(5):2567-77. doi: 10.3168/jds.2013-7522. Epub 2014 Mar 13" |
