Mozzarella cheese production has been gaining market share due in part to increasing market for pizza and ready to eat food items. Anti-caking agents are utilized in the production of shredded cheese for reducing clumping and increasing the appearance of separate cheese shreds. Six anti-caking agents were applied to low moisture part skim Mozzarella cheese and examined for effects on three major functional properties of Mozzarella cheese; meltability, stretchability, and free oil formation. Meltability determination utilizing a fabricated UW Meltmeter resulted in no significant differences between untreated samples (control) and samples treated with anti-caking agents containing cellulose, potato starch or mixtures including dextrose. Stretchability measurements taken using a modified helical viscometry procedure also resulted in no significant differences between control and treated samples. Significant differences were found when comparing free oil percentages obtained from varying treatments of anti-caking agents. A mixture of potato starch and cellulose resulted in the lowest level of free oil among all samples tested. Because potato starch treated samples performed equally to cellulose treated samples in both meltability and stretchability testing, anti-caking agents containing potato starch could be considered as an alternative to cellulose-based anti-caking agents. In addition, the use of potato starch alone and in conjunction with powdered cellulose has been shown to be more effective for free oil control. By treating with potato starch, functional properties of shredded Mozzarella cheese have been positively altered in a way which may increase acceptability by consumers. / Master of Science

The effects of starch-based anti-caking agents on the browning of Mozzarella cheese were evaluated in this experiment. Six commercially available anti-caking agent treatments were examined and color measurements indicated that the starch-based anti-caking agents produced a baked cheese with a greater degree of browning than the samples treated with cellulose based anti-caking agents or no treatment (control). The cellulose-based treatments and the control also had a significantly greater moisture loss than the potato starch-based treatments. A negative correlation between percent moisture loss and the amount of browning was found (R2=0.51). The average surface temperature was at least 16 °C higher for the treatments containing potato starch than for the cellulose-based treatments. A significant relationship between average surface temperature and browning was also found (R2=0.67). These relationships suggest that the starch-based treatments impeded moisture loss, which decreased the amount of evaporative cooling. An increase in surface temperature resulted from the decrease in the amount of evaporative cooling and thus the Maillard reaction was accelerated leading to increased browning. The effects of the starch source were examined using starches from corn, rice and wheat. These starches were compared to commercially available potato starch and cellulose anti-caking agents. All starch sources were found to produce a greater degree of browning on the cheese sample compared to the cellulose treatment and control. Four adjuncts treatments, including dimethypolysiloxane, lactic acid, partially hydrogenated sunflower oil, and a combination of the dimethylpolysiloxane and sunflower oil were added to cheese treated with potato starch to determine if a reduction in the degree of browning could be achieved. No differences in browning between the potato starch treatment and those with added adjuncts were found. / Master of Science

Le mottage ou l’agglomération non désirée des cristaux déliquescents est un phénomène récurrent dans l’industrie, notamment au cours du transport et du stockage. Les variations des conditions environnantes sont fréquemment responsables de la dégradation de ce type de poudres. En particulier, les fluctuations de l’humidité ambiante conduisent à la formation d’une solution saturée par déliquescence du solide puis à la formation de ponts solides par évaporation de l’eau. Dans cette étude, on se concentre sur le chlorure de sodium. L’équilibre avec la vapeur d’eau et les cinétiques de prise et perte en eau sont analysés et reliés au comportement mécanique macroscopique des cristaux. Le contact avec des cristaux de différente nature tels que le sucrose met en évidence le phénomène de déliquescence mutuelle. Le modèle des solutions régulières appliqué aux systèmes ternaires comportant du NaCl, du sucrose et de l’eau permet de mieux comprendre la chute de déliquescence. La présence des molécules d’eau à la surface des cristaux et la condensation capillaire à faible humidité relative provoque la déliquescence de NaCl et du sucrose simultanément. L’évaporation de l’eau et la recristallisation des cristaux à partir de la solution ainsi formée sont inhibées, en particulier à la composition solide du point eutonique. Le comportement singulier à cette composition qui s’apparente à celui d’un corps pur montre une recristallisation partielle du mélange "eutonique" associée à la formation d’une phase amorphe dans les conditions de l’expérimentation. Afin d’éviter le renforcement au mottage, l’étude de différents agents anti-mottants révèle l’efficacité du stéarate de magnésium. / Caking or undesired agglomeration of deliquescent crystals is a recurrent phenomenon in industry, especially during transportation and storage. The variation of environmental conditions is often pointed out as a cause of the degradation of this kind of powders. More precisely, the fluctuations of ambient humidity lead to the formation of a saturated solution by deliquescence followed by the formation of solid bridges when water evaporates. Sodium chloride is chosen as a model substance in this study. The equilibrium with water vapor and the kinetics of water uptake and loss are analyzed and related to the mechanical macroscopic behavior of crystals. The contact with crystals of different nature such as sucrose highlights the phenomenon of mutual deliquescence. The model of regular solutions applied to ternary systems containing NaCl, sucrose and water allows a better understanding of deliquescence lowering. The presence of water molecules and capillary condensation at low relative humidity lead to the deliquescence of NaCl and sucrose simultaneously. Water evaporation and recrystallization of solid from such solution is compromised, especially at the solid composition of the “eutonic point”. The singular behavior at this composition which resembles to the one of a pure substance shows a partial recrystallization of the “eutonic” mixture and the formation of an amorphous phase under the experimental conditions applied. In order to avoid caking reinforcement, the study of differentanti-caking agents reveals the efficiency of magnesium stearate.