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Morris Plains, NJ, United States

Corti H.R.,University of Buenos Aires | Angell C.A.,Arizona State University | Auffret T.,Pfizer | Levine H.,Food Polymer Science Consultancy | And 4 more authors.
Pure and Applied Chemistry | Year: 2010

This paper describes the main thermodynamic concepts related to the construction of supplemented phase (or state) diagrams (SPDs) for aqueous solutions containing vitrifying agents used in the cryo-and dehydro-preservation of natural (foods, seeds, etc.) and synthetic (pharmaceuticals) products. It also reviews the empirical and theoretical equations employed to predict equilibrium transitions (ice freezing, solute solubility) and non-equilibrium transitions (glass transition and the extrapolated freezing curve). The comparison with experimental results is restricted to carbohydrate aqueous solutions, because these are the most widely used cryoprotectant agents. The paper identifies the best standard procedure to determine the glass transition curve over the entire water-content scale, and how to determine the temperature and concentration of the maximally freeze-concentrated solution. © 2010 IUPAC.

Kweon M.,Campbell Soup Company Pepperidge Farm | Slade L.,Food Polymer Science Consultancy | Levine H.,Food Polymer Science Consultancy | Gannon D.,Kraft Foods Inc.
Critical Reviews in Food Science and Nutrition | Year: 2014

The many differences between cookie- and cracker-baking are discussed and described in terms of the functionality, and functional requirements, of the major biscuit ingredients-flour and sugar. Both types of products are similar in their major ingredients, but different in their formulas and processes. One of the most important and consequential differences between traditional cracker and cookie formulas is sugar (i.e., sucrose) concentration: usually lower than 30% in a typical cracker formula and higher than 30% in a typical cookie formula. Gluten development is facilitated in lower-sugar cracker doughs during mixing and sheeting; this is a critical factor linked to baked-cracker quality. Therefore, soft wheat flours with greater gluten quality and strength are typically preferred for cracker production. In contrast, the concentrated aqueous sugar solutions existing in high-sugar cookie doughs generally act as an antiplasticizer, compared with water alone, so gluten development during dough mixing and starch gelatinization/pasting during baking are delayed or prevented in most cookie systems. Traditional cookies and crackers are low-moisture baked goods, which are desirably made from flours with low water absorption [low water-holding capacity (WHC)], and low levels of damaged starch and water-soluble pentosans (i.e., water-accessible arabinoxylans). Rheological (e.g., alveography) and baking tests are often used to evaluate flour quality for baked-goods applications, but the solvent retention capacity (SRC) method (AACC 56-11) is a better diagnostic tool for predicting the functional contribution of each individual flour functional component, as well as the overall functionality of flours for cookie- and/or cracker-baking. © 2014 Copyright Taylor and Francis Group, LLC.

Van Steertegem B.,Catholic University of Leuven | Pareyt B.,Catholic University of Leuven | Slade L.,Food Polymer Science Consultancy | Levine H.,Food Polymer Science Consultancy | And 2 more authors.
Cereal Chemistry | Year: 2013

The impact of heat treating wheat flour (for 2 or 5 h at 80 or 100°C) on its functional properties was studied with solvent retention capacity (SRC) tests and related to changes in individual groups of flour constituents. Heat treatments increased the overall water retention capacity (from 55.6% for control flour to 62.4% for flour heated 5 h at 100°C) as well as sucrose SRC (from 85.0 to 113.5%), although no changes were observed in sodium carbonate SRC. The decrease in lactic acid SRC values (from 113.1 to 97.4%) indicated that heat treatment restricted swelling of the protein network. As deduced from a decrease in both the level of proteins extractable in sodium dodecyl sulfate-containing medium and the level of free sulfhydryl groups, the restricted swelling was related to protein cross-linking within the flour particles. Such upfront polymerization prevented proper hydration and gluten network formation during mixing. Starch (swelling) properties were also affected by heat treatment. Finally, the impact of heat treatment on flour SRC profiles was comparable to that noted when chlorinating wheat flour. © 2013 AACC International, Inc.

Roos Y.H.,University College Cork | Karel M.,Massachusetts Institute of Technology | Labuza T.P.,University of Minnesota | Levine H.,Food Polymer Science Consultancy | And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2013

Crystalline structures of sugars, particularly that of sucrose, depend on crystallization conditions and the presence of impurities. Sugar crystals show melting that often occurs at low temperatures with time-and temperature- dependent characteristics. Melting at low temperatures can be accounted for by the presence of impurties and defects. Sugar crystals also contain noncrystalline regions that may undergo decomposition and subsequent dissolution at the decomposition interface and acceleration of decomposition reactions. Such processes with melting establish a supersaturated condition for the remaining crystals, leading to a time-dependent melting point depression and subsequent melting of the remaining crystals. Decomposition of sugars, as well as dissolution and melting of sugar crystals, are separate phenomena, although they are commonly found to coincide. Decomposition of sugars requires the presence and mobility of molecules for reactions outside the crystal lattice; that is, the molecular mobility of amorphous or melted regions is a prerequisite for decomposition, whereas melting of sugar crystals occurs as a separate thermodynamic process with no chemical change of the molecules. © 2013 American Chemical Society.

Kweon M.,U.S. Department of Agriculture | Kweon M.,Campbell Soup Co. | Slade L.,Food Polymer Science Consultancy | Levine H.,Food Polymer Science Consultancy
Cereal Chemistry | Year: 2011

Solvent retention capacity (SRC) technology, its history, principles, and applications are reviewed. Originally, SRC testing was created and developed for evaluating soft wheat flour functionality, but it has also been shown to be applicable to evaluating flour functionality for hard wheat products. SRC is a solvation test for flours that is based on the exaggerated swelling behavior of component polymer networks in selected individual diagnostic solvents. SRC provides a measure of solvent compatibility for the three functional polymeric components of flour- gluten, damaged starch, and pentosans-which in turn enables prediction of the functional contribution of each of these flour components to overall flour functionality and resulting finished-product quality. The pattern of flour SRC values for the four diagnostic SRC solvents (water, dilute aqueous lactic acid, dilute aqueous sodium carbonate, and concentrated aqueous sucrose solutions), rather than any single individual SRC value, has been shown to be critical to various successful end-use applications. Moreover, a new predictive SRC parameter, the gluten performance index (GPI), defined as GPI = lactic acid/(sodium carbonate + sucrose) SRC values, has been found to be an even better predictor of the overall performance of flour glutenin in the environment of other modulating networks of flour polymers. SRC technology is a unique diagnostic tool for predicting flour functionality, and its applications in soft wheat breeding, milling, and baking are increasing markedly as a consequence of many successful, recently published demonstrations of its extraordinary power and scope. © 2011 AACC International, Inc.

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