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The effects of polyphosphate on parameters of quality in shrimp (after thawing and cooking) were investigated using physicochemical analytical methods and low- field nuclear magnetic resonance ( LF 1 H NMR) spectroscopy. The NMR data were treated by bi-exponential fitting and compared with the physicochemical data. The physicochemical parameters demonstrated that treatments with different concentrations of sodium tripolyphosphate and different time exposures influenced parameters such as cook loss, moisture, pH, color and texture. These differences were reflected in the transverse relaxation ( T2) data. Bi-exponential fitting of the T2 resulted in the observation of two water populations in all samples, T21 and T22, with relaxation times in the ranges of 24-47 and 63-120 ms, respectively. Pronounced changes in the T21 and T22 relaxation data were observed during the different treatments, with polyphosphate revealing changes in water properties. Good linear correlations were observed between the T2 parameters and physicochemical data. Practical Applications Shrimp processing contains various steps, such as freezing and cooking, which can lead to the denaturation or aggregation of proteins. In this context, the use of polyphosphates prior to the freezing of shrimp can improve yields, water-holding capacity and the sensory attributes of the final product. The fish industry seeks to use polyphosphates in order to optimize production and obtain better quality products. Therefore, studies to identify the ideal phosphate concentration and contact time required for quality production in the frozen shrimp industry are important. Traditional analytical methods for physicochemical measurements are, however, time-consuming, sample destructive and expensive. Low- field 1 H nuclear magnetic resonance is a rapid, noninvasive method to investigate water mobility within materials and foods. The method showed strong correlations with various physicochemical properties, which are important quality factors during shrimp processing. Moreover, the techniques are fast, reliable and nonsample destructive. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the possibility of differentiating the botanical origin of honeys using Low Field Nuclear Magnetic Resonance (LF 1H NMR). Eighty samples of honey from 8 different botanical sources (eucalyptus, “assa-lipto”, oranges, Barbados cherry, cashew tree, “assa-peixe”, “cipó-uva” and polyfloral) were analyzed. A close correlation (p < 0.01) was established between the LF 1H NMR analysis and physical and chemical measurements, including water content, water activity, pH and color. Bi-exponential fitting of the transverse relaxation (T2) data revealed two water populations in all samples, T21 and T22, corresponding to relaxation times of 0.6–1.8 ms and 2.3–5.4 ms respectively. The observed differences in the relaxation times suggest that these were influenced by the differences in botanical origins. Good linear correlations were observed between the T2 and T21 parameters and the physical and chemical data. This study demonstrated that LF 1H NMR can be a viable technique for use in classifying honeys by their botanical origin. [Copyright &y& Elsevier]