Quality Attributes in Shrimp Treated with Polyphosphate after Thawing and Cooking: A Study Using Physicochemical Analytical Methods and Low‐Field ¹H NMR

Abstract

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 APPLICATIONSShrimp 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.

Microbiological, physical and chemical characteristics of freshwater prawns (Macrobrachium rosenbergii) in modified‐atmosphere packaging

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Effect of severing skeletal muscle at different stage of rigor on the quality of pacific white shrimp (Litopenaeus vannamei)

“…The initial higher value (96.61%) of water holding capacity was observed in T 1 and lowest initial value (96.19%) was found in T 2 . The final lowest and the highest values of WHC were found in T 3 and T 1 , respectively The decrease in the water holding capacity may be due the denaturation of proteins (Carneiro et al, ). Water holding capacity did not show any significant difference among the treatments.…”

Application of high‐pressure argon for improving postharvest quality of cherry tomato

“…The color of cherry tomatoes was measured with a CR‐400 colorimeter (Konica Minolta, Inc., Tokyo, Japan). Lightness ( L* ), redness ( a *), and yellowness ( b *) were determined (Carneiro et al, ). Three replicates were measured.…”