Effect of enzymatic modification on frozen chicken surimi

Abstract

Stangierski J., Rezler R., Baranowska H.M., Poliszko S. (2013): Effect of enzymatic modification on frozen chicken surimi. Czech J. Food Sci., 31: 203-210.The effects were assessed of the addition of microbial origin transglutaminase (MTG) and modification time of proteins in frozen chicken surimi on its texture, rheological attributes, molecular dynamics of water, water activity, and thermal properties of proteins. Surimi was produced from mechanically separated poultry meat. The amount of 3 g/kg MTG were added to samples of fresh, frozen (stored at -22°C for 30 days), and defrosted surimi which were incubated for a max. 9 h at 15°C. The highest values of the analysed texture attributes and rheological modules were recorded in the case of the sample enzymatically modified before freezing. The values of spin-lattice relaxation time were significantly higher in the control system. In comparison to non-modified surimi, the samples treated with MTG were characterised by a considerable increase in the equilibrium water activity. After 7 h modification, the value of enthalpy for surimi protein was by approx. 30% lower in comparison to the control sample.

Low-Field NMR Study of Shortcake Biscuits with Cricket Powder, and Their Nutritional and Physical Characteristics

“…Recently, there has been increasing interest in the application of LF NMR for food analysis [ 27 , 28 ]. The main reason for that is the possibility to study different processes in model food systems, including gelatinization [ 29 , 30 ], retrogradation [ 31 ] or hydratation of starch [ 32 ], lipid oxidation [ 33 ], and enzymatic modification of proteins [ 34 ]. Moreover, it is useful in the analysis of complex food matrices, as proton fractions of water, lipids, or polysaccharides tend to form separate populations that relax at significantly different rates.…”

Water properties in pâtés enriched with potato juice

“…Detailed characteristics of the experimental method were specifically described by Stangierski et al [23]. The measurements were performed at temperature in the range of 15-60 °C.…”

“…The fact that such enrichment alternates the physicochemical and sensory properties of the base product must be taken into account [15][16][17]. As previously determined, the form in which potato juice is applied has influence on product quality [18][19][20][21]. The change in water activity value with the change of temperature is the result of the delivery the energy to the system.…”

Combined beef thawing using response surface methodology

“…As for UT, PC rises at first and then it declines. The reason is that too small power leads to a prolonged thawing time, so the molecular forces that maintain the integrity of muscle tissues are destroyed while too large power would promote the contraction of mus- (Stangierski et al 2013). As for MT, PC increases at first and then it drops because a too short work time would improve the protein unfolding while a too long work time would excessively heat the meat surfaces and reduce the solubility of post-freezing proteins, manifested as a reduction of protein extractability.…”