Effect of meat enhancement solutions with hydroxypropyl methylcellulose and konjac flour on texture and quality attributes of pale, soft, and exudative pork

The objective of this study was to determine whether addition of hydrocolloids, buffer ingredients, salt, and sodium phosphate improve the color, texture, and pH of normal and pale, soft, and exudative (PSE) meat. Specific solutions include potassium bicarbonate (KHCO), ammonium bicarbonate (NHHCO), hydroxypropyl methylcellulose (HPMC), and konjac flour (KF). Three studies were carried out. First, the stability and viscoelastic properties of the different solutions was determined. Second, fresh normal (pH 5.6-5.9) and PSE (pHu < 5.4) Longissimus dorsi muscles were ground and assigned a treatment solution: control (fresh normal), water, NaCl/SP, KHCO, NHHCO, KF, HPMC, KHCO/KF, KHCO/KF/NaCl/SP (sodium phosphate), NHHCO/HPMC, and NHHCO/HPMC/NaCl/SP. Third, treatment solutions with suitable viscoelastic properties and stability, were added, homogenized, stuffed into tubes, and cooked to an internal temperature of 75C to form gels, and torsion and texture profile analysis performed. The PSE treated samples containing bicarbonate/hydrocolloid treatments had similar hardness-first bite, hardness-second bite, and gumminess values to the normal-control samples while the NHHCO treated samples had air pockets in the cooked gel. Third, consumers (n = 92) evaluated control and PSE beef/pork frankfurters produced with the following treatments: KHCO, KHCO/HPMC, and KHCO/KF. Treatment had no effect (p > .05) on overall like/dislike of flavor, but PSE frankfurters were preferred (p < .05) to the controls. The use of KHCO with hydrocolloids, salt and SP improved the color, pH and texture properties of PSE ground pork; further research to examine the effectiveness in whole PSE pork muscle systems is needed.

PRACTICAL APPLICATIONS

Meat processors could use KHCO with HPMC or KF as ingredients to improve color, texture, and pH of PSE meat. The reduction of variation between PSE and normal pork muscle would improve pork quality and add value to PSE meat products.

Effect of Genetically Modified Feeds on Physico-Chemical Properties of Pork

The objective of this study was to evaluate the effects of genetically modified (GM), insect-resistant Bt maize (MON810) and the meal made of glyphosate-tolerant soybean (Roundup Ready MON40-3-2) used as the dietary components for pigs on the physico-chemical properties of meat. Forty-eight fatteners derived from Polish Landrace x Polish Large White sows mated to a Duroc x Pietrain boar were used. All animals received isonitrogenous and isoenergetic diets containing or not containing the genetically modified components. The design of the experiment was as follows: group I (control) - non-modified soybean meal and maize; group II - GM soybean meal and non-modified maize; group III - non-modified soybean meal and GM maize; group IV - GM soybean meal and GM maize. The examination of the pH values of loin and neck muscles indicated no statistically significant differences between pigs fed diets containing non-transgenic or transgenic feeds. No statistical differences were observed for water holding capacity (WHC) within dietary treatments. The introduction of transgenic maize and soybean meal into pig diets did not significantly affect the a* colour parameter of loin as well as neck muscles. The use of transgenic maize or soybean meal did not cause significant changes in the L* colour value of loin. Results obtained for neck muscles were more differentiated, possibly due to the natural heterogeneity of this primal cut. Pigs which had consumed the transgenic diet exhibited slightly decreased lipid stability of loin, as indicated by thiobarbituric acid reactive substances (TBARS). The decrease was statistically significant only in the case of muscles from group II. The addition of feeds derived from genetically modified crops into pig diets did not significantly affect the stability of neck muscle lipids; however, TBARS values of these muscles were twice those of loin muscles.