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.

Lipid characteristics of subcutaneous adipose tissue and M. longissimus thoracis of Angus and Wagyu steers fed to US and Japanese endpoints.

We hypothesized that the concentrations of monounsaturated fatty acids (MUFA) and cholesterol of adipose tissue and M. longissimus thoracis would not differ between Angus and American Wagyu steers when fed to a typical US live weight, but would diverge when fed to a Japanese live weight. To test this, 8 steers of each breed type were assigned to a high-energy, corn-based diet, and another 8 steers of each breed type were fed coastal bermuda grass hay diet, supplemented with the corn-based diet to achieve a daily gain of 0.9kg/d. Targeted final body weights were 525kg for steers fed for 8 or 12mo the corn- or hay-based diets, respectively, and were 650kg for steers fed for 16 or 20mo the corn- or hay-based diets. Digesta concentrations of stearic (18:0) and trans-vaccenic acid decreased, whereas linoleic acid (18:2n-6) increased between the US and Japanese endpoints (all P⩽0.03). α-Linolenic acid (18:3n-3) increased in digesta only in the hay-fed steers during this time. Plasma concentrations of palmitic (16:0) and palmitoleic acid (16:1n-7), and the 16:1:18:0 ratio, were higher in Angus steers than in Wagyu steers. Also, the plasma 16:1:18:0 ratio was decreased by hay feeding in Angus steers, but increased in Wagyu steers, when fed to the Japanese endpoint. Concentrations of oleic (18:1n-9), linoleic, α-linolenic, and 18:2trans-10,cis-12 conjugated linoleic acid all were higher in Wagyu than in Angus subcutaneous (s.c.) adipose tissue, whereas myristic (14:0) and palmitic acid were higher in Angus s.c. adipose tissue (P⩽0.05). All MUFA increased, and saturated fatty acids decreased, between the US and Japanese endpoints. Slip points of lipids in s.c. adipose tissue were over 10°C lower (P=0.01) in Japanese-endpoint steers than in US endpoint steers, consistent with the overall increase in MUFA with time on feed. The concentration of cholesterol in the M. longissimus thoracis increased with time, which may have been related to the increase in oleic acid. Because the breed×endpoint interaction was not significant for cholesterol or any of the adipose tissue fatty acids, we conclude that our original hypothesis was incorrect. Of the three factors tested (breed type, diet, and slaughter age endpoint), endpoint had the greatest effect on adipose tissue lipid composition.