Burgers were prepared using duck surimi-like material (DSLM) with polydextrose added (SL) and DSLM with sucrose-sorbitol added (SS), and the properties of these burgers were compared with those of burgers made of chicken meat (CB) and duck meat (DB). Quality characteristics such as chemical composition, cooking loss, diameter shrinkage, color, and texture were measured. The DB had a lower moisture content (55.58%) and higher fat content (21.44%) and cooking loss (11.01%) compared with other samples, whereas CB, SS, and SL did not differ significantly in moisture (65.21-66.10%) and fat (10.42-11.16%) content or cooking loss (5.32-6.15%). The SS and SL were positioned below CB and above DB in terms of hardness, chewiness, and springiness. Ten trained panelists assessed the burgers using quantitative descriptive analysis. Among the burgers, CB had the greatest brightness of color, hardness, springiness, and chewiness. The SS had greater sweetness than the other burgers. Both SL and SS had significantly less animalic odor, meaty flavor, oiliness, juiciness, and saltiness compared with DB. The physicochemical and sensory characteristics of burgers prepared from DSLM approached those of burgers made of chicken.
Nine formulations were processed into bologna with different ratios of soy protein isolate (SPI):sodium caseinate (SCA), i.e. 1:1, 1:2.5, 1:5, 5:1, 5:2.5, 5:5, 10:1, 10:2.5 and 10:5. The products were evaluated for yields, emulsion stability, physical measurements (shearforce-kgf and folding test) and taste panel evaluation. Formulations with 5:1 and 5:5 SPI:SCA had lower liquid loss resulting in higher yields while the others had poor emulsion stability and high liquid loss. Firmer texture was exhibited by formulations 1:1, 5:1 and 10:1 SPI:SCA but formulation with 1:1 SPI:SCA showed better gelation followed by 1:2.5, 1:5, 5:1, and 5:2.5. The other formulations had poor gelation and binding properties, especially formulation with 10:5 SPI:SCA. Sensory evaluation was carried out using 30 untrained panelists. Attributes evaluated were aroma, texture, chewiness, juiciness, saltiness, chicken taste and overall acceptance. Formulation with 5:1 SPI:SCA was more acceptable for texture, chicken taste and overall acceptance while formulation with 1:1 SPI:SCA was more acceptable for the chewiness, juiciness and saltiness attributes. There was no significant difference (P > 0.05) in aroma attribute, for all formulations.
A test for assessing pork adulteration in meatballs, using TaqMan probe real-time polymerase chain reaction, was developed. The assay combined porcine-specific primers and TaqMan probe for the detection of a 109 bp fragment of porcine cytochrome b gene. Specificity test with 10 ng DNA of eleven different species yielded a threshold cycle (Ct) of 15.5 ± 0.20 for the pork and negative results for the others. Analysis of beef meatballs with spiked pork showed the assay can determine 100-0.01% contaminated pork with 102% PCR efficiency, high linear regression (r(2) = 0.994) and ≤ 6% relative errors. Residuals analysis revealed a high precision in all determinations. Random analysis of commercial meatballs from pork, beef, chicken, mutton and goat, yielded a Ct between 15.89 ± 0.16 and 16.37 ± 0.22 from pork meatballs and negative results from the others, showing the suitability of the assay to determine pork in commercial meatballs with a high accuracy and precision.
Research was conducted to manufacture and evaluate a restructured turkey breast product using the Fibrimex cold-set binding system, sodium diacetate (NaD), and sodium lactate (NaL) and to ascertain effects of the treatments on proximate composition, pH, psychrotrophic organisms, water activity, onset of rancidity (TBA), thaw loss, cooking yields, and objective color, and sensory characteristics. Whole turkey breasts were cut into 5-cm-thick strips; treated with either water only (control), 1.5% NaL, 2.0% NaL, 0.1% NaD, 1.5% NaL + 0.1% NaD, or 2.0% NaL + 0.1% NaD; blended with Fibrimex ingredients; stuffed into casings; and stored at -30 degrees C for 0, 1, 2, and 3 mo. After each storage period, frozen chubs were tempered at 4 degrees C, sliced into 1-cm-thick steaks, packaged in retail trays, stored at 0 degrees C to simulate retail storage, and analyzed after 0, 2, 4, 6, 8, and 10 d. Sodium diacetate used alone or in combination with NaL reduced (P < 0.05) growth of psychrotrophic organisms and had no adverse effects on water activity, pH, cooking yield, fat, moisture, protein, objective color, onset of rancidity, and sensory characteristics (juiciness, turkey flavor intensity, and tenderness). Panelists reported slight off-flavor in all steaks treated with NaL. Treating steaks with NaL alone or in combination with NaD resulted in increased (P < 0.05) ash content. Sodium lactate also functioned to minimize thaw loss in the frozen restructured turkey product.
Replacement of beef by buffalo and vice versa is frequent in global markets, but their authentication is challenging in processed foods due to the fragmentation of most biomarkers including DNA. The shortening of target sequences through use of two target sites might ameliorate assay reliability because it is highly unlikely that both targets will be lost during food processing. For the first time, we report a tetraplex polymerase chain reaction (PCR) assay targeting two different DNA regions in beef (106 and 120-bp) and buffalo (90 and 138-bp) mitochondrial genes to discriminate beef and buffalo in processed foods. All targets were stable under boiling, autoclaving and microwave cooking conditions. A survey in Malaysian markets revealed 71% beef curries contained buffalo but there was no buffalo in beef burgers. The assay detected down to 0.01ng DNA and 1% meat in admixed and burger products.