<strong>Dried</strong> plum ingredients in pork sausage . . .purees in both raw and precooked pork sausages stored either refrigeratedor frozen.Materials and MethodsManufacture of pork sausageSix 22.7-kg batches of pork sausage were formulated to containone of 6 antioxidant treatments: (1) no antioxidant (control), (2) 3%or 6% dried plum puree (DP), (3) 3% or 6% dried plum and applepuree (DPA), or (4) a BHA/BHT (crystalline, Kosher Tenox R , EastmanChemical Co., Kingsport, Tenn., U.S.A.) combination (appliedat 0.02%, based on sausage fat content). A total of 18 batches (6treatments × 3 replicates) of pork sausage were manufactured inthe entire study. DP and DPA were obtained from <strong>California</strong> PlumBoard (Sunsweet Growers Inc., Yuba City, Calif., U.S.A.). Antioxidantingredient specifications are shown in Table 1.Table 1 --- Chemical and physical specifications of antioxidantingredients used in pork sausage formulations.AntioxidantingredientsTenox R BHA PM 01787-00Tenox BHT PM 13484-00Sunsweet R dried plum puree(DP)Sunsweet lighter bake (driedplum puree + dried applepuree) (DPA)ManufacturerspecificationButlyated hydroxyanisole/025013-16-5 + citric acid/ 000077-91-9(crystalline) specimen nr 31905/002043,5-di-tert-butyl-4-hydroxytoluene/000128-37-0 (crystalline)specimen nr 31602/00225Dark brownMoisture content (30% ± 0.5%)Brix (70 ◦ minimum)pH (3.5 to 4.5)Titratable acidity 1.5 to 2.2 (as malicacid, w/w)Viscosity > 1000 cps1000 ppm maximum potassiumsorbateLight brownMoisture content (50% to 56%)Brix (48 to 52 ◦ )pH (3.5 to 4.0)Titratable acidity 0.35% to 0.55%(as malic acid, w/w)Viscosity (40000 to 60000 cps at68 ◦ F)1000 ppm maximum potassiumsorbateWater activity (0.916)Pork sausage processing was performed in a state-inspected(Texas Dept. of Health) commercial-scale pilot plant located inthe Rosenthal Meat Science and Technology Center at Texas A&MUniv. Raw well-chilled pork lean derived from boneless welltrimmedpork shoulders containing approximately 15% fat and fattrim taken from loins, bellies, and shoulders containing approximately40% fat were purchased from a commercial source 3 to4 d postmortem. Lean and fat trimmings were coarse ground separatelythrough a 1.27-cm plate. After fat analysis of the pork trimmings,Pearson’s square was used to formulate the meat block toa 32% fat endpoint (Table 2). Lean trim (7.3 kg) was combinedwith 15.4 kg of fat trim in a paddle mixer (Butcher Boy, Model 150,Lasar MFG Inc., Los Angeles, Calif., U.S.A.) to yield a 22.7-kg meatblock. Added to this meat block were 453.6 g of a spice preblend(pork sausage seasoning, AC Legg TM , Birmingham, Ala., U.S.A.),3.0% water, and the appropriate antioxidant treatment. DP and DPAproducts were incorporated directly into the mixer in their originalpuree forms. A mixture of crystalline BHA (0.01%) and BHT (0.01%)was pulverized and blended with the dry-seasoning preblend to ensureuniform distribution in the paddle mixer. All added ingredientswere mixed for 5 min and reground through a 0.635-cm plate.The pork sausage was vacuum stuffed (Model RS1040C Risco TM ,Nev Solomon Enterprises, Italy) into 908-g plastic chubs (PolyTubes 20-30-01 CP, Harbro Packaging Co., Chicago, Ill., U.S.A.) andclipped at each end with metal clips. Ten chubs of pork sausagefrom each antioxidant treatment were assigned to the raw treatment(RR) and stored at 4 ◦ C for 0, 7, 14, 21, and 28 d. A total of 1008,1-cm thick patties (168 patties per treatment) of 6.35 cm dia weresliced manually with a knife using a ruler to standardize the thicknessand plastic sleeve removed. Patties to be cooked were spacedon a foil-covered baking sheet, placed in a convection oven (HobartCorp., Troy, Ohio, U.S.A.), and cooked, without turning, for 9 minat 148.9 ◦ C to an internal temperature of 71.1 ◦ C. Internal temperaturewas monitored with type T thermocouple (Omega ModelHH21, Omega Engineering Inc., Stanford, Conn., U.S.A.) insertedinto the geometric center of random patties. After cooking, pattieswere cooled (4 ◦ C) and vacuum packaged (Ultravac R 2100, KOCHInc., Kansas City, Mo., U.S.A.) in Cryovac R (Cryovac North America,Duncan, S.C., U.S.A.) BW540 bags to 20 mm Hg. A constantvacuum (20 mm Hg) was used to avoid compressing or distortingthe patties in the package and to maintain a constant, yet low levelof ambient air. At 20 mm Hg, a constant amount of air remainedin the package for some promotion of oxidation to challenge theantioxidant treatments. Twenty-one precooked patties from eachtreatment were assigned to each package and used for subsequentanalysis. Five vacuum packages of precooked pork sausage patties(PR) from each antioxidant treatment were packed into cardboardH: Health, Nutrition, &FoodTable 2 --- Pork sausage formulations by antioxidant treatments.IngredientsControl BHA/BHT DP 3% DP 6% DPA 3% DPA 6%Meat blockPork lean trimmings (kg) 85/15 (lean/fat) 7.3 7.3 7.3 7.3 7.3 7.3Pork fat trimmings (kg) 60/40 (lean/fat) 15.4 15.4 15.4 15.4 15.4 15.4Pork sausage seasoning blend (kg) (salt, 0.4536 0.4536 0.4536 0.4536 0.4536 0.4536red pepper, sage, sugar, black pepper)<strong>Dried</strong> plum puree (DP) (kg) --- --- 0.68 1.36 --- ---<strong>Dried</strong> plum/apple puree (DPA) (kg) --- --- --- --- 0.68 1.36BHA/BHT a (g) --- 1.45 --- --- --- ---Water (3% of meat block) (kg) 0.68 0.68 0.68 0.68 0.68 0.68Total (kg) 23.83 23.84 24.51 25.19 24.51 25.19a Crystalline BHA and BHT were powdered and blended with the pork sausage seasoning blend to ensure uniform distribution of the antioxidant during mixing of themeat block.H64 JOURNAL OF FOOD SCIENCE—Vol. 73, Nr. 5, 2008
<strong>Dried</strong> plum ingredients in pork sausage . . .boxes and stored in the dark at 4 ◦ C for 0, 7, 14, 21, and 28 d, while3 vacuum packages per treatment were assigned to the precooked,frozen (PF) treatment and stored at –20 ◦ C for 30, 60, and 90 d.Proximate analysisPercentages of moisture (AOAC 950.46), fat (AOAC 985.15), andprotein (AOAC 992.15) were determined on raw pork sausage fromeach antioxidant treatment according to AOAC (2000) procedures.Raw patties from each antioxidant treatment at day 0 were homogenizedin a food processor (Model DLC-8M, Cuisinart Inc., Norwich,Conn., U.S.A.) before sampling. Percentages of moisture andfat were determined using the convection air-dry oven and Soxhletether extraction methods, respectively. Crude protein percentagewas determined by Dumas combustion method for gaseousN 2 using a Leco FP-528 protein analyzer (St. Joseph, Mo., U.S.A.).The instrument was standardized with ethylenediamine tetraaceticacid (EDTA) (part nr 502-092, %N = 9.56 ± 0.04) and Orchard leaves(part nr 502-055, %N = 2.4 ± 0.4) after each block of 10 to 12 samples.Crude protein percentage was calculated as 6.25 times the percentnitrogen.Cook yieldSix 1-cm-thick raw pork sausages patties from each antioxidanttreatment were weighed and cooked as described previously. Pattieswere allowed to cool to room temperature, reweighed, and theweight recorded. The percentage of cooking yield was determinedby dividing the cooked product weight by the raw product weightand multiplying by 100.Color evaluationLab color space values (L ∗ , a ∗ , and b ∗ ) of the inner and outer surfacesof raw pork sausage chubs from each antioxidant treatmentwere obtained by reflectance using a Minolta Colorimeter (ModelCR-300, Minolta Co., Ramsey, N.J., U.S.A.) with an 8-mm viewingport and illuminant D 65 . Chubs of pork sausage from each antioxidanttreatment, assigned to the RR and stored at 4 ◦ C for 0, 7, 14,21, and 28 d, were opened and allowed to bloom for a minimumof 30 min prior to color determination on the outer surface. Then,patties from chubs were sliced 6.35 cm thick and the inner surfacewas measured after 10 min. The colorimeter was calibrated daily toa standard white tile surface (L ∗ = 96.66, a ∗ = –0.03, and b ∗ = 1.61)at channel 00. The colorimeter port was covered with Saran R Wrapand then calibrated, and random readings were taken at 6 separatelocations on the inner surface and outer surface of each treatment.The measurements were averaged for each surface and the resultswere expressed as positive L ∗ (lightness), a ∗ (redness), and b ∗ (yellowness)values.Lipid oxidation2-Thiobarbituric acid-reactive substance (TBARS) content of thepork sausage patties from each treatment (antioxidant treatment ×storage treatment × storage day) was determined using the TBAdistillation procedure of Tarladgis and others (1960) as modified byRhee (1978). TBARS values for each sample were reported on a sampleweight basis (TBARS = mg malonaldehyde/kg sample).Allo-Kramer shear forceShear force determinations were performed as described by Linand Keeton (1994). Allo-Kramer shear force measurements wereperformed on five 10-mm thick patties from each antioxidant treatmentstorage combination. RR samples were cooked in a convectionoven for 9 min at 148.9 ◦ C to an internal temperature of71.1 ◦ C and allowed to cool to room temperature. PR and PF sampleswere reheated for 7 min at 93.3 ◦ C to an internal temperatureof 62.8 ◦ C and allowed to cool to room temperature. Pattieswere weighed and sheared using an Instron universal testing machine(Model 1011, Instron Corp., Houston, Tex., U.S.A.) equippedwith a 10-blade Allo-Kramer shear compression using a 500-kg loadcell with a 100-kg load range and a 500-mm/min crosshead speed.Kilograms of shear force were recorded and divided by the sampleweight to determine the shear force in kilograms per gram ofsample.Descriptive attribute and consumersensory evaluationsPork sausage samples from each treatment (antioxidant treatment× storage treatment × storage day) were evaluated by a7-member trained expert descriptive attribute sensory panel in theTexas A&M Univ. Sensory Testing Facility. The panelists were selectedand trained according to the procedures of Cross and others(1978), AMSA (1995), and Meilgaard and others (1999). All panelistshad more than 5 y of experience in Spectrum TM descriptive flavorand texture analysis (Meilgaard and others 1999). Panelists underwentballot development and training sessions using pork sausagewithout antioxidant (control “as is”) and pork sausage with antioxidanttreatments (3% or 6% DP, 3% or 6% DPA, and BHA/BHT).Panel-specific training was conducted for 6 d. Panelists underwentperformance evaluation as specified in the guidelines developed byAMSA (1995) prior to initiation of the study to assure that the panelistswere sufficiently trained. The samples were evaluated for flavor(cooked pork/brothy, cooked pork fat, spicy/peppery, soured,cardboard, painty, fishy, prune/plum, sage, brown/burnt, and vinegar),feeling factors (metallic and astringent), basic tastes (salt, sour,bitter, and sweet), mouth feel (pepper burn), aftertastes (sage, pepper,salt, sweet, prune, and sour), and texture attributes (hardness,springiness, juiciness, cohesiveness, denseness, and fracturability)as defined in Table 3.All samples were scored using the 0 to 15 Spectrum universalintensity scale (Meilgaard and others 1999) where 0 = absence ofan attribute and 15 = extremely intense. In addition, panelists alsoevaluated texture (springiness, juiciness, hardness, cohesiveness,and denseness) using the 0 to 15 Spectrum universal intensity scalewhere 0 = not springy, dry, soft, crumbly, and airy, and 15 = veryspringy, juicy, hard, defined p<strong>article</strong> size, and dense, for each attribute.Warm 13 mm cubed samples were served to the panelists.The order of the treatments was randomized and a fresh warmupsample was presented to judges before the sample evaluationto ensure that they were familiar with the treatment attributes tobe tested. The stimuli used for warm-up were pork sausage froma control formulation. The samples were coded with a random3-digit number to mask the treatment identity and placed in clear6-oz sample cups with lids. Each panelist received at least 2 cubes(13 mm) per sample and evaluated 12 randomly ordered RR orPR samples per day (0, 7, 14, or 21 d) and 6 randomly ordered PFsamples (30, 60, or 90 d). Panelists evaluated samples in isolatedbooths fitted with a breadbox server and red incandescent lightingto mask color differences. Distilled water at room temperature, unsaltedcrackers, and ricotta cheese were given to judges to cleansethe palate between treatments.To evaluate the acceptability of pork sausage samples fromeach antioxidant treatment (control, 3% or 6% PP, 3% or 6% DPA,and BHA/BHT), randomly ordered samples were evaluated by aconsumer panel (118 participants) according to the proceduresdefined by Meilgaard and others (1999). The consumer samplepopulation was selected from students and staff in the AnimalH: Health, Nutrition, &FoodVol. 73, Nr. 5, 2008—JOURNAL OF FOOD SCIENCEH65
Change language