SODIUM LACTATE AND SODIUM TRIPOLYPHOSPHATE EFFECTS ON OXIDATIVE STABILITY AND SENSORY PROPERTIES OF PRECOOKED REDUCED-FAT PORK SAUSAGE WITH CARRAGEENAN

One 40%-fat, three 10%-fat, and three 17%-fat ground pork sausage products were manufactured. Within each reduced-fat level, these products contained 0.5% carrageenan, carrageenan and 3% sodium lactate (SL), and carrageenan, SL and 0.25% sodium tripolyphosphate (SP). Precooked patties packaged with oxygen-permeable PVC film were stored at 4C and −20C for up to 6 days and 252 days, respectively. Vacuum-packaged patties were stored up to 84 days and 252 days at the respective temperatures. All reduced-fat products were harder, more dense, and less juicy than the 40%-fat product. Total aerobic microbial plate counts determined on PVC-packaged samples stored at 4C were similar among the 7 products. SL acted as a prooxidant as evaluated by 2-thiobarbituric acid values. SP used with SL tended to overcome the prooxidive effect of SL but increased springiness, hardness, and fracturability sensory scores.     

THE EFFECTS OF MEAT TYPE AND FORMULATION ON THE PHYSICAL PROPERTIES AND SENSORY CHARACTERISTICS OF NONSPECIFIC MEAT LOAVES

Processing and sensory characteristics of meat loaves prepared from CB, CBS, HB and HBS meats and formulated with varying levels of fat (30 and 40%) and added water (120 and 130%) were evaluated. Muscle pH values were observed to be the highest for HB raw materials and lowest for CBS materials. Loaves prepared from HB and HBS meats exhibited less cook loss. Higher levels of added water resulted in a greater amount of fat and moisture loss during cooking. Loaves formulated at the 30% fat level exhibited a more desirable color and were superior in sensory characteristics when compared with loaves formulated to the 40% fat level.     

SODIUM LACTATE EFFECTS ON MICROBIAL, SENSORY, AND PHYSICAL CHARACTERISTICS OF VACUUM-PACKAGED PORK SAUSAGE

Vacuum-packaged fresh meat products held at refrigeration temperatures have limited shelf-life expectancies, often due to growth of anaerobic lactic acid-producing bacteria. Agents that can suppress the growth of this group are beneficial. Fresh pork sausage, formulated to contain 0%, 1%, 2%, or 3% sodium lactate (SL), was vacuum packaged and stored at 4C for 0, 10, 17, 24, and 31 days. A trained sensory panel evaluated pork, salty, sour, and bitter flavors. Aerobic total plate counts (APC), anaerobic total plate counts (AnPC), aerobic lactic acid producers (ALC), anaerobic lactic acid producers (AnLC), TBA values, and pH were determined. SL depressed APC, AnPC, and AnLC. Addition of 1% SL extended shelf-life of vacuum-packaged fresh pork sausage by 1 week compared to controls; samples containing 2% and 3% SL had not reached spoilage level (log₁₀ 7.0 CFU/g) at the conclusion of this study. Addition of SL increased salty taste and prevented loss of pork flavor over time, but had no effect on sour or bitter flavors.     

AGING AND COOKING EFFECTS ON SENSORY TRAITS OF PORK FROM PIGS OF DIFFERENT BREED LINES

The effects of postmortem aging time (2, 9, and 16 days) and endpoint cooking temperature (60, 70, and 80C) on the eating characteristics of pork longissimus (LD) muscle were evaluated. Gilts (n=60) were from 4 different commercial hybrid genotypes (15 pigs/genotype) selected to produce a range of intramuscular fat. Results suggest that LD muscle from genotype 2, which was selected for its propensity to increase marbling had higher intramuscular fat content, tenderness and juiciness scores than that from the other genotypes (P < 0.05). Increasing aging time from 2 to 16 days increased sensory juiciness and tenderness, and decreased instrumental shear force and cooking loss (P < 0.05). Aging for nine days decreased shear force (P < 0.05) but had no effect on tenderness and juiciness scores and cooking loss when compared to 2 days aging. Increasing endpoint temperature increased cooking loss and shear force, and decreased tenderness (P < 0.05) and juiciness.     

STRUCTURAL FUNCTIONS OF TASTE IN THE SUGAR SERIES: EFFECTS OF AGLYCONES ON THE SENSORY PROPERTIES OF SIMPLE GLYCOSIDE STRUCTURES

Reports the sensory properties of a number of glycosides of increasing chain length and size of aglycones, all in the favored Cl conformation. Shows bitterness appears to increase in intensity as molecular weight of the aglycone increases. Hydroxy functions which contribute to the intense sweetness of β-D-fructopyranose are also discussed     

EFFECTS OF INFESTATION BY BRUCHID BEETLES (CALLOSOBRUCHUS MACULATUS) ON THE NUTRITIONAL QUALITY AND SENSORY PROPERTIES OF COWPEAS (VIGNA UNGUICULATA)

The effects of insect infestation by Callosobruchus maculatus (Fabricus) on the chemical, nutritional and sensory properties of three cowpea varieties were investigated. Proximate analysis showed that infestation led to an increase in moisture content of seeds by 28.6% on the average. Decreases of 10.6%, 46.5% and 11.4% in crude protein, ash and soluble carbohydrate contents, respectively, were observed. For the three cowpea varieties, the minerals sodium, calcium and magnesium decreased by 6.7%, 10.0% and 1.3%, respectively. Indices of fat deterioration, peroxide value and free fatty acids, increased by 175% and 242%, respectively. Infestation decreased the weight gain, Protein Efficiency Ratio (PER), Feed Efficiency Ratio (FER) and blood glucose levels of experimental rats by 28.5%, 19%, 63.5% and 1.46%, respectively. Infestation also led to significant deterioration of the sensory attributes of food products developed from cowpeas. The color, aroma, taste and texture of these cowpea products were less acceptable than the sensory parameters of products made with uninfested cowpeas .     

THE EFFECT OF RACTOPAMINE AND INTRAMUSCULAR FAT CONTENT ON SENSORY ATTRIBUTES OF PORK FROM PIGS OF SIMILAR GENETICS

The objective of this research was to determine how marbling influences sensory properties of pork. Fresh boneless pork loins were collected from 229 barrows of the same genetic line over a 2-day period from a commercial slaughter facility. Live phase treatments included a control diet and the control diet supplemented with ractopamine (RAC) at 5 ppm for the final 28 days. Multiple 2.54-cm chops were cut for determination of proximate composition, cook loss, Warner–Bratzler shear force and sensory analysis. RAC minimally affected pH and objective color, but had no effect on other pork quality measurements. Additionally, the relationship between extractable lipid and sensory properties or shear force was weak. These results suggest that the level of intramuscular fat has little to do with the eating quality in this population of pigs.

PRACTICAL APPLICATIONS

The interest in highly marbled pork is based upon historical research that indicated increased marbling was beneficial to shear force values and sensory properties. Our research demonstrates that within a single genetic line, marbling does not dramatically affect sensory properties. Research of this type will help guide both consumers and the pork industry in a positive direction to determine factors that affect palatability and ultimately consumer satisfaction.     

EFFECTS OF INITIAL pH ON COMPOSITIONAL CHANGES AND SENSORY TRAITS OF FRENCH DRY-CURED HAMS

Fifty hams were distributed into 2 groups differing in initial pH of the Adductor muscle — one group with a pH < 6.1 (low pH group) and the other group with a pH of 6.1 or higher (high pH group). Ten hams were used for fresh meat analysis, while the 40 other hams were processed by dry-curing. Five hams of each pH group were used for chemical analysis before processing (day 0) and at days 74, 81, 179 and 273 of processing. The Biceps femoris muscle was analyzed for moisture, salt content, lipids, nitrogen fractions and volatile compounds. Sensory analysis was performed at days 179 and 273. The low pH hams had higher moisture and salt content at the beginning of processing. They reflected more active lipolysis and proteolysis as indicated by higher levels of free fatty acids and nonprotein nitrogen. Also, they were scored as firmer, dryer and had a less intense fat aroma.     

EFFECTS OF SODIUM LACTATE AND SODIUM PHOSPHATE ON THE PHYSICAL AND SENSORY CHARACTERISTICS OF PUMPED PORK LOINS

Whole, boneless pork loins were pumped to result in a final concentration of 0% to 2% sodium lactate (SL) and/or 0% to 0.4% sodium tripolyphosphate (STP) resulting in a 3 × 3 factorial design. Three replications were randomly presented to 10 trained sensory panelists for evaluation. Physical properties of the loins were also evaluated. Sensory evaluation results suggested that there was a trend for juiciness and tenderness to be enhanced by the addition of STP. Pork flavor, salt intensity, and alkalinity were enhanced by SL. Pump yields increased while purge loss was reduced with the addition of STP. Color was not affected by SL or STP. No difference in peak force and energy required to shear samples was observed. Results from this study suggest that pork loins pumped with SL and STP had enhanced moisture retention with few detrimental effects on sensory characteristics.     

HALOTHANE-GENOTYPE AND DURATION OF REFRIGERATED STORAGE EFFECTS ON THE QUALITY OF VACUUM-PACKAGED PORK LOINS

Loins (n=72) from halothane negative (NN) and carrier (Nn) pigs were vacuum-packaged and stored for 0, 3, or 6 weeks at 2C. Samples from Nn pigs had more (P<0.001) purge loss than NN-loins after 3 and 6 weeks of storage. Color scores for chops of Nn pigs were lower (P<0.001) than for the NN animals after 0 and 3 weeks; but after 6 weeks of storage, chops from Nn and NN pigs received similar American color scores. Chops from Nn pigs were lighter (P<0.001) and less (P<0.001) red than chops from the NN animals; however, L* values of chops from Nn pigs decreased, and a* values increased, from 0 to 3 weeks of storage. Although initial quality traits of chops from Nn pigs were inferior to those of NN, pork color of Nn-pigs appeared to be improved with extended storage.     

EFFECTS OF NISIN AND MODIFIED ATMOSPHERE PACKAGING (MAP) ON THE QUALITY OF EMULSION‐TYPE SAUSAGE

ABSTRACT

The aim of this work was to study the effects of nisin (30 ppm) and modified atmosphere packaging (MAP) on the chemical, microbial and sensory properties of emulsion‐type sausage stored under two different atmospheres (%CO₂/%N₂/%CO/%O₂): 39.5/60/0.5/0 and 39.5/20/0.5/40. The samples were stored at 3 ± 1C for 42 days. Microbial count, values of pH, CIE L*, a* and b* color parameters, lipid oxidation, production of nitrosomyoglobin and sensory properties were assessed throughout the storage period. The data showed that nisin was able to reduce the growth of mesophilic, psychrotrophic and lactic acid bacteria. In addition, the MAP did not show any significant effects on microbial growth. However, free O₂ MAP, in combination with nisin, reduced the growth of yeast and mold. MAP could produce a stabilized red color and minimize the oxidative reactions in the samples. Packaging conditions had no significant effect on pH and sensory properties.

PRACTICAL APPLICATIONS

The results of this study confirmed that nisin can reduce the growth rate of lactic acid bacteria, psychrotrophic and mesophilic bacteria in emulsion‐type sausage, and free O₂ MAP, in combination with nisin, inhibits the growth of yeast and mold. The use of 30 ppm nisin, in combination with MAP containing 39.5% CO₂ and 0.5% CO gases, can lead to better quality preservation of the emulsion‐type sausages stored at low temperature and can extend their shelf life.     

EFFECTS OF CHITOOLIGOSACCHARIDE ON THE PHYSICOCHEMICAL, TEXTURAL AND SENSORY PROPERTIES OF TOFU

Chitinous polymers have been experimented with for the purpose of shelf-life extension of foods due to their antimicrobial activity. Food additives, however, may impair the taste, color or texture of foods. Therefore, it is necessary to evaluate the effect of a food additive on foods before it is used. In this study, we investigated how the physicochemical properties, microstructure, textural properties and sensory characteristics of tofu are affected by the addition of chitooligosaccharide during its preparation. The addition of chitooligosaccharide to tofu did not significantly affect its physicochemical properties including moisture content, yield, turbidity and color. The chitooligosaccharide tofu, however, had lower hardness and smaller protein aggregates than the control tofu. The chitooligosaccharide did not influence most sensory attributes of tofu except for imparting a bitter taste.