Warmed-over Flavor Research Articles

Assessment of off‐flavor development in restructured chicken nuggets using hexanal and TBARS measurements and sensory evaluation

AbstractThe hexanal contents of chicken nuggets treated with various anti‐oxidants were evaluated in relation to the development of warmed‐over flavor (WOF) during frozen storage. Of the antioxidant treatments tested, the sodium tripolyphosphate (STPP)/tertiary butylhydroquinone combination showed the greatest effect by decreasing hexanal production by 95%. Combinations of STPP/oleoresin rosemary, (0.5 g kg−1 and 1 g kg−1) decreased the hexanal contents by 85% and 91%, respectively. A higher correlation coefficient (pooled, within treatments) between hexanal contents and sensory scores for WOF (r = 0.68) relative to that between hexanal contents and thiobarbituric acid reactive substances values (r = 0.14) was obtained. A pooled, correlation coefficient within treatments and storage times (r = 0.56), was found between TBARS and sensory scores. It was concluded that the use of correlation coefficients calculated without pooling groups of data within each significant experimental factor to interrelate the results of different analyses may be inappropriate.

DEXTROSE LEVEL AND OVEN TEMPERATURE EFFECTS ON WARMED‐OVER FLAVOR DEVELOPMENT IN BEEF TOP ROUND ROASTS1,2

ABSTRACTTo determine the effect of added dextrose and cooking temperature on the development of warmed‐over flavor (WOF) and thiobarbituric acid reactive substances (TBARS), beef top round roasts were injected with a basic brine solution containing salt and sodium tripolyphosphate along with 0, 1 or 2% dextrose. The roasts were cooked in an oven temperature of 121C or 191C and stored for 4 weeks. Roasts cooked at the faster rate, without the addition of dextrose, showed TBARS values to be higher (P < 0.05) than those cooked at a slower rate. However, the addition of dextrose to roasts cooked at the faster rate reduced (P < 0.05) TBARS values. When 2% dextrose was added to roasts cooked at the slower rate, an increase (P < 0.05) in TBARS was observed. The addition of dextrose to beef top round roasts can reduce TBARS values when the roasts are cooked at relatively high temperatures, but may cause an increase in TBARS values when cooked at slower rates of heating.

Antioxidant synergism between tocopherols and ascorbyl palmitate in cooked, minced turkey

In an attempt to reduce oxidative deterioration, including the development of warmed-over flavour (WOF), in cooked, minced turkey meat, a combined strategy using natural antioxidants and modified atmosphere packaging (MAP) was adapted. Tocopherols (200 ppm) each significantly reduced lipid oxidation during 9 days of cold storage (5 degrees C), measured as 2-thiobarbituric-acid-reactive substances (TBARS). Synergism between the two antioxidants was demonstrated as an increasing relative reduction in TBARS values over time when both antioxidants were added, as opposed to the almost constant relative reduction when only one antioxidant was added. Notably, this synergism depended on the availability of O2, and was found to be most significant for atmospheric packaging (21% O2, 79% N2) and most significant towards the end of the storage period. A reduced O2 content in the packages (mixture of O2 and N2, initially: 1.0% O2 or 0.03% O2) had a more pronouced effect on oxidative deterioration than addition of antioxidants. However, during the 9 days of storage, meat balls with the synergistic mixture added, and packed in 1% O2, had TBARS values of 50 compared to 270 mumol malondialdehyde/kg for meat balls without antioxidants packed in 21% O2. This level of reduction in lipid oxidation is comparable with that of meat balls without antioxidants packed in a virtually O2-free atmosphere.

The combined effect of rosemary (Rosmarinus officinalis L.) and modified atmosphere packaging as protection against warmed over flavour in cooked minced pork meat

Rosemary (dried leaves ofRosmarinus officinalis L.) added to cooked meat balls (minced pork) was found to retard the formation of warmed over flavour (WOF) during chill storage. The spice was added to pork meat (Longissimus dorsi) balls in an amount acceptable for the product, as evaluated by a sensory panel (0.05% of total weight). After cooking (water bath, internal temperature 80°C), the meat balls were packed using five atmosphere packaging conditions: (i) air; (ii) 5% O2/95% N2; (iii) 3% O2/97% N2; (iv) 1% O2/99% N2; and (v) 100% N2. During chill storage (5°C), the sensory quality of the reheated meat balls was evaluated by a trained sensory panel, and lipid oxidation was followed by measurement of thiobarbituric acid reactive substances (TBARS). The combination of decreased O2 atmosphere in the packages and addition of rosemary resulted in a significantly (p<0.05) lower amount of TBARS and a significantly (p<0.05) better sensory score.

The use of rosemary extracts to improve the flavor of precooked low fat ground beef patties

Reduced fat meat products are readily available in the marketplace. Precooked beef patties are used by foodservice establishments for their convenience but the quality of these products may be lower due to warmed-over flavor. The objective of this study was to determine if the fat content of precooked ground beef patties has an effect on the development of warmed-over flavor (WOF) and to determine if WOF could be reduced by using rosemary antioxidants. Ground beef patties (70, 80 and 90% lean) were formed into 100g patties, grilled to an internal temperature of 72°C and stored for 9 days at 4°C. Herbalock type D-20 (Kalsec, Inc.) was added at 0.45 percent (w/w). The thiobarbituric acid test (TBA) and gas chromatographic headspace analysis were performed to determine the extent of lipid oxidation. All patties with rosemary antioxidants had lower TBARS (thiobarbituric acid reactive substances) than those patties without rosemary. After 9 days of refrigerated storage TBARS for the patties with no antioxidant averaged 7.7 ± 1.6 mg/kg while the patties containing rosemary averaged 3.6 ± 1.1 mg/kg. Headspace analysis of volatile development supported this data with lower total area of volatiles for the patties with the rosemary antioxidant. No difference was found among the patties with the three levels of fat when no antioxidant was present. However, when rosemary was added, the lowest TBARS and total volatiles were found with the 90% lean patties. Fat content does affect the development of warmed-over flavor with the lower fat content patties developing less warmed-over flavor but only when a rosemary extract was used.

Effects of heat treatment on warmed-over flavour in ground beef during aerobic chill storage

The effect of heat-treatment conditions (end-point temperature and rate) on warmed-over flavour (WOF) development in ground beef during aerobic chill storage was examined. Quantification of WOF was determined by extraction of thiobarbituric-acid-reactive substances (TBARS), which were correlated with scores obtained by a sensory panel. The effect of end-point temperature, heating rate and chill-storage time on TBARS is described by a mathematical model based on first-order kinetics. The model predicts increasing levels of TBARS with increasing end-point temperature (60–80° C), increasing heating time and chill-storage time. The model can be used for optimizing processing conditions of heat-treated meat products.

Effect of packaging and storage conditions on development of warmed-over flavour in sliced, cooked meat

The development of warmed-over flavour (WOF) in a pilot-scale experiment was followed by sensory evaluation and three objective methods (thiobarbituric acid reactive substances, relative hexanal content, and fluorescent lipid oxidation products) during 14 days of chill storage at 4° C of sliced, cooked lean beef using three different packaging conditions: (1) in air in a polyethylene foil (PE); (2) in 99% vacuum in a laminate foil with low oxygen transmission rate (VAC); (3) in a modified atmosphere (30% CO2/70% N2) in a laminate foil with low oxygen transmission rate (MAP). Each of the objective methods correlated well with the sensory evaluation. The sensory quality of the meat packed in PE was clearly inferior to the VAC and MAP packed meat, having less meat taste and a perceptible degree of WOF when reheated after only 1 day of storage, increasing to an unacceptable level within 3 days of storage. In contrast, the sensory quality of the VAC and MAP packed meat remained high throughout the storage period. Irrespective of packaging method, no effect of light during the chill storage period on the development of WOF was detected. MAP packaging for precooked beef was tested on a larger scale in a senior citizen food service system. The results showed that in a practical application of MAP the major problem in avoiding WOF was the achievement of a sufficiently low residual oxygen content in the packages.

Physical and Sensory Characteristics of Fresh Pork Leg Roasts Cooked at Low Temperatures

ABSTRACTThe effects of oven temperatures of 82, 93, 121 and 163°C were studied using 31 fresh pork leg roasts cooked to 74°C in oven bags. Warmed‐over‐flavor (WOF) was measured by sensory analysis after holding 3 hr at 68°C and after holding 24 hr at 2°C and then reheating to 68°C prior to serving. Roasts cooked at 82 and 93°C tended to have less WOF after refrigeration and reheating than roasts cooked at 121 and 163°C. Roasts cooked at 93°C had fewer aerobic mesophilic bacteria than those cooked at 121 and 163°C. In general, objective and sensory perception measurements indicated that roasts cooked at 82 and 93°C were of higher quality.

Warmed-over flavour in cooked sliced beef Chemical analysis in relation to sensory evaluation

A technique for analysing the extent of warmed-over flavour (WOF) in cooked beef based on autofluorescence of the extracted lipid fraction has been studied. In a chill storage experiment with reheated, oven-cooked beef, the method has been used together with the commonly used determination of thiobarbituric acid reactive substances (TBARS) by extraction, to measure the development of WOF. The objective measurements were correlated to sensory evaluations showing that the TBARS and the fluorescence methods are each suitable for monitoring the development of WOF in reheated cooked beef during storage. However, determination of TBARS was found to agree more precisely with the sensory evaluation than the fluorescence analysis. The impression of WOF smell becomes saturated for high TBARS values and high concentrations of fluorescent oxidation products, and constitutes an example of Weber-Fechner's law describing sensory impression as a logarithmic function of the triggering compound(s). A practical implication of this result is that a doubling of the TBARS value corresponds to a 30% increase in the degree of WOF.

Response of beef flavor to oxygen depletion and an antioxidant-chelator mixture

Meat flavor deterioration (MFD) is characterized by increased levels of off-flavor sensory characteristics and by a decline in desirable-flavor attributes. MFD, long associated with the process of warmed-over flavor development in meat products, is attributed to the free-radical reactions that occur as a result of lipid peroxidation. Data is presented showing the effect of these mechanisms on meat flavor and chemistry. Data demonstrate that several mechanisms act synergistically to remove desirable flavors and heighten off-flavor development

COMPARISON OF BATTER-BREADED BEEF NUGGETS DEEP-FRIED IN COTTONSEED AND SOYBEAN OILS AND LIQUID SHORTENINGS

Restructured beef nuggets were batter-breaded and deep-fried in commercial cottonseed oil (CO), cottonseed liquid shortening (CLS), soybean oil (SO) and soybean liquid shortening (SLS) and stored at 4C for 0 or 4 days. Weight losses during frying and reheating were not significantly influenced by the frying medium used. No major sensory differences were noted among the different products except that, on day-0, nuggets fried in SLS had a “slight” warmed-over flavor due to the reversion flavor of the frying medium itself. On day-0, nuggets fried in CO or CLS had lower TBA values than those fried in SO or SLS. However, on day-4, nuggets fried in CLS or SLS had lower TBA values than nuggets fried in CO or SO. CLS may be the frying medium of choice among the four because of its ability to resist lipid oxidation in both fresh fried and stored nuggets.

Glucose and Internal Cooking Temperature Effects on Low Fat, Pre‐ and Post‐Rigor, Restructured Beef Roasts

ABSTRACTMuscles were excised pre‐rigor (hot‐boned, HB) or post‐rigor (conventionally boned, CB), chunked, and were subjected to four ingredient treatments: (SPE) 2% NaCl, 0.5% NaCl, 0.5% phosphate, 2% glucose (SP 2% NaCl, 0.5% phosphate (SG) 2% NaCl, 2% glucose and (PG) 0.5% phosphate, 2% glucose to produce low fat, restructured, beef roasts, which were cooked to an internal temperature of 63 or 93°C. Addition of glucose to a salt and phosphate (LEM‐O‐FOS1) ingredient treatment as well as cooking to 93°C helped maintain low warmed‐over flavor (WOF) scores and kept thiobarbituric acid values below threshold (&lt; 1.0) while maintaining desirable consumer acceptability scores.

Effect of different cooking methods on warmed-over flavour development in pork

Warmed-over flavour in cooked stored pork results from the oxidation of lipids during cooking. Cooking methods and temperature-time profiles of cooking significantly influenced the intensity of warmed-over flavour. It could not be strongly related with alterations in thiobarbituric acid (TBA) numbers. Microwave cooking was found to produce the maximum warmed-over flavour compared to other methods such as pan-frying, grilling, and conventional cooking in water. Heating meat to high temperatures, as happens in grilling or pan-frying, caused browning. The resultant changes in flavour either masked or retarded the formation of compounds causing off-smells during refrigerated storage of cooked pork.

Potent odorants causing the warmed-over flavour in boiled beef

The flavour compounds showing higher odour units resulting from peroxidation of unsaturated fatty acids were analysed comparatively in freshly boiled beef and in a stored (48 h, 4° C) sample exhibiting warmed-over flavour. The results obtained by aroma extract dilution analysis revealed that this flavour was mainly caused by hexanal, 1-octen-3-one, (E)- and (Z)-2-octenal, (Z)-2-nonenal, (E, E)-2,4-nonadienal andtrans-4,5-epoiiy-(E)-2-decenal.

Inhibition of Warmed‐over Flavor Development by Polyvalent Cations

ABSTRACTDuring cooking and storage of chicken significant quantities of free iron were released. Apparently iron bound to negatively charged phospholipids and caused site‐specific oxidation that generated warmed‐over flavor (WOF) within 24 hr of refrigerated storage. Iron sequestration by chelation with phytic acid greatly reduced formation of WOF. Similarly, competitive displacement of iron from phospholipids with polyvalent cations substantially lowered the rate of WOF formation. In a phospholipid model system, 25 mM Ca2+ caused 50% inhibition of malondialdehyde generation. Much lower levels were required to effectively reduce WOF development in precooked poultry. Nitrite completely blocked iron release from heme‐proteins, which explained its inhibitory effect on WOF development.

Chemical and Sensory Studies of Antioxidant‐Treated Beef

ABSTRACTGround beef patties treated with metal chelators, free radical scavengers, rosemary and sodium alginate were examined by chemical (TBARS and gas chromatography) and sensory means in regard to warmed‐over flavor (WOF). A highly trained analytical sensory panel evaluated the patties for desirable descriptors, such as cooked beef brothy (CBB) and for WOF descriptors, painty and cardboardy. Results showed many of the compounds retarded lipid oxidation when judged by chemical means, but not all affected development of WOF when judged by sensory means since CBB values decreased and WOF descriptors increased. The free radical scavengers appeared overall the most effective inhibitors of WOF.

Analysis of Volatiles Related to Warmed over Flavor of Cooked Chevon

ABSTRACTThe development of warmed over flavor (WOF) in cooked chevon was monitored from its Tenax trapped volatiles by direct gas chromatography (GC). WOF markers, pentanal, hexanal, heptanal, 2,‐3‐octanedione and nonanal were identified from volatile profiles obtained with packed poly MPE coated Tenax‐GC column. These volatile markers as well as the total volatiles increased over 6 days storage of cooked chevon at 4°C. Increase in hexanal was more rapid than the other WOF markers. Results suggest WOF development in cooked chevon is more rapid than reported rates for other cooked meats.

Prevention of warmed-over flavor in cooked beef: effect of phosphate type, phosphate concentration, a lemon juice/phosphate blend, and beef extract

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPrevention of warmed-over flavor in cooked beef: effect of phosphate type, phosphate concentration, a lemon juice/phosphate blend, and beef extractGraham R. Trout and Susan DaleCite this: J. Agric. Food Chem. 1990, 38, 3, 665–669Publication Date (Print):March 1, 1990Publication History Published online1 May 2002Published inissue 1 March 1990https://doi.org/10.1021/jf00093a017RIGHTS & PERMISSIONSArticle Views305Altmetric-Citations49LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (684 KB) Get e-Alerts Get e-Alerts

Metal recovery using chitosan.

Chitosan is a natural polycationic polymer which possesses valuable properties as a metal recovering and water purifying agent. Applications are waste water treatment for heavy metal and radio isotope removal and valuable metal recovery, potable water purification for reduction of unwanted metals, agriculture--controlled release of trace metals essential to plant growth, food--complex binding of iron in precooked food to reduce 'warmed-over flavour'. The interactions of metals with chitosan are complex, probably simultaneously dominated by adsorption, ion-exchange and chelation. To study this it is of utmost importance to work with well characterized chitosans. This has been a problem as available characterizing methodology is limited. Degree of polymerization and deacetylation and the distribution of acetyl groups along the polymer chain is of crucial importance for chitosan metal interacting characteristics. Making chemical derivatives is a way to alter the metal interacting characteristics of chitosan. Chitosan possesses general coagulant/flocculant characteristics towards bio-molecules and surfaces.

Effects of Phosphate in Combination with Nitrite or Maillard Reaction Products upon Warmed‐Over Flavor in Precooked, Restructured Beef Chuck Roasts

ABSTRACTThe effectiveness of a phosphate compound alone in combination with other antioxidants in preventing warmed‐over flavor (WOF) in precooked recombined beef roasts was investigated. Treatments without phosphate had significantly different proximate composition due to lower yields and higher cooking losses and received lower tenderness and juiciness scores from the sensory panel. WOF scores and thiobarbituric acid (TBA) values were lower (P &lt; 0.05) for the phosphate treatments. A correlation coefficient of 0.96 was obtained between panel scores and TBA numbers. The panel threshold for WOF was 1.6 TBA value. Results indicate phosphate alone was effective in preventing WOF in vacuum packaged precooked roast beef.