Loss Of Flavor Research Articles

SENSORY EVALUATION OF DRIED BEEF STRIPS TREATED WITH ACETIC ACID OR BRINE AND MONOSODIUM GLUTAMATE

ABSTRACT Loss of characteristic meat flavor in dried beef, because of biochemical degradation of flavor-enhancing nucleotides, raises concern over the taste of meat products made in the home. Preservation effects on beef taste, using acetic acid and brine followed by dehydration were studied. Monosodium glutamate was added to the dried strips prior to cooking. The beefsteaks were subjected to three treatments: acetic acid, brine, while the control was untreated fresh beef. The samples were cut into strips then dried in a solar drier and an oven. Sensory attributes were evaluated for tenderness, juiciness, color, flavor and overall acceptability by an untrained sensory panel. Acetic acid, brine and control treatments were significantly different (P < 0.05) from fresh beef in tenderness, juiciness and color. Cooked beef flavor comparisons indicated that brine was better (P < 0.05) than acetic acid. Addition of monosodium glutamate to dried products significantly (P < 0.05) improved cooked beef flavor and acceptability. PRACTICAL APPLICATIONS This is a low-cost method of meat preservation, and it is an appropriate technology that can be adopted in the arid and semi-arid areas of developing countries, because of its economic and nutritional implication. In these areas, meat production from small and large animals is the cornerstone of economic development and proper nutrition. These areas lack both refrigeration (the conventional method of meat preservation) and appropriate and affordable meat preservation technologies, making it impossible for the communities to utilize and market meat from their livestock profitably without sustaining high losses because of spoilage.

Protein and glycerol contents affect physico-chemical properties of soy protein isolate-based edible films

This study was conducted to determine the effect of both soy protein and glycerol contents on physico-chemical properties of soy protein isolate-based edible (SPI) films. The aim of this study was to better understand the influence of SPI and GLY contents on the behavior of the physico-chemical properties of soy protein isolate-based films. Films were casted from heated (70 °C for 20 min) alkaline (pH 10) aqueous solutions of SPI at 6, 7, 8, and 9 (w/w %), glycerol (50%, w/w, of SPI) and SPI at 7 (w/w %), glycerol (40, 60, 70 %, w/w of SPI). Water vapor permeability (WVP), was measured at 25 °C and for four different relative humidities (30–100%, 30–84%, 30–75%, 30–53%). Surface properties and differential scanning calorimetry were also measured. Varying the proportion of SPI and GLY had an effect on water vapor permeability, wetting and thermal properties of SPI films. A synergistic effect of glycerol and protein was observed on the water vapor permeability. Glycerol and RH gradient strongly enhance the moisture absorption rates and permeability of SPI based films. SPI content weakly increases the WVP and does not modify the surface properties. The temperature of denaturation of soy protein decreases glycerol content except for the higher concentration whereas it increases with protein ratio. This topic of research aims to control mass transfers within composite foods or betweenfoods and surrounding media (for instance the headspace in packagings). The targeted applications from this work deals with the food product coating or the coating of paper-based packaging for limiting both the loss of water and flavors by cheese based products. This will allow to maintain the weight of the cheese during “ripening” and commercialization, and also to prevent (off-) flavour dissemination from very odorant cheese as produced in France and Poland.

Encapsulation of aroma compounds in biopolymeric emulsion based edible films to control flavour release

Flavour loss strongly affects food quality. In order to decrease flavour changes during food conservation, different strategies could be used. Aroma compound encapsulation allows the protection of food flavour from loss and degradative reactions, like oxidation. Edible films could be an encapsulation matrix: in the case of emulsified film, lipid globules incorporated can act as carriers of active molecules, such as aroma compounds. Edible films prepared from ι-carrageenans are interesting for good mechanical and gas barrier properties. The aim of this study was to encapsulate different aroma compounds in an ι-carrageenan emulsion based edible film. Release of ten aroma compounds was compared to that obtained from a lipid matrix, Grindsted Barrier System 2000 (GBS), was also used as an edible film formulation. Flavour release was followed by HS-SPME measurements. This study allowed the influence of both matrix and aroma compounds characteristics on flavour release to be investigated. This study presents new understanding of the role of emulsion based edible films as a matrix able to encapsulate aroma compounds. Carrageenans films were possible encapsulating matrixes because they showed better performances for retention of more polar aroma compounds than the usual lipid supports. Carrageenans films were able to retain volatile compounds during film-process formation, and to release gradually with time.

HIGH PRESSURE PROCESSING INACTIVATION OFLISTERIA INNOCUAIN MINCED TROUT (ONCORHYNCHUS MYKISS)

ABSTRACT High pressure processing is a food pasteurization process with the potential to kill microorganisms with minimal effects on the sensory quality and nutrient content of the food. The effectiveness of HPP for inactivating Listeria innocua in a muscle food model system consisting of minced trout (Oncorhynchus mykiss) at different salt levels (0, 1, or 3% added NaCl), and the resultant visual changes to the mince using scanning electron microscopy (SEM) was examined. A three-strain cocktail of the pathogen surrogate L. innocua (ca. 108–109 cfu/g) was inoculated into fish samples, which were treated at eight pressures in the range of 150–517 MPa at 20C. Treatment at ≥414 MPa for 5 min achieved greater than a 4-log reduction for the Listeria strains tested. Adding salt increased the effectiveness of pressure treatment for the 414 MPa and 517 MPa treatments by an additional 2.5-log. SEM revealed evidence of cell wall deformation and collapse in pressure-treated samples, particularly at 414 and 517 MPa. This study indicates that HPP treatment could potentially be an effective nonthermal pasteurization method for certain types of cured fish products. PRACTICAL APPLICATIONS High pressure processing (HHP) was examined as an alternative to thermal post-packaging pasteurization for Listeria sp. control which often causes softening and loss of flavor and color in ready-to-eat cured and smoked aquatic foods. Adding salt to cured minced trout (1 or 3% by weight) increased the inactivation of Listeria sp. during HHP processing (150–517 MPa at 20C, 5 min). Four-log or higher reductions at or above 414 MPa were possible. Effective pasteurization processes resulted in toughening, but this may be desirable in formed fish products and jerkies made from fish such as trout, chum or pink salmon where the muscle tends to be soft. Pressure treatment may reduce the need for phosphate additives in minced fish yielding a “cleaner” (no additives) label statement. Improving texture during pasteurization could increase the utilization of muscle from frames and smaller fish in higher value food items.

PROCESS DEVELOPMENT AND OPTIMIZATION FOR FREEZE‐DRYING OF NATURAL ORANGE JUICE

ABSTRACT Freeze‐drying is a method of dehydrating frozen materials by a process of sublimation under vacuum, usually for the purpose of preservation. It is a procedure relatively expensive compared to other possible techniques; however, better results may be achieved when freeze‐drying is used, especially for thermally sensitive components. The performance of the freeze‐drying process is strongly dependent on the adequate operational conditions, and so it is necessary to have extensive analysis of effects of process variables mainly in terms of process time and quality of the obtained product. In the present work, a parametric sensitivity analysis based on the experimental data is presented and a suitable statistical procedure is applied. In order to obtain a product with the market requirements as well as with high productivity and lower costs, process improvement is necessary. Optimization through factorial design using response surface methodology was carried through extensive experimental study. In order to verify the product quality, infrared humidity and water activity were used and it was shown that the process performance might be significantly improved if optimal operating conditions were used. PRACTICAL APPLICATIONSThe stability, storage and distribution of certified reference materials, which may consist of liquid or frozen fruit juices, are rather problematic. A possible alternative solution to this problem is the storage and the transport in powdered form. Orange juice powder by freeze‐drying is a very interesting alternative to recompose the juice with practically all the properties of the natural product. Several specific applications may be visualized either to the food industry or to pharmaceutical use.Among others, a fundamental factor affecting the quality of the dried product when conventional procedures (as evaporation for instance) are used is the thermal damage during the concentration and drying steps leading to loss of flavor as well as of some vitamins and difficulty of redispersion. Because of the low temperatures involved and the highly porous structure formed, freeze‐drying is one of the processes that most minimize these effects.A process for the freeze‐drying of natural orange juice was developed. The best operational conditions were identified so that high performance is achieved both in terms of operation time and product quality.

Shelf Life of Packaged Bakery Goods—A Review

Packaging requirements for fresh bakery goods are often minimal as many of the products are for immediate consumption. However, packaging can be an important factor in extending the shelf life of other cereal-based goods (toast, frozen products, biscuits, cakes, pastas). Some amount of the texture changes and flavor loss manifest over the shelf life of a soft-baked good can usually be minimized or delayed by effective use of packaging materials. The gains in the extension of shelf life will be application specific. It is recognized that defining the shelf life of a food is a difficult task and is an area of intense research for food product development scientists (food technologists, microbiologists, packaging experts). Proper application of chemical kinetic principles to food quality loss allows for efficiently designing appropriate shelf-life tests and maximizing the useful information that can be obtained from the resulting data. In the development of any new food product including reformulating, change of packaging, or storage/distribution condition (to penetrate into a new market), one important aspect is the knowledge of shelf life.

Encapsulation Performance of Proteins and Traditional Materials for Spray Dried Flavors

The objective of this study was to evaluate the potential of selected proteins as alternative materials for flavor encapsulation by spray drying. Two traditional materials (gum acacia and modified starch) and three proteins (sodium caseinate, whey and soy protein isolates) were used at different infeed solid levels; test compounds included (R)-(+)-limonene and three alpha,beta-unsaturated aldehydes ((E)-2-hexenal, (E)-cinnamaldehyde, citral). The primary criteria for performance were flavor retention during drying and protection against losses during storage. Limonene oxidation and nonenzymatic browning were investigated as two possible deterioration routes. Overall, higher infeed solids improved retention during drying and limited flavor losses (aldehydes and limonene) during storage in traditional materials only. The materials giving the highest flavor retention during drying were gum acacia (94%), modified starch (88%) and whey protein isolate (87%). Gum acacia provided the highest retention of aldehydes during storage (37 to 58%) after 28 days at 40 degrees C but did not afford good protection against limonene oxidation. Oppositely, protein materials effectively limited limonene oxidation (>70% retained). Nonenzymatic browning was observed for all powders prepared with proteins, especially whey protein isolate, whereas no browning occurred with traditional materials.

Stability of Citral in Oil-in-Water Emulsions Prepared with Medium-Chain Triacylglycerols and Triacetin

Citral is widely used in the beverage, food, and fragrance industries for its characteristic flavor profile. However, it chemically degrades over time in aqueous solutions due to an acid-catalyzed reaction, which leads to loss of desirable flavor notes and formation of off-flavor notes. The objective of this research was to examine the impact of organic phase composition [triacetin and medium-chain triacylglycerols (MCT)] on the oil-water partitioning and chemical degradation of citral in oil-in-water emulsions. MCT was present as emulsion droplets (d approximately 900 nm), whereas triacetin was present as microemulsion droplets (d approximately 10 nm). In the absence of organic phase, the rate of citral degradation increased as the aqueous phase pH was reduced from 7 to 3. The percentage of citral within the aqueous phase increased with increasing triacetin concentration at both pH 3 and 7, which was attributed to a reduction in MCT droplet concentration. There was no significant change in the particle size distribution of the emulsions during storage, independent of triacetin concentration and pH, which indicated that they were physically stable. Both 5 wt % MCT as emulsion droplets and 5 wt % triacetin as microemulsion droplets were able to appreciably slow citral degradation at pH 3. These results may have important implications for understanding and improving the chemical stability of citral in beverage emulsions.

The degradation kinetics of flavor in black pepper ( Piper nigrum L.)

Kinetics of flavor degradation in black pepper was studied at isothermal (50–120 °C) and non-isothermal conditions. The degradation of flavor was also followed in three different cooking methods viz., open pan, pressure cooking and a newly developed slow cooker named “EcoCooker’. Flavor was evaluated in terms of piperine for pungency and total extractable oleoresin. The degradation of flavor (piperine and total extractable oleoresin) was found to follow first order kinetics. A mathematical model has been developed using the isothermal kinetic parameters obtained to predict the flavor loss from the time–temperature data of non-isothermal heating/processing method.

The aroma development during storage of Castlebrite apricots as evaluated by gas chromatography, electronic nose, and sensory analysis

One of the most important factors limiting apricot quality is the loss of flavor during storage, particularly overall aroma. To characterize fruit aroma, several techniques have been used, including both instrumental- and sensory-based methodologies. Despite the importance of aroma in fruit quality, limited information is available regarding the effects of long-term cold storage and ripening on the apricot’s volatile compound profile. The objective of this research was to characterize the aroma of two lots of Castlebrite apricots at different stages of initial maturity using gas chromatography–mass spectrometry (GC–MS), electronic nose (e-nose) analysis, and a sensory panel. GC measurements were performed on both intact fruit and ground fruit tissue. Evaluations were performed at harvest, after 15 or 30 d of cold storage at 0 °C under a normal air atmosphere and also after a simulated shelf-life period at 20 °C. Among the volatiles identified by GC–MS, aldehydes and esters were the primary constituents of Castlebrite apricot aroma, and differences in volatile aroma profiles were observed between intact and ground fruit. Only the concentrations of aldehyde compounds, primarily hexanal, were different between maturity stages. Furthermore, the e-nose was able to successfully differentiate between the two different stages of fruit maturity examined, but only after simulated shelf-life storage. Interestingly, despite the changes detected by GC and the e-nose, the sensory panel could not identify any differences between apricots at different stages of maturity.

Microwave processing of avocado: Volatile flavor profiling and olfactometry

Abstract The aim of this research was to evaluate the effect of microwave time, pH and avocado leaves on the volatile profile of avocado using response surface methodology, and aroma extract dilution analysis (AEDA) was employed to evaluate changes in the odorant composition. Response surface analyses showed maximum values for volatiles derived from lipid oxidation at high levels of microwave time and low values of pH. The presence of terpenoids, estragole, hexanal and 2-hexenal [ E ] was enhanced with the addition of avocado leaves. The optimum condition to prepare avocado puree was 30 s heating time, pH 5.5 and 1% of leaves. Comparative AEDA analysis for microwaved avocado puree added with and without avocado leaves showed changes in the FD of compounds derived from lipids. In addition, AEDA suggests that the addition of avocado leaves to microwaved avocado is related to the presence of important odorants such α-pinene, estragole and 2-hexenal [ E ]. Industrial relevance Several attempts have been made to process avocados as puree or “guacamole”. Microwave treatment offers an alternative for the blanching of fruits and vegetables, since the application of high temperatures for short times often results in minimum damage. Furthermore, previous studies have shown that better retention of color and lightness is obtained when avocado puree is processed in a microwave oven. However, a great loss of flavor takes place when this commodity is treated by heat. The application of a combined treatment consisting of microwaves, pH and the addition of avocado leaves to the puree minimizes flavor loss and results in a product with the characteristic flavor of avocado.

Accuracy of Self‐Report in Detecting Taste Dysfunction

To determine the sensitivity, specificity, and positive and negative predictive value of responses to the following questionnaire statements in detecting taste loss: "I can detect salt in chips, pretzels, or salted nuts," "I can detect sourness in vinegar, pickles, or lemon," "I can detect sweetness in soda, cookies, or ice cream," and "I can detect bitterness, in coffee, beer, or tonic water." Responses to an additional item, "I can detect chocolate in cocoa, cake or candy," was examined to determine whether patients clearly differentiate between taste loss and flavor loss secondary to olfactory dysfunction. A total of 469 patients (207 men, mean age = 54 years, standard deviation = 15 years; and 262 women, mean age = 54 years, standard deviation = 14 years) were administered a questionnaire containing these questions with the response categories of "easily," "somewhat," and "not at all," followed by a comprehensive taste and smell test battery. The questionnaire items poorly detected bona fide taste problems. However, they were sensitive in detecting persons without such problems (i.e., they exhibited low positive but high negative predictive value). Dysfunction categories of the University of Pennsylvania Smell Identification Test (UPSIT) were not meaningfully related to subjects' responses to the questionnaire statements. Both sex and age influenced performance on most of the taste tests, with older persons performing more poorly than younger ones and women typically outperforming men. Although it is commonly assumed that straight-forward questions concerning taste may be useful in detecting taste disorders, this study suggests this is not the case. However, patients who specifically report having no problems with taste perception usually do not exhibit taste dysfunction. The difficulty in detecting true taste problems by focused questionnaire items likely reflects a combination of factors. These include the relatively low prevalence of taste deficits in the general population and the tendency of patients to confuse loss of olfaction-related flavor sensations with taste-bud mediated deficits.

Electron microscopic analysis of dairy microbes inactivated by ultrasound

Ultrasonication is a non-thermal method of food preservation that has the advantage of inactivating microbes in food without causing the common side-effects associated with conventional heat treatments, such as nutrient and flavour loss. The aim of this study was to evaluate the use of ultrasound as an alternative to heat pasteurisation and to assess cell damage using transmission electron microscopy (TEM). Three spoilage microbes, previously isolated from pasteurised milk, were used as “test” microbes. Saline solution (SSS) and UHT milk were used as suspension media and were inoculated with exponential growth phase “test” microbes at a microbial concentration of 1 × 10 4 cfu ml −1. The samples were subjected to power ultrasound (20 kHz, 750 W), at 100%/124 μm wave amplitude for different time intervals. Both Escherichia coli and Saccharomyces cerevisiae were reduced by >99% (for both suspension media) after ultrasonication and Lactobacillus acidophilus was reduced by 72% and 84% in SSS and milk, respectively. Transmission electron microscope micrographs showed that ultrasonication inflicts extensive microbicidal/microbistatic external and internal damage on all three “test” microbes. In E. coli, sonication-induced emulsification caused the formation of unique minute lipopolysaccharide vesicles from the fragmenting cell envelope.

Flavour loss during postharvest handling and marketing of fresh-cut produce

Purpose of review: Loss of flavour of fresh-cut fruits and vegetables following postharvest handling, storage and marketing results in consumer dissatisfaction and often precedes the loss of visual quality. In order to maximise product flavour, causes of its loss must be identified and prevented. Therefore, this review assesses mechanisms and factors that affect flavour loss in fresh-cut produce. Findings: Flavour loss of fresh-cut fruits and vegetables can be attributed to metabolic changes of flavour compounds and diffusional loss of volatile compounds. The contribution of each of these mechanisms has not been clearly defined in any fresh-cut commodity. Fresh-cut processing stimulates flavour loss by removing natural diffusion barriers and altering normal metabolism. Packaging can alter metabolism of flavour compounds by altering atmosphere composition, which can inhibit flavour compound synthesis or induce the production of off-flavours. Polymer films used in packaging or edible coatings can also inhibit diffusional loss of volatile flavour compounds by serving as a barrier to prevent or stimulate loss by scalping compounds from the package atmosphere. Various postharvest chemical and physical treatments used to prevent browning, reduce microbial growth and maintain product quality may affect product flavour. Directions for future research: The contribution of metabolic and diffusional processes in determining flavour change of fresh-cut fruits and vegetables during postharvest handling and marketing needs to be determined for fresh products. Determination of the significance of these processes and how packaging and postharvest treatments can affect them could lead to new technologies to preserve flavour quality in fresh-cut produce.

Ethanol and aroma compounds transfer study for partial dealcoholization of wine using membrane contactor

In the present work viability of membrane contactors application to partial dealcoholize wines was checked using synthetic wine solutions. A hollow fiber polypropylene (PP) membrane contactor was employed. The process was performed at room temperature and using the most frequent component concentrations present in real wines. The influence of feed and stripping flow rates variation was analyzed. A model considering three resistances in series was developed to predict the ethanol and aroma compounds behavior inside the membrane contactor. Detailed study of the contribution of the individual resistances for ethanol showed that the major contribution to the transport resistance was due to membrane one. The membrane mass transfer coefficient can be calculated using Dusty-gas model expression obtaining a value of K m EtOH = 1.6 × 10 − 4 g P a − 1 m − 2 s − 1 . Flavor losses are higher when ethanol content reduction in feed phase increases. Aroma compound losses can reach almost 100% for the most volatile compounds when residence time of the feed stream is larger. A partial dealcoholization of 2% (v/v) gives as a result acceptable aroma losses that do not damage the final perceived quality of the product. A validation on a real wine was performed with an associated sensorial analysis.

Effect of refrigerated storage on ascorbic acid content of orange juice treated by pulsed electric fields and thermal pasteurization

Application of pulsed electric fields (PEF) can lead to longer shelf life of fruit juices with minimal product quality loss and good retention of fresh-like flavour. The aim of this study was to evaluate the effect of PEF and conventional pasteurization (90 °C, 20 s) on ascorbic acid content of orange juice, and to assess modifications in ascorbic acid concentration of orange juice stored in refrigeration at 2 and 10 °C for 7 weeks. The ascorbic acid degradation rate was −0.0003, −0.0006, −0.0009 and −0.0010 μs−1 for fields of 25, 30, 35 and 40 kV/cm, respectively. With selected PEF treatment (30 kV/cm and 100 μs) the shelf life based on 50% ascorbic acid losses was 277 days for the PEF-treated orange juice stored at 2 °C, while for the pasteurized juice was 90 days.

Mapping Fruit Susceptibility to Postharvest Physiological Disorders and Decay Using a Collection of Near-isogenic Lines of Melon

Melon (Cucumis melo L.) is a perishable fruit that requires refrigeration to extend its shelf life. Postharvest behavior differs substantially among melon varieties due to genetic differences. In this work, we use a collection of near-isogenic lines (NILs) derived from a cross between the Spanish cultivar Piel de Sapo (PS) and an exotic Korean accession ‘Shongwan Charmi’ [SC (PI161375)], each of them with a single introgressed region from SC into the PS background, to detect and map quantitative trait loci (QTLs) involved in postharvest life traits, such as total losses, water-soaking, necrosis of the placental tissue, chilling injury (CI), decay, fruit over-ripening, flesh browning, hollow flesh disorder, and flavor loss during storage. Fruit were examined at harvest and after 35 days at 8 °C. Three QTLs induced desirable quality traits: flv4.1 reduced the loss of fruit flavor after refrigeration, tl8.1 reduced total losses, and fus8.4 reduced the susceptibility to fusarium rot (Fusarium Link). Another 11 QTLs produced a detrimental effect on other quality traits. The NIL population was useful for dissecting complex, difficult-to-measure pre- and postharvest disorder traits of different degrees of development and for investigating flavor loss during storage. Further studies with the QTLs described herein will shed light on the genetic control of melon shelf life and help breeders who are interested in this fruit quality trait.

Effect of Cold Storage and Packaging Material on the Major Aroma Components of Sweet Cream Butter

The major aroma compounds of commercial sweet cream AA butter quarters were analyzed by GC-olfactometry and GC-MS combined with dynamic headspace analysis (DHA) and solvent-assisted flavor evaporation (SAFE). In addition, the effect of long-term storage (0, 6, and 12 months) and type of wrapping material (wax parchment paper vs foil) on the aroma components and sensory properties of these butters kept under refrigerated (4 degrees C) and frozen (-20 degrees C) storage was evaluated. The most intense compounds in the aroma of pasteurized AA butter were butanoic acid, delta-octalactone, delta-decalactone, 1-octen-3-one, 2-acetyl-1-pyrroline, dimethyl trisulfide, and diacetyl. The intensities of lipid oxidation volatiles and methyl ketones increased as a function of storage time. Refrigerated storage caused greater flavor deterioration compared with frozen storage. The intensity and relative abundance of styrene increased as a function of time of storage at refrigeration temperature. Butter kept frozen for 12 months exhibited lower styrene levels and a flavor profile more similar to that of fresh butter compared to butter refrigerated for 12 months. Foil wrapping material performed better than wax parchment paper in preventing styrene migration into butter and in minimizing the formation of lipid oxidation and hydroxyl acid products that contribute to the loss of fresh butter flavor.

Biochemical changes and antioxidant activity of mango ginger ( Curcuma amada Roxb.) rhizomes during postharvest storage at different temperatures

Mango ginger ( Curcuma amada Roxb.) is a unique species having mango flavour in its rhizomes and is of high medicinal importance. Its shelf-life and quality is governed by storage temperature and time. The present study pertains to biochemical changes and antioxidant activity in mango ginger rhizomes during storage. No significant changes were observed in pH, titrable acidity and TSS of the rhizomes stored at different temperatures, viz. room temperature (RT, 25 °C), low temperature (LT, 14 °C) and chilling temperature (CT, 4 °C). Total protein decreased initially from 11.2 to 7.9 mg/100 g rhizome up to 70 days, followed by a rapid increase to 10.6 mg on the 120th day of storage at RT. In contrast, total protein content increased at LT from 10 days onwards. The highest accumulation of total phenolic contents from 20.8 to 57.4 mg/100 g rhizome in juice and from 380 to 568 mg/100 g in pulp was observed in LT storage. The DPPH scavenging activity of mango ginger juice and pulp decreased sharply to 30 and 33%, respectively at RT, when compared with a steady activity of around 56% in juice and 72% in pulp at LT. Mango ginger rhizome could be stored for 4–5 months at LT compared with 2–3 months at RT. Shrivelling and sprouting are the limiting factors for further storage at RT, and the threshold percentage of water loss ranging from 30 to 36% was responsible for commercially objectionable levels of shrivelling. Within the range of temperatures, rhizomes exhibited chilling injury symptoms as water-soaked lesions with tissue softening, browning, loss of mango flavour and failure to sprout at the lowest temperature (CT), and rapid deterioration of physical, physiological and antioxidant properties at room temperature. Moderate low temperature (LT) minimized the biochemical changes, maintained or increased the antioxidant activity and doubled the shelf-life as a function of temperature with storage time.

Frozen storage stability of antioxidant-treated raw restructured beef steaks made from mature cows

Previous research has shown that beef quality decreased with the age of cattle. In this study, beef trimmings from nine mature cows ( n = 9), equally representing three animal age groups (2–4, 6–8, and 10–12 yr), were restructured into steaks formulated with propyl gallate, alone or in combination with a beefy flavoring agent, to enhance palatability and stability during 6 months of frozen storage at −29 °C. Lipid oxidation, rancidity, and loss of beefy flavor in restructured steaks during extended storage were reduced by propyl gallate. The beefy flavoring agent inclusion masked mature, forage-fed beef off-flavors, intensified beefy flavor, and improved steak tenderness, juiciness and cooking yield. Thus, the combination of propyl gallate and beefy flavoring offers an effective means to enhance the palatability and storage stability of restructured beef prepared from mature cows.