Sous-vide Method Research Articles

Effects of Different Marination Conditions on Quality, Microbiological Properties, and Sensory Characteristics of Pork Ham Cooked by the Sous-vide Method.

The aim of this study was to evaluate the effects of marinade under different conditions (temperature and vacuum) on pork ham cooked by the sous-vide method (61°C and 98.81% vacuum for 45 min). Control group was non-marinade pork ham. The samples were marinated under 1 of 4 conditions: 4°C, 98.81% vacuum (treatment group T1); 4°C, atmospheric pressure (T2); 20°C, 98.81% vacuum (T3); and 20°C, atmospheric pressure (T4). The pH value was higher in the control (6.02) than in the treatment groups (4.30–4.42, p<0.001). Shear force was the lowest in the control: 18.14 N. Lightness and redness values were higher in the control (p<0.001). The chroma value significantly decreased from 12.74 to 7.55 with marinade (p<0.001). Total viable and coliform counts of raw meat were 84.6 and 3.67 Log CFU/g, respectively. After the marinade, the total viable count decreased to 3.00–14.67 Log CFU/g (p<0.001). Coliforms were not detected. After sous-vide cooking, no viable microorganisms were detected in any group. Treatment groups generally showed high scores on consumer preference. The marinade and sous-vide cooking had a positive effect on sensory characteristics. They provided safe conditions for sanitary evaluation. As a result, it appears that marinade at refrigeration temperature is better than that at room temperature.

Effects of sous-vide method at different temperatures, times and vacuum degrees on the quality, structural, and microbiological properties of pork ham

This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber.

In vitro digestibility, free and bound phenolic profiles and antioxidant activity of thermally treated Eragrostis tef L.

Total phenolic content, phenolic profile and antioxidant activity were determined in free and bound phenolic fractions of thermally treated brown and white teff grains. Phenolic content in raw brown and white teff (1540 and 992 mg gallic acid equivalent kg-1 ) as well as antioxidant activity (6.3 and 5.5 mmol trolox equivalent kg-1 ) were higher in free phenolic fractions. The most significant decrease in total phenolics was observed after application of the sous-vide method (35% for brown teff and 11% for white teff). Main free phenolics of heat-treated teff were ferulic, protocatechuic, p-coumaric and ellagic acids, rutin and epigallocatechin. Main bound phenolics were ferulic, gallic, sinapic and ellagic acids, catechin and epigallocatechin. The detrimental effect on free and bound quercetin and bound cinnamic acid concentrations was also examined during heat treatment. Thermally treated brown teff showed a high level of in vitro organic matter digestibility if water cooking and rice cooker (both 99.5%) and sous-vide (96.5%) methods were applied. The sous-vide method may be recommended as the most suitable hydrothermal treatment for grains of teff when compared with water cooking and rice cooker methods. © 2017 Society of Chemical Industry.

Comparison of antioxidative properties of raw vegetables and thermally processed ones using the conventional and sous-vide methods

The study determines the antioxidant properties of methanol vegetable extracts from raw vegetables, conventionally cooked vegetables and sous-vide. In the research, two methods were used: free radical scavenging DPPH (µM Trolox) and the reduction of Fe3+to Fe2+ – FRAP (µM Fe2+). Antioxidative properties for raw vegetables were obtained with the range of 7.47–235 (µM Trolox/100g of vegetables) and 2.66–103 (µM Fe2+/100g of vegetables), for vegetables after the conventional cooking process 6.15–657 (µM Trolox/100g of vegetables) and 3.03–99.9 (µM Fe2+/100g of vegetables), for vegetables after the sous-vide process 4.45–648 (µM Trolox/100g of vegetables) and 3.06–99.9 (µM Fe2+/100g of vegetables). For some vegetables, an increase in the antioxidative potential was observed as a result of cooking processes; however, it was much higher for the sous-vide technique. All results were subjected to a one-way analysis of variance (ANOVA) and, if significant differences were revealed, the POST-HOC Duncan test was used (α=0.05).

Effects of different cooking methods on the chemical and physical properties of carrots and green peas

Abstract The study was aimed to evaluate the physicochemical effects of three cooking methods i.e. sous-vide (SV), cook-vide (CV) and traditional cooking (TC) on carrots and green peas. SV and CV were performed at 60–90 °C for various time periods (SV: green peas 50–100 min, carrots 90–150 min; CV: green peas 30–70 min, carrots 20–60 min) with respect to peroxidase test. These vegetables were also cooked at atmospheric pressure for 15, 30, 45 and 60 min and the results were compared with those obtained from SV and CV. Antioxidant activity, total phenolic and vitamin C analyses reflected less harm to the green peas in CV as compared to SV and TC. However, carrots were approximately half degraded during SV than in CV and TC as shown by the antioxidant activity. Moreover, total phenolic content of carrots was highly protected when cooked in SV method. The color change values (∆ E) of green peas were slightly lower in TC when compared to CV and SV, while in carrots, they were very close to each other's in all three methods. CV-cooked green peas and carrots provided the highest general acceptance for the sensorial properties. As a conclusion, TC had more adverse effects on the quality characteristics on green peas and carrots.

Analysis of the effects of thermal protein denaturation on the quality attributes of sous-vide cooked tuna

Traditional (low temperature, long time) and novel (low temperature, short time) sous-vide cooking of lean tuna were characterized by analyzing the effects of thermal protein denaturation (TPD) on quality attributes, such as color, appearance, shrinkage, drip loss, and texture. TPD was analyzed by differential scanning calorimetry and estimated for several thermal schedules by kinetic analysis, following the dynamic method. When heated at a rate of 10 °C/min, myosin began to denature at around 35 °C. Actin did not denature, even when the temperature rose to approximately 51 °C, until the denaturation of myosin was complete. However, actin began to denature at approximately 58 °C and was completely denatured at 76 °C. Actin denaturation had a stronger effect than myosin denaturation on texture changes, whereas myosin denaturation was responsible for changes in color and appearance. A better preservation of tuna quality was obtained by novel sous-vide cooking over the traditional sous-vide method. Practical applications The results of this study are useful to both the research community and industry because they provide quantitative characterization of the consequences of sous-vide cooking method on food quality explained by estimating TPD. Moreover, the kinetic parameters of the denaturation rate collected for kinetic modeling of the TPD of tuna, not only have application to simulate denaturation of actin and myosin under different thermal schedules of sous-vide cooking, but also they can be used for the analysis of additional thermal treatments.

Comparison of Sous-vide methods and traditional hydrothermal treatment on GLS content in Brassica vegetables

Brassica vegetables are a source of many biologically active compounds, including glucosinolates (GLS). At present, GLS attract a special attention because of their healthy properties. Four Brassica vegetables: cauliflower, Romanesco-type cauliflower, Brussels sprouts, and broccoli were examined. Analyses of GLS were done in raw, sous-vide cooked, traditionally cooked, and steamed vegetables as well as in samples stored for 5 days at 2 ± 1 °C. In the examined vegetables, 9 GLS were identified. The content of vitamin C was also determined. Moreover, microbiological analyses were performed. Among the investigated vegetables, the highest content of GLS was observed in the steamed samples. The traditional cooking of broccoli and Romanesco-type cauliflower causes a significant decrease of GLS as compared to the raw materials. The same explicit tendency was also observed in the case of cooking by the sous-vide method of Romanesco-type cauliflower and Brussels sprouts. Brussels sprouts, cooked by the sous-vide method, contained almost 40% less GLS than those cooked in water. Storage of the treated vegetables at 2 ± 1 °C led to a further reduction of the GLS level. It must be emphasized that the highest losses were observed in broccoli after sous-vide cooking (over 30%). Our results indicate that sous-vide method can be an advantageous technique of processing broccoli destined only for direct consumption.

Examining the safety of duck breast prepared the sous vide method

&#x0D; Objectives: There is an increasing desire in the culinary industry to use sous vide to prepare meals at low internal temperatures to enhance flavour, texture, and quality. The sous vide method uses specific time and temperature combinations to allow for sufficient microbial destruction. The BCCDC’s Guidelines for Restaurant Sous Vide Cooking Safety in British Columbia suggests time and temperature combinations to help ensure that the required log10 reductions of pathogens are achieved. Concerns for public safety arise when chefs deviate from the guidelines, and therefore may not achieve the appropriate log10 reductions. This study looked at a commonly used sous vide duck breast recipe and determine whether appropriate the appropriate log10 reductions were met. It also examine the efficacy of the sear step and resting period in achieving the log10 reductions. Methods: After calibration, two batches of 15 duck breasts were prepared using the sous vide method for 80 minutes at 58ºC, the breasts were then seared on a 200°C frying pan for 2 minutes each side, and then subjected to a 4 minute rest period at room temperature. The internal temperature of the breasts was continuously measured using SmartButton thermometers. This data was entered into the AMI Process Lethality Determination Spreadsheet to calculate the log10 reductions. The log10 reductions were analyzed using a one-sample t-test to assess whether the recipe achieved the required 7.0 log10 reductions. Results: The results showed 14% of the 29 duck breasts achieved a 7.0 log10 reduction after the sous vide step of 80 minutes at 58 ºC. The null hypothesis (Ho: measured log10 reductions of duck breasts = 7.0 log10 reductions) was rejected with 100% power and a p-value of 0.00. The mean was 5.13, therefore it seems as though the log10 reductions were significantly lower than 7.0 log10 reductions. After the sear and the resting period, 52% of 27 duck breasts achieved a 7.0 log10 reduction. Statistical analyses showed that the null hypothesis could not be rejected. The p-value was 0.97 and the power was 0.413. Disregarding cumulative effects, the median log10 reductions achieved only by the sear step was 0.43, and the median log10 reductions achieved solely by the resting period was 0.35. Conclusion: Due to lack of normality one cannot confidently say this recipe will achieve 7.0 log10 reductions. However, due to the high log10 reductions achieved, it seems plausible for another recipe to provide adequate log10 reductions while maintaining acceptable quality. The sous vide step should be used for the majority of the log10 reductions. Due to a wide variability in the results, the sear and resting period should only be used for small increases in log10 reductions.&#x0D;

Shelf Life of Chicken Meat Balls Submitted to Sous Vide Treatment

The objective of this study was to investigate the appropriate temperature for processing storage of chicken meatballs made of minced chicken meat with the sous vide method. The chicken meatballs were prepared and separated into four experimental groups according to the application of heat treatment (10 and 20 minutes) and storage time (+2 and +10°C). Sensory, microbiological (total aerobic mesophilic bacteria, total psychrotrophs, lactic acidbacteria, Enterobacteriaceae, Clostridiumperfringens, Listeria spp.), chemical (pH, thiobarbituric acid), color (L*, a*, b* values), and texture profile analyses were performed on meatball samples. Cl. perfringens and Listeria spp. were not detected in meatball samples during the storage period. Samples cooked at 10 minute and stored at +2°C the highest count of total aerobic mesophilic bacteria (p<0.05). For lipid oxidation, interaction was observed between cooking time and storage temperature, with higher TBARs values for samples stored at 10 °C, while cooking time and storage temperature showed no influence on the color and textural analysis parameters. For the treatments evaluated, cooking time x storage temperature seem affect more microbiological and chemical parameters than color and textural parameters of chicken meatballs.

Growth of Clostridium perfringens spores inoculated in sous-vide processed Korean traditional Galbijjim under different storage conditions

To evaluate the microbiological safety of Korean traditional seasoned beef processed by sous-vide method, Clostridium perfringens spores were inoculated into the samples, and then germination and growth of spores were observed under different temperatures for days. Also, changes in pH, water activity, and salt contents were analyzed. As the results, there was no difference in water activity and pH of the samples during the storage at any temperature. However, salt contents of the samples significantly increased as storage time increased, and the storage temperature affected the change of salt contents. C. perfringens did not grow at 4 and 10°C for 24 days however, the bacterial growth was observed at 20°C after 2 days of storage. Based on these simulation tests, the microbiological safety of sous-vide processed galbijjim can be guaranteed at 4 and 10°C for 24 days even though the raw materials were contaminated by C. perfringens spores.

Using Numerical Analysis to Develop and Evaluate the Method of High Temperature Sous‐Vide to Soften Carrot Texture in Different‐Sized Packages

The high-temperature sous-vide (HTSV) method was developed to prepare carrots with a soft texture at the appropriate degree of pasteurization. The effect of heating conditions, such as temperature and time, was investigated on various package sizes. Heating temperatures of 70, 80, and 90 °C and heating times of 10 and 20 min were used to evaluate the HTSV method. A 3-dimensional conduction model and numerical simulations were used to estimate the temperature distribution and the rate of heat transfer to samples with various geometries. Four different-sized packages were prepared by stacking carrot sticks of identical size (9.6 × 9.6 × 90 mm) in a row. The sizes of the packages used were as follows: (1) 9.6 × 86.4 × 90, (2) 19.2 × 163.2 × 90, (3) 28.8 × 86.4 × 90, and (4) 38.4 × 86.4 × 90 mm. Although only a moderate change in color (L*, a*, and b*) was observed following HTSV cooking, there was a significant decrease in carrot hardness. The geometry of the package and the heating conditions significantly influenced the degree of pasteurization and the final texture of the carrots. Numerical simulations successfully described the effect of geometry on samples at different heating conditions.

A Novel Time/Temperature Approach to Sous Vide Cooking of Beef Muscle

Sous vide treatment is encountering a renewed interest among chefs and catering operators, but an important concern is that they had been joined by those who were not aware resulting in foods held at time/temperature combination that may be not appropriate by a qualitative point of view. In this study, beef semitendinosus muscles were sous vide cooked by applying two different time/temperature treatments, a typical low temperature–long time (LT-LT) condition realized by cooking 36 h at 75 °C (SV75) and an innovative high temperature–short time (HT-ST) one for 2 h at 100 °C (SV100). Data were compared to traditionally boiled meat, and changes in pasteurization values, weight loss, texture, color, vitamins of B group as well as volatile compounds profile were evaluated. HT-ST treatment proved to achieve a pasteurization value sufficient to exclude Clostridium perfringens risk, while on the contrary, LT-LT may be a sous vide cooking approach that could be subjected to this microbiological hazard. Total weight loss of SV100 resulted significantly lower compared to SV75. SV75 samples showed the lowest shear force and hardness, being also less red than the other two samples. In addition, vitamin B3 retention was very similar for both sous vide methods, while LT-LT condition allowed a higher retention of B12. Finally, volatile compounds of beef muscles cooked by means of LT-LT and HT-ST sous vide conditions showed lower accumulation of off-flavor such as hexanal or 3-octanone in comparison to traditional boiling technique and better preserved the volatile profile of raw meat. Sous vide cooking at HT-ST condition used in this study could represent a feasible alternative to low-temperature treatment allowing to obtain comparable or better qualitative standards except for vitamin B12 retention and hardness.

조리 온도와 조리 방법에 따른 돼지고기 뒷다리살의 물리 화학적 및 관능적 품질차이 비교연구

Quality changes of cooked meat products are dependent upon cooking temperature and heating methods. Pork ham is the most preferred pork dish using pork hams in South Korea although it is not suited to various cooking methods because its low fat content does not provide desirable physiochemical and sensory properties to consumers. Therefore, the objective of this study was to evaluate the effect of four different cooking methods on pork legs by comparing Ocoo, Sous-vide, steaming, and boiling technique at <TEX>$80^{\circ}C$</TEX> and <TEX>$100^{\circ}C$</TEX>. Ultimately, the most effective cooking method and temperature to improve the quality of cooked pork hams was investigated. As the results of texture analysis, the samples cooked using Ocoo and Sous-vide methods showed higher springiness and cohesiveness than those using steaming and boiling methods. For the sensory evaluation, participants liked the hardness, juiciness, chewiness, tenderness of the samples using the OC method, resulting in the highest overall acceptance rate. The results of this study showed that using Ocoo or Sous-Vide cooking methods can improve the quality of cooked pork hams in both physicochemical and sensory properties.

Evaluation of the Microbiological, Chemical and Sensory Quality of Carp Processed by the Sous Vide Method

This study evaluated the microbiological quality and the sensory characteristics of carp fillets processed by the sousvide method when stored at 2 and 10 °C. Four different combinations of sauced–storage were studied then stored at 2 or 10 °C was evaluate periodically sensory, microbiological and chemical quality. Batches stored at 2 °C had lower growth rates of mesophiles and psychrotrophs. Moreover, these counts decreased by increasing the heating temperature and time. Staphylococcus aureus, Bacillus cereus, Clostridium perfringens and Listeria monocytogenes were not found in any of the samples. The heat treatment of 90 °C for 15 min and sauced was the most effective to ensure the safety and extend the shelf-life of sousvide carp preserving its sensory characteristics. This study establishes the microbiological quality of sous vide carp and emphasizes the relevance of the raw materials, heat treatment and storage temperature to ensure the safety of the product. Keywords—Sousvide methods, carp, sauce, microbiological, chemical and sensory quality

Microbial, physical–chemical and sensory spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method

The aim was to study spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method. Samples were packaged under vacuum into polyamide-polypropylene pouches, cooked at an oven temperature/time of 70°C/12h, chilled at 3°C and stored at 2°C for 0, 5 or 10 weeks. Microbial (psychrotrophs, lactic acid bacteria, Enterobacteriaceae, moulds and yeasts), physical–chemical (pH, water activity, TBARS, acidity, L∗a∗b∗ colour, texture profile analysis and shear force) and sensory (appearance, odour, flavour, texture and acceptance) parameters were determined. The results showed that sensory spoilage preceded microbiological spoilage of sous vide pork loin. Counts bellow 1logcfu/g of psychrotrophs, anaerobic psychrotrophs, Enterobacteriaceae and lactic acid bacteria were detected in any control week, while moderate counts (2–3logcfu/g) of moulds and yeasts were found. Minor changes in water activity, lipid oxidation, CIELab colour, hardness, cohesiveness or gumminess were associated with spoilage of pork loin, only decreases of lactic acid, springiness and shear force were observed. The pork loin was unacceptable after 10 weeks. This loss of acceptance was mainly due to the deterioration of meaty flavour and odour, although the loss of appearance, juiciness and firmness also contributed. Moderate warmed-over and rancidity were detected. The sensory analysis was the most effective method for determining the shelf life of the sous vide pork-based dishes.

Textural properties of potatoes (Solanum tuberosum L., cv. Monalisa) as affected by different cooking processes

Abstract The use of vacuum for the cooking of food is one of the techniques that has been developed in the field of haute cuisine over the last 10 years. Despite this, very little research work has been undertaken which analyses the changes that these procedures can make to the product. In this paper, the effect of the use of continuous vacuum cooking, the sous-vide method and the atmospheric pressure cooking treatment on textural changes in the potato (cv. Monalisa) were studied. To do this, potato cylinders were cooked using the previously mentioned procedures at temperatures of 60, 70, 80 and 90 °C for time periods which ranged between 5 and 60 min. The samples obtained were evaluated by texture profile analysis (TPA) and the microstructure by the Cryo-SEM. TPA parameters, such as hardness, chewiness, cohesiveness and adhesiveness values, were affected by temperature and treatment duration.

Development of a sous-vide packaging process for Korean seasoned beef

From an analysis of the conventional process for cooking Korean seasoned beef, a sous-vide processing method was developed that offers convenience and storage stability. The new process consists of boiling, simmering and slicing the meat slab, evaporative concentration of boiled beef brine and soy sauce, filling a gas-barrier film pouch with the beef slices and concentrated brine with spice ingredients, and pasteurising the sealed package. The sous-vide packaging resulted in better sensory quality and storage stability compared with the conventional method. The shelf life based on the sensory quality change was around 12 days when stored at 3 and 10 °C for the products processed by the sous-vide method, whereas it was 7 and 3 days, respectively, for the conventionally processed products. The sous-vide packaging was effective in protecting the product from microbial, physical, and sensory quality degradation.

Evaluation of the microbiological safety and sensory quality of rainbow trout ( Oncorhynchus mykiss) processed by the sous vide method

This work evaluates the microbiological quality and sensorial characteristics of rainbow trout processed by the sous vide method under different time/temperature conditions and stored at 2°C and 10°C. The equivalent heat treatments applied in core were: 3.3 min at 90°C (PV 70 in core 331.64), 1.04 min at 90°C (PV 70 in core 104.5) and 5.18 min at 70°C (PV 70 in core 5.18). The product stored at 2°C or 10°C was periodically evaluated to investigate its sensory quality, microbiological condition and proximate composition. The batches stored at 2°C had lower growth counts of mesophiles and psychrotrophs. Moreover, these counts decreased by increasing the heating temperature and time. Staphylococcus aureus, Bacillus cereus, Clostridium perfringens and Listeria monocytogenes were not found in any of the samples. Neither aerobic nor anaerobic spores were detected in the trout samples processed at 90°C for 3.3 min in core and stored at 2°C after 45 days. A heat treatment of 90°C for 3.3 min in core was the most effective to extend the shelf-life of trout (>45 days). Therefore, it can be concluded that the treatment at 90°C for 3.3 min in core is the most effective to ensure the safety and extend the shelf-life of sous vide trout preserving its sensory characteristics. This study establishes the microbiological quality of sous vide trout and emphasizes the relevance of the microbiological quality of the raw materials, heat treatment and storage temperature to ensure the safety of the product, since this fatty fish is not eviscerated and high counts can be found in the raw fish.

Microbiological safety and sensory characteristics of salmon slices processed by the sous vide method

Abstract The aim of this work is to evaluated the microbiological quality and the sensory characteristics of salmon slices processed by the sous vide method under different conditions of time–temperature when stored at 2 and 10 °C. Three different combinations of time–temperature were studied (5 min/65 °C, 10 min/90 °C and 15 min/90 °C). The product stored at 2 or 10 °C was evaluated periodically to study its sensory quality, microbiological condition and proximate composition. Batches stored at 2 °C had lower growth rates of mesophiles and psychrotrophs. Staphylococcus aureus , Bacillus cereus , Clostridium perfringens and Listeria monocytogenes were not found in any of the samples. Neither aerobic nor anaerobic sporeforming bacteria were detected in the salmon processed at 90 °C for 15 min and stored at 2 °C after 45 days. The heat treatment of 90 °C for 15 min was the most effective for extending the shelf life of fish (>45 days). However, under these conditions the sensory characteristics were not optimal. It can be conclude that the treatment at 90 °C for 15 min was the most effective one to ensure the safety and to extend the shelf life of sous vide salmon. However, under these conditions the sensory characteristics were not optimal immediately after processing. This study emphasizes the importance of heat treatment and storage temperature in order to ensure the safety particularly in a fat fish, since fat can acts as a protecting agent in the heat resistance of microorganisms.

Sous vide processing of seasoned spinach soup

Spinach soup seasoned with fermented soybean paste, red pepper paste and other minor ingredients was processed into 600 g plastic pouch package by the sous vide method. The process involved hot filling, pasteurization based on the inactivation of psychrotropic Clostridium botulinum, and rapid chilling. The processed products were stored at 3 and 10°C with periodic sampling for quality measurements. The seasoned spinach soup processed by the sous vide method exhibited a sensory quality comparable to that of fresh soup. The pasteurized product showed a high microbial load of total aerobic bacterial count greater than 5 log CFU/g in the soup brine and 2 log CFU/g in the vegetable solids, caused by the use of fermented soybean and red pepper pastes in the seasoned brine. However, coliform bacteria, lactic acid bacteria and yeasts/moulds were not detected in the product. The product was stable in microbial quality during storage for 35 days at 3°C, while it was so only up to 10 days at 10°C. The surface colour, total chlorophyll, ascorbic acid content and texture of the spinach in the soup showed gradual changes toward less green colour, lower nutrient retention and softer vegetables with their changes being faster at higher temperature. The seasoned spinach soup may be stored for appropriate time periods under chilled conditions and used in the food service industry with good quality characteristics.