DETERMINATION OF THE QUALITY AND SHELF LIFE OF SOUS VIDE PACKAGED BONITO (SARDA SARDA,BLOCH, 1793) STORED AT 4 AND 12C

ABSTRACT

The aim of this study was to determine the quality and shelf life of sous vide bonito stored at 4 and 12C. The total volatile basic nitrogen (TVB‐N) values of cold stored samples exceeded the recommended limit on 35th day of storage, while they were unacceptable according to sensory scores. The TVB‐N and trimethylamine‐N values of sous vide samples stored at 12C exceeded the limits at the 18th day, while sensory scores were very close to the acceptability limit. For all samples, mesophilic and psychrophilic bacterial counts exceeded the limits after they were regarded as spoiled. Therefore, the shelf life of the sous vide bonito, cooked at 70C for 10 min, was 28 days at 4C while 15 days at 12C. It was seen that sous vide packaging provided a long shelf life for bonito.

PRACTICAL APPLICATIONS

Sous vide is a long established but relatively little known cooking process. The data regarding the effect of storage temperature on shelf life and quality of sous vide fish are very limited. Therefore, this study aimed to determine the sensory, microbiological and chemical quality of sous vides packaged bonito during refrigerated storage (4 ± 1C) and abuse temperature conditions (12 ± 1C). The results of this study can be utilized by researchers in future studies as well as by manufacturers to determine the processing and storage conditions of sous vide fish.     

Sous vide cooked beef muscles: effects of low temperature–long time (LT–LT) treatments on their quality characteristics and storage stability

Beef muscles were sous vide cooked by applying different low temperature-long time treatments and changes in their physical properties were measured. The effects of selected treatments on pasteurization values and chilled storage stability were investigated. The results obtained indicated that cooking weight loss increased and shear force values decreased as the treatment temperature was raised from 50 to 65 °C, while processing times (90–360 min) did not have a significant effect on these variables. The colour parameter a was strongly affected by the different treatments. The pasteurization values obtained were enough to inactivate vegetative cells but were insufficient to achieve a significant reduction of Clostridium botulinum spores. The microbial quality of the product remained acceptable during the storage period. Over the storage time, thiobarbituric acid reactive substance (TBARS) numbers were significantly affected by the thermal treatment applied. Maximum TBARS values obtained were lower than those reported for meat processed without vacuum. Cooked beef flavours for all treatments decreased uniformly after 21 days of storage.     

Effects of cooking methods on the proximate,mineral and fatty acid composition of European eel (Anguilla anguilla)

The influence of microwave cooking and traditional cooking methods such as baking, grilling and frying on the nutritional composition of eels (Anguilla anguilla) was studied. All methods reduced moisture and increased the protein and fat content. Although the potassium and sodium content of fish cooked by different methods decreased significantly (P = 0.000), the calcium and magnesium content increased. The zinc content of the fish was not affected by cooking. The manganese and iron content significantly increased only in fried fish. The copper content was increased by grilling and microwave cooking. The proportion of saturated fatty acids and monounsaturated fatty acids in cooked fish decreased. Omega‐3 polyunsaturated fatty acids were increased by all cooking methods. The grilling and microwave‐cooking methods were the most suitable considering the n3/n6 ratio and eicosapentaenoic acid levels. The increase in the docosahexaenoic acid level of fried fish enhanced its nutritional value.     

Physico‐Chemical and Structural Characteristics of Vegetables Cooked Under Sous‐Vide,Cook‐Vide,and Conventional Boiling

In this paper, physico‐chemical and structural properties of cut and cooked purple‐flesh potato, green bean pods, and carrots have been studied. Three different cooking methods have been applied: traditional cooking (boiling water at 100 °C), cook‐vide (at 80 and 90 °C) and sous‐vide (at 80 °C and 90 °C). Similar firmness was obtained in potato applying the same cooking time using traditional cooking (100 °C), and cook‐vide and sous‐vide at 90 °C, while in green beans and carrots the application of the sous‐vide (90 °C) required longer cooking times than cook‐vide (90 °C) and traditional cooking (100 °C). Losses in anthocyanins (for purple‐flesh potatoes) and ascorbic acid (for green beans) were higher applying traditional cooking. β‐Carotene extraction increased in carrots with traditional cooking and cook‐vide (P < 0.05). Cryo‐SEM micrographs suggested higher swelling pressure of starch in potatoes cells cooked in contact with water, such as traditional cooking and cook‐vide. Traditional cooking was the most aggressive treatment in green beans because the secondary walls were reduced compared with sous‐vide and cook‐vide. Sous‐vide preserved organelles in the carrot cells, which could explain the lower extraction of β‐carotene compared with cook‐vide and traditional cooking. Sous‐vide cooking of purple‐flesh potato is recommended to maintain its high anthocyanin content. Traditional boiling could be recommended for carrots because increase β‐carotenes availability. For green beans, cook‐vide, and sous‐vide provided products with higher ascorbic acid content.     

Development of a Hamburger Patty with Healthier Lipid Formulation and Study of its Nutritional, Sensory, and Stability Properties

A modified beef hamburger patty enriched in polyunsaturated n−3 fatty acids and α-tocopherol was developed using technological procedures. Raw meat was obtained from low-cost parts of beef carcasses (brisket and flank) to which visible fat and connective tissue was manually eliminated and substituted by a mixture of pre-emulsified olive, corn, and deodorized fish oil. The developed product was analyzed and compared to conventional beef hamburger patties for their proximate composition, fatty acid profile, and consumer acceptability. The effects of cooking on the fat content and fatty acid profile of the developed product were investigated. Additionally, the lipid oxidation and surface color stability of modified and conventional hamburgers were investigated during 8 days of refrigerated storage while packaged in a modified atmosphere (20%/80% CO₂/O₂) and subsequently cooking. The developed product showed significantly lower total fat, cholesterol, sodium, and calorie content than beef hamburger patties manufactured using conventional procedures. In addition, the polyunsaturated fatty acids/saturated fatty acids and n−6/n−3 ratios matched nutritional recommendations more closely. No evidence of lipid oxidation was found for the modified hamburger patties during 8-day storage period, and surface color, especially redness, was more stable than in conventional ones. Additionally, consumer acceptability of the developed patty after it was cooked was acceptable and similar to that of conventional products. The modified hamburger patty developed by technological methods is viable and can be considered a useful food to preclude nutritional disorders or to assist in nutritional regimens.     

脂肪添加种类和比例对鱼豆腐品质特性的影响

为研究脂肪添加种类和比例对鱼豆腐品质特性的影响,分别制备添加10%、20%、30%的乳化猪背膘 （emulsified pig backfat,EPB）或乳化鸡皮（emulsified chicken skin,ECS）的6 组鱼豆腐,并测定其营养成分、色 泽、蒸煮损失、质构特性、脂肪酸组成及横向弛豫时间（T2）。结果表明：随着脂肪添加比例的增加,鱼豆腐中的 蛋白质和水分含量明显降低,脂肪含量、脂肪酸总量、亮度值（L*）和白度值（W）有升高趋势;添加30%脂肪鱼 豆腐的蒸煮损失率最大,弹性和T22峰值最低;与添加ECS的鱼豆腐相比,添加EPB鱼豆腐的脂肪含量、L*、W、T22 较高,而蛋白质含量、水分含量、蒸煮损失率及不饱和脂肪酸含量较低。从营养特性、脂肪酸组成、蒸煮损失率、 色泽和凝胶特性等各项指标综合分析,在鱼豆腐的实际生产中,添加20%的脂肪比较合适,将EPB和ECS混合添加 的效果更好,不仅能有效改善鱼豆腐的脂肪酸及营养组成,得到的鱼豆腐成品口感和色泽俱佳,且成品具有较好的 质构特性。     

Effects of Four Cooking Methods on the Proximate, Mineral and Fatty Acid Composition of Fish Fillets

The effects of baking, broiling, deep frying and cooking in a microwave oven on the proximate, mineral and fatty acid composition of grouper (Epinephelus morio), red snapper (Lutjanus campechanus), Florida pompano (Trachinotus carolinus) and Spanish mackerel (Scomberomorus maculatus) were determined. The lipid content of low fat species was not significantly changed by cooking, but lipid was lost from fatty fillets during cooking. The fatty acid composition of all fillets was not significantly changed by baking, broiling or microwave cooking. Deep fried fillets absorbed the major fatty acids in the cooking medium, and as the fillet lipid content increased the extent of absorption of fatty acids from the cooking medium decreased. Sodium, potassium and magnesium levels were decreased when low fat species were cooked, but these minerals were not lost when raw fillets containing higher lipid levels were cooked. Cooking did not significantly affect the concentration of the microelements, zinc, copper, iron and manganese.     

Effects of modified atmosphere packing over the shelf life of sous vide from captive pirarucu (Arapaima gigas)

The goal of this study was to evaluate the effects of modified atmosphere in packing sous vide of pirarucu in tucupi and shrimp sauce under refrigeration. Three treatments were carried out vacuum at 98%, 60%CO₂/40%N₂, and 70%CO₂/30%N₂. The composition of CO₂ and N₂ was monitored along with evaluation of pH, a_w, water retention capacity, acidity, texture, N-TVB and TBARS, color, mesophilic and psychotropic anaerobes, presence of Salmonella spp, sulphite-reducing Clostridia, counts of coagulase-positive Staphylococci, coliforms at 45 °C and sensorial analysis. All results were compared through ANOVA, Tukey's test, Principal Component Analysis and Multiple Factor Analysis. We observed a trend towards the reduction of CO₂ in packages while O₂ has increased by the end of storage. The microbiological results were within the established limits by law during the entire period. The shelf life of sous vide stored could be defined by N-TVB, TBARS, b* and C*, general acceptance, texture and flavor in 49 days of storage.Industrial relevanceThe development of sous vide with freshwater fish is an alternative for a value-added product to be supplied to market niches. Employing the sous vide technique on fish yields a product with better color, taste, texture, and nutrient retention than the traditional cooking processes, which makes it an attractive alternative for its consumption. This study aimed to prepare sous vide using captive pirarucu, tucupi and shrimp and to analyze the microbiological, physicochemical and sensory quality parameters during refrigerated in atmosphere modified packaging storage. The results of this study establish the product's shelf life (49 days) and contribute to defining processing and storage conditions for fish sous vide.     

Oxygen Availability Affects Prooxidant Catalyzed Lipid Oxidation of Cooked Turkey Patties

The catalytic effect of free ionic iron, hemoglobin and/or NaCI, and the effect of total lipid, class of lipid, and fatty acid composition on lipid oxidation of precooked refrigerated meat patties were highly significant only when oxygen was freely accessible to the patties during storage. With limited oxygen contact (cold vacuum-packaging) after cooking, the 2-thiobarbituric acid reactive substances (TBARS) values of patties were much lower than the values for patties with free oxygen contact (loose packaging) and did not increase substantially during storage. However, the TBARS values of cold packaged patties were higher (P<0.05) than those of hot packaged patties which had almost no oxygen contact after cooking. Elimination of oxygen during storage (hot or cold vacuum-packaging after cooking) resulted in prooxidants, fat content, fatty acid composition or the class of lipids having no effect on lipid oxidation.     

Stability of Polyunsaturated Fatty Acids after Microwave Cooking of Fish

The stability of fish oils high in polyunsaturated fatty acids (PUFA) in fresh fish of low, medium and high fat content was investigated using microwave oven cooking. Cooked and uncooked portions of butterfish, mullet, mackerel and sardines were extracted, the lipid recovered and fatty acid composition determined. The effect of cooking was minimal with no detectable difference in total lipid between cooked and uncooked samples. Most important, PUFA were virtually unaffected by the overall cooking and the cooked fish retained their original PUFA composition and content.     

Proximate and fatty acid composition and cholesterol content of different cuts of guinea fowl meat as affected by cooking method

BACKGROUND: Poultry is one of the leading meat products in South Africa, and its nutritional composition can be affected by the cut and cooking method. Limited food composition data are available for typical South African poultry products. This study investigated the effect of different cuts and cooking methods on the proximate and fatty acid composition as well as the cholesterol content of guinea fowl (Numida meleagris) meat. RESULTS: The open‐roasting method produced the highest moisture content for all cuts, and the baking bag method the lowest. The baking bag method resulted in the highest protein content. Cooking method had no effect on fat content, although breast had the lowest and thigh the highest fat content. Ash content was highest in the open‐roasted drumstick. All cuts, regardless of cooking method, had a favourable polyunsaturated/saturated fatty acid (P/S) ratio (>0.4). Their n‐6/n‐3 ratio was also within the recommended beneficial range (<4:1). Both cooking method and cut affected cholesterol content. CONCLUSION: Different cuts of guinea fowl vary in proximate and fatty acid composition as well as in cholesterol content, which in turn is affected to varying degrees by cooking method. Copyright © 2012 Society of Chemical Industry     

Process optimisation of pulsed electric fields pre-treatment to reduce the sous vide processing time of beef briskets

This study used multiple regression to model the effect of pulsed electric field (electric field strengths 0.7, 1.0 or 1.5 kV cm⁻¹) and sous vide (60 °C for either 12, 18 or 24 h) processing on the quality parameters (tenderness, cooking loss, colour, lipid stability) of beef brisket. Pulsed electric fields (PEF) at 0.7 kV cm⁻¹ and 1.5 kV cm⁻¹ followed by sous vide processing for 12–20.2 and 20.8–23.7 h, respectively gave the lowest values for hardness (<20.2 N), shear force (100.5 N mm⁻¹ s⁻¹) and cooking loss (<17.4%). PEF treatment prior to sous vide processing had no significant effect on lipid oxidation, colour stability, cooking loss or in vitro protein digestibility of sous vide-processed brisket. Increasing the electric field strength and/or prolonging the sous vide time significantly increased collagen solubilisation in the sous vide brisket. This study demonstrated that a PEF pre-treatment can reduce sous vide processing time while enhancing the tenderness of tough meat cuts.     

Consumer Acceptability and Sensory Profile of Cooked Broccoli with Mustard Seeds Added to Improve Chemoprotective Properties

Broccoli, a rich source of glucosinolates, is a commonly consumed vegetable of the Brassica family. Hydrolysis products of glucosinolates, isothiocyanates, have been associated with health benefits and contribute to the flavor of Brassica. However, boiling broccoli causes the myrosinase enzyme needed for hydrolysis to denature. In order to ensure hydrolysis, broccoli must either be mildly cooked or active sources of myrosinase, such as mustard seed powder, can be added postcooking. In this study, samples of broccoli were prepared in 6 different ways; standard boiling, standard boiling followed by the addition of mustard seeds, sous vide cooking at low temperature (70 °C) and sous vide cooking at higher temperature (100 °C) and sous vide cooking at higher temperature followed by the addition of mustard seeds at 2 different concentrations. The majority of consumers disliked the mildly cooked broccoli samples (70 °C, 12 min, sous vide) which had a hard and stringy texture. The highest mean consumer liking was for standard boiled samples (100 °C, 7 min). Addition of 1% mustard seed powder developed sensory attributes, such as pungency, burning sensation, mustard odor, and flavor. One cluster of consumers (32%) found mustard seeds to be a good complement to cooked broccoli; however, the majority disliked the mustard‐derived sensory attributes. Where the mustard seeds were partially processed, doubling the addition to 2% led to only the same level of mustard and pungent flavors as 1% unprocessed seeds, and mean consumer liking remained unaltered. This suggests that optimization of the addition level of partially processed mustard seeds may be a route to enhance bioactivity of cooked broccoli without compromising consumer acceptability.     

Enhanced resistance of mice (CBA strain) to infection caused by S. typhimurium depending on the nature of the fat in the diet

Mice received rations containing a mixture of lard with sunflower oil, butter, cooking fat (hydrogenated), fish fat. Hydrogenated fat and fish fat induced a decrease in the portion of polyunsaturated fatty acid omega 6 in lipids of lymphocytes, Peyer's patches, mesenteric lymph nodes and the spleen. At the same time fish fat induced an increase of the portion of polyunsaturated fatty acid omega 3 in lipids studied. A relationship has been noted between the animal survival after intraperitoneal infection with S. Typhimurium and the fatty acid composition in lymphoid tissues. The highest survival rate has been recorded in the groups of animals that received cooking (hydrogenated) fat and fish fat.     

Physicochemical and fatty acid characteristics of stewed pork as affected by cooking method and time

This study was designed to investigate the effects of cooking on physicochemical and fatty acid characteristics of stewed pork. Pre‐fried or raw pork belly cubes were stewed for 60, 90, 120, 150 or 180 min. After cooking, proximate chemical composition, texture, sensory evaluation, lipid oxidation, fatty acid profiles and cholesterol content were determined. Prolonged cooking time resulted in higher percentages of dry matter, fat and fat loss in stewed cubes (P < 0.01), and pre‐frying also increased fat loss. Tenderness and elasticity values of texture profile analysis and sensory scores were the highest for the cubes stewed for 180 min or by pre‐frying combined with stewing for 150 min. Pre‐frying and extended cooking time significantly increased lipid oxidation (P < 0.01). Cooking modified fatty acid profiles which altered the derived cardiovascular indices, and reduced cholesterol content. Prolonged stewing improved eating quality and most nutritional values of pork belly.     

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.     

Concentration of Umami Compounds in Pork Meat and Cooking Juice with Different Cooking Times and Temperatures

This study examined the concentrations of umami compounds in pork loins cooked at 3 different temperatures and 3 different lengths of cooking times. The pork loins were cooked with the sous vide technique. The free amino acids (FAAs), glutamic acid and aspartic acid; the 5′‐nucleotides, inosine‐5′‐monophosphate (IMP) and adenosine‐5′‐monophosphate (AMP); and corresponding nucleoside inosine of the cooked meat and its released juice were determined by high‐performance liquid chromatography. Under the experimental conditions used, the cooking temperature played a more important role than the cooking time in the concentration of the analyzed compounds. The amino acid concentrations in the meat did not remain constant under these experimental conditions. The most notable effect observed was that of the cooking temperature and the higher amino acid concentrations in the released juice of meat cooked at 80 °C compared with 60 and 70 °C. This is most likely due to the heat induced hydrolysis of proteins and peptides releasing water soluble FAAs from the meat into the cooking juice. In this experiment, the cooking time and temperature had no influence on the IMP concentrations observed. However, the AMP concentrations increased with the increasing temperature and time. This suggests that the choice of time and temperature in sous vide cooking affects the nucleotide concentration of pork meat. The Sous vide technique proved to be a good technique to preserve the cooking juice and the results presented here show that cooking juice is rich in umami compounds, which can be used to provide a savory or brothy taste.     

正交设计法优化真空低温蒸煮鸡胸肉的加工工艺

以新鲜鸡胸肉为研究对象,将其在4℃环境下腌制后进行真空包装处理,并采用低温烹饪法进行蒸煮加工.在单因素实验基础上,以腌制时间、加热温度、加热时间为影响因素,以低温蒸煮鸡胸肉的感官评分为主要评价指标,进行正交试验分析.结果表明,在加热时间55 min、腌制时间25 min、加热温度80℃的工艺条件下,真空低温蒸煮鸡胸肉的...     

EFFECT OF COOKING OIL TYPE ON FINAL CHOLESTEROL CONTENT AND FATTY ACID COMPOSITION OF GROUND BEEF

The purpose of this study was to compare three oils for extraction of cholesterol when used to cook ground beef and to determine the effect of oil type on fatty acid composition of the ground beef. Ground beef (30 % fat) was cooked in 1 L of corn, canola or palm oil at 100–110C and then rinsed with 500 ml of boiling water, which significantly decreased ether-extractable fat. Control hamburger was skillet-fried without any added oil. Total lipids were extracted and analyzed for fatty acid composition and cholesterol content. Changes in fatty acid composition of residual fat on the meat after cooking reflected those of the oils used for cooking. Cholesterol was significantly lower in all oil-cooked hamburger than in the control. In conclusion, cooking ground beef in any of the three vegetable oils will extract cholesterol, and the lipid remaining after a boiling water rinse will contain fatty acids characteristic of the cooking oil.     

Physiochemical and Microbiological Quality of Lightly Processed Salmon (Salmo salar L.) Stored Under Modified Atmosphere

Low‐temperature cooking, such as sous vide, has become a favored method for processing seafood. For this method to be applicable for retail products, combinations with other processing steps are needed to keep the products safe and durable while maintaining high quality. The present experiments were designed to investigate the influence of low‐temperature treatment (40, 50, or 60 °C) in combination with various packaging technologies (modified atmosphere [MA] or soluble gas stabilization [SGS]) on both the microbial growth and the physiochemical quality. Salmon loins were either kept natural or inoculated with Listeria innocua prior to drying (16 to 18 hr) in either 100% CO₂ (SGS) or atmospheric air (MA packaging). All samples were sous vide treated, repackaged in MA, and stored at 4 °C for 24 days. The results showed shelf life to be significantly improved with the implementation of SGS, by prolonging the lag‐phase and slowing the growth rate of both naturally occurring and inoculated bacteria. Variations in packaging technology did not significantly influence any of the tested quality parameters, including drip loss, surface color, and texture. Growing consumer demand for lightly processed seafood products makes Listeria spp. an increasing problem. The present experiment, however, has shown that it is possible to lower processing temperatures to as little as 40 or 50 °C and still obtain inhibition of Listeria, but with improved chemical quality compared to traditional processing.