Rancidity Research Articles

Impact of Thyme Essential Oil on the Aroma Profile and Shelf Life of Vacuum-Packed Minced Turkey Meat.

There is considerable interest in the use of essential oils for food preservation, but their effect on the aroma profile of a product is poorly understood. This study investigated the effect of thyme essential oil (EO) addition at increasing concentrations (0.005, 0.01, 0.02, and 0.03% v/w) on the volatile compound composition of vacuum-packed minced turkey meat after storage for 8 days at 1-2 °C. The aroma profile of the meat was determined using the HS-SPME/GCMS (headspace solid-phase microextraction/gas chromatography-mass spectrometry) method. The results were also analysed by PCA (principal component analysis). The addition of thyme EO had a modifying effect on the aroma profile of meat-derived components, e.g., the formation of benzeneacetaldehyde, benzyl alcohol, 4,7-dimethylbenzofuran, hexathiane, hexanal, and 1-hexanol was reduced and the appearance of 9-hexadecenoic acid was observed in the stored samples. The increase in EO concentration affected the levels of its individual components in the meat headspace in different ways. In terms of fat rancidity indices, even a 0.005% addition of this essential oil significantly reduced the peroxide value. Quantitative descriptive analysis (QDA) showed that the addition of thyme EO reduced or masked the intensity of unpleasant odours associated with meat spoilage. In the aroma analysis, the turkey with 0.02% v/w EO scored highest, and pleasant citrus notes were found.

Application possibilities of triple-layer furcellaran film with hazelnut oil microemulsion for packing cod liver oil

Triple-layer films based on furcellaran were successfully produced, where the middle layer was enriched with a hazelnut oil microemulsion. SEM images showed good embedding of the emulsion in the furcellaran layer. The addition of microemulsions significantly decreased the thermal and mechanical properties of the films, where the tensile strength values decreased, while the elasticity values of the film were improved. The presence of the emulsion increased the hydrophilicity of the film surface. The developed films in the form of sachets were used for packaging and storing cod liver oil. Fish oil was stored in refrigerated conditions without access to light and at room temperature (22 °C ± 1 °C) with access to light for 3 months. The acid (AV), iodine (IV) and peroxide values (PV), as well as the profile of fatty acids, were determined for the cod liver oil samples. It was shown that the cod liver oil samples had a similar value of the acid number during storage, however, over time, the IV and PV values increased statistically significantly, which indicates the ongoing process of fat rancidity. Furthermore, 23 compounds were identified in the fatty acid profile. It was shown that the profile of fatty acids in the stored fish oil changed, and the direction of these changes varied and generally, significantly depended on the film type and conditions in which the fat was stored. This study shows the possibility to obtain biodegradable packaging based on furcellaran enriched with a hazelnut oil microemulsion but also underline how important it is to check the presented packaging material in terms of its potential application.

Fatty Liver Disease (Lipoid Liver Degeneration) of Indian Major Carps and Its Management

Fatty liver disease was observed in some of the private fish ponds around Bhubaneswar. Affected specimens, mostly, Catla catla were having the disease in varying degrees. There was mortalitv at advanced stages of the disease. On an examination of live as well as freshly dead specimens, the liver of the affected fish was found to be damaged due to fatty infiltration of hepatic cells. However, externally the fish appeared normal. Fish fed with poor quality feed with rancid fat developed the disease which could be successfully controlled by withdrawing the rancid feed and providing fresh feed with high protein (about 22%) content.

Обоснование рациональных режимов термического выделения липидов из жиросодержащих рыбных отходов

Many fish waste remaining during the cutting of fish (heads, entrails, bones) contain an increased amount of fat, which has a high biological value. Obtaining edible fat from them is not always possible due to safety requirements, and the production of feed fishmeal with standard quality indicators is difficult. The increased fat content of raw materials and the technology parameters contribute to the rapid rancidity of fat in flour and the formation of toxic substances. This raw material can be used to obtain fish oil with subsequent recommendations for use, taking into account the indicators of oxidative and hydrolytic spoilage and in accordance with the requirements of the standards. When the content of undesirable products is exceeded, it can be used for technical purposes or in industrial biotechnology, as a substrate for microbial synthesis of biodegradable biopolymers such as polyhydroxyalkanoates. In this paper, a thermal method for separating fat from the heads of mackerel and hot-smoked sprats, as waste products from fish canning enterprises in the Kaliningrad region, was studied. A high fat content in raw materials (respectively 24.9 and 20.3%) and its characteristics were established. The rational parameters of the hydromodulus (1:0.5 and 1:1.0) were determined during thermolysis of crushed sprat and mackerel raw materials, respectively, at a stirrer rotation speed in the thermoreactor of 15 rpm. Rational ranges of temperature and duration of thermal release of fat were determined in experiments using mathematical planning. The optimization parameters were the yield of fat, its acid and peroxide numbers. The maximum yield of fat from fish heads is achieved at a temperature of 73-94°C for 2 hours 15 minutes - 2 hours 45 minutes. However, at the same time, fat has increased values of acid and peroxide numbers. Obtaining high-quality fat with food indicators is recommended at a temperature of 68 - 83 ° C for 43 min. – 1 h 22 minutes.

Quality Assessment and Comparative Study of Value-added Giblet Pickle Incorporated with Red Calyces of Roselle (Hibiscus subdariffa) and Acetic Acid

Background: The present study was carried out to develop a suitable formulation for value added pickle out of chicken giblet by incorporating roselle and evaluate their physico-chemical properties, sensory attributes and shelf-life qualities through microbial count, extend of proteolysis and fat rancidity after packaging in normal food grade polyethylene packaging material stored at ambient temperature. Methods: The developed value added giblet pickle was standardised with 15% rosella. The comparison was made among the samples incorporated in paste, oven dried powdered and 4% acetic acid. Result: The addition of 15% roselle in paste form increased the overall acceptability as well as the product yield. The protein content of both the treatments was found to be higher compared to the control. The pH of control (3.06±0.04) ranged to 4.25±.07 in treatment. The water activity did not differ significantly in control and treatments and the value ranged from 0.94±0.12 to 0.95±0.04. Thiobarbituric acid value (TBARS), tyrosine values and microbial count significantly (p less than 0.05) increased during storage days in all the pickle samples. However, the increase in TBARS, tyrosine values and microbial load were within the recommended limits as per FSSAI for pickled meat products. From the above study, it can be conclude that value-added giblet pickle with good nutritive value and higher acceptability can be prepared by incorporating roselle at 15% level.

Antioxidant Additives in Fish Feeds

Aquaculture is a rapidly developing sector in recent years. For humans, one of the most important sources of protein is fish and other products from aquaculture. Antioxidants are used to prevent oxidation problems in the feeds used in the production of these products. The task of antioxidants is to prevent rancidity of fats and to keep feeds stable. Fish fed with oxidized feeds experience many negative effects such as growth retardation, low feed utilization, weak immune system and reduced resistance to diseases. As a result, it can cause great economic losses along with fish losses. Synthetic antioxidants have been used successfully for many years. However, in recent years, some restrictions and regulations have been introduced the use of synthetic antioxidants. Therefore, natural antioxidants have begun to replace synthetic antioxidants. The sources of natural antioxidants are quite abundant, such as fruits, vegetables, plant extracts, marine macro and microalgae. In recent years, research on these natural antioxidants and their use in fish feeds have been increasing.

고함량 식물성 단백질 소재를 이용한 대체 햄 개발

This was a basic research study conducted to develop plant-based ham that could replace the existing commercially available animal ham for the meat substitute market. The protein and carbohydrate contents of the developed ham analog (DHA) were higher than the commercial vegetable ham (CVH) available in the market. The essential amino acid of DHA was 37.23%, which was similar to that of commercially available ham. Among the essential amino acids, the leucine level was the highest in DHA and CVH, and meat ham (MH) had the highest levels of lysine. Among the non-essential amino acids, DHA, CVH and MH had the highest levels of glutamic acid. Brightness (L) was higher in MH, redness (a) was higher in DHA, and yellowness (b) was higher in CVH. MH had the highest hardness, and the cohesiveness and elasticity of DHA tended to be higher than that of MH. DHA exhibited increased fat rancidity and protein deterioration over time. DHA ranked significantly higher with respect to color, appearance, odor, taste, texture, and overall acceptability compared to CVH. The manufacturing method of the alternative ham developed in this study provides a scientific alternative meat formulation without a nutritionally significant difference compared to commercially available animal ham. Thus, these study results provide good basic data for research on alternative meat sources.

Development of a rapid test kit for qualitative analysis of rancidity in fats and oils

Development of a rapid test kit for qualitative analysis of rancidity in fats and oils

A review on losses and transformation mechanisms of common antioxidants

AbstractAntioxidants are considered to be one of the most effective ways to prevent and delay the rancidity of oils and fats, thus play an important role in the processing, packaging, and storage of oils, fats, and oleaginous foods. However, the losses of antioxidants inevitably occur while preventing the rancidity of oils and fats. In this work, the loss pathways and mechanisms of synthetic and natural antioxidants commonly used in oils, fats, and oleaginous foods systems during storage, use, and detection are critically reviewed. The discussion regarding the transformation of antioxidants or antioxidant models in various organic solvent systems is also covered as well as the fate, toxicities, and antioxidative activities of transformation products of antioxidants. At room temperature, antioxidants in oils and fats are mainly lost due to antioxidation with transformation products accumulated. Under thermal (heating and frying) condition, synthetic antioxidants are mainly lost due to volatilization, while natural antioxidants are mainly lost due to transformation. Under frying condition, adsorption also contributes to the losses of antioxidants. This review discusses some possible research directions regarding antioxidants applied in oils, fats and oleaginous foods, which is expected to benefit the use of antioxidants in food industry.

Effect of dehydration on instrumental sensory characteristics of bee pollen

Colombian beekeeping producers and academic sector are developing research projects for using bee products by developing and improving their nutritional and functional quality, especially new food products with bee pollen inclusion. Bee pollen is a promising raw material for the production of functional foods because of its bioactive characteristics. In this work sensory stability of wet pollen, sun dried pollen and cabin dried pollen was evaluated during accelerated storage at 30, 40 and 50°C, taking into account different parameters such as volatile compounds profile by using a commercial electronic nose, fracturability of bee pollen grains with texture analyzer, colour change in CIELAB scale using a commercial colorimeter and water activity. It was found that electronic nose allows differencing bee pollen samples according to their water activity and distinguishing different volatile compounds profiles presented during storage. Bee pollen samples with a high water activity showed volatile compounds profile major changes during storage as well as their colour change. Bee pollen samples with a low water activity presented a change in their smell associated with fat rancidity, which is directly related to the texture.

Descriptive sensory analysis of instant porridge from stored wholegrain and decorticated pearl millet flour cooked, stabilized and improved by using a low-cost extruder.

Pearl millet flour, particularly wholegrain flour, is highly susceptible to development of rancid aromas and flavors during storage. Grain decortication and extrusion cooking using a friction-heated single-screw extruder were investigated as potential flour stabilization processes. Raw and extruded wholegrain and decorticated grain pearl millet flours were stored at ambient (25°C) and elevated (40°C) temperatures for 6 months. A trained descriptive sensory panel developed a lexicon of 44 attributes to profile the aroma, flavor, and texture of porridges prepared from the flours. Grain decortication alone did not show an effect on the aroma and flavor profile of porridge. Extrusion cooking of both wholegrain and decorticated flours increased cereal-like aromas (branny, canned sweetcorn, sweet, and wheaty) and flavor (starchy), as well as stiffness and cohesiveness of the porridges. The porridges from the extruded pearl millet flours stored for up to 6 months at ambient and elevated temperatures did not show any indications of rancidity. In contrast, rancidity-associated aromas (chemical, painty, and soapy) and flavor (chemical) increased in porridges from the raw flours stored for 4weeks and longer. These results indicate that grain decortication did not sufficiently reduce fat content to prevent oxidation, while extrusion cooking stabilized the pearl millet flours. In addition, intensified "cereal-like" aromas and flavors were probably due to Maillard reactions occurring during extrusion cooking. Resulting aroma compounds could have been immobilized in the extruded matrix and not released during flour storage. The application of extrusion cooking with a simple friction-heated single-screw extruder is a viable process for both precooking and extending the shelf life of pearl millet flours. PRACTICAL APPLICATION: This study demonstrates the potential of extrusion cooking to precook wholegrain pearl millet while preventing fat rancidity in wholegrain pearl millet flour, thereby improving the sensory quality and stability of pearl millet food products. The extensive sensory characterization of pearl millet porridge-type foods can serve as a guidance tool for development, improvement, and quality control of pearl millet foods. Furthermore, it establishes the efficacy of simple friction-heated, single-screw extruders for commercial manufacture of ready-to-eat wholegrain pearl millet food products by small and medium scale entrepreneurs.

Effect of Adding Essential Oils of Caraway and Rosemary on Volatile Aroma Compounds Derived from Stored Vacuum Packaged Minced Turkey Meat

Abstract Changes in the odor of meat during its storage are one of the basic indicators affecting its assessment and possible disqualification. The aim of the study was to determine whether the addition of essential oils may affect the composition and concentration of volatile compounds included in the aroma of stored turkey meat. We investigated the effect of adding essential oil (EO) of caraway (0.02% v/w), rosemary (0.02% v/w) and a mixture of the two (0.01% each) on the composition of volatile compound fractions formed during 10-day storage of vacuum-packed minced turkey meat. The EOs used were also evaluated for their influence on microbial contamination (total viable count and lactic acid bacteria count), sensory quality (odor and taste) and the level of fat rancidity (acid value, peroxide value and p-anisidine value) and pH in chill-stored samples. In terms of sensory indicators, the greatest beneficial effect of adding EOs was noted in the odor of raw meat. Use of the HS-SPME/GC-MS (headspace-solid phase microextraction/gas chromatography-mass spectrometry) method showed that the addition of essential oils significantly reduced the amounts of benzeneacetaldehyde, 2-octenal and ethyl 2-methyloctanoate compared with the control sample. In addition, in the presence of essential oils of rosemary and caraway, decreases were noted in benzaldehyde and 9-octadecenal, respectively. These changes may potentially affect the reception of the odor. There was a beneficial effect of the EOs in reducing the levels of fat oxidation indicators, including peroxides. However, the oils at applied concentrations had no significant effect on the total viable count and LAB count.

Functional dairy products as a source of bioactive peptides and probiotics: current trends and future prospectives.

Milk is an incredibly healthy food world-wide. However, the 'lactase deficient' individuals cannot digest milk's carbohydrate lactose. A large part of the world population is depriving of highly beneficial milk proteins like casein, lactoalbumin, lactoglobulin, etc. due to lactose intolerance. Production of functional foods and bioactive peptides from milk with natural antioxidants and the addition of probiotics could be the best alternative to extend the use of milk functionalities. Among different probiotics, the lactic acid bacteria (LAB) like Lactobacillus delbrueckii sub sp. bulgaricus, Streptococcus thermophilus and some species of Bifidobacteria and their metabolites (paraprobiotics and postbiotics) have been given more preference to add in milk-derived functional foods. These species are generally considered as heat-tolerant, highly proteolytic, and peptidolytic towards milk proteins and they liberate smaller molecules of bioactive peptides during fermentation and other processes that stimulate the enzyme lactase to help people in digestion of milk carbohydrate lactose. Moreover, the incorporation of natural antioxidants in yoghurt and other dairy products prevents the rancidity of milk fat. The level of bioactive peptides produced in milk-derived functional foods can be determined by capillary zone electrophoresis, mass spectrometry, fractionation, and other modern assessment techniques. Commercial production of functional probiotic products with bioactive peptides could significantly contribute to reduce milk spoilage, enhance health benefits as well as the growth of the agro-processing industry.

Substitution of Synthetic Colorants by Betalain Pigment Extracted from Beetroot Peels in Baked Foods: Muffins

Synthetic colorants such as Carmoisine and Ponceau 4R are used to get the desired red color in red velvet cakes. These synthetic food colorants have detrimental health effects like carcinogenicity, hypersensitivity reactions, behavioral effects, etc. This study explores the use of beetroots as a source of betalain pigments to be used for natural food coloring. Betalains being thermally labile, many trials were carried out to stabilize the pigments at the high baking temperature. For practical applications, instead of mentioning 'Contains permitted synthetic color', it is beneficial both for the manufacturer and the consumer when it says 'Contains Natural color' on the nutritional label. Betalain pigments also have anti-oxidant properties. From a technological standpoint, the addition of betalain pigment delays oxidative rancidity of fats used in the muffins thus contributing towards longer shelf life.

Sourdough Technology as a Tool for the Development of Healthier Grain-Based Products: An Update

There has been growing demand by consumers for grain-based products with well-balanced nutritional profiles and health-promoting properties. The components of the flours obtained from different grains can be modified or improved at a nutritional level by using sourdough technology, which has gained increasing interest in recent years. Sourdough hydrolyse dietary fibre, reduces fat rancidity, and enables an increase in starch and protein digestibility, as well as vitamin levels and mineral bioavailability. In addition, bioactive compounds are synthesized during fermentation, while components that interfere with the digestion of grain-based products or digestion-linked pathologies, such as gluten sensitivity or gastrointestinal syndromes, are reduced. Finally, it has been observed that sourdough fermented products can play a role in gut microbiota regulation. Thanks to this health-promoting potential, sourdough can stand out among other fermentation processes and opens up a new range of healthier commercial products to be developed. The current review discusses the extensive research carried out in the last 15 years and aims at updating and deepening understanding on how sourdough can enhance the nutritional and health-related characteristics of the different components present in the grains.

Validation of the SafTest Peroxide Test Kit for the Measurement of the Peroxide Content of Oils, Tallows, Meat Meals, Potato Chips, and Grain-Based Snacks: AOAC Performance Tested MethodSM 101001.

Peroxide value is used as an indicator of oxidative degradation, off flavor, and rancidity in fat. Traditional methods are dependent on a fat extraction step to extract fat for subsequent titration of peroxides. The SafTest Peroxide Test offers a direct measurement of the peroxide value of vegetable oils, animal fats, meat meal and fish meal products, and potato chips, crackers, and other processed grain-based snack products using micro-analytical and membrane separation principles. The study objective is to validate the SafTest Peroxide Test in an internal study, two contracted studies, and an independent laboratory study. Calibration, LOQ, robustness, selectivity, matrix, shelf life, and lot-to-lot stability were evaluated. The practical dynamic range of the calibration is 0.00 to 0.20 meq/kg. LOQ was determined as 0.02 meq/kg for liquids analyzed neat and 0.08 to 0.46 meq/kg for dry matrixes requiring a 1:4 to a 1:8 dilution. SafTest Peroxide Test relative standard deviations of repeatability (RSDr) averaged 1-13% compared to AOCS Cd 8-53 RSDr% of 1-15% and demonstrated average recoveries of 95.7, 91.5, and 105.2% of the AOCS Cd 8-53 results for olive oil, meat meal and fish, and animal fat and oils, respectively. The SafTest Peroxide Test is an acceptable alternative to AOCS Cd 8-53 and AOCS Cd 8 b-90 for the measurement of peroxide value in oils, fats, meat meal, fish meal, and snack products. The SafTest Peroxide Test uses small reagent volumes, eliminates fat extraction, and provides rapid and standardized procedures for the detection of peroxide.

Critical Evaluation of Methods for the Measurement of Oxidative Rancidity in Vegetable Oils

During storage and shipping, edible oils are susceptible to oxidative deterioration. To ensure high oil quality, it is essential to reliably analyze their oxidative status. The aim of this review was to critically evaluate published methods based on their value and applicability. This review focuses on major chemical, physical and chromatographic methods used for assessing the degree of lipid oxidation. Due to complexity of the mechanism of lipid oxidation, most of the methods determine either early or advanced oxidation products. Methods based on nuclear magnetic resonance spectroscopy, normal-phase high-performance liquid chromatography and high-performance size-exclusion chromatography are discussed as superior methods due to their capability of providing combined information about the extent of early and advanced oxidation stages.

Proximate Composition, Thiobarbituric Acid and Sensory Properties of Chicken-Breadfruit Patties with Piper guineense and Monodora myristica Oleoresins

The proximate composition, thiobarbituric acid value (TBA) and sensory properties of Piper guineense and Monodora myristica oleoresin spiced chicken-breadfruit patties at refrigerated storage for four weeks were evaluated. Breadfruit flour replaced 15 % of chicken and two concentrations (0.5 and 1 %) of P. guineense and M. myristica oleoresins were separately incorporated in the production of the patties. Moisture, protein and fat content of the patties varied significantly (P≤0.05) from 22.9 - 36.98 %, 11.14 - 18.13 % and 2.49 - 3.66 % respectively. Ash, fibre and carbohydrate ranged from 3.30 - 4.20 %, 0.84 - 4.61 % and 40.89 - 50.06 % respectively. The initial TBA values for the samples varied significantly (P≤0.05) from 2.96 - 3.51 mg maloadehyde/kg with an increase of 13 - 21. 17 - 24, 20 - 27 and 24 - 29 % at week 1, 2, 3 and 4 respectively. P. guineense and M. myristica oleoresins significantly (P≤0.05) reduced oxidative rancidity. Colour, flavour and overall acceptability of the patties decreased significantly (P≤0.05) from moderate likeness to slight dis-likeness. Breadfruit flour, P. guineense and M. myristica oleoresins will be of relevance in the production of an acceptable compositionally balanced chicken-breadfruit patties with less rancidity.

EZİNE ESKİ KAŞAR PEYNİRİNİN KARAKTERİSTİK BAZI ÖZELLİKLERİ

Çalışmada, Ezine ve Bayramiç ilçelerinde bulunan mandıralarda üretilen Ezine eski kaşar peynirlerinin bazı fiziksel, kimyasal ve duyusal özelliklerinin belirlenmesi amaçlanmıştır. Peynirlerin genel bileşiminin farklı olduğu, renk ölçümleri ve toplam serbest aminoasit, hidrolitik ransidite ve olgunlaşma düzeyleri arasında da farklılıklar olduğu görülmüştür. Özellikle, peynirlerin sertlik ve sakızımsılık ölçümleri arasında geniş varyasyon olduğu saptanmıştır. Peynirlerde belirlenen karakteristik bazı duyusal terimleri pişmiş, peyniraltı suyu, kremamsı, sülfür, ransit, tuzlu ve umamidir. Uçucu bileşen kompozisyonunun belirlenmesi için altı peynir örneği seçilmiştir. Aldehitler, ketonlar, alkoller, asitler ve esterler analiz edilen peynirlerde belirlenen yaygın uçucu bileşenlerdir.

Storage stability determination of calorie deficit gluten‐free biscuit: Taguchi concern

In this study, optimal process parameters were assessed for selection of storage-specific packaging material for gluten-free biscuit by means of Taguchi’s, L27 orthogonal array (Qualitek-4). An optimized blend of minimally preprocessed foxtail millet, amaranth, and copra meal flour were baked to biscuits, packed in metalized biaxially oriented polypropylene, co-extruded polypropylene as test, and high-density polyethylene as control sample. Physicochemical (% moisture content and % free fatty acid content), sensory (texture and mouthfeel, aroma and flavor, and overall acceptability), and microbiological characteristics (total viable and yeast and mold count) were assessed for wholesomeness up to 84 days with priority of selection of biscuits stored at 30°C than for the samples placed at 40°C. Sensory factors are on foremost concern regarding choice of stored biscuit sample that contributed maximally in terms of overall acceptability (73.97%) followed by texture and mouthfeel (11.56%), moisture (10.20%), and aroma (1.52%). Hence, Taguchi helped in logical studying the interactive effect for different parameters. Practical applications Biscuit is among the baked commodity whose quality diminishes with advancement of rancidity in fats and sogginess through moisture migration while storage days. It needed to be monitored with vast number of features to prove worth storage of the same. Type of packaging material, thickness of packaging material, temperature of storage, and number of advancement of storage days are continuously monitored in reference to the physicochemical (% FFA and % moisture content), sensory (aroma and flavor, texture, and mouthfeel and overall acceptability), and microflora count. To counter this huge range of experimental setup and wise interpretation for all of them only be feasible through Taguchi modeling to get effect of each factor individually.