Effects of Turmeric, Shallot Extracts, and Their Combination on Quality Characteristics of Vacuum-Packaged Rainbow Trout Stored at 4 ± 1 °C

Applications of Essential Oils and Plant Extracts in Different Industries

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind's diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products without any pesticide and herbicide residues, and certified organic products command higher prices. EOs and plant extracts can be utilized as ingredients in plant antipathogens, biopesticides, and bioherbicides for the agricultural sector. Considering the need and the importance of using EOs and plant extracts in pharmaceutical and other industries, this review paper outlines the different aspects of the applications of these compounds in various sectors.

Effects of Turmeric, Cinnamon, and Lemon Extracts on Shelf Life, Nutrients, and Preservation of Carp Fish in Cold Storage

The present study aimed to investigate the effect of extracts of turmeric, cinnamon, and lemon on shelf life, macronutrients, and oxidative spoilage of the carp fish in cold storage at 4°C. Fishes were divided into five groups: control (NT); immersed fish in extracts of cinnamon, turmeric, and lemon (CTL); immersed fish in extracts of lemon and turmeric (LT); immersed fish in extracts of cinnamon and turmeric (CT); and immersed fish in extracts of lemon and cinnamon (LC). Results showed immersion of the carp fillet in extracts of turmeric, cinnamon, and lemon improved spoilage indices such as thiobarbituric acid, volatile nitrogen bases, and pH. The used extracts maintained the nutritional value and increased the fish’s shelf life. The compounds existed in the studied extracts decreased the values of the spoilage indices during cold storage. The highest spoilage indices were found for CL and CT treatments, and the lowest was for CTL treatment. The total bacterial load as well as the number of psychrophilic bacteria in the fish fillet found a significant decrease compared to the NT. Therefore, the best treatment was CTL, and inappropriate treatments were CT and CL. The fish shelf life for nine days was extended with the used extracts because the total count of cryophilic bacteria was 0.41 × 104 ± 0.50, which was the lowest compared to other treatments.

Recent developments of natural antimicrobials and antioxidants on fish and fishery food products

Fish and fishery products (FFP) are highly perishable due to their high nutritional value and moisture content. The spoilage is mainly caused by microorganisms and chemical reactions, especially lipid oxidation, leading to losses in quality and market value. Microbiological and lipid deteriorations of fishery-derived products directly lower their nutritive value and pose the risk of toxicity for human health. Increasing demand for safe FFP brings about the preservation using additives from natural origins without chemical additives due to their safety and strict regulation. Antimicrobials and antioxidants from natural sources have exhibited an excellent control over the growth of microorganisms causing fish spoilage via different mechanisms. They also play a major role in retarding lipid oxidation by acting at various stages of oxidation. Antimicrobials and antioxidants from natural sources are usually regarded as safe with no detrimental effects on the quality attributes of FFP. This review provides recent literature on the different antioxidant and antimicrobial agents from natural sources, focusing on microbial and oxidative spoilage mechanisms, their inhibition system, and their applications to retard spoilage, maintain safety, and extend the shelf life of FFP. Their applications and benefits have been revisited.

Curcuma longa L. Rhizome Essential Oil from Extraction to Its Agri-Food Applications. A Review

Curcuma longa L. rhizome essential oil is a valuable product in pharmaceutical industry due to its wide beneficial health effects. Novel applications in the agri-food industry where more sustainable extraction processes are required currently and safer substances are claimed for the consumer are being investigated. This review provides information regarding the conventional and recent extraction methods of C. longa rhizome oil, their characteristics and suitability to be applied at the industrial scale. In addition, variations in the chemical composition of C. longa rhizome and leaf essential oils regarding intrinsic and extrinsic factors and extraction methods are also analysed in order to select the most proper to obtain the most efficient activity. Finally, the potential applications of C. longa rhizome oil in the agri-food industry, such as antimicrobial, weedicide and a food preservative agent, are included. Regarding the data, C. longa rhizome essential oil may play a special role in the agri-food industry; however, further research to determine the application threshold so as not to damage crops or affect the organoleptic properties of food products, as well as efficient encapsulation techniques, are necessary for its implementation in global agriculture.

Review on Natural Preservatives for Extending Fish Shelf Life

Fish is extremely perishable as a result of rapid microbial growth naturally present in fish or from contamination. Synthetic preservatives are widely used in fish storage to extend shelf life and maintain quality and safety. However, consumer preferences for natural preservatives and concerns about the safety of synthetic preservatives have prompted the food industry to search natural preservatives. Natural preservatives from microorganisms, plants, and animals have been shown potential in replacing the chemical antimicrobials. Bacteriocins and organic acids from bacteria showed good antimicrobial activities against spoilage bacteria. Plant-derived antimicrobials could prolong fish shelf life and decrease lipid oxidation. Animal-derived antimicrobials also have good antimicrobial activities; however, their allergen risk should be paid attention. Moreover, some algae and mushroom species can also provide a potential source of new natural preservatives. Obviously, the natural preservatives could perform better in fish storage by combining with other hurdles such as non-thermal sterilization processing, modified atmosphere packaging, edible films and coatings.

Effect of combined application of Pimpinella affinis essential oil and extract in zein edible coating on vacuum packaged rainbow trout fillet quality

In the present study, the antioxidant and antimicrobial effects of essential oil (EO) and extract of Pimpinella affinis on the shelf life of rainbow trout during storage at refrigerator temperature based on three indicators of microbial, chemical and sensory quality parameters were evaluated. For this purpose, fish samples were stored in zein coatings containing 1.00% EO and 2.00% extract and in combination treatment containing 1.00% of each of them in refrigerator for 12 days. All of treatments were analyzed for microbiological count (Enterobacteriaceae, psychrophilic bacteria, mesophilic bacteria and pseudomonas bacteria) and chemical including pH, thiobarbituric acid reactive substances (TBARS), total volatile base nitrogen, peroxide value (POV) and free fatty acids (FFAs) and sensory (odor, color and texture) characteristics. Results showed that the highest levels of three factors including TBARS, POV and FFAs were related to the control sample and the least amount of these parameters was observed in EO and extract combination treatments. This effect of combined treatment was also observed in the reduction of total volatile basic nitrogen and pH parameters. Total bacterial counts during storage in fish treated with the extract and EO were remained below the acceptable level and microbial spoilage was significantly decreased compared to control. According to the sensory evaluation, treatments containing EO and extract showed improvement in this index compared to control treatment during storage. Based on the results of this study, it can be concluded that the EO and extract of P. affinis as active ingredients in zein coating successfully improve the quality and shelf life of the fish in the refrigerator.

Novel natural food preservatives and applications in seafood preservation: a review

Food preservative additives are natural or synthetic substances which delay degradation in foods caused by microbial growth, enzyme activity, and oxidation. Until recently, the use of synthetic additives in food was more common. However, synthetic additives have not been widely accepted by consumers in recent years due to their assumed adverse effects on their health. Therefore, the tendency of consumers to natural additives is increasing day-by-day. Seafood is an easily perishable food due to its chemical composition. Immediately after harvest, changes in odor, taste, and texture in fishery products can be noticed. For this reason, measures to protect the product must be taken immediately after harvest or catching. Various preservation methods have been developed. In addition to various technological methods, preservative additives are used in fresh or processed seafood as well as in other foods. This review focuses on novel natural preservatives from different sources such as plants, bacteria, fungi, animals and algae, and their use in seafood to protect quality and prolong shelf life. © 2018 Society of Chemical Industry.

Quality changes and shelf-life extension of ready-to-eat fish patties by adding encapsulated citric acid

BACKGROUND

Citric acid is commonly used as a flavoring and preservative in food and beverages. The effect of adding citric acid directly or encapsulated (each at 1 and 2 g kg^-1 ) on the quality and shelf-life of ready-to-eat sea bass patties was evaluated during storage at 4 °C in vacuum skin packaging.

RESULTS

Microbial growth and total basic volatile nitrogen were maintained at relatively low levels up to 8 weeks of storage. With respect to oxidative stability, the addition of encapsulated citric acid minimized secondary oxidation values more efficiently than its direct addition, regardless of the concentration. This is in agreement with the decreased fishy odor observed in those patties containing encapsulated citric acid. Accordingly, sensory analysis showed that the addition of encapsulated citric acid at 1 g kg^-1 resulted in lower scores in fish aroma compared to that of the control. Sourness is dependent on the amount of citric acid added, regardless of the form (direct or encapsulated).

CONCLUSIONS

The form of citric acid addition, rather than the amount of citric acid added, caused changes in texture. Therefore, the use of encapsulated citric acid represents a suitable strategy that is of great interest in the seafood industry. © 2017 Society of Chemical Industry.

Combined effects of lactoperoxidase system-whey protein coating and modified atmosphere packaging on the microbiological, chemical and sensory attributes of Pike-Perch fillets

The present study aimed to evaluate the efficacy of lactoperoxidase system-whey protein coating and modified atmosphere packaging (60% CO2, 30% N2, 10% O2) combination (LPOS + WPS + MAP) on the microbiological, chemical and sensory specifications of Pike-Perch (Sander Lucioperca, Linnaeus 1758) fillets. The highest bacterial count was observed in the fish fillets packaged with whey protein coating solutions (WPS) in compare with the other groups. Combination of WPS + LPOS and MAP packaging could significantly inhibit bacterial growth. Total volatile basic nitrogen (TVB-N), as a quality index of flesh, had strong correlation (r = 0.98-0.99) with microbial load, so that the highest and the lowest TVB-N values were observed in WPS and WPS + LPOS + MAP batches, respectively. Assessments of thiobarbituric acid reactive substances index showed that incorporation of LPOS with WPS or MAP did not have remarkable effect on lipid oxidation, but combined effect of MAP and WPS + LPOS on reducing fat oxidation was significant. The pH values in WPS + LPOS, WPS + MAP and WPS + LPOS + MAP were significantly lower than WPS. Sensory evaluations indicated that LPOS + WPS + MAP kept Pike-Perch fillets at high sensory acceptability for at least 16 days in refrigerated temperature. In conclusion, combination of MAP and WPS + LPOS showed synergistic effects on shelf-life extension of Pike-Perch fillets under refrigerated storage.

Combined effects of vacuum packaging and mint extract treatment on the biochemical, sensory and microbial changes of chill stored Indian mackerel

The present study was aimed to investigate the combined effects of vacuum packaging and mint extract treatment on the quality changes of gutted Indian mackerel (Rastrelliger kanagurta) during storage at 0-2 °C for 22 days. Biochemical, total viable count and sensory quality of chill stored mackerel were analysed at periodic intervals. Mint extract treated [dipping in 0.5% (w/v) solution of mint extract for 30 min] and vacuum packed fishes (MEVP) had significantly lower total volatile base nitrogen and trimethyl amine nitrogen compared to those packed under vacuum (CVP) and air (CAP) without mint extract treatment. Nucleotide degradation rate was lower in MEVP followed by CVP and CAP. Vacuum packaging in combination with ME treatment significantly inhibited lipid hydrolysis and lipid oxidation in mackerel as observed from its lower free fatty acid, peroxide value and thiobarbituric acid reactive substances values. Synergistic use of mint extract and vacuum packaging has markedly controlled microbial proliferation in the samples. Based on sensory evaluation, shelf life of Indian mackerel stored at 0-2 °C was determined as 13 days for CAP group, 16 days for CVP group and 21 days for MEVP group, respectively. The present study revealed that combination of vacuum packaging and mint extract treatment can be a promising technology to improve the storage quality of chill stored gutted mackerel.

Emerging Seafood Preservation Techniques to Extend Freshness and Minimize Vibrio Contamination

Globally, the popularity of seafood consumption is increasing exponentially. To meet the demands of a growing market, the seafood industry has increasingly been innovating ways to keep their products fresh and safe while increasing production. Marine environments harbor several species of indigenous microorganisms, some of which, including Vibrio spp., may be harmful to humans, and all of which are part of the natural microbiota of the seafood. After harvest, seafood products are often shipped over large geographic distances, sometimes for prolonged periods, during which the food must stay fresh and pathogen proliferation must be minimized. Upon arrival there is often a strong desire, arising from both culinary and nutritional considerations, to consume seafood products raw, or minimally cooked. This supply chain along with popular preferences have increased challenges for the seafood industry. This has resulted in a desire to develop methodologies that reduce pathogenic and spoilage organisms in seafood items to comply with regulations and result in minimal changes to the taste, texture, and nutritional content of the final product. This mini-review discusses and compares several emerging technologies, such as treatment with plant derived natural compounds, phage lysis, high-pressure processing, and irradiation for their ability to control pathogenic vibrios, limit the growth of spoilage organisms, and keep the desired organoleptic properties of the seafood product intact.

Efficacy of activated alginate-based nanocomposite films to control Listeria monocytogenes and spoilage flora in rainbow trout slice

Essential oils of clove, coriander, caraway, marjoram, cinnamon, and cumin were tested for their antilisterial activity by application of agar diffusion assay (experiment 1). Marjoram essential oil (MEO) showed the highest inhibitory effect, followed by clove and cinnamon. Subsequently, these essential oils were incorporated to alginate/clay nanocomposite films and antilisterial effectiveness of the films was studied in a model solid food system during 12 days at 10 °C (experiment 2). The results revealed that the films with MEO were more effective against Listeria monocytogenes in the model step. Finally, alginate-clay film incorporating 1 % MEO was applied to inoculated trout slices during refrigerated storage (4 °C) for 15 days (experiment 3). The control and the wrapped fish samples were analyzed periodically for microbiological (L. monocytogenes, total viable count, psychrotrophic count) and chemical (TVB-N) properties. The results demonstrated that alginate-clay films enriched with 1 % MEO significantly delayed the growth of L. monocytogenes during the 15-day storage with final counts reaching 6.23 log CFU/g while the counts in control samples were significantly higher reaching 7.38 log CFU/g (p < 0.05). Furthermore, active films efficiently reduced total viable count and psychrotrophic count as well as TVB-N in the fish slice during refrigerated storage.

Efficacy of mint (Mentha arvensis) leaf and citrus (Citrus aurantium) peel extracts as natural preservatives for shelf life extension of chill stored Indian mackerel

Efficacy of mint (Mentha arvensis) leaf and citrus (Citrus aurantium) peel extracts in retarding the quality changes in Indian mackerel during chilled storage was investigated. Mint leaf extract showed higher quantity of phenolics and superior in-vitro antioxidant activities than citrus peel extract. Gutted mackerel were given a dip treatment in mint extract (0.5 %, w/v) and citrus extract (1 % w/v), packed in LDPE pouches and stored at 0-2 °C. The biochemical quality indices viz. total volatile base nitrogen (TVB-N), trimethylamine nitrogen (TMA-N), free fattyacids (FFA) were significantly (p < 0.05) lower in mint extract (ME) treated fishes compared to citrus extract (CE) treated and control fishes (C) without any treatment. Plant extract treatment significantly inhibited lipid oxidation in mackerel as indicated by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). Aerobic plate count (APC) was markedly higher in C group followed by CE group throughout the storage period. As per sensory evaluation, shelf life of Indian mackerel was determined to be 11-13 days for C group, 13-15 days for CE group and 16-17 days for ME group, during storage at 0-2 °C.

Melatonin identified in meats and other food stuffs: potentially nutritional impact

Melatonin has been identified in primitive photosynthetic bacteria, fungi, plants, and animals including humans. Vegetables, fruits, cereals, wine, and beers all contain melatonin. However, the melatonin content in meats has not been reported previously. Here, for the first time, we report melatonin in meats, eggs, colostrum, and in other edible food products. The levels of melatonin measured by HPLC, in lamb, beef, pork, chicken, and fish, are comparable to other food stuffs (in the range of ng/g). These levels are significantly higher than melatonin concentrations in the blood of vertebrates. As melatonin is a potent antioxidant, its presence in the meat could contribute to shelf life duration as well as preserve their quality and taste. In addition, the consumption of these foods by humans or animals could have health benefits considering the important functions of melatonin as a potent free radical scavenger and antioxidant.

Antimicrobial activity of turmeric extract and its potential use in food industry

The present study investigates the antimicrobial and preservative potentials of turmeric extracts for food industry. Turmeric extracts prepared in n-hexane, water, chloroform and ethanol were applied to meals as preservatives and antibacterial agent. The samples were assessed microbiologically (total bacterial, total fungal and total coliform counts) and organoleptically (color, odor, taste) at day zero and after 15 days intervals. Meals autoclaved for shorter time (5 min) and treated with combination of 1 % or 2 % turmeric extract preserved for longer period. These results were comparable with samples autoclaved for longer period (15 min) with out turmeric extract. The antibacterial activities of different turmeric extracts were also tested against Escherichia coli, Staphylococcus aureus, Salmonella typhi and Candida albicans by disc diffusion method. Water extracted samples of turmeric stored at room temperature inhibited the growth of Escherichia coli and Salmonella typhi while aqueous extract autoclaved at 121 °C for 30 min reduced the growth of Escherichia coli and Staphylococcus aureus. Methanol extracted samples stored at room temperature or autoclaved at 121 °C was effective to control the growth of all microbes under study. Chloroform and n-hexane extracts (stored at room temperature) showed weak activity against all tested microbes.

Effect of the icing with thyme, oregano and clove extracts on quality parameters of gutted and beheaded anchovy (Engraulis encrasicholus) during chilled storage

The effect of ice containing thyme (0.04% w/v), oregano (0.03% w/v) and clove (0.02% w/v) extracts on the quality parameters of anchovy (Engraulis encrasicholus) was assessed through the chemical, sensory and microbiological methods. According to sensory analyses, anchovy stored in ice prepared with each plant extracts had a shelf life of 12 days, while batch stored in traditional ice had a shelf life of 9 days. pH were not significantly affected by the presence of plant extracts in the ice. However, a marked antioxidant effect (P<0.05) could be detected with fish kept under plant extract icing systems, according to peroxide (PV) and thiobarbituric acid (TBA) values. Moreover, the employment of such icing systems led to lower (P<0.05) total volatile base-nitrogen (TVB-N) value and free fatty acid (FFA) formation. Thus, TVB-N proved to be a suitable index for the spoilage of anchovies during chilled storage. The employment of such icing systems also led to significantly lower counts of aerobic mesophiles and psychrotrophic bacteria in anchovy muscle with skin, as compared with the traditional ice batch. This work demonstrates that the use of ice with plant extracts for the storage of gutted and beheaded anchovy can be recommended to improve the quality and extend the shelf life.

Multitargeting by turmeric, the golden spice: From kitchen to clinic

Although much has been published about curcumin, which is obtained from turmeric, comparatively little is known about turmeric itself. Turmeric, a golden spice obtained from the rhizome of the plant Curcuma longa, has been used to give color and taste to food preparations since ancient times. Traditionally, this spice has been used in Ayurveda and folk medicine for the treatment of such ailments as gynecological problems, gastric problems, hepatic disorders, infectious diseases, and blood disorders. Modern science has provided the scientific basis for the use of turmeric against such disorders. Various chemical constituents have been isolated from this spice, including polyphenols, sesquiterpenes, diterpenes, triterpenoids, sterols, and alkaloids. Curcumin, which constitutes 2-5% of turmeric, is perhaps the most-studied component. Although some of the activities of turmeric can be mimicked by curcumin, other activities are curcumin-independent. Cell-based studies have demonstrated the potential of turmeric as an antimicrobial, insecticidal, larvicidal, antimutagenic, radioprotector, and anticancer agent. Numerous animal studies have shown the potential of this spice against proinflammatory diseases, cancer, neurodegenerative diseases, depression, diabetes, obesity, and atherosclerosis. At the molecular level, this spice has been shown to modulate numerous cell-signaling pathways. In clinical trials, turmeric has shown efficacy against numerous human ailments including lupus nephritis, cancer, diabetes, irritable bowel syndrome, acne, and fibrosis. Thus, a spice originally common in the kitchen is now exhibiting activities in the clinic. In this review, we discuss the chemical constituents of turmeric, its biological activities, its molecular targets, and its potential in the clinic.

Plant extracts for the control of bacterial growth: efficacy, stability and safety issues for food application

The microbial safety of foods continues to be a major concern to consumers, regulatory agencies and food industries throughout the world. Many food preservation strategies have been used traditionally for the control of microbial spoilage in foods but the contamination of food and spoilage by microorganisms is a problem yet to be controlled adequately. Although synthetic antimicrobials are approved in many countries, the recent trend has been for use of natural preservatives, which necessitates the exploration of alternative sources of safe, effective and acceptable natural preservatives. Plants contain innumerable constituents and are valuable sources of new and biologically active molecules possessing antimicrobial properties. Plants extracts either as standardized extracts or as a source of pure compounds provide unlimited opportunities for control of microbial growth owing to their chemical diversity. Many plant extracts possess antimicrobial activity against a range of bacteria, yeast and molds, but the variations in quality and quantity of their bioactive constituents is the major detriments in their food use. Further, phytochemicals added to foods may be lost by various processing techniques. Several plant extracts or purified compounds intended for food use have been consumed by humans for thousands of years, but typical toxicological information is not available for them. Although international guidelines exist for the safety evaluation of food additives, owing to problems in standardization of plant extracts, typical toxicological values have not been assigned to them. Development of cost effective isolation procedures that yield standardized extracts as well as safety and toxicology evaluation of these antimicrobials requires a deeper investigation.