Quality properties of pork sausage prepared with water-soluble chitosan oligomer

Benefits of Essential Oil-Enriched Chitosan on Beef: From Appearance and Odour Improvement to Protection Against Blowfly Oviposition

The food industry is increasingly turning to healthy and eco-friendly alternatives for meat preservation, with recent attention focused on chitosan (CH) and essential oils (EOs). Here, we propose two liquid formulations of CH enriched with Laurus nobilis or Piper nigrum EOs to preserve beef patties stored for 4 days at 4 °C from colour changes, secondary lipid oxidation, and alteration in volatile organic compound emissions while also preventing oviposition by Calliphora vomitoria on beef loaves hung for the same time at around 13 °C in a netted polytunnel. Overall, the L. nobilis EO-enriched CH solution increased the meat colour lightness compared to the control (+7.58%), kept redness and yellowness comparable to the control, maintained the level of thiobarbituric acid-reacting substances below the threshold for rancidity perception for at least 96 h, reduced the release of ethanol, enhanced the perception of fatty and woody notes in the meat along with the fresh, green, and citrusy aromas specific to the EO, and also provided significant protection (88.83%) against blowfly oviposition compared to the control. Therefore, the development of a spray CH formulation containing the L. nobilis EO appears to be a promising tool for stable and prolonged meat protection.

Impact of nanoemulsion of Ajwain-cardamom essential oils on Mortadella sausage quality during chilling (4°C) storage

Essential oils application as natural preservatives is challenging owning to low solubility and stability to harsh conditions, while incorporation of essential oils into nanoemulsion systems can effectively improve these issues. Therefore, the nanoemulsion of ajwain (C. copticum) and cardamom essential oils were fabricated through self-emulsification technique and evaluated their size, ζ-potential, antioxidative and antibacterial activities. The effect of double nanomulsion on the textural and sensorial properties of Mortadella sausage was also examined under chilling temperature (4 °C). Our goal was to improve the chilling storage of Mortadella sausage by using ajwain and cardamom nanoemulsion as natural preservative. By increasing the ajwain essential oil in the nanoemulsion, the protein and moisture of sausage increased, while the fat content decreased (17 %). Furthermore, nanoemulsion of ajwain and cardamom essential oils showed particle size less than 100 nm and PDI<0.5 revealing the stability of nanoemulsions. Moreover, double nanoemulsions exhibited higher antibacterial activity against S. aureus and IC50 DPPH value (107 ppm). The nanoemulsion had a greater effect on the textural properties of Mortadella, reduction in hardness (∼5300 g), and chewiness (∼2500 g mm). Ajwain/cardamom nanoemulsion also increased the sensory properties, particularly taste and acceptance of the Mortadella. Consequently, Ajwain/cardamom nanoemulsion not only improve the storage of mortadella sausage at chilling temperature due to their antioxidant and antimicrobial properties, but also has a positive effect on the red color and textural properties created a special herbal aroma, taste and odor in the Mortadella samples, which ultimately contributed to the customer-friendly product. The appropriate dose of these nanoemulsion can develop meat products at lowest amount of nitrite in Mortadella sausage formulations, although, further research should be conducted on the mechanism of action AEO/CEO nanoemulsion concerning appearance and nitrite reduction in the meat products.

Chitosan with Natural Additives as a Potential Food Packaging

Recently, the development of materials based on natural polymers have been observed. This is the result of increasing environmental degradation, as well as increased awareness and consumer expectations. Many industries, especially the packaging industry, face challenges resulting from legal regulations. Chitin is the most common biopolymer right after cellulose and is used to produce chitosan. Due to the properties of chitosan, such as non-toxicity, biocompatibility, as well as antimicrobial properties, chitosan-based materials are used in many industries. Many studies have been conducted to determine the suitability of chitosan materials as food packaging, and their advantages and limitations have been identified. Thanks to the possibility of modifying the chitosan matrix by using natural additives, it is possible to strengthen the antioxidant and antimicrobial activity of chitosan films, which means that, in the near future, chitosan-based materials will be a more environmentally friendly alternative to the plastic packaging used so far. The article presents literature data on the most commonly used natural additives, such as essential oils, plant extracts, or polysaccharides, and their effects on antimicrobial, antioxidant, mechanical, barrier, and optical properties. The application of chitosan as a natural biopolymer in food packaging extends the shelf-life of various food products while simultaneously reducing the use of synthetic plastics, which in turn will have a positive impact on the natural environment. However, further research on chitosan and its combinations with various materials is still needed to extent the application of chitosan in food packaging and bring its application to industrial levels.

Chitosan and Essential Oils Combined for Beef Meat Protection against the Oviposition of Calliphora vomitoria, Water Loss, Lipid Peroxidation, and Colour Changes

Meat production has a higher economic and ecological impact than other commodities. The reduction in meat loss and waste throughout the whole supply chain is a demanding challenge. In recent years, the interest in the food-grade polysaccharide chitosan (CH) and essential oils (EOs) employed as allies in meat protection has increased. In this work, we selected five EOs obtained from plants traditionally used as spices, and after their chemical characterisation, a trained panel of expert sensorial analysts determined that, among them, Laurus nobilis (Lauraceae) and Piper nigrum (Piperaceae) EOs were the most suitable to season meat. Therefore, the effect of CH, the L. nobilis and P. nigrum EOs, and EOs-enriched CH solutions on meat was tested to assess how they deter the oviposition behaviour of the blowfly Calliphora vomitoria (Diptera: Calliphoridae) and against water loss, lipid peroxidation, and colour changes. All the applied treatments, compared to the control, did not accelerate meat dehydration but increased colour lightness, an attractive feature for consumers, and discouraged the blowfly's oviposition. In particular, the P. nigrum EO-enriched CH was the most active in repelling C. vomitoria without negatively affecting the organoleptic qualities and shelf-life of meat.

Effect of plant polyphenols on the physicochemical properties, residual nitrites, and N-nitrosamine formation in dry-fried bacon

Tea polyphenol (TP), apple polyphenol (AP), and cinnamon polyphenol (CP) are all enriched with antioxidant components, present enormous potential as natural antioxidants in meat products. The objective of this study was to evaluate the physicochemical properties, residual nitrites, and formation of N-nitrosamine (NA) in dry-fried bacons with three aforementioned plant polyphenols and ascorbic acid (AA). The results show that both plant polyphenols and AA significantly reduced pH, lipid oxidation and residual nitrite content when compared to the control (P < 0.05). Only AP exhibited a protective effect against protein oxidation-induced damage in bacon, and N-nitroso-methyl phenylamine (NMPhA) contents were significantly affected by plant polyphenols (P < 0.05). Bacon containing 300 mg/kg AP produced less thiobarbituric acid reactive substance (TBARS) (0.59 MDA/kg), carbonyl contents (2.30 nmol/mg protein) and NMPhA formation (1.211 ng/kg). In conclusion, plant polyphenols, particularly AP, have the potential to be used as natural antioxidants for reducing oxidation and nitrite application level while also improving the safety of bacon.

Incorporation of Low Molecular Weight Chitosan in a Low-Fat Beef Burger: Assessment of Technological Quality and Oxidative Stability

In the present work, incorporating low molecular weight chitosan (LMWCH) (0, 0.5, 1, and 2%) as a fat replacer into low-fat beef burgers and technological, textural, and oxidative stability were investigated. The weight loss and shrinkage of samples decreased with the increase of LMWCH concentration. In contrast, the water-holding capacity and color of burgers were enhanced by the addition of LMWCH. The instrumental TPA results indicated an increase in the LMWCH levels, significantly increasing the hardness, springiness, and gumminess but decreasing the cohesiveness of low-fat beef burgers. The TBARS and peroxide values and free fatty acid content in the burgers supplemented with LMWCH increase slower than the control sample during refrigerated storage.

Changes in moisture, colour, residual nitrites and N-nitrosamine accumulation of bacon induced by nitrite levels and dry-frying temperatures

The effects of different nitrite levels (50, 100, and 150 mg/kg meat) and dry-frying temperatures (100, 150, 200 and 250 °C) on the moisture movement, colour, sensory variables and residual nitrite and N-nitrosamine levels in smoked bacon were investigated. Increasing the dry-frying temperatures significantly increased the cooking loss and decreased the moisture content (P < 0.05). The bacon L*-values showed an increasing trend at first and then decreased, with the highest value of the bacon with 150 mg/kg nitrite was obtained at 100 °C and 150 °C. In addition, a*-values were significantly affected by the nitrite level and dry-frying temperature (P < 0.05), with the highest value of the bacon samples with 100 and 150 mg/kg nitrite observed at 250 °C. The residual nitrite content level initially increased (from unheated control to 150 °C) and then decreased (from 150 to 250 °C) sharply with increasing dry-frying temperatures in the bacon samples with the same sodium nitrite levels. N-methyl-N-nitrosoaniline (NMPhA) and N-nitrosomorpholine (NMOR) were measured in a number of smoked bacon samples, and a significant positive correlation (R² = 0.772) was found for N-nitrosamines (NA) contents and nitrite levels (P < 0.05). The maximum levels of NMPhA and NMOR were detected when the bacon with 150 mg/kg sodium nitrite was pan-fried at 200 °C and 150 °C, respectively.

Chitosan and Derivatives: Bioactivities and Application in Foods

Chitosan is a biodegradable, biocompatible, and nontoxic aminopolysaccharide. This review summarizes and discusses the structural modifications, including substitution, grafting copolymerization, cross-linking, and hydrolysis, utilized to improve the physicochemical properties and enhance the bioactivity and functionality of chitosan and related materials. This manuscript also reviews the current progress and potential of chitosan and its derivatives in body-weight management and antihyperlipidemic, antihyperglycemic, antihypertensive, antimicrobial antioxidant, anti-inflammatory, and immunostimulatory activities as well as their ability to interact with gut microbiota. In addition, the potential of chitosan and its derivatives as functional ingredients in food systems, such as film and coating materials, and delivery systems is discussed. This manuscript aims to provide up-to-date information to stimulate future discussion and research to promote the value-added utilization of chitosan in improving the safety, quality, nutritional value and health benefits, and sustainability of our food system while reducing the environmental hazards.

Functional foods and bioactive ingredients harnessed from the ocean: current status and future perspectives

With an increase in life expectancy and decrease of quality-of-life couple with the high prevalence of diseases, diet is expected to play a key function in sustaining human health. Nutritionists, food technologists and medical experts are working in synergy to cater for the increasing demand of food with associated therapeutic benefits, commonly known as functional food, that may improve well-being and reduce the risk of diseases. Interestingly, the marine ecosystem, due to its abundant and phenomenal biodiversity of marine organisms, constitutes a vital source of a panoply of healthy foods supply for the thriving functional food industry. Marine organisms such as seaweeds, sea cucumbers, sponges, and mollusks amongst others are sources of thousands of biologically active metabolites with antioxidant, anti-parasitic, antiviral, anti-inflammatory and anticancer properties. Given the growing number of research and interest to probe into the therapeutic roles of marine products, this review was designed to provide a comprehensive summary of the therapeutic properties of marine organisms (macroalgae, sea cucumbers and fish among others) which are consumed worldwide, in addition to their potentials and as sources of functional ingredients for developing novel food and fostering wellness. The gap between research development and actual commercialization, and future prospects of marine-based products also summarized to some extent.

Use of Turkey Meat Affected by White Striping Myopathy for the Development of Low-Fat Cooked Sausage Enriched with Chitosan

The main objective of this research was the development of a healthy meat product from turkey meat with white striping myopathy. The effect of adding different proportions of chitosan on the qualitative characteristics, sensory acceptance, and stability of cooked sausages during storage was studied. Three treatments were elaborated (control, 1.5% chitosan, and 3% chitosan), stored for 56 days, and characterized in terms of chemical composition, texture profile analysis, drip and pressure loss analysis, and sensory analysis (after processing; day 0). In the different storage periods (0 and 56 days), the pH value, color, thiobarbituric acid reactive substances (TBARS), and volatile compounds were evaluated. The results showed that the moisture content, lipids, proteins, and weight loss decreased (p < 0.05) and the ash content increased (p < 0.05) with the addition of chitosan. Similarly, the values of texture parameters (hardness, cohesiveness, gumminess, and chewiness) were higher in the sausages reformulated with chitosan than in control samples. The addition of chitosan increased the pH and yellowness (b*) values and reduced (p < 0.05) redness (a*) and lightness (L*) values. The b* values (only in reformulated sausages) and pH increased during storage, while a* showed a significant reduction after 56 storage days. Lipid oxidation (TBARS) was kept below the limits of quantification in all samples and both after processing and 56 storage days. However, when quantifying the lipid-derived volatiles, a clear antioxidant activity of chitosan was observed, which limits the release of these compounds, mainly aldehydes (hexanal and nonanal). Finally, the sensory analysis indicated that, although chitosan treatments received the lowest scores for all attributes, the reformulated samples did not differ from control sausages. Therefore, sausage containing chitosan may represent an interesting alternative for adding value to turkey meats affected by white striping myopathy and, at the same time, develop into a healthy and functional meat product increasing the proportion of fibers in one’s diet.

Synergistic effect of novel chitosan combined metformin drug on streptozotocin-induced diabetes mellitus rat

Metformin is widely used as a frontline medicine of type-II diabetes. Frequent overdose side-effects and their consequent adversative need to be reduced. The novel source of marine hydrozoa, Thyroscyphus ramosus derived chitosan combined metformin drug was administrated to evaluate the antidiabetic potential on a high-fat diet (HFD) with streptozotocin (STZ) induced diabetic rats. The primary analysis of In vitro antioxidant activity was tested for various solvent dissolved chitosan. Based on their IC₅₀ dose values, CsnAA was chosen for further experiments. The chitosan was combined with metformin by sonication and confirmed through XRD, FTIR and SEM analysis. The enhanced activity was observed in 100 mg/kg metformin combined with CSN500mg/kg. The level of serum bilirubin, total protein, SGH, liver glycogen, Glucose-6-phosphatase and fructose-1,6- phosphatase values were significantly similar to metformin 300 mg/kg treated group. With this beneficiary, the novel chitosan was recommended to administrate with metformin to improve the drug efficacy and reduction of overdose lethal effects.

Chitosan coatings incorporated with propolis extract and Zataria multiflora Boiss oil for active packaging of chicken breast meat

The impact of dipping in combination of propolis extract (PE) and chitosan (CH) coating enriched with Zataria multiflora essential oil (ZEO) on chemical, microbial and organoleptic properties of poultry meat was determined at 4 °C. GC-MS analysis showed that the most components of PE were Dihydrochrysin (9.69%) and b- Pinostrobin (7.41%). The results of mesophilic total viable plate counts (TVC), lactic acid bacteria (LAB), Psychotropic bacteria and Pseudomonas spp. showed detectably lower (p < 0.05) microbial count in CH-PE 1%-Z 0.5% and CH-PE 1%-Z 1% samples at the last day of storage. The results of chemical characteristics (pH, total volatile base nitrogen (TVB-N), 2-thiobarbituric acid reactive substances (TBARS)) in all treated samples compared with the control, revealed that there is a synergistic effect between CH, PE and ZEO. In the sensorial assessment, treatments containing 1% PE- 0.5% ZEO and 1% PE- 1% ZEO were mostly acceptable by the sensory analyst. These results offer a successful approach that chitosan coating enriched with combination of ZEO and PE can be an improving method to reducing deterioration of fresh packed chicken meat.

Combined Effects of Sodium Substitution and Addition of Cellulose or Chitosan on Quality Properties of Pork Sausages

The aim of this study was to assess the impacts of cellulose/chitosan addition in combination with sodium substitution, including KCl and MgCl2, on the quality and sensory properties of sausages. Sausages (control, 100% NaCl; T1, 60% NaCl, and 40% KCl; T2, 50% NaCl, 40% KCl, and 10% MgCl2) were formulated with cellulose/chitosan at concentrations of 3% and compared to control. T1 and T2 decreased the pH values (p<0.05), while the use of cellulose increased these values. Biopolymer addition reduced lipid oxidation (p<0.05). In sausages containing cellulose, volatile basic nitrogen (VBN) in T1 was lower than that in T2 (p<0.05). The use of cellulose increased L*-, a*-, and W color values in T1 (p<0.05). Furthermore, cellulose addition was associated with lower hardness (p<0.05). Cellulose addition contributed to better overall acceptability (p<0.05). Consequently, a combined mixture containing T1 and cellulose appears to be the best combination, indicating a possible synergistic effect.

The Impact of Chitosan-Divergicin Film on Growth of Listeria monocytogenes in Cold-Smoked Salmon

The aim of this study was to evaluate the impact of chitosan film, with bacteriocin divergicin 35 incorporate, on growth of Listeria monocytogenes in Cold smoked salmon. The simples of Cold-smoked wild salmon were inoculated with L. monocytogenes and treated with chitosan (100 kDa, 94.7% de-acetylated) and divergicin M35 was stored for 3 weeks at 4-8°C. The compounds were applied to the fish flesh in the form of solution or dried film. The film reduced L. monocytogenes to below the detection limit (<50 cfu/g) and kept total counts below 104 cfu per g compared to 109 cfu per g in control samples while the effectiveness of the solution was very limited. The inhibitory activity of the film lasted for 3 weeks, while the solution had no effect on L. monocytogenes counts measured on day 14. The film provided a better preservation of fish color (redness) and firmness than others treatments, while the solution had little impact on these parameters. It kept the volatile basic nitrogen (17.5 mg N/100 g) below the control value 29.9 mg N/100 g. Divergicin-loaded chitosan film thus may represent an interesting alternative for the bio-preservation of cold-smoked fish.

Preservative effects of sumac hydro-alcoholic extract and chitosan coating enriched along with Zataria multiflora Boiss essential oil on the quality of beef during storage

Beef is susceptible to rapid spoilage due to its high amount of protein (18.00%) and moisture (72.00%). Food industries have recently found methods to extend beef shelf-life. The influence of beef dipping in hydro-alcoholic extract of sumac (SE) and chitosan (CH) coating incorporated with Zataria multiflora essential oil (ZEO) on microbial, chemical and sensory quality of beef was evaluated during refrigerated storage. Total viable counts (TVC), lactic acid bacteria, Pseudomonas spp., Enterobacteriaceae and yeasts-molds, total volatile nitrogen (TVN), thiobarbituric acid reactive substance values (TBARS) and peroxide value (PV) were founded to be significantly lower in all treatment groups compare to control groups during storage time. The highest level of antimicrobial effects induced by chitosan, SE 4.00% and ZEO. We found that in TVC (3.69 log CFU g^-1 reduction compared with control group (sterile distilled water), Enterobacteriaceae (3.61 log CFU g^-1 reduction) and lactic acid bacteria (2.67 log CFU g^-1 reduction), respectively. Sumac gave a pleasant effect on sensory attributes and chitosan coating enriched with ZEO significantly improved sensory scores except for flavor factor. The results revealed the bio preservative properties of chitosan, hydro-alcoholic extract of sumac and Z. multiflora Boiss essential oil during refrigeration in normal packaging of beef.

Effects of chitosan as a surface fungus inhibitor on microbiological, physicochemical, oxidative and sensory characteristics of dry fermented sausages

The study aimed to improve the quality characteristics of Turkish dry-fermented sausages (sucuk) using different concentrations of chitosan (CH) coating as superficial mold inhibitor. The sausages were treated (w/w) with chitosan (0.2%, CH1; 0.5%, CH2 and 1%, CH3), potassium sorbate (20%, PS), acetic acid (1%, AA) and distilled water. Treatment with PS and CH3 resulted in a remarkable reduction of mold and yeast counts in the sausages and on casings at the end of ripening. Total aerobic mesophilic bacteria and lactic acid bacteria (LAB) varied from 7.19-7.29 to 9.01-9.27 and from 6.37-6.44 to 8.53-8.93 log CFU/g at day 0 and 12, respectively. Treatment with chitosan did not affect the natural microbiota of the sausages. Enterobacteriaceae counts were lowered from 5.79-5.89 to 2.08-2.53 log CFU/g by chitosan. Moreover, the rate of lipid oxidation in the sausages decreased by chitosan treatment. Sensory attributes were also notably enhanced in the cooked sausages treated with chitosan.

HDPE/Chitosan Blends Modified with Organobentonite Synthesized with Quaternary Ammonium Salt Impregnated Chitosan

In this study, blends based on a high density polyethylene (HDPE) and chitosan (CS) were successfully prepared by melt processing, in a laboratory internal mixer. The CS biopolymer content effect (up to maximum of 40%), and, the addition of bentonite clay modified with quaternary ammonium salt (CTAB) impregnated chitosan as a compatibilizing agent, on the properties of the blends was analyzed by Fourier transform-infrared spectroscopy (FT-IR), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile strength, and scanning electron microscopy (SEM). The use of clay modified with CTAB impregnated chitosan, employing a method developed here, improved the compatibility of HDPE with chitosan, and therefore the thermal and some of the mechanical properties were enhanced, making HDPE/chitosan blends suitable candidates for food packaging. It was possible to obtain products of synthetic polymer, HDPE, with natural polymer, chitosan, using a method very used industrially, with acceptable and more friendly properties to the environment, when compared to conventional synthetic polymers. In addition, due to the possibility of impregnated chitosan with quaternary ammonium salt exhibit higher antibacterial activity than neat chitosan, the HDPE/chitosan/organobentonite blends may be potentially applied in food containers to favor the preservation of food for a longer time in comparison to conventional materials.

Polysaccharide-Based Edible Coatings Containing Cellulase for Improved Preservation of Meat Quality during Storage

The objectives of this study were to optimize the composition of edible food coatings and to extend the shelf-life of pork meat. Initially, nine meat samples were coated with solutions containing chitosan and hydroxypropyl methylcellulose at various cellulase concentrations: 0%, 0.05%, and 0.1%, stored for 0, 7, and 14 days. Uncoated meat served as the controls. The samples were tested for pH, water activity (a_w), total number of microorganisms (TNM), psychrotrophs (P), number of yeast and molds (NYM), colour, and thiobarbituric acid-reactive substances (TBARS). The pH and a_w values varied from 5.42 to 5.54 and 0.919 to 0.926, respectively. The reductions in the TNM, P, and NYM after 14 days of storage were approximately 2.71 log cycles, 1.46 log cycles, and 0.78 log cycles, respectively. The enzyme addition improved the stability of the red colour. Significant reduction in TBARS was noted with the inclusion of cellulase in the coating material. Overall, this study provides a promising alternative method for the preservation of pork meat in industry.

Transparent bionanocomposite films based on chitosan and TEMPO-oxidized cellulose nanofibers with enhanced mechanical and barrier properties

The development of biobased active films for use in food packaging is increasing due to low cost, environmental appeal, renewability and availability. The objective of this research was to develop an effective and complete green approach for the production of bionanocomposite films with enhanced mechanical and barrier properties. This was accomplished by incorporating TEMPO-oxidized cellulose nanofibers (2,2,6,6-tetramethylpiperidine-1-oxyl radical) into a chitosan matrix. An aqueous suspension of chitosan (100-75wt%), sorbitol (25wt%) and TEMPO-oxidized cellulose nanofibers (TEMPO-CNFs, 0-25wt%) were cast in an oven at 40°C for 2-4days. Films were preconditioned at 25°C and 50% RH for characterization. The surface morphology of the films was revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thermal properties and crystal structure of the films were evaluated by thermogravimetric analysis (TGA-DTG) and X-ray diffraction (XRD). Incorporation of TEMPO-CNFs enhanced the mechanical strength of the films due to the high aspect ratio (3-20nm width, and 10-100nm length) of TEMPO-CNFs and strong interactions with the chitosan matrix. Oxygen and water vapor transmission rates for films that are prepared with chitosan and TEMPO-CNFs (15-25wt%) were significantly reduced. Furthermore, these bionanocomposite films had good thermal stability. Use of TEMPO-CNFs in this method makes it possible to produce bionanocomposite films that are flexible, transparent, and thus have potential in food packaging applications.

Effect of chitosans and chitooligosaccharides on the processing and storage quality of foods of animal and aquatic origin

Purpose

– The aim of the paper is to shed light on the use of chitosans and chitooligosaccharides as biopreservatives in various foods animal. Foods of animal and aquatic origin (milk, meat, fish, eggs, sea foods, etc) become contaminated with a wide range of microorganisms (bacteria, molds and yeasts) during harvesting, transporting, processing, handling and storage operations. Due to the perishable nature of these foods, their preservation is of utmost importance. Though many synthetic chemicals are available, yet their use is quite restricted due to their hazardous effects on human health.

Design/methodology/approach

– Within the domain of food industry, traditionally chitosan is used for biopreservation of foods, which is well known for its nutritional and medicinal properties in human nutrition. However, chitooligosaccharides also possess a number of nutraceutical and health promoting properties in addition to their preservative effect and shelf-life extension of foods. In this study, the comparative effects of both chitosan and chitooligosaccharides on preservation of foods of animal and aquatic origin have been summarized.

Findings

– Though chitosan has been extensively studied in various foods, yet the use of chitooligosaccharides has been relatively less explored. Chitooligosaccharides are bioactive molecules generated from chitosan and have several advantages over the traditional use of chitosan both in food products and on human health. But unfortunately, little or no literature is available on the use of chitooligosaccharides for preservation of some of the foods of animal origin. Notable examples in this category include cheese, beef, pork, chicken, fish, sea foods, etc.

Originality/value

– This paper focuses on the effects of chitosans and chitooligosaccharides on the processing and storage quality of foods of animal and aquatic origin, which offers a promising future for the development of functional foods.

A chitosan-based coating with or without clove oil extends the shelf life of cooked pork sausages in refrigerated storage

Chitosan coatings, with and without clove oil, were investigated for effects on quality and shelf life of cooked pork sausages stored at a refrigerated temperature (4±2°C). The various treatments of cooked pork sausages were: untreated (control), coating with 2% chitosan (CS), and coating with a mixture having 2% chitosan and 1.5% clove oil (CS+CO). Various microbiological, physical, chemical and sensory properties were monitored over 25 days of storage. The total viable count, the psychrotrophic bacteria count, the L* value, peroxide value and the thiobarbituric acid reactive substances increased, while the a* value, the b* value, the pH and the sensory scores decreased with storage time, across all treatments. However, these changes were slowest with the CS+CO treatment. Based on sensory evaluation and microbiological quality, the shelf lives were 14 days for control, 20 days for CS, and 20 days for CS+CO treated samples, under refrigerated storage.

Effect of packaging methods and crude aloe vera gel (Aloe vera barbadensis miller) on the storage quality of enrobed goat meat bites

The storage stability of enrobed goat meat bites (EGMB) incorporated with 3 % crude aloe vera (AV) gel was evaluated under aerobic (T-1; unenrobed control product, T-2; enrobed AV treated product) and modified atmospheric packaging (MAP, 50:50, CO2 and N2) (T-3; unenrobed control product, T-4; enrobed AV treated product) at 4 ± 1 °C for 42 days on the basis of physico-chemical, microbiological and sensory attributes. The pH value was higher, whereas water activity (aW) was lower in enrobed and MAP product. Thiobarbituric acid reacting substances (TBARS) and free fatty acid (FFA) values were significantly (P < 0.05) lower in MAP packaged (T-3) and AV treated products (T-2 and T-4) products than aerobic packaged (T-1), however it followed an increasing trend in all the products throughout storage. Instrumental colour and textural profile attributes were better maintained in MAP products than others. The sensory panellists graded T-4 'good to very good' even on Day 42, whereas T-1 was acceptable only up to 28 days. Standard Plate Count (SPC) was significantly (P < 0.05) lower in MAP products than aerobic packaged products. Results concluded that EGMB treated with AV gel can be successfully stored more than 42 days under MAP conditions without affecting its physico-chemical, textural, microbiological and sensory attributes.

Current understanding of synergistic interplay of chitosan nanoparticles and anticancer drugs: merits and challenges

Recent advances have been made in cancer chemotherapy through the development of conjugates for anticancer drugs. Many drugs have problems of poor stability, water insolubility, low selectivity, high toxicity, and side effects. Most of the chitosan nanoparticles showed to be good drug carriers because of their biocompatibility, biodegradability, and it can be readily modified. The anticancer drug with chitosan nanoparticles displays efficient anticancer effects with a decrease in the adverse effects of the original drug due to the predominant distribution into the tumor site and a gradual release of free drug from the conjugate which enhances drug solubility, stability, and efficiency. In this review, we discuss wider applications of numerous modified chitosan nanoparticles against different tumors and also focusing on the administration of anticancer drugs through various routes. We propose the interaction between nanosized drug carrier and tumor tissue to understand the synergistic interplay. Finally, we elaborate merits of drug delivery system at the tumor site, with emphasizing future challenges in cancer chemotherapy.