Development and characterization of edible films based on flaxseed gum incorporated with Piper betle extract.

There has been a shift from use of petroleum-based plastics, causing serious environmental pollution, towards innovative and biodegradable edible packaging. The present study documents the development of composite edible films based on the flaxseed gum (FSG) modified by the incorporation of betel leaf extract (BLE). The films were assessed for physicochemical, mechanical, morphological, thermal, antimicrobial and structural characteristics. Scanning electron microscopy images indicated that the roughness decreased with an increase in BLE concentration. The water vapor permeability of the FSG-BLE films ranged from 4.68 to 1.59 × 10-9 g s- 1 m- 2 Pa- 1, lower than that of the control sample (6.77 × 10-9 g s- 1 m- 2 Pa- 1). The BLE4 (containing 10 % BLE) films had the highest tensile strength of 32.46 MPa compared to the control sample (21.23 MPa). Similarly, EAB and seal strength of the films incorporated with BLE were ameliorated. X-ray diffraction pattern and FTIR illustrated the shift of amorphous to crystalline behavior and a significant interaction among the BLE and FSG functional groups. Furthermore, the thermal stability of the treated films was not affected significantly however, they showed improved antimicrobial activity with the highest diameter of inhibition zone in the BLE4 sample. This study concluded that the FSG-BLE composite films (BLE4 in particular) can be considered as novel packaging material for food conservation coupled with a potential to enhance the shelf life of perishable food products.

Characteristics of karaya gum based films: Amelioration by inclusion of Schisandra chinensis oil and its oleogel in the film formulation.

This research was focused to develop novel karaya gum films, modified by adding Schisandra chinensis oil and its oleogel. The films produced were assessed for physicochemical, mechanical, thermal and structural characteristics. Glass transition temperature (Tg) of control karaya gum films was recorded as 145.70 °C. Insignificant (p < 0.05) changes occurred in Tg of films in which oil was incorporated, irrespective of the concentration. However, Tg decreased significantly (p < 0.05) as oleogel was added to the karaya gum films and lowest Tg occurred for the KGOG3 films which contained highest concentration of oleogel. X-ray diffraction test depicted an obsolete amorphous behavior of control karaya gum film whereas some peaks appeared in other film samples. Scanning electron micrography (SEM) revealed a reduction in roughness and grainy morphology when oil or oleogel was added to the films. Addition of oil/oleogel enhanced the phenolic content and DPPH radical scavenging activity of the films.

Application of natural fruit extract and hydrocolloid-based coating to retain quality of fresh-cut melon.

Application of hydrocolloid based edible coatings is widely investigated as a promising means to retain quality and to extend the shelf life of food products. Present investigation was aimed to analyze influence of treatments, with different concentrations of lemon extract (0, 5, 10 and 15)% and coating with (0 and 5)% soy protein isolate (SPI), on fresh-cut melons. After the treatments, the samples were packed in polypropylene containers and kept at 4 °C for quality and shelf life analyses. The study involved 8 combinations of melon samples which were monitored in triplicate on specific days for different quality parameters including headspace gases, physicochemical, sensory and microbiological changes over the storage period. Lowest weight loss was indicated by samples treated with both lemon extract and soy protein isolate. When compared to control, coated samples indicated 4.36 log CFU/g lesser total plate count, and 2.39 log CFU/g lesser yeast and mold count at the completion of storage. Treatments showed effectiveness to retain vitamin C of melon samples. Total soluble solids, pH and titratable acidity varied remarkably through the storage life. Significant differences were observed in sensory attributes of control and coated samples. Chroma and color change (ΔE) values also reflected the potential of soy protein isolate coating to protect foods. Overall, the results suggested that lemon extract and soy protein isolate can help in retaining quality and extending the shelf life of fresh-cut melon.

Browning metabolism and quality of fresh-cut drumstick (Moringa oleifera) as influenced by acidulant treatments.

Though fresh-cut products save our time, but they are very much prone to enzymatic browning that drastically affects product's quality and marketability. Drumstick pods are considered as super food due to high nutritional contents. However, the fresh-cut pods are prone to brown discoloration. The enzyme activities promote the softening and cut-surface browning of pods, thus deteriorates their texture, decreases consumer appeal and shortens the shelf life. So, we aimed to assess the effect of citric (1%) and ascorbic (1%) acid treatments on quality attributes of fresh-cut drumsticks at 3-d interval during storage (5 ± 1 °C). In general there was an increase in lignin and quinone contents, while phenolic content was decreased during storage. However, samples subjected to ascorbic acid dip had higher phenolic content, lower rate of lignin formation, and reduced membrane permeability. Enzyme activities (polyphenol oxidase and peroxidase) were found to increase during storage, however, samples treated with ascorbic acid showed lower activities than that of the control and citric acid treated samples. The reduced enzyme activities resulted in the reduced browning incidence and maintained the quality. Therefore, postharvest dip of fresh-cut drumstick in to ascorbic acid (1%) could be suggested to increase the shelf life with reduced browning during low temperature storage.

Trends in foam mat drying of foods: Special emphasis on hybrid foam mat drying technology.

Dehydration of foods is not simply a preservation technique in the present era, rather an important food processing operation which has many benefits in addition to enhancement of shelf life of foods. There are various methods of drying foods and most of them are unique in their own way. Liquid foods can be dried in many ways and foam mat drying is one such method which is being researched frequently for its potential use at commercial level. Foam mat drying has got almost all the features to be a commercially successful method of drying. It is a simple technique and has shown good results in drying of liquid foods with low glass transition temperature. Hybridization of this method has shown the results that make this technology look even more promising than the conventional one. Studies on freeze drying, vacuum drying and microwave drying of foam have indicated encouraging results with respect to drying kinetics and product quality. This review presents an overview of foam mat drying of foods. The procedure and technology of this method of drying have been summarized with an intention to make them easy to understand. The emphasis is, however, on the hybrid foam mat drying technology.

Flaxseed gum in combination with lemongrass essential oil as an effective edible coating for ready-to-eat pomegranate arils.

Flaxseed gum (FSG) in combination with lemongrass essential oil (LGEO) was investigated for coating of ready-to-eat pomegranate arils. FSG was used at 0.3% and 0.6% concentrations and with both concentrations LGEO was incorporated at levels of 0ppm, 200ppm, 500ppm and 800ppm. Changes in headspace gases, physicochemical, microbiological and sensory attributes of pomegranate arils stored at 5°C were studied on different days of analysis during the 12day storage period. Coatings containing LGEO were effective in reducing total plate count and yeast and mold populations. Increasing LGEO concentrations in the coatings resulted in more decline in microbial populations. Reduced weight loss occurred in coated samples as compared to uncoated (control) sample. Coated samples showed a gradual decrease in ripening index in contrast with control where a significantly higher decline was observed. Total soluble solids, pH and titratable acidity significantly varied over the storage period. Color change (ΔE) for control increased steeply over the storage time in comparison to coated samples. Furthermore, chroma decreased while as hue angle increased over time.

Health Benefits of Anthocyanins and Their Encapsulation for Potential Use in Food Systems: A Review.

Anthocyanins are one of the six subgroups of large and widespread group of plant constituents known as flavonoids. These are responsible for the bright and attractive orange, red, purple, and blue colors of most fruits, vegetables, flowers and some cereal grains. More than 600 structurally distinct anthocyanins have been identified in nature. Earlier, anthocyanins were only known for their coloring properties but now interest in anthocyanin pigments has intensified because of their possible health benefits as dietary antioxidants, which help to prevent neuronal diseases, cardiovascular illnesses, cancer, diabetes, inflammation, and many such others diseases. Ability of anthocyanins to counter oxidants makes them atherosclerosis fighters. Therefore, anthocyanin-rich foods may help to boost overall health by offering an array of nutrients. However, the incorporation of anthocyanins into food and medical products is a challenging task due to their low stability toward environmental conditions during processing and storage. Encapsulation seems to be an efficient way to introduce such compounds into these products. Encapsulating agents act as a protector coat against ambient adverse conditions such as light, humidity, and oxygen. Encapsulated bioactive compounds are easier to handle and offer improved stability. The main objective of this review is to explore health benefits of anthocyanins and their extraction, characterization, encapsulation, and delivery.