Insights into recent innovations in barrier resistance of edible films for food packaging applications.

The utilization of biopolymer-based food packaging holds significant promise in aligning with sustainability goals and enhancing food safety by offering a renewable, biodegradable, and safer alternative to traditional synthetic polymers. However, these biopolymer-derived films often exhibit poor barrier and mechanical properties, potentially limiting their commercial viability. Desirable barrier properties, such as moisture and oxygen resistance, are critical for preserving and maintaining the quality of packaged food products. This review comprehensively explores different traditional and advance methodologies employed to access the barrier properties of edible films. Additionally, this review thoroughly examines various approaches aimed at enhancing the barrier properties of edible films, such as the fabrication of multilayer films, the selection of biopolymers for composite films, as well as the integration of plasticizers, crosslinkers, hydrophobic agents, and nanocomposites. Moreover, the influence of process conditions, such as preparation techniques, homogenization, drying conditions, and rheological behavior, on the barrier properties of edible films has been discussed. The review provides valuable insights and knowledge for researchers and industry professionals to advance the use of biopolymer-based packaging materials and contribute to a more sustainable and food-safe future.

Effect of ß-glucan fortification on physico-chemical, rheological, textural, colour and organoleptic characteristics of low fat dahi.

Fortified low fat functional dahi prepared by supplementing skimmed buffalo milk with ß-glucan (0.25, 0.50, 0.75 and 1.0%) was assessed for physico-chemical, rheological, textural, colour and sensorial characteristics. Total solids in dahi increased significantly with the increase in ß-glucan concentration, however, values of fat, protein and ash varied non-significantly upon ß-glucan addition in dahi. ß-glucan at 0.5% solids levels, produced low fat dahi with superior quality, less whey separation and good textural properties than the samples containing other levels. Syneresis and viscosity was positively affected with the addition of ß-glucan till 0.5% level and higher concentration caused destabilization of the product. Fortified dahi showed greater firmness and consistent than control dahi sample. The addition of 0.5% level of ß-glucan also imparted significantly better instrumental color values and sensory scores with attractive or natural dahi color when compared to control dahi samples and other dahi samples prepared with different levels of ß-glucan.

Sensory characterization of doda burfi (Indian milk cake) using Principal Component Analysis.

Traditional sweetmeats of various countries hold a great and promising scope in their improvement and in order to tap the potential of the same, several companies and co-operative federations have started their organized production. Doda burfi, a heat desiccated and popular sweetmeat of northern India, is one of the regional specific, unfamiliarized products of India. The typical sweetmeat is characterized by caramelized and nutty flavour and granular texture. The purpose of this study was to determine the close relationship among various sensory attributes of the product collected from renowned manufacturers located in four different cities and to characterize an overall acceptable product. Individuals from academia participated in a round table discussion to generate descriptive terms related to colour and appearance, flavour and texture. Prior to sensory evaluation, sensory panel was trained and briefed about the terminology used to judge the product involving a descriptive intensity scale of 100 points for describing major sensory attributes. Results were analyzed using ANOVA and principal component analysis. Correlation table indicated a good degree of positive association between the attributes such as glossy appearance, dark colour, caramelized and nutty flavour and cohesive and chewy texture with the overall acceptability of the product.

Tuber-specific silencing of asparagine synthetase-1 reduces the acrylamide-forming potential of potatoes grown in the field without affecting tuber shape and yield.

Simultaneous silencing of asparagine synthetase (Ast)-1 and -2 limits asparagine (ASN) formation and, consequently, reduces the acrylamide-forming potential of tubers. The phenotype of silenced lines appears normal in the greenhouse, but field-grown tubers are small and cracked. Assessing the effects of silencing StAst1 and StAst2 individually, we found that yield drag was mainly linked to down-regulation of StAst2. Interestingly, tubers from untransformed scions grafted onto intragenic StAst1/2-silenced rootstock contained almost the same low ASN levels as those in the original silenced lines, indicating that ASN is mainly formed in tubers rather than being transported from leaves. This conclusion was further supported by the finding that overexpression of StAst2 caused ASN to accumulate in leaves but not tubers. Thus, ASN does not appear to be the main form of organic nitrogen transported from leaves to tubers. Because reduced ASN levels coincided with increased levels of glutamine, it appears likely that this alternative amide amino acid is mobilized to tubers, where it is converted into ASN by StAst1. Indeed, tuber-specific silencing of StAst1, but not of StAst2, was sufficient to substantially lower ASN formation in tubers. Extensive field studies demonstrated that the reduced acrylamide-forming potential achieved by tuber-specific StAst1 silencing did not affect the yield or quality of field-harvested tubers.

High hydrostatic pressure technology in dairy processing: a review.

Consumers demand high quality foods, which are fresh, tasty and nutritious; this has created considerable interest in the development of new food processing techniques. Presently, non-thermal techniques, including high hydrostatic pressure (HHP), are regarded with special interest by the food industry. Pressure ranges between 100 and 1200 MPa have been considered as effective to inactivate microorganisms including food-borne pathogens. HHP also improves rennet or acid coagulation of milk without any detrimental effect on flavour, body and texture and nutrients. Extended shelf-life and a "fresh-like" product presentation emphasize the need to take full account of food safety risks, alongside possible health benefits to consumers. These characteristics offer the dairy industry numerous practical applications to produce microbially safe and minimally processed dairy products with improved characteristics. Thus HHP is a powerful tool to develop novel dairy products of better nutritional and sensory quality, novel texture and increased shelf-life.

Transgene-induced silencing of Arabidopsis phytochrome A gene via exonic methylation.

Transgene-induced promoter or enhancer methylation clearly retards gene activity. While exonic methylation of genes is frequently observed in the RNAi process, only sporadic evidence has demonstrated its definitive role in gene suppression. Here, we report the isolation of a transcriptionally suppressed epi-allele of the Arabidopsis thaliana phytochrome A gene (PHYA) termed phyA' that shows methylation only in symmetric CG sites resident in exonic regions. These exonic modifications confer a strong phyA mutant phenotype, characterized by elongated hypocotyls in seedlings grown under continuous far-red light. De-methylation of phyA' in the DNA methyl transferase I (met1) mutant background increased PHYA expression and restored the wild-type phenotype, confirming the pivotal role of exonic CG methylation in maintaining the altered epigenetic state. PHYA epimutation was apparently induced by a transgene locus; however, it is stably maintained following segregation. Chromatin immunoprecipitation assays revealed association with dimethyl histone H3 lysine 9 (H3K9me2), a heterochromatic marker, within the phyA' coding region. Therefore, transgene-induced exonic methylation can lead to chromatin alteration that affects gene expression, most likely through reduction in the transcription rate.

Transgene expression produced by biolistic-mediated, site-specific gene integration is consistently inherited by the subsequent generations.

The efficient production of stable transgenic plants is important for both crop improvement and functional genomics. Site-specific integration of foreign genes into a designated genomic position is an attractive tool for minimizing expression variability between transgenic lines. Here, we studied the utility of a Cre-mediated, site-specific integration approach, facilitated by particle bombardment, for streamlining the production of stable transgenic plants, using rice as a model species. Using this method, we generated 18 different transgenic lines containing a precise integration of a single copy of beta-glucuronidase gene (gusA) into a designated genomic location. Eleven of these lines contained no illegitimate integration in the background (single-copy lines), and seven contained illegitimate integrations in addition to the site-specific integration (multicopy lines). We monitored gusA expression in these lines up to three to four successive generations. Each of the single-copy lines expressed the gusA gene at consistent levels and nearly doubled the expression level in the homozygous state. In contrast, multicopy lines displayed expression variation and gene silencing. In about half of the multicopy lines, however, expression of the site-specific integration locus could be reactivated and stabilized on segregation of the illegitimate integrations, whereas, in the remaining half, expression could not be restored, as they contained genetically linked illegitimate integrations. This study demonstrates that biolistic-mediated, site-specific gene integration is an efficient and reliable tool for streamlining the production of stable transgenic plants.

Roles for auxin during morphogenesis of the compound leaves of pea ( Pisum sativum).

The goal of this study was to explore the impact of the plant growth regulator auxin on the development of compound leaves in pea. Wildtype ( WT) plantlets, as well as those of two leaf mutants, acacia ( tl) and tendrilled acacia ( uni-tac) of pea ( Pisum sativum L.), were grown on media containing the auxin-transport inhibitors 2,3,5-triiodobenzoic acid (TIBA), N-(1-naphthyl)phthalamic acid (NPA), or the auxin antagonist, p-chlorophenoxyisobutyric acid (PCIB). The resulting plantlets were carefully analyzed morphologically, by scanning electron microscopy and for Uni gene expression using quantitative reverse transcription-polymerase chain reaction. Auxin transport was measured in WT leaf parts using [(14)C]indole-3-acetic acid. Relative Uni gene expression was determined in shoot tips of a range of leaf-form mutants. Morphological abnormalities were observed for all genotypes examined. The terminal tendrils on WT plants were converted to leaflets, stubs or were aborted. The number of pinna pairs produced on leaves was reduced, with the distal forms being eliminated before the proximal ones. Some leaves were converted to simple, including tri-and bilobed, forms. These treatments phenocopy the uni-tac and unifoliata ( uni) mutants of pea. In the most extreme situations, leaf blades were completely lost leaving only a pair of stipules or scale leaves. Polar auxin transport was basipetal for all leaf parts. Uni gene expression in shoot tips was significantly reduced in 60 microM NPA and TIBA. Uni mRNA was more abundant in tl, af and af tl and reduced in the uni mutants compared to WT. These results indicate that an auxin gradient plays fundamental roles in controlling morphogenesis in the compound leaves of pea and specifically it: (i). is the driving force for leaf growth and pinna determination; (ii). is necessary for pinna initiation; and (iii). controls subsequent pinna development.