Understanding retort processing: A review.

Retort processing is a food preservation technique to address the challenge posed by Clostridium botulinum for commercial sterility of a food product to get microbiologically safe and stable products by heating. This review aims to explore the journey of retort processing, starting from its early use in single-batch canned foods and progressing to its contemporary applications with different types of containers and heating mediums. Additionally, it will delve into the adaptability of retort equipment, including its ability to operate in stationary and various agitation states, as well as its flexibility in processing speed for both single-batch and continuous operations.

Value addition of rice straw cellulose fibers as a reinforcer in packaging applications.

The potential use of agro-waste in food packaging applications is receiving remarkable attention due to its sustainable approach and biodegradable properties. As typical lignocellulosic biomass, rice straw (RS) is widely produced but is usually abandoned and burned, causing tremendous environmental concerns. The exploration of using RS as the source of biodegradable packaging materials is promising for economically converting this agricultural waste into packaging material, thereby providing a considerable solution for RS disposal and an alternative solution to synthetic plastic waste. Polymers have been infused with nanoparticles, fibers, and whiskers, along with plasticizers and cross-linkers, and fillers like nanoparticles and fibers. They have also been blended with natural extracts, essential oils, and other synthetic and natural polymers to improve RS properties. There is still much research to be done before this biopolymer can be applied at an industrial level in food packaging. In this respect, RS can be valued for packaging to add value to these underutilized residues. This review article focuses on the extraction methods and functionality of cellulose fibers and their nanostructured forms from RS and their utilization in packaging applications.

Fabrication and characterization of active nanocomposite films loaded with cellulose nanocrystals stabilized Pickering emulsion of clove bud oil.

There is a tremendous increase in the development of alternative food packaging materials which are functional, environment-friendly, and can improve the shelf-life of food products. One such possible approach is to develop biopolymer-based active films loaded with antimicrobial essential oils. In the present study, pearl millet starch (PMS) films reinforced with kudzu cellulose nanocrystals (CNCs) stabilized Pickering emulsions of clove bud oil (CBO) were developed as active and sustainable packaging material. Active nanocomposite films were prepared by blending PMS with Pickering emulsions of CBO at 0.5, 1, 1.5, and 2 wt% conc. Using the solution casting method. Overall, active nanocomposite films displayed improved thermal, mechanical, and water barrier properties, with an optimum CBO-Pickering emulsion concentration of 1.5 %. CBO and PMS films showed strong chemical interactions, which significantly improved the mechanical resistance of the film. Further, SEM showed the appearance of micro-porous holes in the films because of partial evaporation on the cryo-fractured surface due to the vacuum condition. In addition, films exhibited antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with a rate response from increasing CBO Pickering emulsion concentration from 0.5 to 2 %. E. coli and S. aureus exhibited an inhibition zone ranging from 10.5 to 2.15 mm and 11.2 to 22.1 mm. This study suggests that PMS starch and kudzu CNCs-based active nanocomposite films loaded with CBO-Pickering emulsions have good potential to develop active and sustainable packaging materials.

Pearl millet starch-based nanocomposite films reinforced with Kudzu cellulose nanocrystals and essential oil: Effect on functionality and biodegradability.

This paper documents the preparation of three biopolymer films: 1) pearl millet starch (PMS) films, 2) PMS films reinforced with cellulose nanocrystals (CNCs), and 3) PMS films reinforced with CNCs stabilized Pickering emulsion of clove bud oil (CBO) and a comparison of their mechanical and water barrier properties and biodegradation behavior in soil. Reinforcing PMS films with Kudzu CNCs/CBO significantly increased tensile strength (from 3.9 to 16.7 MPa) and Young's modulus (from 90 to 376 MPa) but reduced the elongation (54.2 to 30 %) at the break of nanocomposite films. Also, the water vapor permeability of nanocomposite films decreased (from 9.60 to 7.25 × 10-10gm-1s- 1Pa-1) with the incorporation of Kudzu CNCs/CBO. The fastest biodegradation was observed for PMS films (98% in 15 days), followed by PMS films reinforced with Kudzu CNCs (96% in 18 days), followed by PMS films reinforced with Kudzu CNCs stabilized Pickering emulsions (94% in 21 days). The morphological analysis found hyphae-like structure formation due to microbial action, which increased over time. In general, all three biopolymer films showed good biodegradation behavior, and they all degraded between 15 and 21 days, suggesting that starch-based films reinforced with Kudzu CNCs provide a technique for the production of biodegradable packaging material.

Enzymatic modification of starch: A green approach for starch applications.

Native starches are modified to overcome the shortcoming, including retrogradation, syneresis, and low water-holding potential, which limit their industrial applications. The enzymatic modification includes designing a starch with a new structure. The molecular mass, branch chain-length distribution, and amylose/amylopectin ratio can be altered by enzymatic reactions when the enzymes react with gelatinized starch. The enzymatic modification directly affects the properties of the modified starch, including in freeze-thaw stability of gels and retardation of retrogradation during storage. Various enzymatic modifications of starch have been attempted for novel applications to the food industry as food ingredients, the enhancement of product quality, and the improvement of the efficiency of food processing. This review article addresses the key enzymes used for starch modifications, their mechanism of action, functionality and discusses new challenges and opportunities for effective modification. Also, the current review will give a critical snapshot of the applications for starch modifications in food industries.

Starch-based bio-nanocomposites films reinforced with cellulosic nanocrystals extracted from Kudzu (Pueraria montana) vine.

In the current study, starch-based active nanocomposite films reinforced with cellulosic nanocrystals (CNCs) of Kudzu were developed as an alternative option to existing biodegradable plastic packaging. Firstly, Kudzu CNCs were prepared by subjecting Kudzu fibers to the processes such as depolymerization followed by bleaching, acid hydrolysis, and mechanical dispersion. Further, nanocomposite films were formulated by blending pearl millet starch (PMS) and glycerol (30%) with different Kudzu CNCs compositions (0-7 wt%) using the solution casting process. The prepared PMS/Kudzu CNCs nanocomposite films were analyzed for their morphological (SEM and TEM), thermal (TGA and DSC), structural (FTIR), mechanical (tensile strength (TS), elongation at break and young modulus), and water barrier properties. The PMS/Kudzu CNCs films possessed improved crystallinity, heat and moisture-barrier properties, TS, and young-modulus after reinforcement. The optimum reinforcer concentration of CNCs was 5%. The Kudzu CNCs reinforced starch film offers a promising candidate for developing biodegradable films.

Nano-cellulose reinforced starch bio composite films- A review on green composites.

Plastic-based food packaging is generating a serious environmental problem by accumulating large amounts of plastic in the surroundings. Ecological and health concerns are driving research efforts for developing biodegradable films. There are few alternatives that could reduce the environmental impact; one of them is to substitute petroleum-based plastic with starch-based film. Starch has remarkable properties, including biodegradability, sustainability, abundancy, and capable of being modified or blended with other polymers. However, low mechanical strength and low water resistance restrict its application in food packaging. Nanocellulose isolated from lignocellulosic fibers has attracted tremendous interest in the field of science due to high crystallinity and mechanical strength, unique morphology along with abundancy, renewability, and biodegradability. Therefore, nano cellulose as a reinforcer proved to be a good option for fabricating biocomposites for food packaging. The current review will give a critical snapshot of the potential application of nanocellulose in food packaging and discuss new challenges and opportunities for starch biocomposites enriched with nano cellulose.

Mango seed starch: A sustainable and eco-friendly alternative to increasing industrial requirements.

During processing of mango (Mangifera indica) into beverages, squashes and jellies, by-products such as peel and kernel are generated. The higher generation volume of mango-seed makes it cheaper and readily available material for extraction of starch. The current article addresses the mango-seed as potential source of starch over the conventional sources. The starch isolation, its composition structural morphology along with the various physicochemical properties are well discussed. Various modifications for improving the functionality of mango-seed starch (MSS) are comprehensively investigated based on the previous findings. Digestibility profile and glycaemic index of MSS reflected the presence of more resistant starch compared to other conventional starches; making it suitable ingredient for managing diabetes. The structure of mango seed starch can be easily manipulated using biological, chemical and physical methods for improving its application in the foods. Possible utilization of the MSS at large scale will improve the economic viability of the mango processing industries.

Pearl millet grain as an emerging source of starch: A review on its structure, physicochemical properties, functionalization, and industrial applications.

Pearl millet (Pennisetum glaucum (L.) R.Br.) is a sustainable and underutilized starch source, constituting up to 70 % starch in its grain. Pearl millet could be used as a cheaper source of starch as compared to other cereals for developing functional foods. This review is mainly focused on isolation methods, and chemical composition of the pearl millet starch (PMS). Techno-functional characteristics such as; gelatinization, pasting properties, solubility, swelling power, and digestibility to infer wider application of the PMS critically highlighted in the review. Native starches have limited functionalitiesfor food applications due to the instability in developed pastes and gels. A number of modifications (physical, mechanical and enzymatic) have been developed to increase the functionality and to obtain desired characteristics of PMS thus improving its utilization in food applications. Further, the utilization of native as well as modified PMS is also discussed comprehensively. In addition, a number of recommendations to further improve its functionality and increase its application are also discussed.