Simulated gastro-intestinal digestion is widely employed in many fields of food and nutritional sciences, as conducting human trials are often costly, resource intensive, and ethically disputable. As a consequence, in vitro alternatives that determine endpoints such as the bioaccessibility of nutrients and non-nutrients or the digestibility of macronutrients (e.g. lipids, proteins and carbohydrates) are used for screening and building new hypotheses. Various digestion models have been proposed, often impeding the possibility to compare results across research teams. For example, a large variety of enzymes from different sources such as of porcine, rabbit or human origin have been used, differing in their activity and characterization. Differences in pH, mineral type, ionic strength and digestion time, which alter enzyme activity and other phenomena, may also considerably alter results. Other parameters such as the presence of phospholipids, individual enzymes such as gastric lipase and digestive emulsifiers vs. their mixtures (e.g. pancreatin and bile salts), and the ratio of food bolus to digestive fluids, have also been discussed at length. In the present consensus paper, within the COST Infogest network, we propose a general standardised and practical static digestion method based on physiologically relevant conditions that can be applied for various endpoints, which may be amended to accommodate further specific requirements. A frameset of parameters including the oral, gastric and small intestinal digestion are outlined and their relevance discussed in relation to available in vivo data and enzymes. This consensus paper will give a detailed protocol and a line-by-line, guidance, recommendations and justifications but also limitation of the proposed model. This harmonised static, in vitro digestion method for food should aid the production of more comparable data in the future.

https://hal.archives-ouvertes.fr/hal-01209876/document

A standardised static in vitro digestion method suitable for food – an international consensus

Background Meat, fish and derived products are perishable food items with quick deterioration under improper storage. Edible films and/or coatings present an interesting approach to preserve and package these foods. These are composed of biopolymers generated from food industry wastes or underutilized sources of proteins, lipids, or polysaccharides that are biodegradable, edible and can act as carriers with active agents from natural sources. Scope and approach The protective effect of active films and coatings in meat, fish and derived products against quality decay during storage is described. This review reinforces the benefits of active films and coatings incorporated with natural extracts, essential oils, natural polymers, protein hydrolysates, enzymes, and nanocomponents (materials and emulsions) to extend the shelf life of both fresh and processed meat and fish. Key findings and conclusions Edible films and coatings with active components are suitable for the preservation of fish, meat and derived products. These packaging approaches enhance the storage period of these products by preventing moisture loss and purge accumulation; delaying microbial spoilage and restricting the growth of pathogenic microorganisms; slowing lipid, protein, and pigment oxidation; and prolonging the period that products are sensory acceptable. Moreover, active agents can also improve the sensory and quality characteristics of packaged products. The main concerns among consumers are awareness and safety whereas cost and large-scale preparation are the main concerns for professionals in the food industry. It can be concluded that edible films and coatings have promising future in preservation and packaging of meat, fish and derived products.

Edible films/coating with tailored properties for active packaging of meat, fish and derived products

Aquatic, especially marine ecosystem is still an untapped reservoir of bioactive compounds, which have considerable potential to supply novel ingredients towards the development of commercial functional food products. Seafood products are an important part of the diet in many nations. Moreover, as a source of protein, seafood plays a significant role as functional components that are essential to human health. In industry or local seafood shops, processing of seafood generates a huge quantity (50–80%) of nonedible by-products, which are discarded as waste or underutilised in several parts of the world. These seafood processing by-products are rich sources of various novel and valuable biomolecules such as collagen and gelatin. In this review, scope of seafood by-products has been explored to recover the realistic collagen. The sustainable valorisation of seafood by-products may lead towards the development of healthy and functional food ingredients/products. Furthermore, the significant challenges towards the development of collagen-based functional food ingredients are also discussed. Industrial relevance With the increasing amount of seafood processing by-products worldwide, the recent trend towards the utilisation of collagen and their derived biomaterials to develop the various functional food and beverages is gaining momentum. Seafood processing by-products are a rich source of bioactive collagen molecules with potential nutraceutical/functional properties. Seafood processing industries are constantly trying to maximum utilisation of seafood by-products. This review article puts forward an alternative use of seafood processing by-products which may help to accelerate their business with significant benefits. The collagen-based novel functional food ingredient contains a nutritional benefit, such as essential and non-essential amino acid to improve the quality of different food products. It can also be used as natural antioxidants and texturing agents that will reduce the utilisation of chemical preservatives and may be able to fulfil the consumer demands for safe and green food products. In addition, the current status, challenges and the future directions in the development of seafood derived collagen peptides as functional ingredients is also discussed. This review suggests a biological solution for the disposal of the seafood processing by-products that creates an environmental pollution issues. This article reveals the opportunity to utilise the seafood by-products for the development of high value-added collagen-based functional food ingredients.

Sustainable valorisation of seafood by-products: Recovery of collagen and development of collagen-based novel functional food ingredients

Background Because of the important role of bioactive compounds in functional foods and health care, more and more attention has been paid to the active components extracted by green extraction methods. However, how to ensure the extraction yield and biological activity during the extraction process is an urgent problem to be solved. Subcritical water extraction (SWE) is a promising engineering method, which provides an environmentally friendly technology for extracting various bioactive compounds from natural products. Especially, under high temperature and high pressure, subcritical water can change the polarity and dielectric constant of solvents, thus contributing to a better extraction process, improving the mass transfer efficiency of the extracts and maintaining its biological activities, which has a high application prospect. Scope and approach This review provided an update overview on the fundamental principles and bioactive compounds extraction with subcritical water. This will contribute to deepen the understanding of SWE and provide theoretical basis and reference value for further improving the application of subcritical water. Key founds and conclusions It is expected that this green and efficient extraction technology will be increasingly applied in the extraction of more bioactive ingredients in the near future. In addition, future research should consider combining SWE with other physical extraction techniques to ensure the retention of the biological ingredients better. These active compounds with SWE have great potential in health care medicine and functional foods. Meanwhile, future researches should focus on consumer acceptability, safety, legal aspects, and commercial availability of health products.

Recent advances in the extraction of bioactive compounds with subcritical water: A review

Coupling hydrothermal liquefaction and anaerobic digestion for energy valorization from model biomass feedstocks

The use of sub-critical water hydrolysis for the recovery of peptides and free amino acids from food processing wastes. Review of sources and main parameters.

In this work, the preparation and evaluation of a low-cholesterol gluten-free bakery product has been investigated. For that purpose, in a muffin recipe, the full egg yolk was replaced by a low-cholesterol granular yolk fraction. In addition to the egg yolk recipe, three other formulations were elaborated: In the first preparation egg yolk was completely substituted by its weight in fresh granules (100% granules recipe). In the second one, the granules were lyophilized (lyophilized recipe) and reconstituted before their use. In another preparation, to further reduce the cholesterol content, all the egg yolk has been substituted by a lower amount of granules (60% granules recipe). Rheological batter characterization at 25 °C has shown that the viscoelastic properties of the recipes elaborated using 100% egg yolk granules and whole egg yolk were similar. Rheological characterization at 100 °C was performed too and differences were observed, with variations in the strength of the interaction in the batter produced by the granular components. Texture profile analysis has shown that all the recipes made using granules were harder than the one made with egg yolk.

Ismael Marcet

Papers

The use of sub-critical water hydrolysis for the recovery of peptides and free amino acids from food processing wastes. Review of sources and main parameters.

Egg yolk granules as low-cholesterol replacer of whole egg yolk in the preparation of gluten-free muffins

Production and characterisation of biodegradable PLA nanoparticles loaded with thymol to improve its antimicrobial effect

Egg yolk hydrolysed granules: Characteristics, rheological properties and applications

PLA nanoparticles loaded with thymol to improve its incorporation into gelatine films