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

Polysaccharide-based films and coatings for food packaging: A review

Color changes and acrylamide formation in fried potato slices

Background Bioactive molecules are mostly amenable to degradation at processing, storage, and harsh digestion conditions. Hence, high-throughput encapsulation bodies must be designed in a way to protect them from destructive circumstances and to enhance their bioavailability. Scope and approach This review article focuses on versatile mechanisms for gelation of globular proteins and highlights the current studies on whey and soy protein hydrogels as two key animal and herbal proteins used in fabricating coating materials. Moreover, different categories of hydrogels, such as aerated hydrogels, hydrogels made from aggregated forms of proteins, hydrogels originated from food-grade materials, and hydrogels with nano scale dimensions are discussed. Key findings and conclusions The gelation and particulation method have dramatic effects on the liberation features as well as the bioactivity of the wrapped ingredients. Therefore, different approaches are needed to be considered in order to increase the bioavailability of nutraceuticals and drugs accommodated within protein hydrogels. Accordingly, there is a growing trend for developing innovative modes of gelation and immobilizing bioactive materials into the hydrogel network.

Whey and soy protein-based hydrogels and nano-hydrogels as bioactive delivery systems

Carboxymethyl cellulose (CMC) is one of the most promising cellulose derivatives. Due to its characteristic surface properties, mechanical strength, tunable hydrophilicity, viscous properties, availability and abundance of raw materials, low-cost synthesis process, and likewise many contrasting aspects, it is now widely used in various advanced application fields, for example, food, paper, textile, and pharmaceutical industries, biomedical engineering, wastewater treatment, energy production, and storage energy production, and storage and so on. Many research articles have been reported on CMC, depending on their sources and application fields. Thus, a comprehensive and well-organized review is in great demand that can provide an up-to-date and in-depth review on CMC. Herein, this review aims to provide compact information of the synthesis to the advanced applications of this material in various fields. Finally, this article covers the insights of future CMC research that could guide researchers working in this prominent field.

https://www.mdpi.com/2073-4360/13/8/1345/pdf

Recent Developments of Carboxymethyl Cellulose.

Food industries search for replace synthetic surfactant with natural ingredients, but emulsifier type has an impact on lipid oxidation and stability of emulsions. The aim of the study was to evaluate the emulsifier type and concentration effect on avocado oil-based nanoemulsion development, specifically on physical and oxidative stability. O/W nanoemulsions were prepared with 10% avocado oil using natural (lecithin) and synthetic (Tween 80) emulsifiers at different concentrations (2.5–10%). Results showed that nanoemulsions exhibited anionic (Z-potential: − 26 to − 59 mV) lipid droplets with particle size between 103 and 249 nm. Emulsifier type and concentration affected physical stability, being the most stable at 7.5–10% Tween 80 (15 days) and 7.5–10% lecithin (10 days). Meanwhile, emulsifier concentration affected oxidative stability of nanoemulsions, being the most unstable at 2.5% Tween 80 and 10% lecithin. Finally, although Tween 80 was more effective than lecithin, it also could be used to develop natural nanoemulsions with good physical properties.

Comparing the effectiveness of natural and synthetic emulsifiers on oxidative and physical stability of avocado oil-based nanoemulsions

Physical properties of emulsion-based hydroxypropyl methylcellulose/whey protein isolate (HPMC/WPI) edible films.

Carboxymethyl cellulose (CMC) is a hydrocolloid with surface activity that could act as emulsifiers in oil-in-water emulsions; however the principal role is that it acts as structuring, thickening, or gelling agent in the aqueous phase. This study aims to evaluate the application of CMC as thickener into nanoemulsions based on olive oil and their influence on particle characteristics, flow behavior, and color. Four nanoemulsions with different oil (5% and 15% w/w olive oil) and CMC (0.5% and 0.75% w/w) concentration and two control samples without CMC added were prepared using Tween 80 as emulsifier. All physical properties studied on nanoemulsions were depending on both oil and CMC concentration. In general, z-average particle size varied among 107–121 nm and those samples with 5% oil and CMC were the most polydisperse. The addition of CMC increased anionic charge of nanoemulsions obtaining zeta potential values among −41 and −55 mV. The oil concentration increased both consistency and pseudoplasticity of samples, although samples were more stable to gravitational separation at the highest CMC concentration. Color of nanoemulsions was affected principally by the oil concentration. Finally, the results showed that CMC could be applied in nanoemulsions as thickener increasing their physical stability although modifying their physical properties.

/pdf/application-of-cmc-as-thickener-on-nanoemulsions-based-on-4tm99gpclc.pdf

Application of CMC as thickener on nanoemulsions based on olive oil: Physical properties and stability

Consumer demand for ‘natural’ products has led the food industry to substitute synthetic ingredients with others of natural origin. Nanoemulsions are thermodynamically unstable systems, so an emulsifier is necessary to maintain their stability during processing and storage. The aim of this work was to study the replacement of a synthetic emulsifier (Tw80: Tween 80) with one of natural origin (QS: quillaja saponins), evaluating its effect on the physical stability of nanoemulsions under different treatments (ionic strength and temperature). Avocado oil-based nanoemulsions were prepared using different emulsifier mixtures: 5% soy lecithin (SL) and 1% Tw80, which was replaced by different QS proportions (1:0, 3:1, 1:1, 1:3, 0:1 Tw80:QS). Results showed that by increasing QS proportion particle size, polydispersity index and electronegativity of nanoemulsions also increased. All nanoemulsions remain stable after centrifugation process, since no creaming formation was observed. The ionic strength treatment had an effect on zeta potential values, but not on PS. The incorporation of quillaja saponin in nanoemulsions increases their thermal stability. Thus, the ternary emulsifier mixture (Tw80-QS-SL) can be used in the elaboration of pasteurized and sterilized emulsion-based food products.

Rommy N. Zúñiga

Papers

Comparing the effectiveness of natural and synthetic emulsifiers on oxidative and physical stability of avocado oil-based nanoemulsions

Physical properties of emulsion-based hydroxypropyl methylcellulose/whey protein isolate (HPMC/WPI) edible films.

Application of CMC as thickener on nanoemulsions based on olive oil: Physical properties and stability

Physical stability of nanoemulsions with emulsifier mixtures: Replacement of tween 80 with quillaja saponin

Development of an in vitro mechanical gastric system (IMGS) with realistic peristalsis to assess lipid digestibility.