Effects of Biopolymers Encapsulations on the Lipid Digestibility of Emulsion-Type Sausages Using a Simulated Human Gastrointestinal Digestion Model

Stabilized soy protein emulsion enriched with silicon and containing or not methylcellulose as novel technological alternatives to reduce animal fat digestion

During the last decade, the consumption of animal saturated fat has been associated with an increased risk of chronic disease. Experience shows that changing the dietary habits of the population is a complicated and slow process, so technological strategies offer new possibilities for the development of functional foods. The present work is focused on studying the impact of using a food-grade non-ionic hydrocolloid (methylcellulose; MC) and/or the inclusion of silicon (Si) as a bioactive compound in pork lard emulsions stabilized with soy protein concentrate (SPC), on the structure, rheology, lipid digestibility and Si bioaccesibility during in vitro gastrointestinal digestion (GID). Four emulsions (SPC, SPC/Si, SPC/MC and SPC/MC/Si) were prepared with a final biopolymer (SPC and/or MC) concentration of 4% and 0.24% Si. The results showed a lower degree of lipid digestion in SPC/MC compared with SPC, specifically at the end of the intestinal phase. Moreover, Si partially reduced fat digestion only when incorporated into the SPC-stabilized emulsion, while this effect was lost in SPC/MC/Si. This was probably due to its retention inside the matrix emulsion, which resulted in lower bioaccesibility than in SPC/Si. Additionally, the correlation between the flow behavior index (n) and the lipid absorbable fraction was significant, suggesting that n can be a predictive marker of the extent of lipolysis. Concretely, our results revealed that SPC/Si and SPC/MC can be used as pork fat digestion reducers and thus, they can replace pork lard in the reformulation of animal products with potential health benefits.

Dietary Fiber from Soybean (Glycine max) Husk as Fat and Phosphate Replacer in Frankfurter Sausage: Effect on the Nutritional, Physicochemical and Nutraceutical Quality

The objective of the present study was to evaluate the effect of dietary fiber from soybean (glycine max) husk as fat and phosphate replacer on the nutritional, physicochemical, and nutraceutical quality of Frankfurter sausage. A traditional formulation was used for the pork-based sausage and three treatments were established: control treatment (CT), sausage without SHDF; treatment 1 (T1), sausage and 1% SHDF; treatment 2 (T2), sausage and 1.5% SHDF. T2 showed the best nutritional contribution of the treatments, significantly favoring a lower content of fat and sodium, thus increasing the contribution of dietary fiber and calcium. A positive effect of SHDF on the water-holding capacity of the treatments was also observed. In addition, T2 remained stable during storage, while T1 and CT showed significantly reduced water-holding capacities of approximately 5%; this was in turn linked to hardness, as it was observed that on day 7 of storage, 27% less force was required to deform the T2 sausages. Regarding color, no significant difference was observed with the addition of SHDF to the product. The results suggest that the dietary fiber extracted from soybean husks has potential for application in food and can be used as an ingredient to improve the functional and nutritional quality of Frankfurter sausages by reducing the content of fat and phosphates.

The Influence of Cellulose Ethers on the Physico-Chemical Properties, Structure and Lipid Digestibility of Animal Fat Emulsions Stabilized by Soy Protein

This study explores the influence of carboxymethylcelullose (CMC) and methylcelullose (MC), added by simultaneous (sim) and sequential (seq) emulsification methods, on the structure, rheological parameters and in vitro lipid digestibility of pork lard O/W emulsions stabilized by soy protein concentrate (SPC). Five emulsions (SPC, SPC/CMC-sim, SPC/CMC-seq SPC/MC-sim, SPC/MC-seq) were prepared in vitro. The presence of CMC and MC, and the stage of incorporation affected the emulsion microstructure. In the SPC emulsion, lipid droplets were entrapped by a protein layer that was thicker when MC was added, providing greater resistance against environmental stresses during gastrointestinal digestion. At 37 °C, CMC incorporation produced a structural reinforcement of the SPC emulsion, whereas MC addition did not affect the network rigidity, although a delaying effect on the crossover temperature was observed, which was more evident in SPC/MC–seq. The presence and stage of CMC and MC incorporation affected the rate and extent of lipolysis, with SPC/MC-seq presenting an inferior concentration of free fatty acids. The lower extent of lipolysis observed in SPC/MC-seq may be positive in the manufacture of animal fat products in which reduced fatty acid absorption is intended.

Analysis of in vitro digestion using human gut microbiota in adult and elderly individuals

In vitro human digestion models are widely used to determine the digestibility of bioactive substances and to perform drug delivery analyses. To develop the most accurate in vitro human digestion model reported to date, we simulated all digestion conditions, including pH and digestion time, with changes in the amount of digestive enzymes, motility, and proportion of human gut microbiota in adult and elderly individuals. Using this newly developed model, the digestibility of vitamin E emulsified by lard was found to be significantly different between adults and the elderly. Therefore, this model can accurately simulate oral, gastric, and intestinal (with gut microbiota effects) digestion of bioactive substances and can aid in analyzing drug delivery in adults and elderly individuals.

Variability in Phytochemical Contents and Biological Potential of Pomegranate (Punica granatum) Peel Extracts: Toward a New Opportunity for Minced Beef Meat Preservation

Extraction of Tunisian pomegranate peels was employed with different solvents such as ethyl acetate, acetonitrile, and water. Total phenolic and flavonoids contents, antioxidant activity, and antibacterial capacity against five foodborne pathogenic bacteria were evaluated. The highest values of polyphenols (351 mg gallic acid equivalent/g), flavonoids (104 mg quercetin/g), and DPPH and ABTS inhibition were recorded in the ethyl acetate extract followed by the aqueous extract. The latter present the maximum antibacterial potential against S. enterica, P. aeruginosa, and E. coli. The potential use of the lyophilized aqueous extract (AE), used for safety reason and being rich in phenolic, as biopreservative in minced beef meat was described. AE was incorporated at 0.1, 0.5, and 1% and compared with 0.1% butylated hydroxytoluene (BHT). During 21 days at 4°C, AE at 1% could appreciably retard the microflora proliferation (p<0.05), the accumulation of MetMb and the carbonyl group (p<0.05), slowing down the loss of sulphydryl proteins (p<0.05), and led to a decrease (p<0.05) in primary (peroxide value and conjugated dienes) and secondary lipid oxidation (TBARS) in treated meat. By the 14th day, AE-treated minced meat obtained higher sensory scores than untreated and BHT samples. Based on these results, lipid and protein oxidation changes and sensorial attributes were useful in discriminating meat samples by overall acceptability prediction. Generally, AE at 1% presented the potent preservative effect that could be utilized as an application on meat-substituting synthetic antioxidant.

Changes in the Content and Bioavailability of Onion Quercetin and Grape Resveratrol During In Vitro Human Digestion

We investigated the effects of in vitro human digestion on the content and bioavailability of onion quercetin and grape resveratrol caused by the composition of saliva or gastric, duodenal, or bile juice. We observed the digestibility of extracted onion quercetin and grape resveratrol, respectively, in the small intestine of the in vitro human digestion system. By liquid chromatography–mass spectroscopy, we found that the degradation of quercetin and resveratrol was influenced by small intestine digestion. Before and after in vitro human digestion, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of homogenized water- and ethanol-extracted grapes were higher than those of onion extracts. DPPH radical scavenging activity in both quercetin and resveratrol was decreased by in vitro digestion. These results will improve our understanding of how human digestion influences the contents and free radical scavenging activities of quercetin and resveratrol.

In Vitro Digestibility and Quality of an Emulsified Meat Product Formulated With Animal Fat Encapsulated With Pectin

Animal fat plays a key role in the structure, quality, and acceptability of emulsified meat products. However, a high consumption of saturated fat has been related to several health problems. Fat encapsulation with a nondigestible carbohydrate, such as pectin, may offer a promising alternative to reduce fat intake from a meat product, by preventing its digestion and absorption. The objective of this study was to develop a meat sausage with pectin-encapsulated-fat (PEF) to decrease its lipid digestibility, without compromising its acceptability. Pork fat particles encapsulation by emulsification with a 4% pectin solution, and also stability during meat processing and cooking, was confirmed by confocal microscopy. No changes (P > 0.05) compared to Control (C) were found on thermal stability and composition of sausages formulated with direct addition of pectin (T1) and with incorporation of PEF (T2). However, in comparison with C, pH, color, and texture of T1 and T2 samples were affected (P < 0.05). Nevertheless, these changes had no influence (P > 0.05) on sensory acceptability of treated samples, and actually improved (P < 0.05) their texture acceptance. In vitro digestive degradation of triacylglycerols was decreased (P < 0.05) by 20% on T2 samples compared to control and it was superior (P < 0.05) to T1 (8%). Confocal images confirmed lipid digestibility reduction of T2 samples. Incorporation of PEF in a meat sausage offers a better protection against the hydrolytic action of lipases over triaclyglycerides, than a direct addition of pectin, without affecting its sensory acceptability. Therefore, it can be a potential strategy to reduce fat intake from meat products. PRACTICAL APPLICATION: Reduction or replacement strategies tested to modify or decrease fat content in meat products usually leads to nondesirable sensory attributes. However, decreasing lipid digestibility by encapsulating animal fat with nondigestible pectin offers a new approach to reduce fat intake from full-animal-fat meat products, without affecting their sensory acceptability.

Health Risks of Food Oxidation

The impact of dietary habits on our health is indisputable. Consumer's concern on aging and age-related diseases challenges scientists to underline the potential role of food on the extension and guarantee of lifespan and healthspan. While some dietary components and habits are generally regarded as beneficial for our health, some others are being found to exert potential toxic effects and hence, contribute to the onset of particular health disorders. Among the latter, lipid and protein oxidation products formed during food production, storage, processing, and culinary preparation have been recently identified as potentially harmful to humans. Upon intake, food components are further degraded and oxidized during the subsequent digestion phases and the pool of compounds formed in the lumen is in close contact with the lamina propria of the intestines. Some of these oxidation products have been found to promote inflammatory conditions in the gut (i.e., bowel diseases) and are also reasonably linked to the onset of carcinogenic processes. Upon intestinal uptake, some species are distributed by the bloodstream causing an increase in oxidative stress markers and impairment of certain physiological processes through alteration of specific gene expression pathways. This chapter summarizes the most recent discoveries on this topic with particular stress on challenges that we face in the near future: understanding the molecular basis of disease, the suitability of using living animals vs in vitro model systems and the necessity of using massive genomic techniques and versatile mass spectrometric technology.