Probiotics: A gut response to the COVID-19 pandemic but what does the evidence show?

Since the global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), research has focused on understanding the etiology of coronavirus disease 2019 (COVID-19). Identifying and developing prophylactic and therapeutics strategies to manage the pandemic is still of critical importance. Among potential targets, the role of the gut and lung microbiomes in COVID-19 has been questioned. Consequently, probiotics were touted as potential prophylactics and therapeutics for COVID-19. In this review we highlight the role of the gut and lung microbiome in COVID-19 and potential mechanisms of action of probiotics. We also discuss the progress of ongoing clinical trials for COVID-19 that aim to modulate the microbiome using probiotics in an effort to develop prophylactic and therapeutic strategies. To date, despite the large interest in this area of research, there is promising but limited evidence to suggest that probiotics are an effective prophylactic or treatment strategy for COVID-19. However, the role of the microbiome in pathogenesis and as a potential target for therapeutics of COVID-19 cannot be discounted.

Standardization of process protocol for isolation of starch from mango kernel and its characterization.

BACKGROUND: The major by-products of mango processing are the seeds, which represent approximately 15-20% of the fruit. The process protocol for isolation of starch from mango kernel was standardized based on starch yield, starch purity and colour values using centrifugation and chemical method. Optimized starches obtained from both methods were further investigated for estimation of functional properties and were characterized through Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and pasting properties analysis. RESULTS: The slurry making of mango kernels with a solid-to-water ratio of 1:3 at a centrifugation frequency of 3 times was found to be the best among all the experimental combinations (solid-to-water proportion (1:2, 1:3 and 1:4, w/v) and centrifugation frequency (2, 3 and 4 times)) with a starch yield of 48.43 ± 1.08% and purity of 76.46 ± 0.83%. In the chemical method of starch isolation (washing was done with 0.1 mol L-1 NaOH and 0.1 mol L-1 HCl at three levels each), the sample treated with 60% (w/v) 0.1 mol L-1 NaOH and 10% (w/v) 0.1 mol L-1 HCl resulted in 36.50 ± 0.58% starch yield with a purity of 92.03 ± 0.87%. Among the functional properties, the chemically isolated starch showed significantly higher paste clarity (45.79 ± 2.36%) than starch obtained using the centrifugation process (12.50 ± 1.57%). The chemically isolated starch also exhibited better colour attributes, which were very close to those of laboratory-grade starch. CONCLUSION: Detailed characterization studies inferred that both the starches possessed good functional, structural and thermal properties, indicating suitability for food and non-food applications. © 2021 Society of Chemical Industry.

The role of smart packaging system in food supply chain.

Food supply chain is a rapidly growing integrated sector and covers all the aspects from farm to fork, including manufacturing, packaging, distribution, storing, as well as further processing or cooking for consumption. Along this chain, smart packaging could impact the quality, safety, and sustainability of food. Packaging systems have evolved to be smarter with integration of emerging electronics and wireless communication and cloud data solutions. Although there are many factors causing the loss and waste issues for foods throughout the whole supply chain of food and there have been several articles showing the recent advances and breakthroughs in developing smart packaging systems, this review integrates these conceptual frameworks and technological applications and focuses on how innovative smart packaging solutions are beneficial to the overall quality and safety of food supply by enhancing product traceability and reducing the amount of food loss and waste. We start by introducing the concept of the management for the integrated food supply chain, which is critical in tactical and operational components that can enhance product traceability within the entire chain. Then we highlight the impact of smart packaging in reducing food loss and waste. We summarize the basic information of the common printing techniques for smart packaging system (sensor and indicator). Then, we discuss the potential challenges in the manufacturing and deployment of smart packaging systems, as well as their cost-related drawbacks and further steps in food supply chain.

In vitro digestibility of proteins from historical and modern wheat cultivars.

BACKGROUND: Previous research has suggested that proteins and other quality parameters of wheats may have changed over a century of wheat breeding. These changes may affect protein digestibility. The in vitro protein digestibility of breads made with 21 cultivars of wheat introduced or released in the USA between 1870 and 2013 was therefore evaluated. RESULTS: Protein digestibility increased with release year, but was not normally distributed; three older cultivars had significantly lower digestibility than the other cultivars: 42.0 ± 0.3 mol% (primary amino N/total N) versus 34.7 ± 0.7 mol%; P < 0.001. High molecular weight (MW) protein fractions increased and low MW protein fractions decreased with release year, but these changes were not related to protein digestibility. Thus, other differences in protein composition or other flour components may contribute to diminished digestibility of the three older cultivars. CONCLUSIONS: This study identified differences in protein digestibility among wheat cultivars that may have important implications for human nutrition. Further investigation is required to determine the specific characteristics that differentiate high- and low-digestibility wheat cultivars. © 2020 Society of Chemical Industry.

In Vitro Digestibility of Nanoporous Wheat Starch Aerogels.

This study reports the in vitro digestibility of starch aerogels for the first time. The relative crystallinities of the wheat starch aerogels (WSAs) produced at gelatinization temperatures of 120 °C (WSA-120C), 130 °C (WSA-130C), and 120 °C with the addition of sodium metaphosphate (STMP) (WSA-STMP) and xerogel were similar. However, WSA-120C showed the highest amylose-lipid complex content. The addition of STMP created some cross-linked starch with a phosphorus content of 0.023%. Resistant starch (RS) contents of WSA-STMP (33.5%) and xerogel (26.9%) were higher than the other samples when they were uncooked prior to digestion. Nevertheless, the RS contents of WSA-STMP and xerogel decreased drastically with cooking. RS contents of WSA-120C and WSA-130C were stable with cooking and provided 4.5- and 3.0-fold increases in the RS content, respectively. WSA is a promising functional food ingredient with a high RS content, even after cooking.

Moisture content during extrusion of oats impacts the initial fermentation metabolites and probiotic bacteria during extended fermentation by human fecal microbiota.

Extrusion exposes flour components to high pressure and shear during processing, which may affect the dietary fiber fermentability by human fecal microbiota. The objective of this study was to determine the effect of flour moisture content during extrusion on in vitro fermentation properties of whole grain oats. Extrudates were processed at three moisture levels (15%, 18%, and 21%) at fixed screw speed (300rpm) and temperature (130°C). The extrudates were then subjected to in vitro digestion and fermentation. Extrusion moisture significantly affected water-extractable ß-glucan (WE-BG) in the extrudates, with samples processed at 15% moisture (lowest) and 21% moisture (highest) having the highest concentration of WE-BG. After the first 8h of fermentation, more WE-BG remained in fermentation media in samples processed at 15% moisture compared with the other conditions. Also, extrusion moisture significantly affected the production of acetate, butyrate, and total SCFA by the microbiota during the first 8h of fermentation. Microbiota grown on extrudates processed at 18% moisture had the highest production of acetate and total SCFA, whereas bacteria grown on extrudates processed at 15% and 18% moisture had the highest butyrate production. After 24h of fermentation, samples processed at 15% moisture supported lower Bifidobacterium counts than those produced at other conditions, but had among the highest Lactobacillus counts. Thus, moisture content during extrusion significantly affects production of fermentation metabolites by the gut microbiota during the initial stages of fermentation, while also affecting probiotic bacteria counts during extended fermentation.