Data for the validation of coffee silverskin extract as a novel food ingredient

Trabajo presentado a la 5th International ISEKI_Food Conference: "The Food system Approach: New Challenges for Education, Research and Industry", celebrada en Stuttgart (Alemania) del 3 al 5 de julio de 0218.The present investigation aimed to provide data on coffee silverskin extract (CSE) for its validation as a novel food ingredient. Male (n = 15) and female (n = 15) Wistar rats (average weight, 67 ± 4.7 g) received CSE (1 g/kg bw) or water (control group) by gavage once a day for 28 days, according to the OECD Guideline 407. Body weight and food and water intake were daily recorded. Twenty-four hours feces were collected from each cage once a week. Total blood was collected by cardiac puncture. Total antioxidant capacity (TAC), glutathione peroxidase (GPx), gluthathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) were analyzed in serum and red blood cells (RBCs) lysates. TAC and pH were measured in feces. ABTS assay was used for TAC analysis. TAC of CSE was 138.73 ± 14.8 mg eq. CGA/g. Daily administration of CSE (1 g/kg bw) for 28 days was not toxic. No changes in body weight and food and water intakes were observed. Treatment of rats with CSE did not significantly affect antioxidant biomarkers in blood samples. No significant changes in pH or TAC were observed in feces. No increase in excretion of antioxidant metabolites in feces after treatment with CSE for 28 days was detected by ABTS. These metabolites may be excreted in urine or accumulated in tissues and organs. The presence of caffeine, paraxanthine and hippuric acid (metabolites of caffeine and CGA, respectively) in urine of Wistar rats 8 hours after the ingestion of CSE, and protection of pancreatic cells of rats against oxidative stress produced by the diabetogenic agent STZ was reported. CSE (1 g/kg bw) can be considered a natural, sustainable and safe food ingredient. Further information is needed to find out its effective doses for supporting health claims described in C. elegans7 and diabetic Wistar rats models.Research funded by MINECO (AGL2014-57239-R, BES-2015-072191) and CM (S2013/ABI-2728).Peer reviewe

Effect of the repeated intake of coffee silverskin extract on the short-chain fatty acid profile of rat feces

Trabajo presentado al Fifth International Congress on Cocoa Coffee and Tea (Cocotea), celebrado en Bremen (Alemania) del 26 al 28 de junio de 2019.[Background] Coffee silverskin (CS) is a thin tegument of the outer layer of the green coffee bean and contains bioactive compounds, such as dietary fiber (28 %), among others. Dietary fiber is fermented in the large intestine by the microbiota leading to the generation of short-chain fatty acids (SCFAs) that contributing to human well-being.[Aim] The present investigation aimed to assess the effect of the repeated intake of coffee silverskin extract (CSE) and sex on the SCFAs profile of rat feces.[Methods] Male (n=15) and female Wistar rats (n=15) received CSE (1 g/kg bw) or water (control group) by gavage once a day for 28 days. The total dietary fiber intake was calculated as the sum of the fiber contents of the diet and CSE (Table 1). Previous studies have demonstrated the safety of CSE at the dose hereby employed. Feces from the last 24 h were collected from the treated and control groups and SCFAs were identified and quantified by using gas chromatography coupled to mass spectrometry (Agilent 7890A, Agilent 5975C).[Results] Rats treated with CSE had a significantly increased intake of dietary fiber (p < 0.05) (Table 1). The most abundant SCFAs found in feces were acetate, propionate and butyrate (Figure 1). Total SCFAs (60 μmol/g and 78 μmol/g for control and treated rats) were significantly increased (p < 0.05) in feces when male rats were treated with CSE. However, this effect was not observed in female rats (79 μmol/g and 73 μmol/g for control and treated rats). In male rats, acetate significantly increased (p < 0.05) in feces after the repeated intake of CSE, but propionate and butyrate levels were decreased.[Conclusion] Sex seems to influence the SCFAs profile of rats' feces. CSE fiber undergoes significant fermentation in male rats. CSE might be considered as a sustainable functional food ingredient with effect on the gut microbiota and health promoting properties associated to SCFAs.Research funded by MINECO (AGL2014 57239 R, BES 2015 072191) and CM (S2013/ABI 2728).Peer reviewe

Coffee silverskin extract: Nutritional value, safety and effect on key biological functions

This study aimed to complete the scientific basis for the validation of a coffee silverskin extract (CSE) as a novel food ingredient according to European legislation. Nutritional value, safety, effects on biochemical biomarkers and excretion of short chain fatty acids (SCFAs) in vivo of CSE were assessed. Proteins, amino acids, fat, fatty acids, fiber, simple sugars and micronutrients were analyzed. For the first time, toxicological and physiological effects were evaluated in vivo by a repeated-dose study in healthy Wistar rats. Hormone secretion, antioxidant (enzymatic and no-enzymatic) and anti-inflammatory biomarkers, and dietary fiber fermentability of CSE (analysis of SCFAs in feces) were studied in biological samples. This unique research confirms the feasibility of CSE as a human dietary supplement with several nutrition claims: “source of proteins (16%), potassium, magnesium, calcium and vitamin C, low in fat (0.44%) and high in fiber (22%)”. This is the first report demonstrating that its oral administration (1 g/kg) for 28 days is innocuous. Hormone secretion, antioxidant or anti-inflammatory biomarkers were not affected in heathy animals. Total SCFAs derived from CSE fiber fermentation were significantly higher (p < 0.05) in male treated rats compared to male control rats. All the new information pinpoints CSE as a natural, sustainable and safe food ingredient containing fermentable fiber able to produce SCFAs with beneficial effects on gut microbiota.The SUSCOFFEE Project (AGL2014-57239-R): Sustainable coffee production and consumption: Valorization of coffee waste into food ingredients funded this work. A. Iriondo-DeHond is a fellow of the FPI predoctoral program of MINECO (BES-2015-072191).Peer reviewe

Validation of coffee by-products as novel food ingredients

This research aimed to validate coffee husk, parchment and silverskin as new health-promoting food ingredients. Characterization of the novel ingredients was carried out by Raman and infrared spectroscopy and analysis of total phenolic compounds, chlorogenic acid, caffeine and dietary fiber. Antioxidant properties of the novel ingredients were tested by ABTS and intracellular ROS formation in HepG2 cells. Pesticides, mycotoxins, acrylamide and acute toxicity experiments following OECD Test Guidelines 425 were performed to assess the food safety of extracts, solid residues and raw materials. Husk and silverskin are proposed as a source of two food ingredients: aqueous extracts enriched in phytochemicals and antioxidant dietary fiber while parchment is proposed as a natural source of antioxidant dietary fiber. No lesions were found in selected isolated vital organs from treated animals. Coffee by-products can be converted into safe food ingredients allowing a whole food waste recovery. Analyses of contaminants are essential for achieving this goal.The SUSCOFFEE Project (AGL2014-57239-R): “Sustainable coffee production and consumption: Valorization of coffee waste into food ingredients” funded this work. A. Iriondo-DeHond is a fellow of the FPI predoctoral program of MINECO (BES-2015-072191).Peer reviewe

Food waste recovery for health sustainability. Coffee case

Resumen del trabajo presentado a la 5th International ISEKI_Food Conference: "The food system approach: new challenges for education, research and industry", celebrada en Stuttgart (Alemania) del 3 al 5 de julio de 2018.Very recently, the term "sustainable health" was coined as "a healthy and active ageing avoiding the risk of diseases". The goal may be accomplished by delivering high quality care and improved public health without exhausting natural resources or causing severe ecological damage. Bioactive compounds with health promoting properties can be obtained by food waste recovery. The present research aimed to validate coffee by-products (husk, parchment and silverskin) as health-promoting food ingredients by recycling the complete by-product avoiding the generation of new wastes. Aqueous extracts from coffee by-products were obtained according to WO2013004873A1. Pesticides, mycotoxins, acrylamide, microorganisms and acute toxicity experiment following OECD Test Guidelines 425 were performed for assessing food safety of extracts, solid residues and raw materials. Chemical characterization of the novel ingredients was carried out by raman and infrared spectroscopy and analysis of total phenolic compounds, chlorogenic acid, caffeine and dietary fiber. Antioxidant properties of the novel ingredients were tested by ABTS and intracellular ROS formation in HepG2. Aqueous extracts from coffee by-products showed high phenolic content (15.58 - 68.21 mg chlorogenic acid (CGA) eq./g) and antioxidant capacity (80.6 - 202.16 mg CGA eq./g). Robusta silverskin extract presented the highest content of CGA (21.3 mg/g) and parchment extract the highest values for caffeine (58.18 mg/g). The extracts were not cytotoxic at the concentrations tested (0.1 - 1 mg/ml) and reduced physiological reactive oxygen species in HepG2 cells. Insoluble fractions contained high values of total dietary fiber (husk, 71.9 %; parchment, 91.56 %; Arabica and Robusta silverskin, 67.69 % and 69.33 %). No lesions were found on examination of selected isolated vital organs from testing animals. In conclusion, husk and silverskin are proposed as sources of two food ingredients: aqueous extracts enriched in phytochemicals and antioxidant dietary fiber; while parchment as a single source of antioxidant dietary fiber. Coffee by-products can be converted into health-promoting food ingredients for a sustainable health allowing a whole food waste recovery.This work was funded by the SUSCOFFEE Project (AGL2014-57239-R).Peer Reviewe

Bioaccesibility, metabolism, and excretion of lipids composing spent coffee grounds

This article belongs to the Special Issue Dietary Lipids and Human Health.The bioaccessibility, metabolism, and excretion of lipids composing spent coffee grounds (SCGs) were investigated. An analysis of mycotoxins and an acute toxicity study in rats were performed for safety evaluation. Total fat, fatty acids, and diterpenes (cafestol and kahweol) were determined in SCGs and their digests obtained in vitro. A pilot repeated intake study was carried out in Wistar rats using a dose of 1 g SCGs/kg b.w. for 28 days. Fat metabolism was evaluated by analysis of total fat, cholesterol, and histology in liver. The dietary fiber effect of SCGs was measured radiographically. The absence of mycotoxins and toxicity was reported in SCGs. A total of 77% of unsaturated fatty acids and low amounts of kahweol (7.09 µg/g) and cafestol (414.39 µg/g) were bioaccessible after in vitro digestion. A significantly lower (p < 0.1) accumulation of lipids in the liver and a higher excretion of these in feces was found in rats treated with SCGs for 28 days. No lipid droplets or liver damage were observed by histology. SCGs acutely accelerated intestinal motility in rats. SCGs might be considered a sustainable, safe, and healthy food ingredient with potential for preventing hepatic steatosis due to their effect as dietary fiber with a high fat-holding capacity.This research was funded by the SUSCOFFEE (AGL2014-57239-R) Project.Peer reviewe