Vassilios Raikos

Health-promoting properties of bioactive peptides derived from milk proteins in infant food: a review

Milk proteins have attracted extensive interest in terms of their bioavailability following ingestion. Enzymatic digestion of dairy products generates numerous peptides with various biological activities. Both human milk and infant formulas based on cows milk are potential sources of bioactive peptides. This review aims to present current knowledge on the formation and fate of bioactive peptides from milk feeds intended for infants. Emphasis is placed on the source of the bioactive peptides with the nutritional impact of human milk and cow milk-based formulas on infant health being critically discussed from that perspective. Furthermore, the effect of processing and in vitro or in vivo digestion on the release and availability of peptides with bioactive sequences is evaluated. Considerable differences with respect to bioavailability and metabolic effects between the biologically active fragments generated following ingestion of human milk and infant formulas are documented. Peptides from milk protein of bovine origin could be a valuable supplement to human milk as multiple health-promoting properties are attributed to peptide fractions identified in standard cow milk-based infant formulas.

Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part 1: Breads Containing Oil as an Ingredient

There is increasing emphasis on reformulating processed foods to make them healthier. This study for the first time comprehensively investigated the effects of fortifying bread (containing oil as an ingredient) with freeze-dried vegetables on its nutritional and physico-chemical attributes. Breads fortified with carrot, tomato, beetroot or broccoli were assessed for nutrition, antioxidant potential, storage life, shelf stability, textural changes and macronutrient oxidation. Furthermore, using an in vitro model the study for the first time examined the impact of vegetable addition on the oxidative stability of macronutrients during human gastro-intestinal digestion. As expected, adding vegetables improved the nutritional and antioxidant properties of bread. Beetroot and broccoli significantly improved bread storage life. None of the vegetables significantly affected bread textural changes during storage compared to the control. Lipid oxidation in fresh bread was significantly reduced by all four types of vegetables whilst protein oxidation was lowered by beetroot, carrot and broccoli. The vegetables demonstrated varying effects on macronutrient oxidation during gastro-intestinal digestion. Beetroot consistently showed positive effects suggesting its addition to bread could be particularly beneficial.

Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH

The demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4–10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment.

Use of β-glucan from spent brewer's yeast as a thickener in skimmed yogurt: Physicochemical, textural, and structural properties related to sensory perception

Powdered β-glucan extracted from brewers yeast (Yestimun, Leiber GmbH, Bramsche, Germany) was incorporated into skimmed-milk yogurt at varying concentrations (0.2-0.8% wt/wt) to investigate its potential application as a thickener. The effect of β-glucan fortification on the nutritional profile, microstructure, physicochemical properties, and texture of freshly prepared yogurts was investigated. Sensory evaluation was also conducted and was correlated with instrumental analysis. The addition of Yestimun significantly reduced the fermentation time of the yogurt mix from 4 h to 3 h. Scanning electron microscopy revealed that β-glucan particles formed small spherical clusters within the yogurt matrix. The majority of the physicochemical properties (syneresis, viscosity, color, and titratable acidity) remained unaffected by the incorporation of Yestimun in the recipe. Textural properties showed a gradual increment with increasing β-glucan concentration. Hardness, total work done, adhesive force, and adhesiveness increased by 19.27, 23.3, 21.53, and 20.76%, respectively, when using the highest amount of Yestimun powder. Sensory analysis (n = 40) indicated that fortifying yogurt with Yestimun at 0.8% (wt/wt) concentration may affect overall acceptance ratings, which was attributed to adverse flavor and aftertaste effects. However, the overall liking score of the yogurt (5.0/9.0) shows potential for commercialization of the product.

Formulating orange oil-in-water beverage emulsions for effective delivery of bioactives: Improvements in chemical stability, antioxidant activity and gastrointestinal fate of lycopene using carrier oils

The influence of carrier oil type on the chemical stability, antioxidant properties and bioaccessibility of lycopene in orange oil-in-water beverage emulsions was investigated. The emulsions were formulated with orange oil (A), which was partially (50%) replaced with tributyrin (B) or corn oil (C) because of their distinctively different fatty acid composition. The addition of corn oil enhanced the physical stability of the beverage during chilled storage by inhibiting Ostwald ripening. The formation of oxidation products was insignificant after storage for 28 days at 4 °C, regardless the type of added oil. Lycopene was more susceptible to chemical degradation in the presence of unsaturated, long chain triglycerides and the retention followed the order: A (87.94%), B (64.41%) and C (57.39%). Interestingly, bioaccessibility of lycopene was significantly lower for emulsions formulated with 50% corn oil as opposed to 100% orange oil as indicated by the simulated in vitro gastric digestion model.

Formulating orange oil-in-water beverage emulsions for effective delivery of bioactives: Influence of carrier oil type on chemical stability, antioxidant activity and in vitro bioaccessibility of lycopene

T carotenoids inclusion in diet is considered to contribute to human health, as their antioxidant properties are associated with a reduced risk for the development of chronic diseases. Thus, the consumption of lycopene, which is the most predominant carotenoid in human plasma, is important for various biological functions. The addition of lycopene in food formulations is problematic because of its lipophilic nature and high susceptibility to oxidation. However, its bioavailability can increase when co-ingested with other lipids. A popular method for increasing carotenoid bioavailability is emulsification. The purpose of the present work was to develop an edible orange oil-in-water beverage emulsion containing lycopene as a bioactive ingredient. Particularly, the influence of carrier oil type on the chemical stability, antioxidant properties and bioaccessibility of lycopene in orange oil-in-water beverage emulsions was investigated. The emulsions were formulated with orange oil (A), which was partially (50%) replaced with tributyrin (B) or corn oil (C). The addition of corn oil enhanced the physical stability of the beverage during chilled storage by inhibiting Ostwald ripening. The formation of oxidation products was insignificant during storage for 28 days at 4°C, regardless the type of added oil. Lycopene was more susceptible to chemical degradation in the presence of unsaturated, long chain triglycerides and the retention followed the order: A (87.94%), B (64.41%) and C (57.39%). Interestingly, bioaccessibility of lycopene was significantly lower for emulsions formulated with 50% corn oil as opposed to 100% orange oil as indicated by the simulated in vitro gastric digestion model.

Rosemary powder filtrate improves the oxidative stability and antioxidant properties of rapeseed oil: potential applications for domestic cooking

The authors would like to thank the Gen Foundation (London, UK) for providing funding to support this research.

Incorporating salal berry (Gaultheria shallon) and blackcurrant (Ribes nigrum) pomace in yogurt for the development of a beverage with antidiabetic properties

In this study aqueous extracts from salal berry (SB) and blackcurrant pomace (BCP) were used to reformulate yogurt and the anti-diabetic properties of the beverage were investigated during 4 weeks of cold storage at 4 °C. Results indicated that α-amylase, α-glucosidase and DPP-IV inhibitory activities increased with storage time for all samples. At the end of storage period α-amylase, α-glucosidase and DPP-IV inhibition were >61%, 62% and 56% respectively for all yogurt types. This increase in bioactivity during cold storage is attributed to the viability of lactic acid bacteria (∼108 cfu/g), which is maintained for 4 weeks. Enzyme inhibition increased similarly for all yogurt types at 4 °C except for α-glucosidase. Yogurt with BCP showed the highest potency to inhibit α-glucosidase (>90%) with an IC50 value of 0.20 mg/ml (week 4). A peptidomic approach based on liquid chromatography coupled with mass spectrometry (LC-MS) was used for the separation and identification of peptides generated in three types of yogurt. A total of 486 peptides mainly from caseins were identified, of which 15 have documented bioactivity, predominantly as antimicrobial agents or ACE-inhibitors.