Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part II: Breads Not Containing Oil as an Ingredient

Nutrient Composition, Physical Characteristics and Sensory Quality of Spinach-Enriched Wheat Bread

Food innovation that utilises agricultural waste while enhancing nutritional value is important for waste valorisation and consumer health. This study investigated incorporating spinach (Spinacia oleracea), as a model leafy agricultural waste, into wheat bread. We analysed the nutrient content, colour, texture, sensory attributes and purchase/consume intention ratings. Adding 10-40% spinach (w/w) yielded loaves with similar heights but significantly different colour and texture (p < 0.05) from white bread. Increasing spinach decreased total carbohydrates (including starch) while significantly increasing other nutrients (protein, fibre, iron, magnesium, potassium, zinc, calcium, vitamins A, C, E, folate, niacin, pyridoxine, nitrate/nitrite and polyphenols) (p < 0.05). Spinach addition increased bread porosity, linked to higher pasting parameters (peak, trough, breakdown, final and setback viscosity) with reduced pasting time and temperature. Texture analysis resulted in decreased hardness, chewiness, gumminess and firmness while increasing cohesiveness, with maximum resilience at 20% spinach enrichment. Sensory analysis with 21 untrained panellists revealed decreased visual appeal, less preferred taste, odour and overall liking (p < 0.05) with increasing spinach, with no significant difference in texture acceptance, but the 20% enrichment had comparable acceptance to white bread. Enriching staple foods like bread with leafy vegetable waste offers a promising approach for increasing daily vegetable intake.

Exploring consumer beliefs about novel fortified foods: A focus group study with UK-based older and younger adult consumers

Consuming 'nutritionally-enhanced' food products (including those that are fortified or enriched to deliver nutritional and functional properties) may help to improve overall diet quality and combat risks associated with malnutrition. However, fortification can negatively impact consumer acceptance, particularly where expected sensory properties of 'delivery' foods are affected by target ingredients. Here, we explored factors influencing consumer acceptability for six novel food products that had been fortified, including both savoury and sweet meal components (e.g., high protein dumplings, probiotic yoghurt drink). In person focus groups (25 consumers aged between 22 and 76 years old) were conducted with two stages; firstly, participants completed a blind taste test of products without awareness of fortification. Secondly, participants discussed products with awareness of additional ingredients and food properties. Reflexive thematic analysis showed that liking of sensory properties differed between foods, but informing participants about the fortification of products highlighted potential trade-offs between taste, health, price, and familiarity. Though taste and texture were generally prioritised by participants, positive perceptions of health benefits increased consumer willingness to buy, whilst both cost and uncertainty about product use were potential barriers. Trust of information was a key concern for labelling and product claims. These results highlight product features that may be optimised to support the success of fortified foods. Greater transparency when building product brands and improving consumer knowledge of fortification may also be important for longer-term consumer acceptance.

Vegetable-enriched bread: Pilot and feasibility study of measurement of changes in skin carotenoid concentrations by reflection spectroscopy as a biomarker of vegetable intake

Globally, bread is a staple food and thus a promising vehicle for the delivery of nutrients from vegetables including carotenoids. The aim of this pilot/feasibility, pre-post experimental study was to measure skin (Veggie Meter™) and plasma carotenoid concentrations 1 week before (week -1), immediately prior to (week 0), and after (week 2) 14 days of daily consumption of 200 g pumpkin- and sweetcorn-enriched bread (VB). At each measurement point, total vegetable and fruit intake and specific carotenoid-rich foods were assessed by questionnaire. Participants (n = 10, 8 males, 2 females) were aged between 19 and 39 years and weighed 90 ± 20 kg. Vegetable and fruit intake was low and less than one serving/day of foods containing carotenoids. Prior to the intervention, measures of carotenoid-containing foods and skin or plasma carotenoids were not different when measured a week apart. Consumption of the VB did not result in statistically significant changes in either the skin or plasma carotenoid measurements. Plasma carotenoid concentrations and the carotenoid reflection scores had a large and positive (r = .845, 95% CI 0.697, 0.924) association. The relationship between the number of servings of carotenoid-rich foods with the plasma carotenoid and carotenoid reflection scores was positive and of moderate strength. In conclusion, carotenoid status was not measurably changed with the consumption of 200 g VB each day for 2 weeks. Subjective carotenoid-rich food intake was positively associated with objective biomarkers of carotenoids. The Veggie meter™ has the potential to provide portable measurement of circulating carotenoids and be indicative of intake of carotenoid-rich foods.

Biocolorants in food: Sources, extraction, applications and future prospects

Color of a food is one of the major factors influencing its acceptance by consumers. At presently synthetic dyes are the most commonly used food colorant in food industry by providing more esthetically appearance and as a means to quality control. However, the growing concern about health and environmental due to associated toxicity with synthetic food colorants has accelerated the global efforts to replace them with safer and healthy food colorants obtained from natural resources (plants, microorganisms, and animals). Further, many of these biocolorants not only provide myriad of colors to the food but also exert biological properties, thus they can be used as nutraceuticals in foods and beverages. In order to understand the importance of nature-derived pigments as food colorants, this review provides a thorough discussion on the natural origin of food colorants. Following this, different extraction methods for isolating biocolorants from plants and microbes were also discussed. Many of these biocolorants not only provide color, but also have many health promoting properties, for this reason their physicochemical and biological properties were also reviewed. Finally, current trends on the use of biocolorants in foods, and the challenges faced by the biocolorants in their effective utilization by food industry and possible solutions to these challenges were discussed.

Effect of Tomato, Beetroot and Carrot Juice Addition on Physicochemical, Antioxidant and Texture Properties of Wheat Bread

Bakery products, including bread, are important components of the diet of people all over the world. One of the food industry's goals is to improve its quality in the context of healthiness and physical parameters. Consumers' perception of sensory quality is an important aspect of food choice. Thus, the study aimed to enhance nutritional parameters (antioxidant capacity, content of phenolic compounds) together with maintaining or increasing bread quality (texture, color, volume and sensory properties). Among vegetable juices, tomato, beetroot and carrot were selected, as they are easily accessible in Europe and are inexpensive. At the same time, those juices are known to be high in antioxidants. In this study, the effect of substituting recipe water with tomato, beetroot and carrot juices (replacement level: 15, 30, 50% v/v) was evaluated in terms of the specific volume, texture, color, acidity, polyphenol contents, antioxidant and sensory properties. It was concluded that juice content had a significant positive impact on physicochemical parameters such as volume, color, acidity, as well as the antioxidant activity of breads. The carrot and beetroot juices were the most efficient in terms of shaping wheat bread properties, especially in terms of antioxidant activity.

Bioactive Properties of Bread Formulated with Plant-based Functional Ingredients Before Consumption and Possible Links with Health Outcomes After Consumption- A Review

Bread is a commonly consumed staple and could be a viable medium to deliver plant-based ingredients that demonstrate health effects. This review brings together published evidence on the bioactive properties of bread formulated with plant-based ingredients. Health effects associated with the consumption of bread formulated with plant-based functional ingredients was also reviewed. Bioactive properties demonstrated by the functional ingredients fruits and vegetables, legumes, nuts and tea incorporated into bread include increased phenolic and polyphenolic content, increased antioxidant activity, and extension of bread shelf-life by impairment of lipid and protein oxidation. Acute health effects reported included appetite suppression, reduced diastolic blood pressure, improvements in glycaemia, insulinaemia and satiety effect. These metabolic effects are mainly short lived and not enough for a health claim. Longer term studies or comparison of those who consume and those who do not are needed. The incorporation of plant-based functional ingredients in bread could enhance the health-promoting effects of bread.

Valorisation of Broccoli By-Products: Technological, Sensory and Flavour Properties of Durum Pasta Fortified with Broccoli Leaf Powder

The aim of this study was to evaluate the effect of broccoli leaf powder (BLP) incorporation on the technological properties, sensory quality and volatile organic compounds (VOCs) of durum wheat pasta. Incorporation of BLP increased cooking loss; however, all pasta samples were found to be in the acceptable range of 8 g/100 g. The addition of BLP decreased optimal cooking time and water absorption but increased the swelling index. Firmness and total shearing force decreased with increased BLP content. The obtained pasta was greener than the control, with a higher content of minerals, and an increasing tendency with respect to protein was observed. The VOC profile of enriched pasta was richer and contained compounds typical of broccoli (e.g., dimethyl sulphide), affecting its aroma. The sensory evaluation results indicate that the addition of BLP did not affect the overall acceptance of pasta. Up to 5% BLP content afforded an interesting, more nutritious pasta without compromising its technological and sensory quality.

Beetroot as a novel ingredient for its versatile food applications

Beta vulgaris, also known as Beetroot, is a member of a family of Chenopodiaceae and is widely used as a natural food colorant. It gets its distinctive color due to nitrogen-containing water-soluble pigments betalains. Beetroot is an exquisite cradle of nutrients, including proteins, sucrose, carbohydrates, vitamins (B complex and vitamin C), minerals, fiber. They also contain an appreciable amount of phenolic compounds and antioxidants such as coumarins, carotenoids, sesquiterpenoids, triterpenes, flavonoids (astragalin, tiliroside, rhamnocitrin, kaempferol, rhamnetin). Recent studies evidenced that beetroot consumption had favorable physiological benefits, leading to improved cardiovascular diseases, hypertension, diabetes, cancer, hepatic steatosis, liver damage, etc. This review gives insights into developing beetroot as a potential and novel ingredient for versatile food applications and the latest research conducted worldwide. The phytochemical diversity of beetroot makes them potential sources of nutraceutical compounds from which functional foods can be obtained. The article aimed to comprehensively collate some of the vital information published on beetroot incurred in the agri-food sector and a comprehensive review detailing the potentiality of tapping bioactive compounds in the entire agriculture-based food sector.

Incorporation of polyphenols in baked products

Bakery foods, including breads, cakes, cookies, muffins, rolls, buns, crumpets, pancakes, doughnuts, waffles, and bagels, etc., have been an important diet of humans for thousands of years. As the nutraceuticals with various biological activities, polyphenols, especially polyphenol-enriched products are widely used in bakery foods. The polyphenol-enriched products are mainly from fruits and vegetables, including fruits in whole, juice, puree, jam, and the powder of dried fruits, pomace, and peels. Incorporation of these products not only provide polyphenols, but also supply other nutrients, especially dietary fibers for bakery products. This chapter discussed the thermal stability of different types of polyphenols during baking, and the effect of polyphenols on the sensory attributes of baked foods. Moreover, their role in mitigation of reactive carbonyl species and the subsequent formation of advanced glycation end products, antioxidant and antimicrobial activities have been also discussed. Since polyphenols are subjected to high temperature for dozens of minutes during baking, future works need to focus on the chemical interactions of polyphenols and their oxidized products (quinones) with other food components, and the safety consequence of these interactions.

Application of Broccoli Leaf Powder in Gluten-Free Bread: An Innovative Approach to Improve Its Bioactive Potential and Technological Quality

In comparison to conventional bread, gluten-free bread (GF) shows many post-baking defects and a lower nutritional and functional value. Although broccoli leaves are perceived as waste products, they are characterised by a high content of nutrients and bioactive compounds. The present study evaluated the nutritional value, technological quality, antioxidant properties, and inhibitory activity against the formation of advanced glycation end-products (AGEs) of GF enriched with broccoli leaf powder (BLP). Compared to the control, gluten-free bread with BLP (GFB) was characterised by a significantly (p < 0.05) higher content of nutrients (proteins and minerals), as well as improved specific volume and bake loss. However, what needs to be emphasised is that BLP significantly (p < 0.05) improved the antioxidant potential and anti-AGE activity of GFB. The obtained results indicate that BLP can be successfully used as a component of gluten-free baked products. In conclusion, the newly developed GFB with improved technological and functional properties is an added-value bakery product that could provide health benefits to subjects on a gluten-free diet.

Side Streams of Broccoli Leaves: A Climate Smart and Healthy Food Ingredient

Human consumption of fruits and vegetables are generally below recommended levels. Waste from the production, e.g., of un-used parts such as broccoli leaves and stem when producing broccoli florets for food, is a sustainability issue. In this study, broccoli leaves were analyzed for the content of various dietary fibre and phenolics, applying the Uppsala method and HPLC analyses, respectively. The results showed that broccoli leaves had comparable levels of dietary fibre (26%-32% of dry weight (DW)) and phenolic compounds (6.3-15.2 mg/g DW) to many other food and vegetables considered valuable in the human diet from a health perspective. A significant positive correlation was found among soluble dietary fibre and phenolic acids indicating possible bindings between these components. Seasonal variations affected mainly the content of conjugated phenolics, and the content of insoluble dietary fibre. This study verified the importance of the use of broccoli production side streams (leaves) as they may contribute with health promoting components to the human diet and also socio-economic and environmental benefits to the bioeconomic development in the society.

Vicia faba hull: A novel source of fibre, and a functional food with antidiabetic properties

Combinable broad beans (Vicia faba) is a major agricultural crop in Europe with annual production around 1.5 million mt. During its milling the seed testa (hull) is removed and is a significant underutilised secondary product. The aim of this study was to examine the nutritional and functional properties of broad bean hull (BBH), specifically for blood glucose control and as a source of fibre for humans.

The proximate composition of BBH was assessed using standard AOAC methods and the phytochemical profile using LC-MS(1). BBH extracts were characterised for total polyphenol content, antioxidant potential (FRAP, TEAC)(2), and effects on α-amylase (AA) and α-glucosidase (AG) enzyme activity(3). Bread containing BBH was developed and assessed for glycaemic potential using a standardised in vitro gastro-intestinal digestion model(4). Wheat bran and acarbose were used as comparators.

BBH showed a comparable proximate composition to wheat bran but with higher fibre (49 vs 43 g/100g), and lower carbohydrate (19 vs 23 g/100g) and fat contents (1.3 vs 5 g/100g). LC-MS profiling showed that proanthocyanidins were the predominant phytochemicals in the hull with some minor compounds including flavonols. Total polyphenol content and antioxidant potential (FRAP, TEAC) of BBH was significantly higher than in wheat bran (160.1 vs 12.3 μg Gallic acid/mL, 3877.9 vs 75.5 μM Fe Sulphate, and 0.50 vs 0.19 mM Trolox Eq respectively; P < 0.001). Compared to acarbose BBH showed a significantly higher IC50 for α-amylase inhibition (76.6 vs 4.2 μg/mL), and a significantly lower value for α-glucosidase inhibition (2.7 vs 2175.8 μg/mL)(P < 0.001). The addition of BBH significantly reduced starch digestion in bread during the oral, gastric phases and at 20 and 60 min of intestinal digestion (P < 0.005).

Broad bean hull is a good source of non-soluble fibre with potential for increasing fibre contents in foods by up to 15g/100 g. Compared to similar material it is a richer source of polyphenols and antioxidants, retards both α-amylase and α-glucosidase activity and shows potential for reducing the glycaemic potential of foods.

The work was funded by the Rural and Environment Science and Analytical Services Division of the Scottish government (RESAS).

Cinnamon Shows Antidiabetic Properties that Are Species-Specific: Effects on Enzyme Activity Inhibition and Starch Digestion

Despite considerable research the evidence around the antidiabetic properties of cinnamon remains equivocal, and this may be due to varietal differences which is an aspect that is understudied. This study systematically compared the anti-hyperglycaemic properties of the four major commercial cinnamon types used around the world (Chinese; Cinnamomum cassia [CC], Indonesian; C. burmanii [IC], Vietnamese; C. loureirii [VC], and Ceylon; C. zeylanicum [SC]). LC-MS analysis showed distinct diffrences in the phytochemical profiles of cinnamon with SC showing the lowest coumarin concentration. CC and IC had the highest polyphenol levels and antioxidant potential, and all four types differed significantly in their content (P < 0.001). All cinnamon types showed potent species-specific effects on starch digestion enzyme activity inhibition (P < 0.001), CC was most effective against α-amylase and all four strongly inhibited α-glucosidase compared to acarbose. Cinnamon significantly reduced starch breakdown during oral (P = 0.006) and gastric (P = 0.029) phases of gastro-intestinal digestion with IC and SC showing consistent effects. No effects of cinnamon were seen in the intestinal phase. IC, VC and SC showed the greatest potential to inhibit formation of advanced glycation endproducts (AGEs) during digestion. In conclusion, cinnamon demonstrates anti-hyperglycaemic properties, however effects are species-specific with best overall properties seen for Ceylon cinnamon.

Bread Enriched With Legume Microgreens and Leaves-Ontogenetic and Baking-Driven Changes in the Profile of Secondary Plant Metabolites

Flavonoids, carotenoids, and chlorophylls were characterized in microgreens and leaves of pea (Pisum sativum) and lupin (Lupinus angustifolius) as these metabolites change during ontogeny. All metabolites were higher in the leaves for both species. Acylated quercetin and kaempferol sophorotrioses were predominant in pea. Genistein and malonylated chrysoeriol were predominant in lupin. Further, the impact of breadmaking on these metabolites using pea and lupin material of two ontogenetic stages as an added ingredient in wheat-based bread was assessed. In "pea microgreen bread" no decrease of quercetin was found with regard to the non-processed plant material. However kaempferol glycosides showed slight decreases induced by the breadmaking process in "pea microgreen bread" and "pea leaf bread." In "lupin microgreen bread" no decrease of genistein compared to the non-processed plant material was found. Chrysoeriol glycosides showed slight decreases induced by the breadmaking process in "lupin microgreen bread" and "lupin leaf bread." In all breads, carotenoids and chlorophylls were depleted however pheophytin formation was caused. Thus, pea and lupin microgreens and leaves are suitable, natural ingredients for enhancing health-promoting secondary plant metabolites in bread and may even be used to tailor bread for specific consumer health needs.

Polyphenol composition and antioxidant properties of vegetable leaf-fortified bread

The aim of this work was to determine the antioxidant properties of aqueous extracts of vegetable leaf-fortified bread as well as estimate the contents of polyphenolic compounds. Enriched bread was produced from wheat flour fortified at 1, 2, and 3% (w/w) with dried leafy vegetable powders from Amaranthus viridis, Solanum macrocarpon, and Telfairia occidentalis. Gallic acid was the most abundant soluble polyphenol in the control bread and the content in the control bread was significantly higher (p < 0.05) than in all the fortified bread samples. Fortification of bread especially at 3% level resulted in significantly (p < 0.05) higher concentrations of other polyphenols (myricetin, catechin, quercetin, and rutin) compared to the control bread. The fortified bread extracts had significantly (p < 0.05) more effective antioxidants than the control for DPPH radical scavenging activity, ferric iron reducing antioxidant power, metal chelation, and inhibition of linoleic acid peroxidation. PRACTICAL APPLICATIONS: Bread is one of the consumed foods and could be used as a suitable carrier of bioactive compounds. Leafy vegetables contain high levels of polyphenols that could provide beneficial effects by contributing to improved health status of consumers. Therefore, incorporation of leafy vegetables into leavened bread could provide a means of enhancing polyphenol consumption. In this work, we showed that soluble polyphenols were enriched in vegetable-fortified bread. The polyphenol-rich extracts of the fortified bread demonstrated better free radical scavenging and inhibition of unsaturated fatty acid oxidation activities than the regular bread. Therefore, regular consumption of vegetable leaf-fortified bread could lead to reduced oxidative stress and associated chronic diseases in human beings. The vegetable leaf fortification could also serve as a suitable means of enhancing the shelf life of wheat bread.

Beetroot improves oxidative stability and functional properties of processed foods: singular and combined effects with chocolate

Oxidation is a significant problem in processed foods affecting their physico-chemical, shelf life and health properties. Natural antioxidants could be viable alternatives to synthetic variants for safely improving antioxidation properties of processed foods. The aim of this study was to assess the singular and combined effects of beetroot and chocolate on the oxidative stability of a high fat and protein processed food (sponge cake) during storage and gastrointestinal digestion. Cakes were prepared and assessed for antioxidant potential, polyphenols, and oxidative stability, and macronutrient oxidation during simulated gastro-intestinal digestion. Beetroot significantly improved the antioxidant and polyphenol profiles of sponge cake which further improved with chocolate addition. Beetroot also significantly increased the oxidative stability and shelf-life of sponge cake, and these effects were enhanced when combined with chocolate. Chocolate significantly reduced lipid oxidation during the gastric phase of digestion. However, both chocolate and beetroot did not curtail lipid oxidation in the intestinal phase, nor protein oxidation at any of the phases. Promisingly, beetroot and chocolate addition did not affect textural parameters and delayed staling by up to 2 days. Overall, the benefits of beetroot and chocolate addition were manifested more in the food system than during its digestion. Beetroot improves the oxidative stability and shelf life of processed foods, and its effects could be enhanced through combining with other natural products.