Influence of ripening stage and de-astringency treatment on the production of dehydrated persimmon snacks.

BACKGROUND: Seasonal persimmon (Diospyros kaki L.) crops have steadily increased in Spain; this has been linked to a significant increase in the postharvest production waste. Therefore, development of valorized products is of great interest. In this study, a hot air-drying technique was used to obtain persimmon snacks. Slices from astringent and non-astringent persimmons (submitted to de-astringency treatment) at three different ripening stages were dried at 40 and 60 °C to reach 15 ± 3% water content. RESULTS: After the drying treatment, dehydrated samples were harder, turned into a more orange hue angle, and had a reduced soluble tannin content. Dehydrated samples obtained from the astringent fruit at the most advanced ripening stage had similar soluble tannin content as the samples obtained from non-astringent fruit, especially at 60 °C. Besides, a high correlation was observed between the level of astringency perceived by consumers and the decrease of soluble tannin content. Although, in the first ripening stage, consumers preferred the snacks obtained from non-astringent fruits; in the last ripening stage, snacks produced from astringent fruits were equally accepted than the non-astringent ones. CONCLUSION: Therefore, well-accepted persimmon snacks are obtained from both astringent and non-astringent fruits when advanced ripening stages of persimmon are used. © 2020 Society of Chemical Industry.

Physicochemical changes and chilling injury disorders in 'Tango' mandarins stored at low temperatures.

BACKGROUND: The susceptibility to chilling injury and quality changes of 'Tango' mandarins stored at different temperatures was evaluated in fruit grown at two locations in Andalusia (Spain) and grafted on Carrizo Citrange or FA5 rootstock. The peel disorders were also characterized by a microstructural study. RESULTS: Fruit developed chilling injuries, manifested as pitting lesions affecting the equatorial area of the fruit stored at 1 °C or 5 °C; fruit growing on FA5 rootstock showed a slightly lower incidence. The microstructural study revealed that only the upper layers of flavedo were affected in the damaged fruit, the epidermal and hypodermal tissues being dramatically collapsed. Although the fruit was prone to accumulate ethanol, especially after the shelf life that followed the different periods of cold storage, the ethanol did not compromise the overall flavor. CONCLUSIONS: Storage of 'Tango' fruit was limited by chilling injuries when stored at 1 °C or 5 °C for more than 20 days. Moreover, at these temperatures, the fruit was prone to accumulate ethanol and develop off flavors. At 9° C, the fruit could be stored for 30 days without compromising external or internal quality. Growing location and rootstock influenced some quality attributes at harvest but not during storage. © 2020 Society of Chemical Industry.

Composition and physicochemical properties of dried berry pomace.

BACKGROUND: Berry pomace is a valuable but little used by-product of juice manufacturing. When processed to a stable fruit powder, the composition differs from that of the whole fruit. To facilitate application in foods, a detailed knowledge of its composition and physicochemical properties is essential. RESULTS: Blackcurrant, redcurrant, chokeberry, rowanberry and gooseberry were selected for analysis. All pomace powders had a high fibre content (> 550 g kg-1 ) and a fat content of up to 200 g kg-1 . Despite identical milling conditions, the particle sizes of the pomace powders varied. This can be traced back to seed content and brittleness, which also becomes apparent with respect to surface characteristics. Blackcurrant pomace powder differed from other varieties in terms of its low water-binding capacity (3.2 g g-1 ) and a moderate moisture uptake, whereas chokeberry pomace powder showed the highest polyphenol content and rowanberry pomace powder was rich in flavonols. CONCLUSION: The results obtained in the present study provide a comprehensive overview of the properties of berry pomace powder and allow conclusions to be made regarding their applicability for use in complex food systems. © 2018 Society of Chemical Industry.

Understanding the effect of emulsifiers on bread aeration during breadmaking.

BACKGROUND: Much research has been done to explain the action of emulsifiers during breadmaking, but there is still plenty unknown to elucidate their functionality despite their diverse chemical structure. The aim of the present study was to provide some light on the role of emulsifiers on air incorporation into the dough and gas bubbles progress during baking and their relationship with bread features. Emulsifiers like diacetyl tartaric acid ester of monoglycerides (DATEM), sodium stearoyl lactylate (SSL), distilled monoglyceride (DMG-45 and DMG-75), lecithin and polyglycerol esters of fatty acids (PGEF) were tested in very hydrated doughs. RESULTS: Emulsifiers increase the maximum dough volume during proofing. Emulsifiers increase the number of bubbles incorporated during mixing, observing higher number of bubbles, particularly with PGEF. Major changes in dough occurred at 70 K when bubble size augmented, becoming more heterogeneous. DMG-75 produced the biggest bubbles. As a consequence, emulsifiers tend to increase the number of gas cells with lower size in the bread crumb, but led to greater crumb firmness, which suggested different interactions between emulsifiers and gluten, affecting protein polymerization during baking. CONCLUSION: The progress of the bubbles during baking allowed the differentiation of emulsifiers, which could explain their performance in breadmaking. © 2018 Society of Chemical Industry.

New hydrocolloid-based emulsions for replacing fat in panna cottas: a structural and sensory study.

BACKGROUND: Dairy desserts are popular traditional products, but because of their high calorie or fat content, they can be unsuitable for people who have certain dietary requirements. The aim of this study was to design panna cottas with similar organoleptic and textural properties to the traditional ones but with a lower fat content, by replacing part of the cream with new emulsions prepared with hydrocolloids (cellulose ethers), namely methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC). RESULTS: Incorporating the MC and HPMC emulsions modified the textural properties (firmness and stiffness) of the panna cottas. Regarding the sensory results, the panna cottas prepared with the MC and HPMC emulsions were considered lumpy and soft respectively. CONCLUSION: Considering the results as a whole, the cellulose type and the amount of cream are factors to take into account. Although the texture and taste of the control panna cotta are better than those of the panna cottas prepared with the MC and HPMC emulsions, it is possible to replace 75% of the cream in traditional panna cottas with HPMC emulsion and obtain good consumer acceptance and purchase intention. The panna cottas with 75% substitution by HPMC emulsion were described as creamy, with smooth appearance and moist mouth feel. © 2017 Society of Chemical Industry.

Cooking methods determine chemical composition and functional properties of squash blossoms: A study of microstructural and bioaccessibility changes.

This research aimed to evaluate the effect of different cooking methods (boiling, stir-frying, and steaming) on the microstructure, moisture, fat, protein, and glucose-derived carbohydrate contents, and the bioactive compounds (total carotenoids: CAR, total chlorophyll: CHLO, and total phenolic compounds: TPC) and antioxidant capacity (AC) of squash blossoms. Furthermore, we characterized polyphenolic compounds using HPLC and evaluated their bioaccessibility via in vitro digestions. Our results show that steaming and boiling do not affect moisture content. Only stir-frying decreased (p < 0.05) this parameter by 8 %. Additionally, the cooking methods increased (p < 0.05) protein and glucose-derived carbohydrate contents. All cooking methods changed the microstructure of the blossoms, probably due to the thermal and mechanical variations that result in moisture loss and degradation of cell wall components. As for the functional properties, boiling caused a greater loss of TPC (up to 96 %) and AC (up to 91 %). Stir-frying caused the greatest loss of CAR (up to 81 %) and CHLO (up to 84 %). The in vitro digestion assays showed changes in the bioaccessibility of CAR, CHLO, TPC, and AC in the cooked flowers compared to the fresh ones. Finally, kaempferol and gallic acid were the most resistant polyphenols to the cooking methods and in vitro digestion.

High pressure homogenization vs heat treatment: safety and functional properties of liquid whole egg.

This research investigated the potential of multi-pass homogenization treatment for the inactivation of Salmonella enterica serovar Enteritidis inoculated at different levels in liquid whole egg (LWE) comparing the efficacy of this treatment with a traditional thermal one performed at 65 °C. Moreover, the effects of high pressure treatment (HPH) on structural and functional properties such as viscosity, microstructure and foaming abilities of LWE were investigated. The data obtained suggested that the multi-pass high pressure treatment at 100 MPa of S. enterica serovar Enteritidis inoculated in LWE at 7 and 4 log CFU/ml resulted in a first order inactivation kinetic, while the thermal inactivation curves of S. enterica serovar Enteritidis inoculated at 8 and 4 log CFU/ml presented a non-linear behaviour, with a marked tail after 3 min of treatment at 65 °C. Additionally, HPH treatment caused an increase in foaming capacity of LWE, with respect to the untreated samples, passing from values of 26% of the control to 50% of pressure treated samples.

Improving Pea Protein Emulsifying Capacity by Glycosylation to Prepare High-Internal-Phase Emulsions.

Pea protein has been extensively studied because of its high nutritional value, low allergenicity, environmental sustainability, and low cost. However, the use of pea protein in some food products is hindered due to the low functionality of pea protein, especially as an emulsifier. High-internal-phase emulsions (HIPEs) are attracting attention because of their potential application in the replacement of hydrogenated plastic fats in foods. In this study, the use of glycated pea protein isolate (PPI) as an emulsifier to prepare HIPEs is proposed. The functionalization of a commercial PPI in two ratios of maltodextrin (MD) (1:1 and 1:2) via glycosylation (15 and 30 min), to act as an emulsifier in HIPEs, is investigated. HIPE properties, such as oil loss and texture, were evaluated and related to microstructural properties. Glycated-PPI-stabilized HIPEs showed high consistency, firmness, viscosity, and cohesiveness values; a tight and homogeneous structure; and physical stability throughout storage. The results showed that emulsions were more stable when using a 1:2 ratio and 30 min of heat treatment. However, the reaction time was more determinant for improving the textural properties when a 1:1 ratio was used for glycosylation than when a 1:2 ratio was used. Glycosylation with MD via the Maillard reaction is a suitable method to enhance the emulsifying and stabilizing properties of PPI.

Incorporating an upcycled orange fibre on flan formulation: Impact on sensory properties.

Fruit by-products are a valuable source of ingredients, in the formulation of what is known by "upcycled foods". Orange pomace, a by-product of orange juice industry, is a dietary fibre source. In this work, a powdered ingredient with soluble fibre obtained from orange pomace was used as replacement of inulin in the formulation of source of fibre "flan" like puddings. Four different formulations were analysed using Flash Profile and instrumental texture: 100% inulin, 70% inulin: 30% orange fibre, 30% inulin: 70% orange fibre, 100% orange fibre. The replacement of 30% of pudding's total fibre with the new ingredient helped to improve the texture and general appearance of the dessert. Greater percentages imparted non-desirable flavour attributes, such as bitterness and acidity. The use of this ingredient as a replacement of commercial inulin in the formulation of source of fibre puddings is possible. However, further research is needed to reduce the off flavours.

Evaluation of the Bioactive Compounds, and Physicochemical and Sensory Properties of Gluten-Free Muffins Enriched with Persimmon 'Rojo Brillante' Flour.

Because of the nutritional need of patients with celiac disease, producing quality gluten-free diet food is important. This study evaluated the use of persimmon flour on the properties of muffins. Persimmon flour obtained from the astringent variety 'Rojo Brillante', which is often discarded due to its characteristic astringency, was added to muffins replacing corn flour (10%, 20%, and 30%). Despite the height differences between the control muffin and the muffins with persimmon flour, similar mechanical parameters were obtained. As the percentage of persimmon flour increased, the muffin color was darker, turning toward a more reddish hue, mainly because of the intensification of nonenzymatic browning reactions. The sensory results showed high scores for taste attributes, the texture attributes were similar to the control, and astringency was hardly detected when persimmon flour was used. The content of tannins and carotenoids and their antioxidant activity increased significantly with an increasing amount of persimmon flour. After in vitro digestion, high recovery index values of soluble tannins and carotenoids were obtained in muffins with added persimmon flour. This study shows that the use of persimmon flour as a functional ingredient offers an opportunity to develop quality gluten-free muffins that reduce agricultural losses. Astringent varieties can be used, without applying a de-astringency treatment, as the astringency is removed during muffin baking due to tannins' insolubilization.

High Internal Phase Emulsions Preparation Using Citrus By-Products as Stabilizers.

The citrus juice industry produces about 50% of by-products. Citrus pomace (CP) contains many polysaccharides (mainly cellulose and pectin), which could act as stabilizers and emulsifiers. The aim of this work was to obtain high internal phase emulsions (HIPEs) using unmodified CP at different concentrations to valorize citrus by-products. The synergic effect of pea protein isolate (PPI) with CP to stabilize the HIPEs was also studied. HIPEs structure was analyzed using rheological and microscopy studies as well as color and physical stability of the emulsions. According to rheological data, all samples exhibited a solid-like behavior, as elastic modulus (G') was higher than viscous modulus (G'') within the viscoelastic linear region; as % CP and % PPI increased, greater values of G' and apparent viscosity (η) were achieved. Microscopic images showed that oil droplets had a polyhedral shape and were enclosed by a thin layer of CP and PPI. Increasing concentrations of CP and PPI enhanced oil droplets packaging. Emulsions' physical stability was better when adding PPI. The results showed that stable HIPEs with 1.25% of CP and PPI over 0.5% can be obtained. These HIPEs could be used to formulate emulsions for food applications, such as mayonnaises, fillings, or creams.

Sorption Isotherms, Glass Transition and Bioactive Compounds of Ingredients Enriched with Soluble Fibre from Orange Pomace.

Citrus fruits are one of the main crops worldwide. Its industrialization, primarily juice production, produces large amounts of byproducts, composed of seeds and peels, that can be used to obtain new ingredients. In this study, sorption behaviour, glass transition, mechanical properties, colour and bioactives of four different soluble fibre-enriched powders obtained from orange pomace using green technologies were studied. Powders were equilibrated at water activities between 0.113 and 0.680 for fifteen weeks at 20 °C, and studies were performed to indicate the best storing conditions to ensure the glassy state of the amorphous matrix and higher bioactive stability. By combining the Gordon and Taylor model with the Henderson isotherm, the critical water activity and content for storage in a glassy state were determined. The ingredient obtained after extrusion + hot water is the most stable, which is also the one with the highest dietary fibre content. Powder obtained by jet cooking is the least stable, as it is not in a glassy state at any water activity at room temperature. To increase storage stability, these should be stored at refrigeration temperatures.

In Vitro and In Vivo Digestion of Persimmon and Derived Products: A Review.

The link between nutrition and health has focused on the strategy of diet-based programs to deal with various physiological threats, such as cardiovascular disease, oxidative stress, and diabetes. Therefore, the consumption of fruits and vegetables as a safeguard for human health is increasingly important. Among fruits, the intake of persimmon is of great interest because several studies have associated its consumption with health benefits due to its high content of bioactive compounds, fiber, minerals, and vitamins. However, during digestion, some changes take place in persimmon nutritional compounds that condition their subsequent use by the human body. In vitro studies indicate different rates of recovery and bioaccessibility depending on the bioactive compound and the matrix in which they are found. In vivo studies show that the pharmacological application of persimmon or its functional components, such as proanthocyanidins, can help to prevent hyperlipidemia and hyperglycemia. Thus, persimmon and persimmon derived products have the potential to be a fruit recommended for diet therapy. This review aims to compile an updated review of the benefits of persimmon and its derived products, focusing on the in vitro and in vivo digestibility of the main nutrients and bioactive compounds.

Interactions between Blackcurrant Polyphenols and Food Macronutrients in Model Systems: In Vitro Digestion Studies.

Blackcurrant pomace, rich in fiber and polyphenols, can be used as added-value ingredient for food formulation. However, the bounding of polyphenols to pomace and the interactions that take place with food nutrients modify polyphenol bioaccessibility. This work studied the interactions between polyphenols and the main macronutrients in foods, and the changes that occurred during in vitro digestion, using model systems. Model systems were formulated with (i) water, (ii) wheat starch, (iii) olive oil, (iv) whey protein, and (v) a model combining all the ingredients. Polyphenols were added from two sources: as pomace and as a polyphenolic pomace extract. Interactions between polyphenols and macronutrients were studied using light microscopy; total phenolic content (TPC) and antioxidant capacity (AC) were determined before and after the in vitro digestion process. Lastly, the bioaccessibility of the samples was calculated. Polyphenols incorporated into the model systems as pomace increased their bioaccessibility if compared to polyphenols added as extract. For single-nutrient model systems formulated with pomace, the bioaccessibility was higher than when the system contained all the nutrients. Of all the components studied, the greatest effect on bioaccessibility was observed for proteins.

Use of Oleogels to Replace Margarine in Steamed and Baked Buns.

Bakery products are usually formulated with solid fats, like margarines and shortenings, which contain high levels of saturated and trans-fatty acids and have negative effects on human health. In this study, hydroxypropyl methylcellulose (HPMC) and xanthan gum (XG) were used as oleogelators to prepare oleogels, using sunflower and olive oil, as substitutes for margarine in baked or steamed buns. The effect of oleogels on the physical properties of the buns was evaluated by analyzing the crumb structure, specific volume, height, and texture. In addition, a triangular discriminatory sensory test was conducted, and lipid digestibility was assessed through in vitro digestion studies. Replacement of margarine with oleogels produced steamed buns with no differences in the crumb structure, volume, height, and texture; however, in baked buns, a less porous and harder structure was produced. No differences in texture were observed between the margarine buns and buns made with oleogels when the triangular test was conducted. The extent of lipolysis was not affected when margarine was replaced by oleogels in the baked and steamed buns. The results suggest that using oleogels instead of margarine in buns could represent an interesting strategy to prepare healthier bakery products.

Providing Stability to High Internal Phase Emulsion Gels Using Brewery Industry By-Products as Stabilizers.

The modern brewing industry generates high amounts of solid wastes containing biopolymers-proteins and polysaccharides-with interesting technological and functional properties. The novelty of this study was to use raw by-product from the brewing industry in the development of high internal phase emulsion (HIPE) gels. Thus, the influence of the emulsion's aqueous phase pH and the by-product's concentration on structural and physical stability of the emulsions was studied. The microstructure was analyzed using cryo-field emission scanning electron microscopy. To evaluate the rheological behavior, oscillatory tests (amplitude and frequency) and flow curves were conducted. Moreover, the physical stability of the emulsions and the color were also studied. The increase in by-product concentration and the pH of the aqueous phase allowed development of HIPE gels with homogeneously distributed oil droplets of regular size and polyhedral structure. The data from the rheology tests showed a more stable structure at higher pH and higher by-product concentration. This study widens the possibilities of valorizing the brewing industry's by-products as stabilizers when designing emulsions.

Ultrasound-assisted acid hydrolysis of cassava (Manihot esculenta) bagasse: Kinetics, acoustic field and structural effects.

Improving the actual acid hydrolysis of cassava bagasse (CB) with the assistance of high-intensity ultrasound (US) was aimed in comparison with mechanical agitation (AG). The kinetics of reducing and total sugar release were mathematically modeled. The acoustic field characterization and apparent viscosity of the suspensions were correlated. Moreover, microscopic analyses (visible, fluorescence and polarized light) were carried out to identify changes produced by the treatments. Both AG and US-treatments showed themselves to be effective at hydrolyzing CB. However, US-experiments reached equilibrium in the reducing sugar release process earlier and obtained slightly higher values of total sugars released. The Naik model fitted the experimental data with good accuracy. A greater loss in the birefringence of the starch granules and the degradation of lignocellulosic matter was also observed in US-assisted hydrolysis. The actual acoustic power applied was reduced after hydrolysis, probably due to the increase in the apparent viscosity of the resulting suspensions.

Effect of pulsed electric fields on carotenoid and phenolic bioaccessibility and their relationship with carrot structure.

Phenolic compounds (PC) and carotenoids from carrots are bound to dietary fibre or stored in vacuoles and chromoplasts, respectively. To exert their antioxidant effects these compounds must be released during digestion, which is hindered by such barriers. Pulsed electric fields (PEF) modify cell membrane permeability, thus enhancing their bioaccessibility. The effect of PEF on the carrot carotenoid and PC content and bioaccessibility was investigated. With this purpose, PEF-treated carrots (5 pulses of 3.5 kV cm-1) were stored for 24 h at 4 °C and microstructure was evaluated before subjecting them to in vitro digestion. PEF did not affect carotenoid content, whereas their bioaccessibility improved (11.9%). Likewise, PEF increased the content of some PC, e.g. coumaric acid (163.2%), probably caused by their better extractability. Conversely, caffeic acid derivatives decreased, which may be associated to greater contact with oxidative enzymes. Total PC bioaccessibility (20.8%) and some derivatives increased, e.g. caffeoylshikimic (68.9%), whereas some decreased (e.g. ferulic acid). Structural changes caused by PEF may improve bioaccessibility of carotenoids and PC by favouring their release and easy access to digestive enzymes. However, other antioxidants may be further degraded or entrapped during digestion. Therefore, PEF is an effective technology for obtaining carrots with enhanced carotenoids and phenolic bioaccessibility.

Optimizing High Pressure Processing Parameters to Produce Milkshakes Using Chokeberry Pomace.

High hydrostatic pressure is a non-thermal treatment of great interest because of its importance for producing food with additional or enhanced benefits above their nutritional value. In the present study, the effect of high hydrostatic pressure processing parameters (200-500 MPa; 1-10 min) is investigated through response surface methodology (RSM) to optimize the treatment conditions, maximizing the phenol content and antioxidant capacity while minimizing microbiological survival, in milkshakes prepared with chokeberry pomace (2.5-10%). The measurement of fluorescence intensity of the samples was used as an indicator of total phenolic content and antioxidant capacity. The results showed that the intensity of the treatments had different effects on the milkshakes. The RSM described that the greatest retention of phenolic compounds and antioxidant capacity with minimum microbiological survival were found at 500 MPa for 10 min and 10% (w/v) chokeberry pomace. Therefore, this study offers the opportunity to develop microbiologically safe novel dairy products of high nutritional quality.

Agave Syrup as an Alternative to Sucrose in Muffins: Impacts on Rheological, Microstructural, Physical, and Sensorial Properties.

Natural sweeteners, such as agave syrup, might be a healthy alternative to sucrose used in sweet bakery products linked to obesity. We evaluated the effect of sucrose replacement by agave syrup on rheological and microstructural properties of muffin batter and on physical and sensorial properties of the baked product. Muffins were formulated by replacing 25%, 50%, 75%, and 100% of sucrose by agave syrup (AS) and partially hydrolyzed agave syrup (PHAS), and by adding xanthan gum and doubled quantities of leavening agents. Rheological and microstructural properties of batter during baking were analyzed over the range of 25-100 °C. In the muffins, the structure, texture, color, and sensory acceptance were studied. The combination of agave syrup with xanthan gum and doubled quantities of leavening agents affected (p < 0.05) rheological and microstructural properties of the batters and textural properties of the low-sucrose muffins compared to the controls. The increase in agave syrup levels resulted in a darker crumb and crust. Sensory evaluation showed that AS-75 and PHAS-75 were the best alternatives to the control samples. Our results suggest a plausible substitution of up to 75% of sucrose by agave syrup in preparation of muffins, with physical and sensorial characteristics similar to those of their sucrose-containing counterparts.