Blueberry Puree Research Articles

Analysis of microwave heating uniformity in berry puree: From electromagnetic-wave dissipation to heat and mass transfer

To understand the non-uniformity of microwave heating, berry puree selected as representative material with high moisture content, movement simulation and beach experiments were employed to analyze the non-uniformity formation and evolution in the blueberry puree loaded in a rectangular container (BLRC) under microwave heating. The results showed that the coupling process via microwave dissipation and heat & mass transfer dominates the uniformity of microwave heating BLRC. The decisively heating modes of microwave dissipation are transverse electric wave and transverse magnetic wave, whose features of microwave dissipation dominate the heat and mass transfer process in BLRC as three distinct stages of temperature changes, including slow elevation then stabilization followed by quick increase. Thermal accumulation, thermal conduction, and latent heat of water vaporization at varying degrees consume microwave dissipation in BLRC. The results provide guidance for understanding microwave heating uniformity and processing technology for agricultural products with similar properties as berry fruit.

Dependence of degradation of anthocyanins on non-uniformity of microwave heating in blueberry puree

To clarify the dependence of anthocyanins degradation on the non-uniformity of microwave heating in blueberry puree, the effects of temperature and moisture content distribution on the content of anthocyanins in blueberry were investigated. The temperature dispersion value (VT), moisture dispersion value (VM), temperature contrast value (CON), the highest temperature (MAX) and hot zone distribution (HTD) were introduced to evaluate the heating uniformity of blueberry puree during microwave heating. The Weibull model can characterize the distribution of anthocyanins content in blueberry puree as the function of the temperature and moisture under microwave heating. The degradation of anthocyanins in blueberry puree has the high dependency on non-uniformity in HTD, MAX, and VT inside blueberry puree under microwave heating. These research results may provide guidance for the quality control of berry products under microwave processing.

Effects of Foaming Treatment and Wave-Absorbing Material-Assisted Microwave Heating on Freeze-Drying of Blueberry Puree

Effects of Foaming Treatment and Wave-Absorbing Material-Assisted Microwave Heating on Freeze-Drying of Blueberry Puree

Relative Cleanability and Sanitization of Blueberry Mechanical Harvester Surfaces

Berry crops are increasingly being harvested mechanically to reduce labor costs, but there is a lack of research on best practices for cleaning and sanitizing of mechanical harvesters to maintain proper food hygiene. Laboratory experiments were conducted with surface coupons cut from materials commonly used on blueberry harvesters, including polyethylene, high-density polyethylene, aluminum, extruded polycarbonate, acetal plastic, and stainless steel. Surfaces differed in their hydrophobicity and surface roughness, ranging from 0.04 µm for polycarbonate to 1.57 µm for acetal plastic. The relative cleanability of the surface coupons was assessed by determining the removal of an applied mock soil (dried blueberry puree) in a rinsing-shaking assay with distilled water at room temperature. Results showed that the amount of soil removed increased over time according to a negative exponential function, from 29.6% at 30 s to 40.3% at 240 s rinse time. Compared with the time effect, the differences in soil removal among surfaces were relatively small. The addition of cleaning agents and detergents did not improve soil removal, and the only treatment that removed significantly more soil than the water control was heated (50 °C) distilled water. In sanitization assays, three representative microorganisms were allowed to attach to surface coupons, then exposed to three different sanitizers (0.25% bleach with 200 ppm free-chlorine sodium hypochlorite, 0.30% SaniDate 5.0, or 1.0% No-Rinse Food Contact Cleaner Sanitizer). There was no significant surface effect on microbial reductions following sanitizer treatment. For Bacillus amyloliquefaciens, none of the sanitizers significantly reduced population densities below the water control. In contrast, surface populations of Rhodoturula mucilaginosa and Epicoccum nigrum were reduced significantly by all three sanitizers, with SaniDate (23.0% hydrogen peroxide + 5.3% peroxyacetic acid) resulting in the greatest reduction.

Influence of fermentation by lactic acid bacteria and in vitro digestion on the biotransformations of blueberry juice phenolics

Enzymes secreted during fermentation by lactic acid bacteria (LAB) may induce structural changes, e.g., promote the transformation of polyphenols in fruits and vegetables and thus influence their bioavailability and antioxidant capacity. This study describes the effects of fermentation by different LAB types (Streptococcus lactis and Pediococcus pentosaceus) and simulated gastrointestinal digestion on the biotransformation and antioxidant capacity of blueberry phenolics, revealing that upon the digestion of fermented samples, antioxidant capacity increases with increasing biotransformation extent because of the concomitant formation of more potent antioxidants. Moreover, the fermentation of blueberry puree increases the bioavailability and bioacceptability of phenolics and thus promotes the survival of LAB after digestion. The best results are obtained for S. lactis, and this LAB type is therefore concluded to hold great promise for the food industry.

BLUEBERRY, SEA BUCKTHORN FRUITS AND APPLE BEVERAGE: BIOCHEMICAL AND SENSORIAL CHARACTERIZATION

This work aimed at optimizing the extraction of total phenolic (TP) and total monomeric anthocyanin (TMA) content for the development of a potentially functional wild blueberry smoothie (BP) with apple puree (AP), apple juice (AJ) and sea buckthorn puree (SBJ) in various proportions using conventional extraction (CE) and advanced extraction techniques [ultrasound-assisted (UAE)]. There were also analyzed the rheological behavior and the color attributes (lightness and redness respectively) of smoothie samples. S7 smoothie sample [30 AP/30 AJ/20 SBJ/20 BP (UAE)] provided a beverage with significant higher amount (21.40%) of anthocyanins (TMA) compared to sample S10 [30 AP/30 AJ/20 SBJ/20 BP (CE)] in which the extraction of anthocyanins was by the classical method. Further, different color attributes, particularly brightness (L *), redness (a *) and yellow (b *) decreased considerably for the samples with 15 and 20% addition of blueberry puree. Therefore, ultrasound-assisted extraction had a significant effect on the amount of anthocyanins extracted, compared to the classical extraction method.

PSVII-12 Acceptability of Milne blueberry juice and blueberry puree in horse feed

Abstract The objective of this study was to evaluate the impact of liquid blueberry juice (BJ65) or blueberry puree (BP30) used as a binding agent on pellet durability and palatability of a typical equine concentrate when included at 4% of the pellet. Molasses was used as a control. Production data, pellet durability and moisture content were evaluated in 1 replicate for each treatment. Because moisture content of condition mashes were 17.59% and 18.11% for BJ65 and BP30 treatments, respectively, greater inclusion of blueberry product would likely cause roller slippage and complicate the pelleting process due to increased liquid (Fahrenholz, 2012). Pellet durability met industry standards for all treatments. Pellets were fed in a 3 x 3 Latin square design to 9 two-year-old horses to determine the effect of blueberry products on acceptability. All animals were allowed 10 minutes to consume 1.36 kg at 0700 h and 1700 h each day for 3 d. Consumption time and amount consumed were recorded to calculate intake, intake rate, and intake ratio (IR). No horse consumed all pellets within the allotted time, and thus, there were no differences between intake rate and intake. Period tended to impact intake (P = 0.0909), with horses consuming less during period 1 than period 3 (P = 0.0317), but period had no effect (P = 0.2881) on IR. Treatment influenced intake (P < 0.0001), with decreased intake of BP30 compared to control and BJ65 (P ≤ 0.0001). Intake ratio was greater (P = 0.0075) for BJ65 than BP30 with IR of 0.5069 and 0.4227, respectively. Consumption of BJ65 was no different than control. Fahrenholz, A. 2012. Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability. Doctoral thesis. Kansas State University, Manhattan, KS.

Effects of high hydrostatic pressure and thermal processing on anthocyanin content, polyphenol oxidase and β-glucosidase activities, color, and antioxidant activities of blueberry (Vaccinium Spp.) puree

Thermal processing (TP) and high hydrostatic pressure (HHP) are two important puree processing methods. In this study, the polyphenol oxidase (PPO) and β-glucosidase activities, chromatic values, peroxide radical scavenging capacities (PSCs), cellular antioxidant activities (CAAs), and anthocyanin profiles were evaluated in blueberry puree following TP and HHP treatments. Nine anthocyanins were identified and cyanidin glycosides were the most abundant compounds in the blueberry puree sample. Petunidin-3-O-arabinoside, malvidin-3-O-galactoside, and malvidin-3-O-glucoside concentrations increased at temperatures of 70–90 °C (TP) and a pressure of 300 MPa (HHP). The highest total anthocyanin concentration (503.5 μg/mL) and PSC (13.45 µg VCE/mL) were observed following the TP (90 °C) treatment. Furthermore, a positive correlation was observed between the anthocyanin content and PSC (R2 = 0.655, P < 0.05). Finally, HHP treatment resulted in better puree color retention than TP treatment. The results of this study could provide valuable information for optimizing the processing methods for anthocyanin-rich products.

Thermal processing under oxygen–free condition of blueberry puree: Effect on anthocyanin, ascorbic acid, antioxidant activity, and enzyme activities

The effect of thermal treatment of blueberry was investigated using a designed grinding and continuous packaging system under oxygen–free conditions. The grinding, packaging, and heating at 90 °C for 30 min under anaerobic condition were compared to heating under aerobic conditions, showing complete inactivation of oxidative enzymes. Heating without oxygen retained anthocyanins and ascorbic acid whereas heating in atmospheric air does not. Delphinidin glycoside was mostly influenced by oxygen deficiency during heating, followed by petunidin and malvidin glycosides. The differences in oxygen sensitivity may be closely associated with the number of hydroxylation in the B ring. The result of anthocyanin led to higher antioxidant activity and redness values of purees heated without oxygen than purees heated with oxygen. Consequently, thermal processing under oxygen–free condition can prevent oxidation of anthocyanin, resulting in higher retention of color and nutritional values of blueberry products.

Stability of blueberry polyphenols subjected to in vitro digestion with human gastrointestinal enzymes

AbstractBlueberries (Vaccinium corymbosum, L.) are a valuable source of health-promoting bioactive compounds, particularly polyphenols. The beneficial effects of polyphenols on health depend not only on food sources but also on their stability, which can vary depending on the post-harvest processing methods, the matrix in which they are incorporated, and endogenous factors such as microbiota and digestive enzymes. The aim of this study was to investigate the influence of high-intensity ultrasound treatment on in vitro gastrointestinal stability of the total polyphenol content and antioxidant capacity of blueberries. Blueberry puree was treated with high-intensity ultrasound using different amplitudes (30, 45 and 60μm) and treatment times (3, 6 and 9 min), and a part of sample was used as a control (untreated sample). Total phenolic content (TPC) and antioxidant capacity (by DPPH and FRAP methods) were determined prior to and after two-phase in vitro digestion process (gastric and duodenal) using human gastrointestinal enzymes. The results showed a high stability of total blueberry polyphenols and antioxidant activity during simulated gastric digestion step, both in untreated and ultrasound treated samples. The use of high-intensity ultrasound had a significant effect on the stability of polyphenols and their antioxidant activity after simulated digestion in duodenum. Significant increase in polyphenol content after duodenal digestion step was determined in three ultrasound treated samples with longer treatment time (6 and 9 minutes), and only sample with significant reduction of TPC was untreated sample. Modification of the food matrix as a result of cavitation from ultrasound treatment may be the reason for higher stability of polyphenol during in vitro digestion. After in vitro digestion blueberry polyphenols still possessed antioxidant activity that may be directly related to their beneficial effects on health. The highest antioxidant activity measured with DPPH and FRAP method was determined for sample treated with maximum amplitude (60μm) and longest time (9 minutes). Determination of the stability of phenolic compounds is important as it affects their bioavailability for uptake as well as their possible beneficial effects on intestinal epithelial tissue such as reduction of oxidative stress and cancer prevention. Our results showed that ultrasound treatment can preserve the blueberry phenolics and their antioxidant characteristics after in vitro digestion.

Study of the interactions between pectin in a blueberry puree and whey proteins: Functionality and application

Protein and fiber, especially pectin, can form complexes at acidic pH. Studies on these complexes under actual food conditions are scarce. The aim of this work was to study interactions between whey proteins and blueberry puree, in particular its pectin, and to evaluate the impact on the functionality of the puree alone or incorporated into a model beverage. After the addition of a whey protein isolate (WPI) into purees at pH 3.5 or 6.5, the soluble pectin and protein contents and the viscosity of the resulting mixtures were determined. The decrease in the solubility of pectin (80%) and proteins (94%) indicated the formation of protein-pectin complexes by electrostatic interactions at pH 3.5, contributing to increase the mixture viscosity. The amount of soluble pectin in blueberry limited the formation of complexes when more WPI was added (5%). Heating the puree prior to the WPI addition solubilized pectin, which limited the formation of insoluble complexes and reduced the viscosity increase. The solubility of the blueberry polyphenols did not decrease after WPI addition. Finally, the non-heated puree enriched in WPI was used to prepare smoothies. This time, the protein-pectin complexation, probably reinforced by the final pasteurization of the smoothies, contributed to reduce the smoothie viscosity and can be explained in particular by particles of smaller sizes. Although the smoothie stability can be improved, the interactions between blueberry pectin in a puree and whey proteins allowed to design a novel functional ingredient that may be helpful in formulating beverages rich in fiber and protein.

Low-Temperature Blanching as a Tool to Modulate the Structure of Pectin in Blueberry Purees.

Blueberry composition was characterized for 6 cultivars. It contains a good amount of dietary fiber (10% to 20%) and pectin (4% to 7%) whose degree of methylation (DM) is sensitive to food processing. A low temperature blanching (LTB: 60 °C/1 h) was applied on blueberry purees to decrease pectin DM, in order to modulate puree properties and functionalities (that is, viscosity and stability), and to enhance pectin affinity toward other components within food matrices. Fiber content, viscosity, pectin solubility, DM, and monosaccharide composition were determined for both pasteurized, and LTB+pasteurized blueberry purees. The results showed that neither the amount of fiber, nor the viscosity were affected by LTB, indicating that this treatment did not result in any significant pectin depolymerization and degradation. LTB caused a decrease both in pectin DM from 58-67% to 45-47% and in the amount of water-soluble pectin fraction, the latter remaining the major fraction of total pectin at 52% to 57%. A LTB is a simple and mild process to produce blueberry purees with mostly soluble and low-methylated pectin in order to extend functionality and opportunities for interactions with other food ingredients.

농축 블루베리 퓌레 열처리 시 pH 조절제의 품질 저하 억제 효과

농축 블루베리 퓌레 열처리 시 pH 조절제의 품질 저하 억제 효과

Thermal stability of primary and secondary metabolites in highbush blueberry (Vaccinium corymbosum L.) purees

Blueberry fruits are frequently processed to different products, which are subjected to different temperature regimes during their manufacture. Therefore, the aim of this study was to evaluate the impact of different temperatures (4 °C, room temperature, 50 °C, 75 °C and 100 °C) on the stability of soluble solids, pH value, color and primary and secondary metabolites in blueberry purees of three different highbush cultivars ('Bluecrop', 'Jersey' and 'Earliblue'). Soluble solids content increased with heating; conversely, 8–16% lower levels of total sugars and organic acids have been measured in purees subjected to highest temperature regimes. Blueberry purees prepared at higher temperatures were also characterized by a 11–32% decrease in total phenolic content and a lower content of all analyzed phenolic groups. A major, 38–64% decrease in total anthocyanins has been linked to darker color of purees, subjected to higher temperature. The loss of secondary metabolites was cultivar specific and higher temperatures caused a greater decrease on 'Earliblue' and 'Jersey' purees compared to 'Bluecrop' puree.

Effect of fermentation and sterilization on anthocyanins in blueberry.

Blueberry products have various health benefits due to their high content of dietary anthocyanins. The aim of this study was to investigate the impact of fermentation and sterilization on total anthocyanin content, composition and some quality attributes of blueberry puree. The blueberry puree used here was fermented for 40 h at 37 °C by Lactobacillus after sterilization. The method of ultra-performance liquid chromatography-mass spectrometry was optimized for the rapid analysis of anthocyanins. Quality attributes including pH, color, total soluble solids and viscosity were measured. A total of 21 anthocyanins and five anthocyanidins were quantified by ultra-performance liquid chromatography. Fermented blueberry had reduced total anthocyanin content (29%) and levels of individual anthocyanins compared with fresh blueberry. Total anthocyanin content was decreased 46% by sterilization, and different degradation behavior of individual anthocyanin was appeared between fermented and sterilized-fermented blueberry puree. Fermentation and sterilization decreased the total soluble solids and pH and changed color parameters, while minimally influencing viscosity. The loss of total anthocyanin content by fermentation was related to the unstable structure of blueberry anthocyanins. Anthocyanins are sensitive to temperature (>80 °C), and degradation of anthocyanins by sterilization in blueberry should be considered in the fermentation procedure. © 2016 Society of Chemical Industry.

Assessment of the Effects of Ultrasonics and Pulsed Electric Fields on Nutritional and Rheological Properties of Raspberry and Blueberry Purees

The impact of pulsed electric fields (PEF) in continuous, ultrasonication (US), and combined methods was evaluated in red raspberry (Rubus strigosus) and blueberry (Vaccinium corymbosum) purees in order to assess their effects on nutritional quality and rheology. Nonenzymatic browning was inhibited, but only US and combined methods were capable to inactivate polyphenol oxidase (PPO) in a considerable extent (p < 0.01). High recovery of biocompounds was observed, with a significant extraction (p < 0.01) of flavonoids (+20 %) and anthocyanins (+30 %) in raspberry and blueberry purees, respectively. Ascorbic acid was preserved, and the gentle effect of nonthermal technologies in antioxidant capacity was confirmed by DPPH• scavenging value, which significant increased for raspberry (p < 0.01). The rheology of purees was dramatically modified by US, especially in blueberry, showing a progressive shift from non-Newtonian to Newtonian model, accompanied with a reduction in apparent viscosity values. Overall, the enhanced nutritional quality makes both technologies suitable for berry treatment, although changes on rheological properties should be taken into account for process design.

Degradation kinetics of total anthocyanins and formation of polymeric color in blueberry hydrothermodynamic (HTD) processing

Anthocyanin degradation and formation of polymeric color of blueberry puree in novel hydrothermodynamic (HTD) processing was studied. Anthocyanin degradation was non-significant in the range of temperatures from 2.5 to 80 °C, becoming significant above 80 °C (p < 0.05). Analysis of kinetic data indicated a first-order reaction for the degradation of blueberry anthocyanins with energy of activation 66.37 kJ/mol and half-lives (t1/2) of 346.6, 187.3, 123.8, 80.6 and 38.7 min at temperatures of 70, 80, 87.5, 95 and 105 °C respectively. Polymeric color formation followed zero-order kinetics, progressively increasing with temperature. Polyphenol oxidase (PPO) and peroxidase (POD) were completely deactivated at 80 °C, which can be the reason of better shelf-life stability (t1/2 = 533.2 and 216.6 days at 4 and 20 °C, respectively). The beneficial aspect of technology on anthocyanin degradation and storage stability could be attributed to unique combination of temperature-pressure regimes of HTD processing.

Short-term blueberry intake enhances biological antioxidant potential and modulates inflammation markers in overweight and obese children

Oxidative stress and inflammation together play a crucial role in the obesogenic process, and imbalances in reactive oxygen species, free radicals and antioxidants have been reported as being major mechanisms underlying obesity-related co- morbidities. Obesity and oxidative stress may be present even within the first two decades of life, and chronic exposure to systemic inflammation may contribute to the onset and progression of cardiovascular disease and diabetes. Bioactive compounds present in blueberry have been shown to have many positive effects on human health. The present study was carried out in northern Italy on a population of 24 overweight and obese children (8-13 years), divided into three groups: the first consumed fresh blueberries, the second blueberry puree, while a third control group did not consume any blueberries. The children's anthropometric measures were taken and serum markers related to inflammation, CRP, ceruloplasmin, and complements C3 and C4 were measured during the eight weeks they ate either fresh blueberries or blueberry puree. BAP test (Biological Antioxidant Potential) values of the three groups were monitored throughout the entire study and correlated with inflammatory, metabolic and anthropometric markers. The results showed a higher increase in antioxidant levels in the group that ate fresh berries than in the group that ate puree, while the control group's BAP values decreased over the eight weeks of the study. Our results show that increased consumption of blueberries, hence antioxidant intake, may also have a positive effect on markers of inflammation and oxidative stress in overweight and obese patients during childhood.

Rheological behavior of blueberry ( Vaccinium ashei) purees containing xanthan gum and fructose as ingredients

In the present work the influence of temperature, xanthan gum and fructose addition on rheological behavior in steady state of blueberry puree was evaluated. The blueberry pulp was formulated with addition of xanthan gum (1.6, 2.0, 2.5, 3.0 and 3.3%) and fructose (6.6, 10.0, 15.0, 20.0 and 23.4%). Rheological data were obtained by shear rate scan tests in a rotational rheometer, with geometry of concentric cylinders in temperatures of 27, 40, 60, 80 and 93 °C. The thixotropy analysis was made through the calculation of the difference between the areas under up and down cycles’ flow curves. The analysis of the formulation influence on puree viscosity was carried out in two stages: i) selection of an appropriate rheological model for representation of data obtained in experiments and ii) statistical analysis of formulation and temperature influence on rheological parameters of selected model. Three 2-parameter models (Bingham, Ostwald–de Waele and Casson) and three 3-parameter models (Herschel–Bulkley, Mizrahi–Berk and Sisko) were tested. Based on the values of correlation coefficients and variance of the estimated parameters, Casson model was chosen for fitting of experimental data. The content of xanthan gum appears as a determinant variable of the rheological behavior of the puree, both at short and long times. The correlation among the variables studied was represented through statistical models which could be used for the development of formulations with specified viscosity in the range of additive concentrations studied.

Sensory Attributes and Phenolic Content of Precooked Pork Breakfast Sausage with Fruit Purees

ABSTRACT: The aim of this study was to evaluate the phenolic content and sensory attributes of precooked pork breakfast sausage patties enhanced with blueberry puree (BBP) or dried plum puree (DPP). Five treatments at a standardized percent fat were evaluated, which included a control, 5% or 10% BBP, and 5% or 10% DPP. The addition of BBP and DPP at 5% and 10% of the weight increased the total phenolics in the cooked sausage an average of 36%. Comparisons of fruit type, percentage of fruit added, and fruit treatments versus control were all significant (P < 0.05) for tenderness, cohesiveness, and pork sausage flavor, but were not significant for other attributes. Fruit type × fruit amount interaction was significant for sweetness. As fruit amount increased, sweetness scores also increased with the DPP treatments being sweeter than the BBP treatments (P < 0.05). A consumer panel of 10- to 12-y-old children (n= 108) rated 5% BBP and control the highest for overall like compared with other treatments, and scored both BBP treatments equal to the control for taste (P > 0.05). Approximately, 90% of the children said they would like to eat the BBP sausage again while approximately 70% said they would like to eat the DPP sausage again. Results indicate the addition of BBP or DPP to precooked pork breakfast sausage can increase phenolics that may be nutritionally beneficial while also having consumer appeal.