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The studies expounding on the effects of storage conditions on texture changes are limited. The researchers have been proposing methods to measure pecan texture instrumentally. But current protocols and/or attributes fail to address huge variability during experimentation. Additionally, there are no predictive models to estimate changes in pecan texture during storage. This study addresses all the above concerns and investigates the effects of different relative humidity (RH, 30–90%) and packaging material (Polyethylene‐Nylon [PEN], polypropylene [PP], low density polyethylene [LDPE], and metallic laminates [ML]) on pecan texture, introducing a rift ratio (F/H or fracturability to hardness ratio) to address variability in the data and predictive model to estimate changes in the textural attribute of pecans during storage. The textural analysis was conducted on pecan cores and intact pecans to measure the area under curve, fracturability, hardness, cohesiveness, chewiness, springiness, and rift ratio. It was observed that values for the rift ratio obtained using the intact pecan method had high R2 (0.72) as compared to the rest of the textural attributes. A three‐parameter logistic model was employed to predict pecan texture during storage. The pecans stored at 75, 80, and 90% reached the rift ratio (F/H) of 0.5 at approx. 115, 3, and 0.15 days (~ 4 hr), respectively. Similarly, pecans stored in LDPE, PP, and PEN packs at 80% reached rift ratio (F/H) of 0.5 at approx. 26, 57, and 78 days, respectively. The presence of any kind of package delayed fracturability loss by at least eight folds at 80% RH. The pecans stored in ML did not experience a significant change in textural attributes [ABSTRACT FROM AUTHOR]

Summary: Water blanching is widely used in food industry, but imprudent process causes considerable quality deterioration. To determine optimum condition, the effect of water blanching at different temperature (80, 90 and 98 °C) and time (0–10 min) on the characteristics of samnamul was investigated. Total phenolic and flavonoid content and antioxidant activities showed dramatic increase up to maximum and decreased rapidly as further blanching prolonged at all temperatures. The blanching at 98 °C for 30 s showed the highest values of them. Phenolic compounds such as shanzhiside methyl ester, isoquercetin, quercetin 3‐O‐rhamnoside, kaempferol 3‐O‐glucoside and sergeolide showed different temperature dependence. At 30 s, quercetin derivatives levels increased with increasing temperature and showed highest heat‐stability. Based on our study, the blanching at high temperature of 98 °C for a short time of 30 s may be important to increase or maintain nutritional quality, while oxidative enzyme activities and the microorganism numbers decreased. [ABSTRACT FROM AUTHOR]

There has been increasing concern over the potential carcinogenic problem of the synthetic antioxidants in oil industries. Tomato extract was prepared by supercritical‐CO2, which may be a natural antioxidant. The supercritical fluid tomato extract (SFTE) was added in perilla oil (PO) and investigated the oxidative stability of PO and compared with control and those of the PO containing α‐tocopherol as a positive control. SFTE had a high content of lycopene (64.91%) and β‐carotene (34.93%), which led to significantly higher antioxidant capacity than that of the α‐tocopherol. During the thermal treatment at 65°C for 24 hr, the PO containing SFTE at various concentrations (100, 300, 500, and 1,000 µg/ml) showed significantly lower acid value and peroxide value, and at least 1.5 times higher induction period than those of the control and α‐tocopherol‐added PO at the same concentrations. The results suggest that SFTE may be an attractive natural antioxidant in oil industries. Practical Applications: Oxidation is a major problem causing the quality deterioration of edible oils which are rich in unsaturated fatty acids. Generally, chemically synthesized antioxidants are widely added to vegetable oils for retarding oxidative deterioration. But, these antioxidants are potentially carcinogenic to human health. SFTE produced in this study can be attractive alternative natural antioxidant over widely used α‐tocopherol and chemically synthesized antioxidants for preventing the lipid oxidation in food industries. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to determine the efficacy of supercritical carbon dioxide turmeric extract (STE) on the oxidative stability of perilla oil (PO), as measured by acid value (AV), peroxide value (PV) and oxidation induction time and compared to control and α‐tocopherol containing PO as a positive control. The antioxidant activity was determined by DPPH, ABTS and FRAPS assays and individual bioactive compounds identified by chromatography. STE demonstrated significantly higher antioxidant activity than the α‐tocopherol. The major components of the STE were identified as ar‐turmerone, turmerone, curlone and bisabolene by GC‐MS and curcumin and demethoxycurcumin by UPLC‐Q‐TOF MS. During thermal treatment at 65 °C for 24 h, the PO containing STE at different concentrations (100, 300, 500 and 1000 μg mL−1) had significantly lower AV and PV, and at least 1.5 times higher induction period than those of the control and α‐tocopherol‐incorporated PO. [ABSTRACT FROM AUTHOR]

Summary: Further investigations of almond degradation under typical industrial storage conditions from a quantitative perspective are warranted. This study modeled effects of packaging, temperature (TEMP), relative humidity (RH) and roasting on chemical attributes of almonds stored according to common industry practices throughout 16 months. Roasted samples were stored in high‐barrier bags (HBB) or polypropylene bags (PPB) at multiple combinations of TEMP and RH. Raw samples were held in unlined cardboard cartons (UC) or PPB under the same conditions. Almonds were assessed bimonthly for oxidation products, free fatty acids, moisture content and water activity. Results indicated roasting almonds improved quality preservation. Models showed HBB (rather than PPB) to provide benefits to stability comparable to reductions in storage TEMP of ~15 to 30 °C. PPB (rather than UC) showed benefits to peroxide formation of similar magnitude. Our data shows HBB to be a superior packaging choice, and UC to associate with the greatest rates of degradation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Consumer demand for low‐fat foods has been increasing as a result of attempts to reduce obesity and chronic diseases. Bovine heart was defatted using supercritical CO2 (SC‐CO2) at different pressures together with solvent extraction to produce a protein‐based functional ingredient for low‐fat food products. Thermal and functional characteristics of control and defatted samples were compared. RESULTS: Supercritical CO2 treatment at high pressure results in more removal of fat, producing a protein‐rich defatted bovine heart (DBH). The differential scanning calorimeter (DSC) thermograms and SDS‐PAGE bands for SC‐CO2‐treated DBHs were similar to those of the control sample, indicating high protein stability and better functionality. Hexane‐treated DBH showed no major thermal peaks and very diffuse bands in SDS‐PAGE, indicating denaturation of proteins during solvent extraction. No denaturation of proteins in SC‐CO2‐treated DBHs resulted in significantly higher water/oil absorption capacities (3320.00 and 2630.00 g kg−1, respectively), total soluble solids (822.20 and 208.71 g kg−1 at pH 3.5 and 6.5, respectively), foaming capacities (149.37%), and emulsion activity (66.89%) than the hexane‐treated DBH. CONCLUSION: Supercritical CO2 treatment of DBH led to higher thermal stability and functional properties than the control and hexane‐treated DBH. Defatted bovine heart using SC‐CO2 can be a functional ingredient for various low‐fat and high‐protein food products for health‐conscious consumers. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Roasting is a critical step in chocolate processing, where moisture content is decreased and unique flavors and texture are developed. The determination of the degree of roasting in cocoa beans is important to ensure the quality of chocolate. Determining the degree of roasting relies on human specialists or sophisticated chemical analyses that are inaccessible to small manufacturers and farmers. In this study, an electronic nose system was constructed consisting of an array of gas sensors and used to detect volatiles emanating from cocoa beans roasted for 0, 20, 30 and 40 min. The several signals were used to train a three‐layer artificial neural network (ANN). Headspace samples were also analyzed by gas chromatography/mass spectrometry (GC/MS), with 23 select volatiles used to train a separate ANN. RESULTS: Both ANNs were used to predict the degree of roasting of cocoa beans. The electronic nose had a prediction accuracy of 94.4% using signals from sensors TGS 813, 826, 822, 830, 830, 2620, 2602 and 2610. In comparison, the GC/MS predicted the degree of roasting with an accuracy of 95.8%. CONCLUSION: The electronic nose system is able to predict the extent of roasting, as well as a more sophisticated approach using GC/MS. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: It has been difficult to produce acceptable pecan butters as the high oil content results in a product that flows and separates too easily. The objective of this work was to create pecan butters with varying oil levels (50–70%) and determine which would give the most acceptable product. Consumers rated pecan butters with 55–60% oil the most acceptable, whether roasted or not. Acceptability varied most in terms of texture and spreadability, but not flavor. Under large deformation firmness varied from 51.8 g (70% oil) to 4,880 g (50%) oil, while “spreadability” ranged from 19.2 to 7748 (g/s). Samples with 70% oil had the lowest viscosity and were Newtonian. Pecan butters with 50–55% oil had high viscosity and were shear thinning. Yield stress decreased with oil content, ranging from 0.014 to 500 Pa. The storage modulus (G′) increased from ∼7 Pa for samples with 70% oil up to 260,000 Pa for those with 50% oil. In conjunction, tan δ decreased from 1 to 0.07, showing the products take on much more solid‐like behavior as oil is removed. In conclusion, the rheological properties of pecan butter were quite sensitive to the amount of oil in the product. Differences in acceptability were primarily due to “texture” and “spreadability,” suggesting there is a limited range of firmness and spreadability that consumers will deem acceptable. Practical applications: There has been considerable demand for butters and spreads made from a variety of culinary nuts. Pecans generally have too much oil (∼70%) to make a product with proper consistency and stability. In this study, some of the oil was removed to overcome this problem. It was found that pecan butter with 55–60% oil was most acceptable to consumers and with the level of firmness, yield stress, and spreadability most similar to commercial nut butters. The oil was relatively simple to remove from unroasted nuts, thus manufacturers could easily produce more acceptable pecan butter for the market. [ABSTRACT FROM AUTHOR]

BACKGROUND Dried Thunbergia laurifolia leaves are usually prepared using tray drying, resulting in products that have lost substantial amounts of bioactive compounds and antioxidant activity. The maturity of the raw material, blanching techniques and drying methods were investigated in order to select the best condition to produce high qualities of dried T. laurifolia leaves. RESULTS The 1st stage of maturity was selected and steam-microwave blanching ( SMB) for 4 min was adequate for blanching leading to the maximum recovery of bioactive compounds. The modified Halsey model was the best desorption isotherm model. A new drying model proposed in this study was the best to fit the drying curves as compared to five common drying models. Moisture diffusivities were increased with the increase of drying temperature when combining SMB and heat pump-dehumidified drying. Microwave heat pump-dehumidified drying ( MHPD) provided the shortest drying time, high specific moisture extraction rate ( SMER) and could reduce drying time by 67.5% and increase caffeic acid and quercetin by 51.24% and 60.89%, respectively. CONCLUSION MHPD was found to be the best drying method and provided the highest antioxidant activity and bioactive compounds content, high SMER and short drying time. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Electrostatic spraying (ES) was tested as a means of improving shelf life of cupcakes. A 5% potassium sorbate solution was sprayed, with and without electrostatic charging, onto yellow cupcakes for 1-3 s. Image analyses showed that electrostatic charging increased the uniformity of coverage, with 62-78% area coverage with charging and 36-41% without. Samples were also held at 25C and either 75 or 85% relative humidity (RH). At 75% RH, visible mold appeared after 10 days for control and after 11 days for cakes sprayed with sorbate. At 85% RH, fungal growth appeared after 3 days for control, 4 days for cakes with sorbate spray and 5 days for those with ES sorbate. In all cases, ES delayed the onset of mold and subsequent growth as compared with uncharged sprays. ES also provided a small decrease in the rate of firmness development during storage. [ABSTRACT FROM AUTHOR]

Moringa oleifera leaves contain phytochemicals that are retained during heat pump-assisted dehumidified air drying. Changes in phytochemicals, antioxidant capacity and colour were evaluated at 15-35 °C, during storage of dried leaves in polypropylene ( PP) or high barrier ( PET/Al/ PE) packaging for up to 6 months. The aw of samples in PP increased from 0.373 to 0.669. Decreases in total phenolics were greatest at 35 °C in PP (48%) and least at 15 °C in PET/Al/ PE (19%). There were few significant changes in DPPH inhibition after 2 months storage. There was little change in kaempferol and some increase in quercetin. During storage, samples became less green, suggesting breakdown in chlorophyll had occurred. The degradation of flavonoids followed first-order kinetics. The half-life for total flavonoids ranged from 2.13 to 1.47 months for samples stored in PP and from 2.59 to 1.83 months for samples stored in PET/Al/ PE. [ABSTRACT FROM AUTHOR]

BACKGROUND Different ratios of combined sweeteners were modified to produce an acceptable reduced-calorie carrot juice. Various hydrocolloids were investigated to improve juice cloud stability. Changes in juice quality attributes were analysed. RESULTS A combination of the sweeteners aspartame ( ASP), acesulfame potassium ( ACE) and sucralose ( SUC) was partially used to replace the sugar in carrot juice. Sensory studies indicated that juice containing 50 g kg−1 sucrose and 160 mg kg−1 ASP/ ACE/ SUC (6:1.5:1) had the highest acceptability. Thermal processing at 80 °C for 1 min retained acceptable β-carotene (4300 µg kg−1) and did not result in the cooked flavour noted at 65 °C/30 min. Pectin ( PE), carboxymethyl cellulose ( CMC), guar gum ( GU) and gellan gum ( GE) were used to stabilise the juice cloud during storage. The addition of 0.1-0.3 g kg−1 GE or 2.0 g kg−1 GU to reduced-calorie carrot juice greatly improved cloud stability after storage at 4 °C for 30 days. CONCLUSION The formulation of reduced-calorie carrot juice with ASP/ ACE/ SUC (6:1.5:1) provided synergistic sweetness and highly acceptable sensory properties. The addition of 0.3 g kg−1 GE greatly enhanced juice cloud stability during storage. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Rabbiteye blueberries are an excellent source of nutrients and phytochemicals. They are often dried, which can degrade health-promoting compounds. Means of shortening exposure to high-temperature drying air are desirable. Five cultivars of rabbiteye blueberries ('Premier', 'Tifblue', 'Brightwell', 'Alapaha', and 'Powderblue') were dried in a jet-tube fluidized bed air dryer with varying pretreatments including mechanical abrasion and osmotic dehydration. RESULTS Drying time ranged from 66 to 95 min at 107 °C, achieving a final water activity of 0.347-0.605. Prior osmotic dehydration significantly reduced the drying time. Vacuum osmotic dehydration for 70 min achieved similar moisture contents to soaking blueberries for 24 h. Jet-tube dried blueberries exhibited greater color saturation than commercially available blueberries. While drying reduced the total monomeric anthocyanin ( TMA) content, this occurred to a lesser extent than by other processing methods. The total phenolics content ( TPC) and antioxidant capacity (H- ORACFL values) increased after drying. 'Premier' was the most preferred vacuum-infused dried blueberry, with a water activity ( aw) of 0.53 and 157 g H2O kg−1. 'Tifblue' was most preferred amongst the overnight-infused and also unsweetened dried blueberries. CONCLUSION Jet-tube drying can substantially reduce drying times while yielding blueberries with good color, sensory properties, TMA, TPC, and H- ORACFL values. Furthermore, some cultivars produce better-quality dried blueberries than others.© 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Sweet potato chips were produced by vacuum-belt drying and compared to deep-fat fried ( DFF) chips. Two thicknesses (0.8 and 1.5 mm) and four drying temperatures (100, 120, 140 C and mixed temperature [ T-mix] = 100/120/140 C) were investigated. Vacuum-belt dried ( VBD) chips exhibited a similar texture to those DFF while maintaining their natural color and β-carotene content. T-mix chips were found to have the greatest likability. VBD products prepared at the lower temperatures maintained L* C* h values closest to unprocessed sweet potatoes. Environmental scanning electron microscopy micrographs demonstrated that T-mix chips possessed the most uniform cell structure. VBD chips prepared at the T-mix conditions, along with DFF chips, had the lowest degree of hardness but exhibited high fracturability. The former gave a hardness of 504.7 g force with 7.75 fracture peaks, while the latter had a hardness of 500.6 g force and 9.25 fracture peaks. VBD chips manufactured at the lower temperatures retained 55.5 to 65.9% of the sweet potato's β-carotene content, while those prepared at 140 C or by frying retained only 33.1 to 34.2%. Practical Applications Sweet potatoes are a major world food crop, and a valuable source of carotenoids, vitamin C and dietary fiber. Drying and other thermal processes have been employed to preserve sweet potatoes and to convert them into an ingredient form that is convenient for use in food products. Furthermore, there has been a rising demand for low-fat, healthy fruit- and vegetable-based snack items. This study examines the applicability of relatively low-temperature vacuum drying as a process to remove water without substantially altering the vegetable's phytonutrients, yet, can create a structure that produces crispness. Vacuum-belt drying at 100-120 C, or at a specific temperature combination, can yield sweet potato chips that are crisp, have good color, retain a marked quantity of β-carotene and are well-liked by consumers. [ABSTRACT FROM AUTHOR]

The impact of incorporating ground dry-blanched or roasted peanut skins ( PS, three types: light-, medium- and dark-roasted) into peanut butter as a functional food ingredient was examined. A desirable grind size for the PS of less than 300 μm was achieved in most cases by milling the skins with the sugar. Adding ground PS to peanut butter at 1.25, 2.5, 3.75 and 5.0% (w/w) resulted in a concentration-dependent change in the Commission Internationale de l' Éclairage L* C* h values. Peanut butters formulated with medium- and dark-roasted PS showed an increase in hardness, and were generally more adhesive than those without PS or with dry-blanched PS. A marked change in spreadability was found with greater than 2.5% added PS. Incorporation of dry-blanched PS, especially at levels below 3.75%, produced the fewest alterations in physical properties of the peanut butters compared with the control. Importantly, a concentration-dependent increase in the total phenolics content ( TPC) was evident with PS fortification. Dry-blanched PS had a TPC of ∼166 mg (+)-catechin equivalents/g extract and yielded peanut butters with a 32, 33 and 38% higher TPC than found with light-, medium- and dark-roasted skin incorporation, respectively. Correspondingly, dry-blanched PS addition at 1.25, 2.5, 3.75 and 5.0% (w/w) resulted in an increase in the TPC by 86, 357, 533 and 714%, respectively, compared with peanut butters without PS fortification. Practical Applications Peanut skins ( PS) are a rich, inexpensive source of potentially health-promoting compounds, notably proanthocyanidins. However, PS are not often utilized as a functional food ingredient in value-added products. As the primary by-product of the peanut industry, PS are usually discarded as waste with only a small amount used as animal feed. According to our study, ground PS incorporation into peanut butters effectively enhances the total phenolics content of the product and offers product line diversification while still retaining the product's standard of identity. Summarily, our research will aid the peanut industry via (1) by-product/waste stream utilization; and (2) diversification of product lines by creating a value-added peanut product with potential beneficial health properties. [ABSTRACT FROM AUTHOR]

Background Apple pomace is a waste material from apple juice processing, and contains significant amounts of dietary fiber and phytochemicals. Many of these compounds may be degraded post-pressing and during drying operations. Continuous vacuum-belt drying ( VBD) was studied as a means of drying and maintaining quality of apple pomace. The color and chemical properties of samples dried by vacuum-belt drying at different temperatures were evaluated including total phenolics content ( TPC), monomeric anthocyanins ( TMA) and dietary fiber content ( TDF). Results VBD powders were pale golden yellow, and those dried at 80°C did not differ in L*, a* and b* values from freeze-dried powders. VBD pomace had 44.9 to 51.9 g gallic acid equivalents kg−1 TPC, with greatest retention for pomace dried at 80 and 95°C. TPC for pomace dried at 80 or 95°C was not significantly different from that for freeze-dried pomace. TMA levels (74.0 mg C3G kg−1, where C3G is cyanidine 3- O-glucoside equivalents) were highest in pomace vacuum dried at 80°C. TDF ranged from 442 to 495 g kg−1 in vacuum-dried pomace and was not significantly different from TDF of freeze-dried poamce (480 g kg−1). Conclusion In all cases, TPC, TMA and TDF were higher in VBD pomace than in freeze-dried whole apple, while VBD pomace prepared at 80 or 95°C had fiber and phytochemical levels similar to freeze-dried powders. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we examined the changes in ice cream induced by microfluidization at 220-250 MPa of their respective mixes. Two full-fat ice cream mixes were formulated with either xanthan or locust bean gum (LBG) and either frozen into ice cream using a batch freezer or microfluidized and then frozen. The resultant products were subjected to modified texture profile analysis, meltdown testing, and sensory testing for difference and preference. Increases in hardness and adhesiveness were observed between treatment groups in both formulations, as well as an increase in gumminess in the LBG formulation. No difference was observed in meltdown rate between any of the treatment/formulation combinations. Sensory difference tests showed that panelists could distinguish differences between ice creams prepared from low- or high-pressure treated mix. Acceptability tests indicated that consumers preferred the firmness and creaminess of ice cream made from microfluidized mixes with LBG. PRACTICAL APPLICATIONS Dynamic high-pressure processing technologies like microfluidization, can effect marked changes in the quality characteristics of liquid foods, but limited work has been done to fully understand its effects in complex systems. This study shows that ice cream made from microfluidized mixes also expresses changes, that the formulation of the ice cream affects the degree and type of those changes and that in certain cases, the changes effected are desirable to the consumer. This knowledge contributes to a better understanding of the technology, how it interacts differently with different ingredients and provides an insight into potential commercial uses. [ABSTRACT FROM AUTHOR]

ABSTRACT The quality of muffins made with different amounts (0, 15, 30, 45 and 60%) of waxy whole wheat flour (WWWF) blended with conventional whole wheat flour were characterized. High amounts of WWWF blends produced darker but acceptable crust color. WWWF formulations had a softer crumb on day 0 and day 4, but greater firmness after 16 days storage. Samples did not differ in springiness on day 0, but a slight decrease occurred in all samples, and WWWF samples were slightly less springy after 16 days. Proton (1H) NMR showed two distinct relaxation times, indicative of water migration from the crumb of the muffin to the crust. Sensory evaluation showed high overall likability, except for muffins made with 60% WWWF. The 60% muffins had lower volume than all other formulations. Results show that 15-30% WWWF produces a softer, moister muffin, but this advantage is lost after 8-16 days storage. PRACTICAL APPLICATIONS This study shows that 15-30% waxy whole wheat flour blended with conventional whole wheat flour produces softer and moisture whole wheat muffins, with good consumer acceptability. Muffins with WWWF remained softer for 4-8 days, but were firmer than control after 16 days storage. Waxy whole wheat flour also adds additional fiber, so its inclusion in blends with conventional whole wheat may help in the development of higher fiber products with a softer and moister crumb. [ABSTRACT FROM AUTHOR]

The effect of osmotic drying on mango slices of different ripeness, subsequently frozen and stored at− 18C during 20 weeks was evaluated. Osmotic treatments decreased moisture content, titratable acidity, vitamin C levels, lightness (L* ) and firmness, while increasing total soluble solids. Subsequent freezing resulted in further decreases in acidity, vitamin C and firmness. However, samples treated with higher concentrations of sucrose showed less change in properties during frozen storage. Initially less ripe fruit could be softened somewhat by osmotic treatment, with firmness and cohesiveness maintained through frozen storage. Treated less ripe fruit also had lower acid while picking up sugar and had higher vitamin C levels than more mature fruit. PRACTICAL APPLICATIONS The quality of delicate fruits such as mangoes may be compromised by freezing and frozen storage. Tissue damage occurs as ice accrues and concentrates soluble solids. Pretreatment by osmotic drying can remove some of the available water, leaving less available to form ice during freezing. This research investigates combining osmotic dehydration and freezing to promote the quality of mango slices. It also addresses the possibility of using less than ripe, or overripe, fruit to make high quality frozen mango pieces. [ABSTRACT FROM AUTHOR]

The effect of antioxidant, sugar, moisture and storage time on color, texture and microstructure of peanut paste were determined. The addition of 2 or 5% water resulted in decreased lightness (L* ), hue angle (h° ) and chroma (C) values, while tertiary butylhydroquinone (TBHQ) and sugar levels had no effect on color. Peanut pastes with added moisture had increased hardness, adhesiveness and chewiness, and lower cohesiveness and springiness compared with treatments with no added moisture. TBHQ was not a significant factor for texture, but hardness increased with the level of added sugar. Scanning electron micrographs and image analysis of light micrographs confirmed the presence of aggregation of protein bodies in 2 and 5% moisture treatments. The addition of sugar or TBHQ produced no measurable changes in microstructural features. [ABSTRACT FROM AUTHOR]

Determines enthalpy of frozen foods using differential compensated calorimetry. Enthalpy measurements; Control and calibration experiments; Steady state measurements; Enthalpy changes during freezing.

Full‐fat ice cream mixes with xanthan or locust bean gum (LBG) were subject to microfluidization at 220–250 MPa, then formed into ice cream. Particle size increased with average values increasing from 2.64 to 3.93 μm for xanthan mixes, and 2.51 to 4.72 μm for LBG mixes, suggesting interaction between polysaccharide and protein components that then aggregate at the lipid interface. Microfluidization marginally increased the shear‐thinning behavior of mixes while dramatically increasing consistency, with xanthan mixes increasing from K = 1.34 to 13.21 Pa sn, and LBG mixes from 0.127 to 10.64 Pa sn. Oscillatory tests showed the ice cream from microfluidized mixes were softer, with G′ decreasing four‐fold for microfluidized xanthan‐based ice cream. All samples showed G′ and G″ increased with frequency for samples at −10°C, with G″ generally greater than G′, and suggesting a transition‐to‐flow region over the frequency range of 0.1–100 Hz. Transmission electron microscopy showed that hair‐like structures present on casein were lost after microfludization, potentially enhancing aggregation of protein. Scanning electron microscopy also showed distinct differences between ice cream made from control and microfluidized mixes. Overall, the changes observed were more pronounced in the LBG formulation, which we believe is due to the differences in structure between the two gums. Practical Applications: Hydrocolloid stabilizers are a common ingredient of ice cream. This work shows that high‐pressure homogenization can be used to alter the nature of protein–polysaccharide interactions in ice cream mix, ultimately increasing mix viscosity and component interactions. Previous work has shown this can improve ice cream creaminess and sensory properties. Alternately, this work suggests that desirable ice cream properties could be attained with lower levels of stabilizers by using microfluidization. [ABSTRACT FROM AUTHOR]

The quality of bread made from frozen dough is diminished by changes that occur during freezing. New cultivars of waxy wheat flour (WWF), containing less than 2% amylose, offer unique properties for the production of baked products. In this study, dough properties and bread quality were investigated at various levels of WWF (0% to 45% flour weight) and water (55% to 65%). Dough stickiness increased with higher levels of WWF and water. During frozen storage, dough with greater WWF and lower water had less change in stickiness. Maximum resistance to extension (MRE) decreased with higher WWF and water. Dough with greater WWF and less water had less change in extensibility after frozen storage. Dough with greater WWF and water was more extensible. Nuclear magnetic resonance (NMR) studies showed that frozen dough with higher WWF content had lower transverse relaxation ( T2) time of 9 to 11ms. After frozen storage, dough with higher WWF still showed lower T2. Dough with 15% WWF had higher yeast activity. Bread made from 15% and 30% WWF had higher volume in bread made from unfrozen and frozen dough. Bread firmness decreased with higher amounts of WWF and water. This research demonstrated that specific combinations of WWF and water produced a better quality of frozen dough and bread. [ABSTRACT FROM AUTHOR]