Antioxidant capacities vary substantially among cultivars of rabbiteye blueberry (Vaccinium ashei Reade)

Fruits from forty‐two blueberry cultivars, including thirty‐six rabbiteye (Vaccinium ashei Reade), three V. ashei hybrid derivatives and three northern highbush (V. corymbosum L.) standards, were evaluated for their antioxidant activities against peroxyl free radicals (ROO˙), hydroxyl radicals (OH˙), hydrogen peroxide (H₂O₂), superoxide radicals () and singlet oxygen (¹O₂) radicals. The differences in scavenging capacities for these radicals among forty‐two selected blueberry cultivars were significant. Oxygen radical absorbance capacity values ranged from 33.8 to 118.7 μmol Trolox equivalents (TE) g fresh wt^?1, 196.1 to 518.8 μmol TE g dry wt^?1 and 7.1 to 22.2 μmol cm^?2‐surface area. Extracts from fruit of pure rabbiteye had higher levels of scavenging capacities of oxygen species , ¹O₂ and H₂O₂ compared to V. ashei hybrid derivatives and northern highbush blueberry standards. The rabbiteye cultivars ‘Early May’ and ‘Centurion’ had the highest scavenging capacity for the reactive oxygen species, not only for ROO˙ and ˙OH, but also for , ¹O₂ and a strong oxidant, H₂O_2. In contrast, ‘Pink Lemonade’ (pink‐fruited) had the lowest ability to inhibit free radical activity of ROO˙,˙OH, ¹O_2, and H₂O_2.‘Snowflake’ had the lowest scavenging capacity for . Blueberry cultivars with high antioxidant activity and radical scavenging capacity have potential to improve human health and can possibly be used as parents for future blueberry breeding programs to develop new blueberry cultivars with higher antioxidant activity.     

Effect of Iberian × Duroc genotype on composition and sensory properties of dry‐cured ham

BACKGROUND: Dry‐cured ham quality from three different Iberian × Duroc genotypes was studied: GEN1, Iberian × Duroc1; GEN2, Duroc1 × Iberian; GEN3, Duroc2 × Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The line Duroc1 (DU1) was selected for the manufacture of dry‐cured meat products, whereas the line Duroc2 (DU2) was selected for meat production with low carcass fat. RESULTS: Dry‐cured hams from all genotypes had similar chemical composition. However, intramuscular fat of dry‐cured hams from GEN3 was more unsaturated than that from GEN2, while GEN1 was intermediate. Lipid oxidation, measured as 2‐thiobarbituric acid‐reactive substances (TBARS) and hexanal content, was similar between genotypes. The colour of hams was affected by genotype; hams from GEN2 showed higher lightness (CIE L*), while those from GEN3 had a less intense colour (lower a* and C*). Texture measured instrumentally did not differ between genotypes; however, in the sensory analysis, panellists considered hams from GEN3 more fibrous, while those from GEN2 were considered juicier. Hams from GEN3 were also perceived as saltier and more acid. CONCLUSION: Genotype affected the quality of Iberian hams, with those from GEN3 being of lower quality, and this genotype was considered less suitable for the manufacture of Iberian dry‐cured ham. Copyright © 2007 Society of Chemical Industry     

Glass Transition Study in Model Food Systems Prepared with Mixtures of Fructose,Glucose, and Sucrose

Abstract: The glass transition temperature of model food systems prepared with several glucose/fructose/sucrose mass fractions was studied using differential scanning calorimetry (DSC). A distance‐based experimental design for mixtures of 3 components was used to establish the proportion of sugars of the model systems. Thus, 32 compositions including individual sugars and sugar mixtures, both binary and ternary were prepared and analyzed. Thermograms showing the complete process of heating–cooling–reheating were used to determine the precise glass transition temperature during cooling () or reheating () in amorphous sugars. The Scheffe cubic model was applied to experimental results to determine the influence of sugar composition on the glass transition temperature (P < 0.05). The final model proved to be appropriate (R² > 0.97, CV < 9%, model significance <0.0001) to predict the T_g values of any dry mixture of amorphous fructose, glucose, and sucrose. Practical Application: The experimental values of T_g and the mathematical model proposed in this work may be of great use for making available T_g data that involves the mixture of more than 2 sugars and thus could be used as a tool for predicting the storage stability and quality of dehydrated products such as fruit powders.     

Gamma radiation effect on quality changes in vacuum‐packed squid (Illex argentinus) mantle rings during refrigerated (4–5 °C) storage

The effect of gamma radiation (0, 1.8, 3.3 and 5.8 kGy) on microbiological, chemical and colour characteristics of vacuum‐packed squid (Illex argentinus) mantle rings was studied. Total viable counts; psychrotrophic bacteria counts, Escherichia Coli, Staphylococcus aureus and Clostridium perfringens; total volatile basic nitrogen (TVBN) and colour difference were analysed during 29 days of storage at 4–5 °C. Higher doses of gamma radiation significantly reduced Total Viable, phychrotrophic counts and TVBN production (P < 0.05) in a dose‐dependent way, delaying squid spoilage. Colour difference of non‐irradiated samples with respect to first day significantly increased while it was constant in radiated samples during 22 days (P < 0.05). Independently from the dose, radiation avoided colour changes of squid rings. Gamma irradiation was effective in delaying deterioration reactions, improving microbiological, chemical and colour quality of vacuum‐packed squid rings stored at 4–5 °C.     

Use of thiamine for controlling Alternaria alternata postharvest rot in Asian pear (Pyrus bretschneideri Rehd. cv. Zaosu)

The effects of thiamine (vitamin B₁) against Alternaria rot caused by Alternaria alternata and its possible mechanism in harvested Asian pear fruit were investigated. Thiamine strongly inhibited spore germination and mycelial growth of A. alternata in vitro. Thiamine at a concentration of 100 mm effectively inhibited the development of Alternaria rot, enhanced the activities of defence‐related enzymes, such as phenylalanine ammonia‐lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD), and increased the content of flavonoids, phenolics and lignin. Thiamine also affected reactive oxygen metabolism of the pear fruit by increasing its production and H₂O₂ content, and enhancing the activities of major detoxifying enzymes, such as superoxide dismutase (SOD). These findings suggest that the effects of thiamine on Alternaria rot in pear fruit may be associated with its direct fungitoxic property against the pathogens, and the elicitation of biochemical defence responses in the fruit.     

A Survey of Nitrate and Nitrite Concentrations in Conventional and Organic‐Labeled Raw Vegetables at Retail

A national survey of the nitrate () and nitrite ( ) concentrations in raw and highly consumed vegetables available at retail in the United States was conducted. A total of 194 samples of fresh broccoli, cabbage, celery, lettuce, and spinach categorized as conventional or organic by label were collected from 5 major cities in different geographic regions of the United States and analyzed to determine and concentrations. There were no differences in the mean values of conventional compared with organic vegetables taken from the 5 metropolitan areas. However, significant differences in mean pairwise comparisons between some conventional and organic vegetables for content were observed. The mean concentration of both conventional and organic vegetables ranged between 0.1 and 1.2 mg/kg of fresh weight (FW) with the exception of conventional spinach that contained 8.0 mg/kg FW. Mean contents of conventional broccoli, cabbage, celery, lettuce, and spinach were 394, 418, 1496, 851, and 2797 mg/kg FW, respectively, while their organic‐labeled counterparts averaged 204, 552, 912, 844, and 1318 mg/kg FW. In most cases, organic vegetables were numerically lower in content than their conventional counterparts. Based on survey results, the finding that low levels were observed in some organic vegetables in different cities may warrant further study to determine if true differences exist, due to production practices, seasonal differences, and the magnitudes of those differences. Furthermore, the geographic differences in content of vegetables may flaw estimates of daily and exposure.     

Fracture properties of potato crisps

The Weibull modulus of potato crisps is about 4, comparable with ceramic materials, with a characteristic strength of about 1.5 MPa. This combination of brittleness and weakness gives crispness. The critical stress intensity factor (K_IC) and the energy of fracture (R) are around 0.12 MPa and 45 J m^–2, respectively. There was no significant difference between the material values obtained for the fracture properties of crisps of a range of subjective ‘crispness’ as measured by a trained organoleptic panel. Crispness is ranked by the structural bending strength. Centrally loaded plate tests give qualitative evaluation of crispness. Both these tests could be used in quality control, with advantage over organoleptic tests such as cost, the time required, objectivity, consistency of results, the relation of the measured parameters to standard materials tests and the relatively small amount of material that is needed by comparison.     

Phenolic profile and changes in the antioxidant activity of crabapple (Malus domestica cv Royalty) fruit during maturation on the tree

The fruits of crabapple (Malus domestica cv Royalty) harvested at six times during fruit maturation on the tree (60, 80, 100, 120, 140 and 160 day after full bloom, DAFB) were evaluated for their antioxidant potentials by various assays such as DPPH, ABTS, superoxide anion, hydroxyl radical and ferric reducing power. Total phenolic and flavonoid were analysed and characterised using HPLC‐DAD‐MS/MS. Results showed that the Royalty fruits harvested on 60 DAFB had the strongest scavenging activity against DPPH, ABTS and radicals ( = 0.37 mg mL^?1,  = 0.19 mg mL^?1 and  = 4906.63 U L^?1) and ferric reducing power (FRAP = 2.85 mol Fe²⁺ per kg dw), which highly correlated with its high amount of total phenolics of 130.17 mg gallic acid equivalents (GAE) per gram dry weight and total flavonoid of 866.15 mg rutin equivalents (RE) per gram dry weight. Eight phenolic compounds were identified in the Royalty extract of 60 DAFB as caffeic acid, eriodictyol rhamnoside, phloretin hexoside I, coumaroyl guinic acid, quercetin hexoside, phloretin hexoside II, quercetin pentoside and quercetin rhamnoside. These findings suggest that Royalty could be potentially used as a promising source of natural antioxidants in the development of functional foods.     

Determination of certain quality characteristics,thermal and sensory properties of ice creams produced with dried Besni grape (Vitis vinifera L.)

In this study, the effect of adding dried Besni grape (BG) at different concentrations on the physico‐chemical characteristics, colour values, total phenolic and flavonoid contents, glass transition (), melting (), freezing (T_f) and melting (T_m) point temperatures, and sensory properties of ice creams was investigated. Generally, the addition of BG caused a statistically significant (P < 0.01) increase in total solids, ash, fat, viscosity, first dripping times, complete melting times and a* colour values, while it decreased protein, pH, overrun, L*, b*, , , T_f and T_m values. The colour scores of ice cream samples showed a statistically significant increase (P < 0.05) with the increment of BG concentration, while the effects of BG addition on texture, resistance to melting, flavour, gumming structure and overall acceptability scores were not statistically significant.     

Influence of nutrient solutions in an open‐field soilless system on the quality characteristics and shelf life of fresh‐cut red and green lettuces (Lactuca sativa L.) in different seasons

BACKGROUND: Little information is available about the impact of nutrient solution ion concentration on quality characteristics and shelf life of fresh‐cut lettuce grown in soilless systems in open field. Three lettuce genotypes, lollo rosso and red oak leaf as red‐leafed genotypes and butterhead as green‐leafed genotype, were studied. The influence of three nutrient solutions with low, medium and high ion concentrations, which varied in the macroanion (NO$_{3}^{-}$ ) and macrocations (K⁺, Ca²⁺ and NH$_{4}^{+}$ ), were compared in summer and winter. RESULTS: The nutrient solutions evaluated in this study for the production of lettuce in a soilless system did not strongly influence the quality characteristics of the raw material. When the ion concentration of the nutrient solution was increased, fresh weight decreased, although it depended on the genotype and season. Maturity index and dry matter content varied with the season but independently of the nutrient solution. In summer, maturity index was higher and dry matter lower than in winter. Initial texture and visual quality were not influenced by the nutrient solution. Medium ion concentration provided the highest content of vitamin C and phenolic compounds. Our observations pointed out that the genotype had a strong influence on the shelf life of the fresh‐cut product with minor differences among nutrient solutions. In general, red‐leafed lettuces showed the highest antioxidant content, helping the maintenance of sensory characteristics throughout storage. CONCLUSION: The combination of optimal nutrient solution ion concentration and suitable cultivar is considered essential to ensure lettuce post‐cutting life. Copyright © 2012 Society of Chemical Industry     

Powdered barley sprouts: composition,functionality and polyphenol digestibility

This study was performed to evaluate the phytochemical composition, in vitro antioxidant capacity, antihyperglycaemic and anti‐inflammatory activities, and simulated gastrointestinal digestion of 7‐day‐old freeze‐dried barley sprouts (BS), one hybrid and one nonhybrid variety: ‘NS565’ (BSNS) and ‘Golozrni’ (BSG), respectively. BSNS expressed significantly higher (P ≤ 0.05) content of total phenols, chlorophyll and carotenoids. Phenolic compounds were the most dominant bioactives in both BSNS and BSG (713.25 and 479.02 mg GAE 100 g^?1 DW, respectively). BSNS possessed significantly higher (P ≤ 0.05) antioxidant capacity, evaluated by DPPH and ABTS assays, and reducing power ( = 0.54 mg mL^?1; IC₅₀^ABTS = 0.79 mg mL^?1; RP_0.5 = 9.35 mg mL^?1). Antihyperglycaemic and anti‐inflammatory activities of BSNS ( = 1.43 mg mL^?1;  = 1.86 mg mL^?1) were also significantly higher (P ≤ 0.05) than BSG ( = 1.97 mg mL^?1;  = 4.40 mg mL^?1). In vitro simulation of gastrointestinal digestion showed higher release of phenolic compounds in intestinal fluid than in gastric fluid.     

Modelling growth of Lactobacillus plantarum and shelf life of vacuum‐packaged cooked chopped pork at different temperatures

Lactobacillus plantarum growth in a vacuum‐packaged cooked meat product under different storage temperatures (4, 10 and 16 °C) and the relation between the microorganism growth and sensory quality were investigated. The Gompertz model was fitted to experimental counts of L. plantarum showing a good fitting to growth curves at different temperatures. A root‐square secondary model and linear model were satisfactorily fitted to estimated growth rates () and lag times (), respectively. The sensory attributes (colour, flavour, taste, appearance) were also evaluated due to their importance to the global quality (Q). The sensory deterioration was detected several days after L. plantarum reached the stationary phase, that is, 59, 45 and 25 days for 4, 10 and 16 °C, respectively. According to results, sensory deterioration was related to time when microorganism reached late stationary phase, phenomenon known as ‘delayed change’.     

Effects of state/phase transitions on the quality attributes of mango (Mangifera indica L.) during frozen storage

Effects of different state/phase transitions (temperature fluctuations) on quality attributes of mango cubes during frozen storage were investigated. Temperature of frozen mango was modulated from ?65 °C to different states, namely, rubbery state , partially freeze‐concentrated state () and glassy states ( and ). Results revealed that frozen samples after 4 weeks of storage in a glassy state showed higher quality in hardness, drip loss, colour and ascorbic acid. Quality of mango still continued to change during frozen storage even in the glassy state without temperature fluctuations. Furthermore, there was a significant decrease in quality attributes of frozen mango subjected to temperature fluctuations above and . Current work indicates glassy state storage can improve retention of quality attributes in frozen mango and glassy state without temperature fluctuation was proposed as the most favourable frozen storage condition.     

Challenges in Model Development for Meat Composition Using Multipoint NIR Spectroscopy from At‐Line to In‐Line Monitoring

This study evaluates the efficiency of multipoint near‐infrared spectroscopy (NIRS) to predict the fat and moisture content of minced beef samples both in at‐line and on‐line modes. Additionally, it aims at identifying the obstacles that can be encountered in the path of performing in‐line monitoring. Near‐infrared (NIR) reflectance spectra of minced beef samples were collected using an NIR spectrophotometer, employing a Fabry‐Perot interferometer. Partial least squares regression (PLSR) models based on reference values from proximate analysis yielded calibration coefficients of determination of 0.96 for both fat and moisture. For an independent batch of samples, fat was estimated with a prediction coefficient of determination of 0.87 and 0.82 for the samples in at‐line and on‐line modes, respectively. All the models were found to have good prediction accuracy; however, a higher bias was observed for predictions under on‐line mode. Overall results from this study illustrate that multipoint NIR systems combined with multivariate analysis has potential as a process analytical technology (PAT) tool for monitoring process parameters such as fat and moisture in the meat industry, providing real‐time spectral and spatial information.     

The effect of enzymatic hydrolysis on the biological properties of Oenothera biennis,Borago officinalis and Nigella sativa seedcake by‐products from oil pressing

The biological properties of ethanolic (50%, v/v) extracts from Oenothera biennis, Borago officinalis, Nigella sativa seedcake before and after enzymatic hydrolysis by alpha‐amylase (EC 3.2.1.1) from Aspergillus oryzae, beta‐glucosidase (EC 3.2.1.21) and beta‐glucanase (EC 3.2.1.6) from Aspergillus niger combinations in a ratio of 1:1:1 were investigated. Total phenolic, flavonoid and reducing sugar content for O. biennis extract after enzymatic hydrolysis was, respectively, 0.5, 1.5 and 2 times higher in comparison with nonhydrolysed extract. Iron‐chelating and radical‐scavenging activity of O. biennis seedcake extract after hydrolysis (IC₅₀ = 0.076 mg mL^?1 and IC₅₀ = 0.050 mg mL^?1) was at a similar level as that nonhydrolyeed (IC₅₀ = 0.070 mg mL^?1 and IC₅₀ = 0.065 mg mL^?1). The antioxidant activity was two times higher after hydrolysis than before enzymatic hydrolysis of O. biennis seedcake extract. Also strong elastase inhibition activity has been shown to O. biennis seedcake extract before (IC₅₀ = 0.095 mg mL^?1) and after enzymatic hydrolysis (IC₅₀ = 0.07 mg mL^?1), respectively. Oenothera biennis and B. officinalis seedcake extracts before and after hydrolysis have stronger antibacterial activity against Pseudomonas aeruginosa strain in comparison with N. sativa seedcake.     

Wheat flour dough Alveograph characteristics predicted by Mixolab regression models

BACKGROUND: In Romania, the Alveograph is the most used device to evaluate the rheological properties of wheat flour dough, but lately the Mixolab device has begun to play an important role in the breadmaking industry. These two instruments are based on different principles but there are some correlations that can be found between the parameters determined by the Mixolab and the rheological properties of wheat dough measured with the Alveograph. RESULTS: Statistical analysis on 80 wheat flour samples using the backward stepwise multiple regression method showed that Mixolab values using the ‘Chopin S’ protocol (40 samples) and ‘Chopin + ’ protocol (40 samples) can be used to elaborate predictive models for estimating the value of the rheological properties of wheat dough: baking strength (W), dough tenacity (P) and extensibility (L). The correlation analysis confirmed significant findings (P < 0.05 and P < 0.01) between the parameters of wheat dough studied by the Mixolab and its rheological properties measured with the Alveograph. CONCLUSION: A number of six predictive linear equations were obtained. Linear regression models gave multiple regression coefficients with $R_{\rm {adjusted}}^{2} > 0.70$ for P, $R_{\rm {adjusted}}^{2} > 0.70$ for W and $R_{\rm {adjusted}}^{2} > 0.38$ for L, at a 95% confidence interval. Copyright © 2011 Society of Chemical Industry     

Cover Image,Volume 98, Issue 9

The cover image, by Noorani Barkat et al., is based on the Research Article Effect of harvest time on the levels of phytochemicals, free radical‐scavenging activity, α‐amylase inhibition and bile acid‐binding capacity of spinach (Spinacia oleracea), DOI: 10.1002/jsfa.8862 .

     

Noninvasive sensing of thermal treatments of Japanese seafood products using imaging spectroscopy

The potential of imaging spectroscopy for noncontact sensing of thermal treatments experienced on Japanese kamaboko was investigated. Samples were thermally treated at 100, 120, 140, 160, 180 and 200 °C to core temperatures of 45, 50, 55, 60, 65, 70, 75 and 80 °C and then promptly cooled and imaged in the short‐wave near infrared spectral range of 900–2500 nm. Partial least square (PLS) regression models were developed using the whole spectral range as well as using the most important wavelengths to predict the core temperature (T_C) and thermal history (TH) yielding a reasonable level of accuracy of ( = 0.86 and RMSEP = 3.9 °C) and ( = 0.83 and RMSEP = 0.29 min), respectively. Moreover, a stepwise linear discriminant analysis (LDA) model was developed for identifying samples whose core temperatures reached a threshold of 65 °C. The LDA model yielded overall classification accuracy of 93.75% in both calibration and validation sets. The resulting discrimination function was then applied in a pixel‐wise manner to produce understandable classification maps to exhibit the difference among samples with high accuracy.     

Physical changes and physiological characteristics of red and green peel during nectarine (cv. Hu018) maturation

BACKGROUND: The aim of this study was to determine physical changes in nectarine and distinctive physiological characteristics related to red and green peel under stresses occurring during fruit maturation, information on which is currently not available. RESULTS: Fruit firmness increased from 4 to 6 weeks after blooming (WAB) then decreased from 6 WAB until ripening. Anthocyanins in red and green peel during nectarine maturation were identified by high‐performance liquid chromatography as cyanidin 3‐glucoside together and, at a much lower level, cyanidin 3‐rutinoside. Cyanidins in red and green peel decreased from 4 to 8 WAB then increased from 8 to 12 WAB. Anthocyanin contents were positively correlated with PAL, POD, A*, MDA and O$_{2}^{\bullet-}$ values and inversely correlated with L* and B* values. Red and green peel during maturation could be separated by hierarchical cluster analysis of the tested data. CONCLUSION: This study has provided an overview of red and green peel characteristics during nectarine (cv. Hu018) maturation. Values of A*, anthocyanins, O$_{2}^{\bullet-}$ , MDA, PAL, PPO and POD in red peel were higher than those in green peel, while values of L*, B* and chroma in red peel were lower than those in green peel throughout fruit maturation. Copyright © 2011 Society of Chemical Industry     

Cover Image,Volume 97, Issue 15

The cover image, by Rosa Isela Ventura‐Aguilar et al., is based on the Review Cactus stem (Opuntia ficus‐indica Mill): anatomy, physiology and chemical composition with emphasis on its biofunctional properties, DOI: 10.1002/jsfa.8493 .