Quality of fresh‐cut purple‐fleshed sweet potatoes after X‐ray irradiation treatment and refrigerated storage

The effect of X‐ray irradiation on the quality of fresh‐cut, refrigerated purple‐fleshed sweet potato (PFSP) cubes was investigated. Packaged sweet potato cubes were treated with 0, 250, 500, 750 or 1000 Gy X‐ray irradiation and stored at 4 ± 1 °C for 14 days. After 14 days, total aerobic bacteria counts were 4.1 and 3.2 log₁₀ CFU g^?1, and mould–yeast counts were 3.3 and 3.0 log₁₀ CFU g^?1 in 750 and 1000 Gy treated samples, respectively. Doses up to 1000 Gy did not affect the firmness, moisture content and anthocyanin content of PFSP cubes throughout storage. PFSP cubes' flesh colour did not change during the first week of storage, but lightness (L*) increased after 14 days. Also, irradiation doses at 750 and 1000 Gy decreased saturation (C*) significantly, producing duller flesh colour than controls. Results indicate that X‐ray irradiation treatment at doses up to 1000 Gy can reduce microbial populations while maintaining the physical quality and anthocyanin content of PFSP cubes up to 14 days of storage.     

Proteolysis and textural properties of low‐fat ultrafiltered Feta cheese as influenced by maltodextrin

Maltodextrin was used as a fat replacer in low‐fat ultrafiltered cheese. Fat was replaced with 25% maltodextrin milk solution (w/w) in cheese at 15 and 50% (w/w). The chemical, rheological and sensory properties as well as the microstructure of the cheese samples were evaluated after storage for 2 months at 8 °C. Maltodextrin affected the chemical (pH, dry matter, fat, water‐soluble nitrogen to total nitrogen, nonprotein nitrogen to total nitrogen, total free amino acid) and rheological (mean relaxation time) properties, as well as the microstructure. In general, based on textural properties, sensory evaluation and economic aspects, the 50%‐fat‐reduced sample was selected as the best treatment.     

Application of common wheat bran for the industrial production of high‐fibre pasta

The study was conducted on the effect of the addition of common wheat bran on the chemical composition, physical properties, cooking quality and sensory traits of durum wheat pasta. The pasta was produced on an industrial scale, applying an addition of common wheat bran at doses ranging from 20 to 40%. The products obtained were compared to the pasta from whole‐grain durum wheat flour, produced under identical conditions and with commercially available whole‐grain durum wheat pasta. The increase in the content of wheat bran in the pasta caused a significant increase (Duncan test, P ≤ 0.05) of the content of protein, lipids, ash and total dietary fibre (TDF). The application of 25–30% addition of common wheat bran allowed obtaining the products which are as rich in dietary fibre as the pasta prepared at the same technological parameters from whole‐grain durum flour. The pasta containing up to 30% of bran was characterised with lower losses of dry mass and higher resistance to overcooking, in comparison with the pasta made of whole‐grain durum. Simultaneously, the products had very good sensory quality.     

Improved Extraction and Quality Characterization of Water‐Soluble Polysaccharide from Gamma‐Irradiated Lentinus edodes

Gamma irradiation was applied to the improved extraction of water‐soluble polysaccharides (WSPs) from dried Lentinus edodes. Irradiation provided a dose‐dependent increase in extraction yield (0 kGy, 2.01%; 7.5 kGy, 4.03%; 15 kGy, 7.17%) and purity (0 kGy, 78.8%; 7.5 kGy, 83.1%; 15 kGy, 85.6%) of the WSPs from hot‐water extraction. The effect of irradiation was evident in the degraded microstructures and reduced molecular weights of the WSPs. However, nuclear magnetic resonance, Fourier‐transform infrared, and X‐ray diffraction spectroscopic analyses provided comparable structures of WSPs from nonirradiated and irradiated samples. UV–visible spectra showed a dose‐dependent decline in intensity, but an improvement in thermal properties of the WSPs from the irradiated mushroom samples was observed.     

Prebiotic fibre‐incorporated whey protein crisps processed by supercritical fluid extrusion

Prebiotic soluble fibre (fructooligosaccharides)‐incorporated whey protein crisps were produced by low‐shear supercritical fluid extrusion (SCFX), which utilises supercritical CO₂ as an expansion agent instead of steam. Protein crisps with desirable qualities were obtained with a formulation containing 8% prebiotic fibre and 60% whey protein concentrate (WPC‐80), which gave the final product with a protein content of 49.6% (w/w). A maximum of 70% WPC‐80 and 8% prebiotic fibre could be incorporated to produce expanded protein crisps; however, increasing WPC‐80 from 50% to 70% decreased the end‐product expansion ratio from 3.1 to 1.2 and increased the product hardness and piece density from 1.3 to 2.8 kN and 0.63 to 0.75 g mL^?1, respectively. Addition of 8% prebiotic fibre did not affect the textural qualities of final products. The process produced an expanded protein matrix with unique internal microstructure of uniformly distributed closed cells. Amino acid analysis indicated that 90% of the total lysine and 92% of the total essential amino acids were retained after SCFX processing and oven‐drying, indicating the preservation of protein nutritional quality during the process.     

Production of reduced‐fat Labneh cheese with inulin and β‐glucan fibre‐based fat replacer

The beneficial role of dietary fibre in human nutrition and effects of properties on fermented dairy products have led to a growing demand for the incorporation of novel fibre‐based fat replacers. The aim of the present work was to investigate the possibility of using inulin and oat‐based β‐glucan in Labneh cheese and to analyse the physico‐chemical, textural and sensory properties of the resulting product. The results showed that the textural and sensory properties of the cheese with addition of inulin increased at a 12% fat ratio. Overall, full‐fat and reduced‐fat Labneh cheeses were firmer and had better flavour than all the low‐fat cheeses. However, inulin and oat β‐glucan, as fermentable fibres, were also degraded as fermentable fibres to produce organic acids and had the potential for use as fat replacers in low‐fat dairy systems.     

Modification of poovan banana (Musa AAB) starch by γ‐irradiation: effect on in vitro digestibility,molecular structure and physico‐chemical properties

This study focussed at evaluating the effect of gamma irradiation on the in vitro digestibility, molecular structure and physico‐chemical properties of poovan banana (Musa AAB) starch using γ‐rays from a ⁶⁰Co source at different doses with a dose rate of 2 kGy h^?1. Physico‐chemical properties varied significantly and exhibited strong dose‐dependent relationship. Escalating irradiation leads to decrease in amylose content, pH, swelling power of the starch granules and syneresis of the gelatinised starch, while the same led to an increase in carboxyl content, in vitro digestibility, solubility and water absorption capacity of the starch granules. The results revealed that peak, hold, final and setback viscosities were significantly reduced. X‐ray diffraction pattern remained the same upon irradiation but a decrease in relative crystallinity was observed with increasing irradiation dose. Gelatinisation temperature and enthalpy decreased significantly when the increasing the dose of gamma irradiation.     

Effect of insecticidal atmosphere and low dose X‐ray irradiation in combination with cold quarantine storage on bioactive compounds of clementine mandarins cv. ‘Clemenules’

Citrus fruits are a rich source of vitamins and polyphenolic compounds with antioxidant capacity that need to be maintained during postharvest storage. The aim of this study was to determine the effect of two innovative quarantine treatments, such as insecticidal atmospheres (IA) (95% CO₂ and balance air) applied at 20 or 25 °C for 20 h and low doses X‐ray irradiation (0, 30, 54 and 164 Gy), in combination with short periods of cold‐quarantine storage on the nutritional quality of ‘Clemenules’ mandarins. Mandarins were stored at 1.5 °C for 6, 9 or 12 days before the application of IA treatments or for 0, 6 or 12 days after the X‐ray radiation. Nutritional quality of mandarins was determined after the corresponding combination of quarantine treatment (IA or X‐ray) with cold quarantine followed by a shelf life period of 7 days at 20 °C to simulate shelf life conditions. Cold quarantine treatment combined with IA or with X‐ray radiation did not affect negatively total antioxidant capacity and total ascorbic acid content of ‘Clemenules’ mandarins. However, flavanone glycosides (FGs) and total phenolics content were slightly modified. Application of the IA at 20 °C induced a greater inhibition of the FGs than application at 25 °C. When X‐ray irradiation was applied without a previous quarantine period the synthesis of the FGs increased as irradiation dose increased.     

Influence of fat replacers on the chemical,textural and sensory properties of low‐fat Beyaz pickled cheese produced from ewe's milk

In this study, low‐fat Beyaz pickled cheeses were produced from ewe's milk using a protein‐based fat replacer (1.0% w/w Simplesse^®), a carbohydrate‐based fat replacer (0.5% w/w Maltrin^®) and a blend of both (0.5% w/w Simplesse^® + 0.25% w/w Maltrin^®). The chemical, textural and sensory properties of cheeses were examined during storage for 60 days. The use of fat replacers affected chemical (except pH and acidity), textural and sensory properties of the cheeses. The cheeses produced with Simplesse^® (Sample B) were similar to full‐fat cheese and had the highest sensory scores.     

Effect of previous frozen storage on quality changes of grass carp (Ctenopharyngodon idellus) fillets during short‐term chilled storage

The effect of chilled, frozen and freeze‐chilled storage on quality of grass carp fillets and soups was evaluated by sensory score, total aerobic counts and biochemical quality. Fish fillets were stored at 4 °C for 6 days (T1), ?40 °C for 12 h and then at ?20 °C for 5 days (T2), ?40 °C for 12 h and then at ?20 °C for 5 days, followed by at 4 °C for 4 days (T3). T1 showed higher sensory score, salt‐soluble protein content, better colour and texture qualities than T2 and T3 within 3 days. All fillets kept good quality based on the acceptable limit of sensory score, total volatile basic nitrogen and total aerobic count during storage time. According to the transportation and retail time, chilled storage is appropriate when it is within 3 days. If it extends for 5 days, freeze‐chilling treatment keeps better quality, but later chilled fillets should be retailed within 4 days.     

Utilisation of fruit fibres in conventional and reduced‐fat cooked‐meat sausages

The effect of several fruit dietary fibres on the sensory properties of conventional and reduced‐fat cooked‐meat sausages is studied. Fruit fibres were assayed at 15 and 30 g kg^?1 concentrations. The energy value reduction of the final products was close to 30%. Instrumental measurements of colour and texture were performed. Sensory properties were estimated by hedonic tests. A correlation principal component analysis was performed. The results of textural analysis showed that the differences between batches were mainly related to the fat content. However, sensory analysis indicated that the most appreciated batches were those manufactured with orange fibre, although their colour was more yellow than the remainder. As a consequence, it is possible to manufacture conventional and hypocaloric cooked sausages containing fruit fibres mainly at a concentration of 15 g kg^?1 of fibre and obtain a sensorial acceptable product. Copyright © 2006 Society of Chemical Industry     

Gluten‐free bread: multiple time–intensity analysis,physical characterisation and acceptance test

The formulation of gluten‐free breads is challenging, once the gluten network is responsible for the physical and sensory properties of bread. This study presents a novel concept for making gluten‐free breads using sugar substitutes. The quality of gluten‐free breads was analysed by means of physical (specific volume and colour), textural (firmness, elasticity and chewiness) and sensory properties (time‐intensity analysis and acceptance test). Time‐intensity analysis showed that the sample developed with raw sugar had a higher intensity of sweetness, and the sample with stevia had a higher intensity of yeast flavour. The sample with frutooligosaccharides (FOS) presented a higher acceptance by consumers. Sample with stevia presented the higher intensity of yeast flavour (8.10) and the lesser mean of specific volume (2.83 cm³.g^?1); whereas sample with sugar who presented higher intensity of sweetness stimulus (5.20) also presented the higher mean of specific volume (3.80 cm³.g^?1). The addition of prebiotic and sweetener opens up new opportunities to develop gluten‐free breads that may present similar properties to those of wheat‐based breads.     

SENSORY QUALITY AND NUTRIENT COMPOSITION OF THREE HAWAIIAN FRUITS TREATED BY X-IRRADIATION

Papayas, rambutans, and Kau oranges were irradiated at 0 (control) and 0.75 (irradiated) kGy and stored for 2 and 9 days to determine the effect of X‐irradiation on objective and sensory quality attributes. Irradiation at 0.25 kGy, as a minimum dose, has been approved as a quarantine treatment for the export of tropical fruits grown in Hawaii. The effects of irradiation and storage on specific sensory attributes were dependent on the specific fruit. Aroma and flavor tended to be more intense in the irradiated fruit. Firmness decreased as a result of irradiation and storage, though significant only in rambutans. The color of the rambutans and oranges were significantly affected by irradiation. Irradiation did not contribute to significant changes in the ascorbic acid and carotenoid contents, pH, titratable acidity, and total soluble solids. Adaptation of X‐ray irradiation as a quarantine treatment should enhance the marketability of tropical fruits.     

Proteolysis,Texture, and Sensory Characteristics of Serrano Hams from Duroc and Large White Pigs during Dry‐Curing

Proteolysis, texture, physicochemical, and sensory characteristics of Serrano hams from Duroc and Large White pigs at 5, 7, 9, 12, and 15 m of curing (3 hams per breed per curing time) were investigated. Higher concentrations of some sarcoplasmic and myofibrillar proteins, peptides with molecular mass in the ranges 3700 to 12000 Da, 700 to 2000 Da, and below 450 Da, and total free amino acids were recorded for Large White hams, while hydrophobic peptides were at higher levels in Duroc hams. A 40 kDa peak in the low‐ionic‐strength soluble protein fraction and 2 peaks of 40 and 45 kDa in the high‐ionic‐strength soluble protein fraction found only in Duroc hams could be of use in discriminating products from different breeds. Physicochemical and textural characteristics of both types of hams evolved similarly during curing and differences in organoleptic traits between breeds were negligible. Flavor intensity and flavor quality of hams were strongly correlated to curing time, with r² values over 0.95 for flavor intensity and over 0.90 for flavor quality, and to the concentration of total free amino acids, with r² values over 0.90 for both flavor intensity and flavor quality. The sensory evaluation scores of Duroc hams, at least as high as those of Large White hams, make the production of high‐quality Serrano ham from pure breed Duroc pigs feasible. Practical Application: Duroc breed crosses are advantageous in the production of dry‐cured hams, resulting in higher marbling, enhanced flavor and lower processing losses, but the characteristics of pure breed Duroc hams have not been investigated. The similar evolution of the compositional, proteolytic, textural, and sensory characteristics of Serrano hams from Duroc and Large White pigs during dry‐curing recorded in the present work makes the production of high‐quality dry‐cured hams from pure breed Duroc pigs feasible. Three protein peaks found only in Duroc hams can be of use to discriminate products from different breeds.     

Quality characteristics of a non‐fermented dry‐cured sausage formulated with lemon albedo

Dry‐cured sausages were treated with two types of dehydrated lemon albedo (raw and cooked) at five concentrations (0–100 g kg^?1 in 25 g kg^?1 increments). Several physical and chemical analyses were made during the drying stage, and compositional, textural and sensory analyses were conducted on the finished products. The addition of albedo improved the nutritional properties as a result of fibre addition and may have beneficial effects due to the presence of active biocompounds as evidenced by a decrease in residual nitrite levels and delayed oxidation (based on TBARS values). The sensory properties of samples that resembled the control sausages were those that contained up to 50 g kg^?1 dehydrated raw albedo and 75 g kg^?1 dehydrated cooked albedo. Copyright © 2004 Society of Chemical Industry     

Ready‐to‐eat snack products: the role of extrusion technology in developing consumer acceptable and nutritious snacks

Consumer appeal for ready‐to‐eat (RTE) products is forecast to grow rapidly over the next 5 years as consumers demand convenient snacks with exciting sensory and textural properties. Extrusion technology has been used extensively in the production of cereal RTE snacks due to its ease of operation and ability to produce a variety of textures and shapes which appeal to consumers. Many of the existing RTE products are relatively high in sugar and salt, thus being regarded as energy dense but nutritionally poor foods. However, there exists a potential to manipulate the nutritional status of extruded RTEs by altering the digestion potentials of starch and protein, and by the incorporation of bioactive components such as dietary fibre. The review article explores some of the recent research in this field and illustrates opportunities by which the global food industry could react to consumers' requirements for healthful RTE snack products in the coming years.     

Effect of durum wheat varieties on bread quality

In this study, the effect of different durum wheat varieties on the sensorial and nutritional quality of bread was assessed. In particular, bread manufactured with six wheat cultivars was compared with bread based on commercial semolina mixtures. X‐ray microtomography was used to characterise the final cellular structure of the baked bread. The textural properties of baked bread and doughs were also investigated. In addition, the glucose equivalent (GE) of bread was also evaluated. Finally, the microstructural, sensorial and textural parameters were correlated with each other. Results highlighted that Cappelli and Saragolla bread samples showed higher protein and total soluble fibre content, respectively, in comparison with the reference samples. Moreover, the GE of the Cappelli, Claudio and Saragolla bread samples was similar to that of the reference samples and lower than that of the other samples. However, the sensorial properties of all bread samples showed a very positive score (up to 7.7).     

Optimisation of the combined treatments of aqueous chlorine dioxide,fumaric acid and ultraviolet‐C for improving the microbial quality and maintaining sensory quality of common buckwheat sprout

The effects of the combined treatments with aqueous chlorine dioxide (ClO₂), fumaric acid and ultraviolet‐C (UV‐C) on the microbial quality of common buckwheat sprouts were examined using a response surface methodology. The populations of total aerobic bacteria, yeast and mould, and coliform decreased with increasing aqueous ClO₂ and fumaric acid concentrations and increasing UV‐C irradiation dose. However, the increase in the UV‐C irradiation dose had a negative effect on the sensory quality. Therefore, the optimal combined treatment condition of 100 ppm aqueous ClO₂, 0.31% fumaric acid and 1.9 kJ m^?2 UV‐C was selected for the buckwheat sprouts by providing reductions of 3.9, 1.8 and 2.4 log CFU g^?1 on the populations of total aerobic bacteria, yeast and mould, and coliform, respectively. The combined treatment also maintained an acceptable sensory quality. These results suggest that the optimised combined treatment can be used as a microbial inactivation method for buckwheat sprouts.     

Quality and safety of irradiated food regarding biogenic amines: Ras cheese

Food safety and quality became very important, especially with the challenge to ensure safe and healthy foods in regard to chemical hazards. So, this study was conducted to evaluate the quality and safety of irradiated Ras cheese during the storage period, with respect to biogenic amines (BAs). Ras cheese was manufactured, ripened and irradiated by γ‐irradiation at 0, 5, 10 and 15 kGy. The samples were stored in refrigerator at 5 ± 1 °C from where samples were withdrawn at 0, 2, 4 and 6 months for analysis. The results revealed that most sensory scores and chemical properties showed insignificant differences (P ≤ 0.05). The microbial counts were reduced with different degrees according to both storage period and irradiation dose. Also, irradiation was effective in reducing the content of BAs without harming the chemical properties of Ras cheese. The total content of BAs reflects the safety of irradiated Ras cheese and also indicates a high‐quality product in comparison with nonirradiated samples.     

The effect of pumpkin fibre on quality and storage stability of reduced‐fat set‐type yogurt

In this study, the effect of pumpkin fibre (PF) on physicochemical, microbiological, rheological and microstructural characteristics of reduced‐fat yogurt samples was investigated during storage. PF was added at three different concentrations (0.5%, 1.0% and 1.5%) to standardised (1.55% fat ratio) cow's milk. Plain yogurt (PF‐free) was used for comparison. The addition of PF significantly affected total solid content, synaeresis, water‐holding capacity, apparent viscosity and colour parameters (L*, a*, b*) of yogurt samples for all sampling time. The addition of PF caused a reduction in L* values (from 94.89 to 88.67), but caused an increase in a* (from ?2.10 to +4.22) and b* (from 10.79 to 25.88) values. Yogurts with PF exhibited lower synaeresis and more viscous structure than PF‐free sample during storage. SEM images showed that distinctive microstructure profile was present between samples with or without PF. More filamentous structures and denser network were observed in the SEM images and these increased with increasing level of PF. Yogurt containing 1.0% PF showed a higher storage (G′) (3687.87 at 21 day) and loss (G″) (543.10 at 21 day) moduli in comparison with other samples. In conclusion, the results revealed that PF improved the physical quality and contributed textural properties of half‐fat yogurt.