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关键词： Digital storage  

摘要： This study investigated the impact of sugar reduction on the physicochemical properties (pH, water activity (a(w)), total soluble solids (TSS), viscosity, and color) and microbial safety (total mesophilic and psychrotrophic bacteria, yeast and mold, total coliform, Escherichia coli, and Listeria monocytogenes) of chocolate-flavored milk stored under refrigeration (4 +/- 1 degrees C) for 28 days. When compared with the full-sugar chocolate milk (control), the 50% reduced-sugar (w/v) formulation containing concentration of stevia (56.27 mg/L) and monk fruit extract (81.90 mg/L), optimized based on the sensory responses by 107 consumers, showed no significant changes in pH, a(w), and microbial growth. However, TSS and viscosity were significantly lower with higher lightness and yellowness but lower redness values in the reduced-sugar sample compared to the control, but no significant changes were observed over the storage period. Consequently, 50% of added sugar (w/v) could be reduced to formulate chocolate milk with acceptable physicochemical properties and microbial safety. Practical applications Flavored milk is a source of recommended dietary allowances for vitamin D and calcium but can contain up to 10% of added sugar (w/v). However, the intake of high levels of added sugar has been associated with several chronic diseases. Hence, there is a need to reduce added sugar. But the impact of sugar reduction has mainly been investigated from a health perspective. There is limited data available on how this impacts physicochemical and microbial properties. These aspects are crucial to be assessed before the new product could be launched in the market. Hence, the findings from this study will provide insights to the dairy industry on the stability of a new product in terms of physicochemical and microbiological safety when considering sugar reformulation programs.

关键词： Physicochemical properties  

摘要： In view of the nutritional and sensory aspects of thyme (Thymus vulgaris), it can be added as a functional ingredient to extend the shelf life of food products. Thyme leaves powder (TLP) at different concentrations (1%, 3%, 5%, and 7%) with wheat flour in cookies formulation was added. Physicochemical composition and sensory attributes of cookies at storage intervals of 0, 15, 30, and 45 days were studied. All the properties of cookies affected significantly. During storage, TLP had a nonsignificant effect on chemical composition of cookies except moisture. There was no significant change for physical properties of cookies but fracturability, hardness, and water activity showed changes during storage. Color of cookies (L*, a*, and b*) varied from 57.79 to 42.64, 12.82 to 3.37, and 23.29 to 17.82, respectively, but storage did not affect the color. Cookies with 3% TLP were most preferred with respect to organoleptic characteristics by judges. Practical applications The present study can not only endorse the nutritional characteristics and sensory evaluation of thyme leaves powder cookies but also guide the overall community concerning the significance of thyme herb. In future, research on application of thyme in various food industries with its more striking benefits regarding safety and quality is required.

关键词： Starches   Flours   Physicochemical properties   Roots and tubers  

摘要： Underutilized roots and tuber crops have the potential to commercialize and contribute to the regular diet of the consumers. These crops provide several nutrients and health benefits, besides, to serve as major sources of carbohydrates. This study was aimed to characterize the flours and starches of Dioscorea alata (Kahata-ala-KA and Hingurala-H), Dioscorea esculenta (Java-ala-JA), Lasia spinosa and Nelumbo nucifera concerning compositional, functional and morphological parameters. The composition of carbohydrates, starch granular morphology and functional properties of selected roots and tubers were analyzed. The total dietary fiber and resistant starch contents were in the range of 6.83 +/- 0.66-39.42 +/- 0.74% and 4.65 +/- 0.56-9.54 +/- 0.71 respectively on a dry weight basis. The shapes of starch granules of D. alata, D. esculenta, L. spinosa and N. nucifera were spherical, polygonal, elongated and round to elongate respectively. There were considerable variations in total starch, total dietary fiber, resistant starch, amylose and amylopectin, water holding capacity, oil holding capacity, swelling power, water solubility and gelatinization parameters among five varieties. All tested varieties showed a considerable amount of dietary fiber and resistant starch contents that could lead to health benefits along with preferable functional properties that favorable for food product formulation.

关键词： Extrusion  

摘要： The utilization rate of oat bran was improved and wastage of resources was reduced using the micro-pulverization technology combined with extrusion in processing oat bran. The effects of micro-pulverization and extrusion treatment on the structure, color, physical and chemical properties, functional properties, and pasting properties of oat bran were evaluated via Fourier transform infrared spectroscopy, scanning electron microscopy, colorimeter, and rapid viscosity analyzer. Results showed that the pulverization and extrusion did not produce new functional groups in the bran. However, both treatment methods could increase the content of soluble dietary fiber and degree of starch gelatinization, reduce oil-holding capacity, and increase water solubility index. Micro-pulverization increased the brightness and slowly digestible starch of the bran, reduced rapidly digestible starch (RDS), and enhanced the antioxidant capacity of oat bran. Conversely, extrusion reduced the brightness and antioxidant capacity of oat bran, increased RDS. And extrusion made the surface of the bran relatively flat and denatured the protein. This study provides a theoretical basis that enterprises involved in oat processing can refer to. According to different market needs, adopt appropriate processing methods to process oat bran in order to gain more oat bran products. Novelty impact statement Micro-pulverization and extrusion had a great influence on the physical and chemical properties of oat bran. Some indicators (such as anti-oxidation, color) had completely opposite results with two treatments. micro-pulverization did not change the functional groups of bran, did not affect its beta-glucan content, but reduced its IDF content.

关键词： Dough rheology   Bread texture analysis   Starch retrogradation   Bread staling   FTIR analysis   Sensory evaluation  

摘要： Wheat flour was substituted by flour from roasted chickpeas at 10-20% (flour basis) and a multi-instrumental analytical approach was employed to explore the dough rheological behavior of the composite starch-proteins hydrated networks, the quality attributes of the resultant breads, as well as the staling process. Fortifications with roasted chickpea flour at 15 and 20% level significantly increased dough viscosity and elasticity as showed by oscillatory and creep-recovery rheological tests, implying higher dough resistance to flow and deformation that resulted in breads with significantly lower specific volumes and harder crumb than the control (bread without chickpea flour). Moreover, at 20% substitution level, the staling kinetics of composite breads, as monitored by texture profile analysis, indicated a greater extent of crumb hardening at the end of storage, whereas the level of retrograded amylopectin in the crumb as assessed by calorimetry (DSC) did not differ among samples. Nevertheless, for bread with 20% chickpea flour, FTIR spectroscopy revealed a large increase in protein beta-sheets and a further increment of such conformational change in the stored crumb, suggesting dehydration of gluten and its involvement in the staling process. Instead, formulations with 10% roasted chickpea flour did not exhibit any major influence on dough rheological behavior, as well as on textural attributes and bread staling. Furthermore, at 10% substitution of wheat flour by roasted chickpea flour, there was complete masking of the "grass-like" and reduced "beany" and "earthy" off-flavor notes in breads, as assessed by a trained panel, pointing to a product with high overall acceptability.

关键词： Starch  

摘要： Increasing metabolic disorders and changing lifestyles have created an increased demand for healthy convenience food, especially breakfast. The study aims to identify an ideal processing method to formulate a ready-to-cook savory wheat (Dalia) porridge with reduced starch digestibility and enriched protein and fiber content. Pressure cooking (WP), autoclaving (WA), drum drying (WD), flaking (WF), and toasting (WT) were adopted for instantization. The energy distribution was as per the guidelines of the American Diabetes Association. Processing resulted in reduced cooking time, changes in color parameters, increased water absorption, and solubility. Complete gelatinization of starch was observed in all samples except WA and WT. Resistant starch content increased in all samples (8.95-16.70 g/100 g) except WD and WT. The estimated glycemic Index (eGI) ranged from 65.8 to 54.8, with maximum eGI shown by WD and minimum by WA. Increase in vitro protein digestibility 5%-10% was observed. All the porridge showed good sensory characteristics and acceptability. Practical applications Breakfast is considered as a crucial meal of the day in a healthy lifestyle. Skipping or consuming a nutritionally imbalanced hunger sufficing breakfasts has been increasing due to changing work cultures and time lack for cooking which is attributed to increasing metabolic diseases. Thus, the development of a healthy convenience breakfast has acquired great attention. In this study, the interaction between protein, fiber, starch, and fat has been utilized in formulating a low GI ready-to-cook (RTC) breakfast mix with the energy distribution as suggested by the American Diabetic Association for diabetes. The RTC breakfast mix with modulated eGI will cater to the needs of diabetic, obese, and elderly population. The product will have good compliance, as it is prepared with the staple ingredients and GI is modulated using natural ingredients and can be scaled up with minimum operating steps for comm

关键词： Microalgae   Extraction   Techno-functional properties   Emulsifying properties   Rheological behaviour  

摘要： Microalgae are a promising and sustainable ingredient for functional food development, due to their rich nutritional and health-promoting effects. Moreover, microalgae generally contain large amounts of structural biopolymers such as proteins and polysaccharides, which might display interesting technological features and rheological properties. This study aims at unravelling Phaeodactylum tricornutum extracts (PTE) potential role as structuring agents for food applications. Distilled water and a mixture of water/ethanol (75/25, v v(-1)) were used as solvents. Extracts' physicochemical properties were analysed regarding protein folding, molecular weight distribution, polymer interactions, and their main functional groups. PTE thermal properties, rheological behaviour, and emulsifying capacities were also evaluated. PTE showed different gelling mechanisms, with 40 degrees C aqueous purified extracts reporting the strongest gel character. Moreover, 80 degrees C ethanolic purified extracts showed the greatest emulsifying potential, with an initial emulsification index (EI) of around 90%. This EI decreased to 60% after 10 days, but remained constant for the following 15 days, showing an interesting emulsion stability. Overall, these findings suggest that PTE have a great potential for further application as thickening or emulsifier food ingredients. This diatom revealed to be a valuable source of structurally diverse, technologically active compounds.

关键词： Food products  

摘要： This work describes the functional and nutritional quality of the flour of 10 common beans to verify their potential for application as ingredients in food products. Bean flours were prepared from seven carioca and three colored bean grains. The higher content of protein (25 g center dot 100 g(-1)), fat (1.5 g center dot 100 g(-1)), and low carbohydrate (55 g center dot 100 g(-1)) was found in the pink bean. The purple bean presented the highest phenolic content (54.47 mg center dot g(-1)), anthocyanins (76.4 mu g center dot g(-1)), and antioxidant activity (21.17 mu mol Trolox center dot g(-1)). The carioca bean flour presented a low content of phytates (4.84 mg center dot g(-1)) and tannins (0.0 mg center dot g(-1)). Concerning the pasting properties, the bean flour presented a high variation for the final viscosity (227-1,934 cP), setback (147-596 cP). For water solubility and emulsification capacity, carioca bean showed high values (28 g center dot 100 g(-1) and 59%, respectively). The aged bean flours may be suitable for various food applications due to their variability in nutritional composition and technological parameters. Practical applications We have obtained flours from different aged common beans. Our interest is to expand the use of aged beans as an ingredient (i.e., as flour) by showing its functional and nutritional properties as well its potential for use in various food systems. We show that the aged bean flour presented a potential for application as an ingredient in food products (e.g., soups, creams, pasta, and others). Additionally, bean flours may permit the development of food products with nutritional appeal since beans are an important source of nutrients.

关键词： farinograph property   fresh wet noodles   microbial decontamination   microstructure   non-thermal plasma treatment   polyphenol oxidase activity  

摘要： The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products.

关键词： Indica rice   Branching enzymes   Starch chain length distribution   CRISPR   Cas9  

摘要： Key message Down-regulation of starch branching enzymes alters fine structure and starch properties, especially the B-type crystalline pattern and extremely high amylose content identified in the BEIIb-deficiency mutant in the indica rice. The relative importance of the starch branching enzymes in determining the molecular fine structure and starch functional properties were uncovered in this study. An indica rice, Guangluai 4 with high amylose content (AC) and high gelatinization temperature (GT) was used to generate the clustered regularly interspaced short palindromic repeats (CRISPR)/associated protein-9 (Cas9) knockout lines. Five mutant lines were identified including be1-1, be1-2, be2a-1, be2a-2 and be2b-1, and analysis of western blot showed the CRISPR/Cas9 system was successful in inducing mutations in the targeted genes. AC of be2b-1 (34.1%) was greater than that of wild type (WT) (27.4%) and other mutants. Mutations of either BEI or BEIIa did not alter the starch crystallite pattern (A-type). The BEIIb deficiency caused an opaque endosperm phenotype, changed the crystallite pattern from A- to B-type, and dramatically increased the degree of ordered structure, the relative proportion of amylose chains and intermediate to long amylopectin chains, average chain length of amylopectin molecules as well as GT. The BEIIa deficiency had no effect on the proportion of amylose chains, the length of amylopectin intermediate-long chains, conclusion temperature and enthalpy of gelatinization. Down-regulation of BEI increased the proportion of shortest amylopectin chains (fa) but decreased the proportion of long amylopectin chains (fb2 and fb3), leading to a lower GT. It is concluded that the relative importance in determining starch fine structures and functionality was in the order of BEIIb > BEI > BEIIa. Our results provide new information for utilizations of BE-deficient mutants in rice quality breeding.