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1.
Preliminary experiments have been carried out to determine the uptake of lead from both hard and soft waters used in the preparation of food and beverages. Lead concentrations in water for the range of 0.05-0.5 mg litre?1 were used to prepare composite groups representing root vegetables, other vegetables and beverages whose composition reflected per capita consumption of these foods in the UK. The uptake of lead from water was highest for the composite group of other vegetables which comprises 70% by weight of green vegetables. For each of the composite groups and the particular water samples used there was little relative difference in uptake whether foods were prepared in hard or soft water. Calculations of the contribution made by lead in water used for preparation of foods and beverages to the total dietary lead intake indicates that at levels of lead of 0.02 mg litre?1, the contribution is about 10% but this can rise to about 40% as lead levels in the water approach 0.1 mg litre?1.  相似文献   

2.
The effect of cooking water on both textural and cooking properties of spaghetti was investigated for spaghetti samples, which differ in protein content. The samples were analysed after cooking in deionised, laboratory tap water, deionised water with 2.5% salt and deionised water with 5.0% salt. Brands A, B, and C were usual durum wheat spaghetti and brand D was spaghetti enriched with bran. Regardless of the cooking water used, brand D had higher hardness and lower adhesiveness than other spaghetti samples and required longer cooking time to achieve optimum cooking. It was found that samples cooked deionised water had lower hardness and adhesiveness values as compared to samples cooked in salty water. It can be concluded that a certain amount of salt in the cooking water improves textural characteristics of cooked pasta.  相似文献   

3.
The effects of extrusion temperature (80, 90 and 100 °C) and flour moisture content (27%, 31% and 35%) on corn spaghetti quality were evaluated according to a factorial experimental design. Flours obtained from a soft and hard endosperm were processed in a Brabender single screw extruder. Corn spaghettis with good cooking characteristics and resistance to overcooking were obtained by extrusion at 27% flour moisture content for the three temperatures used. They have higher resistance to hydration, long cooking time (around 11 vs. 7 min for poor quality) and low cooking loss (lower than 9% for a 10‐min overcooking). Softer endosperm allowed obtaining better spaghetti quality. Among different physicochemical properties, enzyme susceptibility could be used as an indicator of mechanical energy dissipated by friction. During extrusion cooking, the native structure is partially destroyed, and new crystalline ones, corresponding to the amylose–lipid complex, are formed.  相似文献   

4.
The effect of cooking water on textural and cooking properties of spaghetti was examined using four different salt concentrations 0, 1, 2, 3 and 4% in the cooking water and two types of spaghetti. Brand A was normal durum wheat spaghetti and brand B was spaghetti enriched with bran. Regardless of the cooking water used, brand B was harder, less sticky than brand A and it absorbed less water. Brand A required less cooking time. As salt concentration increased cooking time and hardness scores increased. Adhesiveness values were highest at the early stages of cooking and declined as cooking time increased.  相似文献   

5.
Spaghetti was made from two Italian durum wheat varieties and cooked for 10, 15 and 20 min. Percentages of water absorption and cooking loss were determined. Measurable amounts of soluble nitrogen, starch, minerals and vitamins were found in the water used for cooking.
Minerals and vitamins were determined in cooked spaghetti. The percentage reduction of metals increased with increasing cooking time, but trace elements decreased after 10 min of cooking and then became stable at the longer times. It is preferable to cook spaghetti for 15 min.  相似文献   

6.
An experiment was conducted to determine the effect of different pasta:water ratios and nontraditional ingredients on the cooking properties of spaghetti. Spaghetti was made using semolina and semolina containing 20% (w/w) nontraditional (NT) ingredients (corn, flaxseed, lentil, oat, pinto bean and soybean flours). Pasta:water ratios evaluated were 13 g:400 mL, 27 g:400 mL and 48 g:400 mL. Addition of pasta caused a decline in cooking water temperature. The water temperature drop and recovery time to boiling (100 °C) varied with pasta:water ratio and with nontraditional ingredient in the spaghetti. These results were attributed to the calculated specific heat capacity of the ingredients incorporated in the spaghetti. Cooking time was reduced for all NT spaghetti with respect to the control sample and was longest when 48 g of pasta was cooked. Pasta:water ratio affected cooking loss but not cooked weight or cooked firmness. Cooking losses were greater with 13 g:400 mL compared to 48 g:400 mL.  相似文献   

7.
The aim of this work was to analyse some nutritional characteristics in eatable vegetables obtained by conventional and organic grown culture, focusing on vegetable parts that are generally rejected by consumers. Samples of Chinese cabbage ( Brassica rapa (syn. B. campestris ) spp. pekinensis )) and maize ( Zea mays L.) had been analysed under raw conditions and after thermal treatment in order to test modifications in protein, lipids, carbohydrate, phenol, nitrate content and dry weight. According to our results, thermal treatment modified some characteristics. Even if for most parameters significant differences between foods obtained by the two cultivation procedures had not been observed, in organic samples a higher concentration of nitrate was found. Furthermore, domestic processing, such as cooking in boiling water, seems to have a dramatic effect on phenolic content on both kinds of food, and, as a consequence, on antioxidant activity.  相似文献   

8.
Research was conducted to determine the effect of processing and cooking on the ash content and mineral composition and on protein content and amino acid composition of spaghetti that was fortified with 250 g kg?1 buckwheat bran flour (BBF). Extrusion and drying temperature had little or no effect on ash and mineral content of spaghetti containing BBF. Drying temperature did not affect protein content; however, a 31% reduction in lysine content was observed in spaghetti containing BBF dried at 90 °C. Cooking spaghetti fortified with BBF reduced ash content by 28%. Reduction in ash content was reflected by an average decrease in potassium of 62%, in copper of 45%, and in zinc of 11%. Cooking had little or no effect on content of calcium, iron, magnesium, or manganese. As a result of material leaching from spaghetti during cooking, the protein content and content of each amino acid (db) were greater in cooked than uncooked spaghetti. Copyright © 2007 Society of Chemical Industry  相似文献   

9.
Spaghetti was processed in a semi-commercial scale laboratory press from a range of raw materials, dried by a low temperature (LT) and a high temperature (HT) drying cycle, and assessed for stickiness and other important cooking quality attributes in cooking waters of varying hardness. Cooked HT spaghetti was generally less sticky, more resilient, firmer, and exhibited lower cooking loss than corresponding LT spaghetti. As cooking water hardness increased spaghetti became stickier and cooking loss increased. Stickiness was influenced by cultivar, wheat class, raw material granulation and protein content, but was not related to sprout damage. Stickiness was significantly correlated to cooking loss, cooked weight, degree of swelling, compressibility, recovery, and firmness. However, even when all these factors were included in a step-up regression less than 50% of the variance in stickiness could be predicted.  相似文献   

10.
小麦粉品质和制面工艺对面条品质的影响研究   总被引:21,自引:5,他引:21  
以普通小麦为原料,以非传统细条实心面条为对象,研究了挤压温度,食盐含量及小麦粉品质对细细条实心面成品品质的影响。结果认为,升高加工温度,可以降低挤压阻力:提高食盐含量,增加挤压阻力。提高温度和食盐含量,都能增加面条的蒸吸水率和蒸煮干物质失落率。温度对面条蒸煮蛋白质的损失率影响较大。样品的蛋白质品质和淀粉的糊化特性对品质也有较大的影响。  相似文献   

11.
邬松恒  刘玉环  崔宪  张琦  王允圃  罗璇 《食品科学》2022,43(16):302-308
研究4种烹饪(油炒、汽蒸、微波和水煮)过程对空心菜和卷心菜中硝酸盐、亚硝酸盐和抗氧化能力的影响,并通过抗氧化性/体内亚硝酸盐比(antioxidant/in vivo nitrite ratio,A/N)值评价其硝酸盐潜在安全风险。结果表明,油炒会同时提升叶类蔬菜的硝酸盐含量(28.03%~49.57%)和铁离子还原能力(108.88%~218.35%),而水煮则相反。微波和汽蒸在降低蔬菜硝酸盐含量(31.25%~46.61%)的同时提升铁离子还原能力(76.35%~112.99%)。基于可食用性和A/N值评价结果,在烹饪2 min内空心菜和卷心菜分别选择水煮和油炒烹饪对硝酸盐潜在安全风险的控制效果更好。微波是两种叶类蔬菜相对安全的烹饪方式,但不宜超过4 min,而汽蒸更适宜长时间烹饪(>4 min)。  相似文献   

12.
The cooking quality of pasta based on soft wheat flour and supplemented with three percentages of oat flour was studied. Results showed that oat flour modified deeply the cooking quality of spaghetti in comparison with samples based on only soft wheat flour. These effects were attributed to both starch‐lipid complex formation and presence of β‐glucans that weak gluten network. An increase in optimal cooking time with increase in oat percentages was observed (480 vs. 630 min). Samples enriched with oat flour showed a good‐quality cooking total organic matter (TOM values ranged from 1.4 to 2).  相似文献   

13.
High Temperature Drying: Effect on Spaghetti Properties   总被引:3,自引:0,他引:3  
The characteristics of spaghetti produced from two high temperature (HT) drying cycles, one featuring HT at the initial stages of drying (HT-A) and one featuring HT during the latter stages of drying (HT-B) were compared to spaghetti produced by low temperature (LT) drying. Both HT cycles had the advantage of greatly reduced drying time. In addition HT-A spaghetti exhibited much enhanced color intensity compared to LT spaghetti. Although HT-A spaghetti cooking properties were marginally inferior to LT spaghetti, cooking quality was still satisfactory. Spaghetti from HT-B was equal to or better than LT spaghetti in color quality while also exhibiting improved strand strength and superior cooking properties.  相似文献   

14.
A. Baiano  C. Lamacchia  C. Fares  E. La Notte 《LWT》2011,44(4):1226-1232
The effects of the replacement of increasing amounts of semolina with toasted or partially defatted soy flour on dough rheological indices and spaghetti quality were evaluated. The replacement caused the dough weakening and the increase of the tenacity-extensibility ratio. Due to the competition of soy proteins and starch for water, the substitution of increasing amounts of semolina was able to increase the optimal cooking time without significant changes of the ratio between the increase in weight or diameter and the weight or diameter of dry spaghetti (ΔP/P and ΔD/D) but with a significant slowing of the ΔL/L (ratio between the increase in length and the length of dry spaghetti) increase during overcooking. Around the optimal cooking time, the release of organic matter was higher in pasta made exclusively of semolina whereas the sensory response was similar for control and composite spaghetti. Statistically significant correlations were obtained between protein content of the flour mixtures or dough alveographic indices and the cooking behaviour of semolina-soy spaghetti according to non-linear regression models. In particular, both protein content and alveographic indices allowed to predict approximately 92-94% of the variation of cooking losses and, in a lower measure, the variation of bulkiness and elasticity of semolina-soy spaghetti.  相似文献   

15.
The extent of phytate degradation in breads and various foods consumed in Saudi Arabia was followed after baking or cooking. Phytate phosphorus content in raw and baked or cooked food was determined by ion-exchange and colorimeteric methods. White bread containing soda, namely Tamees, had a lower degree of phytate degradation followed by pita brown bread, namely Burr, in comparison to pita, French and pan white breads not containing soda, namely Mafrood, Samouli and Toast, respectively. The phytate content in breads ranged from 0.11 to 0.2 8%. Wheat-based food made from whole wheat flour, namely Margoog, had a lower degree of phytate degradation in comparison to other wheat-based foods made from bulgur, grits and partially debranned grains, namely Kibbah, Gerish and Harees, respectively. The phytate content in these foods ranged from 0.08 to 0.25%. Rice-based foods made from parboiled rice, namely Kabsa, or not drained from steeping or cooking water, namely Saleeg, had a lower phytate degradation than rice drained from steeping or cooking water, namely Baryani or Rus Abiedh. The phytate content in these foods was lower and ranged from 0.04 to 0.1%. Similarly, faba beans-based food not drained from cooking water, namely Food Jerra, had a lower degree of phytate degradation than faba bean or chick pea-based foods drained from cooking water, namely Foul Mudames, Falafe and Balila. The phytate contents in these foods ranged from 0.11 to 0.4%. Food recipes and baking conditions or cooking procedures are the main factors that affect the extent of phytate degradation. To avoid adverse effects on mineral nutrients, reduction in the phytate content of the phytate-rich foods such as Burr bread, Margoog and Foul Jerra foods, is recommended.  相似文献   

16.
Deoxynivalenol (DON) is a toxic natural metabolite produced by Fusarium graminearum. In this study we investigated the effects of sodium bisulfite and extrusion cooking under high temperature and pressure on DON levels in wheat grain and mill fractions. Samples of highly naturally DON-contaminated soft winter wheat were soaked for 1 h in water or aqueous sodium bisulfite (SB) solutions (0.5, 1.5, 2.5, or 5% SO2 equivalent) and extruded. The soaking treatment with SB solution (5% SO2 equivalent) lowered DON from 7.3 microg/g to 0.8 microg/g without extrusion and to 0.3 microg/g with an extrusion process. When the contaminated kernels were tempered with water or SB solutions (5 or 10% SO2 equivalent) and milled, the flour samples, as expected, showed lower levels of DON (from 7.3 to 3.1 microg/g). Extrusion of milled flour and whole meal samples, both obtained from SB-tempered wheat, did not change DON levels significantly under the studied extrusion conditions as compared to the nonextruded milled flour and whole meal samples. However, the extrusion process can be utilized to remove moisture and/or odor of chemicals used in the soaking solutions and to produce potentially useful extruded products.  相似文献   

17.
18.
Six samples of semolina, milled from durum wheats of varying quality, were extruded through Teflon and non-Teflon lined dies. Extruded spaghetti was evaluated for color and cooking quality. The effect of cooking time on cooking quality was also evaluated. Teflon extruded spaghetti had better appearance and cooking quality than its non-Teflon extruded counterpart. Strong gluten, whether in the Teflon or non-Teflon extruded products, improved cooking quality and tolerance to over-cooking. Scanning electron microscopy of the outer surface of dry and cooked spaghetti elucidated, in part, the differences in appearance and cooking quality of the products extruded through both die forms.  相似文献   

19.
BACKGROUND: Microalgae are able to enhance the nutritional content of conventional foods and hence to positively affect human health, due to their original chemical composition. The aim of the present study was to prepare fresh spaghetti enriched with different amounts of microalgae biomass (Chlorella vulgaris and Spirulina maxima) and to compare the quality parameters (optimal cooking time, cooking losses, swelling index and water absorption), chemical composition, instrumental texture and colour of the raw and cooked pasta enriched with microalgae biomass with standard semolina spaghetti. RESULTS: The incorporation of microalgae results in an increase of quality parameters when compared to the control sample. The colour of microalgae pastas remained relatively stable after cooking. The addition of microalgae resulted in an increase in the raw pasta firmness when compared to the control sample. Of all the microalgae studied, an increase in the biomass concentration (0.5–2.0%) resulted in a general tendency of an increase in the pasta firmness. Sensory analysis revealed that microalgae pastas had higher acceptance scores by the panellists than the control pasta. CONCLUSION: Microalgae pastas presented very appellative colours, such as orange and green, similar to pastas produced with vegetables, with nutritional advantages, showing energetic values similar to commercial pastas. The use of microalgae biomass can enhance the nutritional and sensorial quality of pasta, without affecting its cooking and textural properties. Copyright © 2010 Society of Chemical Industry  相似文献   

20.
The physical properties of soft and hard wheat grains, cooked with steam under pressure, were investigated. These included water uptake, rheological properties as observed by modulus of elasticity (E) and maximum compressive contact stress (Smax), color in CIE L*a*b* system and pasting properties by Rapid Visco Analyzer (RVA). Four cooking temperatures (110, 120, 130 and 1408 C) and six cooking durations (20, 40, 60, 80, 100 and 120 min) for each temperature were studied. Water uptake (WU) and rheological properties were analyzed immediately after cooking conditions were achieved. For color and pasting properties, cooked wheat grains were dried at low temperature and ground before analysis. It was found that WU increased proportionally with cooking temperatures and durations. Hard wheat grains tended to absorb more water than soft wheat grains. Both E and Smax decreased rapidly when wheat grains were cooked. Such decreases were found to be more rapid in hard wheat grains. Wheat grains became darker when cooked, resulting in the decrease of L* values and increase of a* and b* values. Cooked wheat grains lost their natural pasting properties compared to uncooked grains, resulting in the decrease of viscosity in their RVA profiles. The experimental data fitted well in second-order polynomial models (p # 0.0001). The built models were sufficiently accurate for most of the studied properties (R2 ranging from 0.58–0.97).  相似文献   

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