Cultivar, Processing, and Storage Effects on Pecan Kernel Color

Pecan kernels of two cultivars (Cheyenne and Wichita) and two trial selections (61–6–67 and 49–1478) were evaluated for color differences before and after processing by three methods (chlorine soak, hot water, and steam) and during 15 wk storage at 21°C and 65% RH. Hunter color values varied significantly among cultivars before processing. Significant cultivar and treatment differences were observed after processing and during storage. Kernels of all cultivars subjected to hot water and steam treatments were darker and redder in color after processing and after all storage times than the control (untreated) kernels and those subjected to the chlorine soak method.     

Freezing Rate and Frozen Storage Effects on Color and Sensory Characteristics of Pineapple Fruit Slices

This study was carried out to evaluate the influence of freezing process (cold room –18°C and air-blast freezer –50°C) and frozen storage (–18°C for 0 to 12 mo) on color and sensory quality of pineapple fruit slices (Smooth Cayenne and Red Spanish cultivars). L, –a and +b color parameters showed differences (P ≦ 0.05) with cultivar, but not with freezing rate. No differences (P ≥ 0.05) were found in sensory analysis (color and appearance) between the cultivars, frozen at different rates, compared to fresh product, or after 1 yr frozen storage. The two cultivars are suitable for freezing.     

Color Stability of Strawberry Jam as Affected by Cultivar and Storage Temperature

The stability of three strawberry cultivars was evaluated for changes in jam color quality during processing and storage at 20°, 30° and 37°C for 200 days. Anthocyanin content was determined by HPLC. The effect of cultivar, processing and storage on jam pigments, instrumental color (L*, a*, b*) and consumer preference were also determined. ‘Oso grande’ jam had the lowest anthocyanin concentration (110 mg/g f.w), higher monomeric pigment degradation during processing and storage, highest pH, least desirable color score from the sensory panel and shortest shelf-life. Similarities were found between jams prepared with ‘Chandler'and Tudla’ cultivars, as well as initial differences in total anthocyanin concentrations (195 and 130 mg/g f.w.).     

RHEOLOGICAL AND TEXTURAL CHARACTERISTICS OF RAW AND PAR-COOKED TAEWA (MAORI POTATOES) OF NEW ZEALAND

The quality characteristics of raw and par-cooked (partially cooked) tubers from four different Taewa cultivars were evaluated and compared with a modern potato cultivar (Nadine). Significant differences in dry matter, starch content, color and specific gravity were observed among the raw tubers from the different cultivars. Moemoe and Tutaekuri Taewa cultivars showed higher dry matter content (21.97 and 21.57%, respectively) whereas the lowest specific gravity of 1.057 was observed for Nadine. Par-cooked chef-ready tubers were prepared from each cultivar and evaluated for quality during 21 days of storage at 4C. Tutaekuri raw as well as par-cooked tubers had higher fracturability and hardness whereas Nadine par-cooked tubers had higher adhesiveness than other cultivars. Rheological parameters such as storage modulus ( G' ), loss modulus and loss tangent (tan δ ) were dependent on the dry matter and starch contents of the tubers. The highest peak G' values of 24,930 Pa and 19,700 Pa were observed for Tutaekuri and Moemoe potato cultivars, respectively.

PRACTICAL APPLICATIONS

Ready-to-microwave par-cooked tubers with a refrigerated shelf life of 21 days were developed without using any chemical preservatives. The rheology of the tuber tissue was studied using a dynamic rheometer for the first time. The technique allows the continuous monitoring of the changes occurring in the potato tissue during the heating and cooling cycles. Significant correlations between the textural characteristics of raw and cooked tubers and the dynamic rheological characteristics of fresh tubers were observed. The technique may be helpful in predicting the viscoelastic characteristics of raw potatoes and the changes in the texture of cooked tubers during refrigerated storage.     

PHYTIC ACID HYDROLYSIS AND BEAN SUSCEPTIBILITY TO STORAGE INDUCED HARDENING1

Two bean cultivars were stored over a 33-day period (75% RH and 41°C). After this period, cooked hardness, levels of phytate, phytase activity and integrity of protein bodies were monitored. The Michigan cultivar, which was the most susceptible to hardening, showed higher initial content of phytate which decreased by 20.7% after 30 days of storage. In contrast, Ojo de cabra, the cultivar less susceptible to hardening, presented lower initial content of phytate and a marked drop of 66.1% in its level during the same period of time. The phytase activity and the autolytic protein body destruction were higher in the last one than those in the former one. These results suggest that the contents of phytate or its rate of hydrolysis are not the major contributor to the seed susceptibility to storage induced hardening of different bean varieties.     

Influences of weather,cultivar and fertiliser rate on grain protein polymer accumulation in field‐grown winter wheat,and relations to grain water content and falling number

BACKGROUND: The reasons for variations in the amount and size distribution of polymeric protein in mature wheat, related to bread‐making quality, are not fully understood and can be sought during the protein polymer formation period of grain maturation. The present study was aimed at investigating the accumulation and polymerisation of grain storage proteins during grain maturation and their relations to changes in falling number and grain water content in four cultivars of field‐grown winter wheat. RESULTS: Proteins were accumulated and polymerised similarly during grain development independently of cultivation environment, cultivar and fertiliser rate. A 3–6 day delay in maturity among cultivars led to a 3–12 day delay in protein accumulation during early grain development. An increase in nitrogen fertiliser rate from 160 to 200 kg N ha^?1 resulted in a 20% increase in the amount of sodium dodecyl sulfate (SDS)‐unextractable protein. Precipitation just before grain harvesting led to 40–50% increases in grain water content and 8–34% decreases in the amount of SDS‐unextractable monomeric protein. At increased grain water contents the fertiliser rate was negatively related to the amount of grain SDS‐unextractable protein. CONCLUSION: Accumulation and polymerisation of grain storage proteins are predetermined events in wheat. Grain moisture content is negatively related to grain storage protein polymerisation, although the rate of decrease is influenced by the fertiliser regime. Copyright © 2008 Society of Chemical Industry     

Influence of Storage Duration and Temperature on Sweet Potato Sugar Content and Chip Color

Sugar concentration and chip color of three orange-flesh and two white-flesh sweet potato cultivars were determined after various lengths of storage at different temperatures. Lightest colored chips were produced from roots chipped immediately after harvest and from cultivars which contained the lowest levels of glucose and fructose. Storage of roots at 32°, 15.6°, or 7°C after harvest resulted in increased sucrose, glucose and fructose concentrations and darker colored chips. Manipulation of storage temperature was not successful in lowering reducing sugar concentration in any cultivar.     

Water uptake and its impact on the texture of lentils (Lens culinaris)

Water uptake behavior of three cultivars of lentils (Boomer, French-green and Nugget) was studied at three different hydration temperature regimes (room temperature, 50 °C and 85 °C). Boomer had the highest amount of water uptake capacity (74.60 g water/100 g of seeds) at room temperature (20 °C) which can be linked with its pore properties. French-green lentils imbibed the largest amount of water at elevated soaking temperatures (50 °C and 85 °C) and can be attributed to its higher seed surface area to volume ratio, high protein content and relatively thinner seed coat. Water uptake at elevated temperatures (50 °C and 85 °C) were predicted by a two parameter Mitscherlich model (R² > 0.99, χ² < 0.5) within 1.36–3.07% average absolute error. At room temperature, only the water uptake of Boomer was reasonably predicted by this model. The texture (hardness) of the soaked lentils was found to be related the amount of water uptake and soaking temperature used rather than seed size or seed mass alone. The hardness values of Boomer, French-green and Nugget at 85 °C after 75 min soaking were reduced to 5.66%, 3.53% and 6.77%, respectively compared to their respective initial seed hardness values. The water uptake capacity of the aged Boomer was found to be significantly reduced compared to the fresh seeds (p < 0.01) while French-green and Nugget do not exhibit significant change (p < 0.05). During 72 h of germination, hardness of all lentil cultivars showed a typical pattern which decreased in the first 24 h followed by an increase compared to the hydrated seeds. A peak hardness value was obtained within 36–48 h before finally declining in all types of lentils. Structural changes within the cotyledon, such as depletion of starch granules, new nuclei formation and development of tissues in vascular bundles and rupture of the seed coat were observed during germination.     

INFLUENCE OF GROWING ENVIRONMENT AND STORAGE DURATION ON QUALITY OF FRESH-PACK CUCUMBER PICKLES3

Fruit of several pickling cucumbers (Cucumis sativus L.) grown in 1978 and 1979 in several environments under two soil nitrogen levels (high vs. normal) were stored for various time periods before fresh-pack processing. Firmness, color and general appearance as examined after equilibration were all highly affected by cultivar, growing environment, and storage duration but somewhat less by nitrogen level. Unexpectedly, color and appearance improved during the first 24 h after harvest. Acceptable firmness was maintained for at least 72 h after harvest. Fruit of genetically firm cultivars generally showed less change in firmness than did fruit of less firm cultivars.     

Chemical analysis and physico-chemical properties of chickpea and lentil cultivars

Some high yielding cultivars of chickpea (Kabuli and desi) (Cicer arietinum) and lentil (Lens esculenta) were used for chemical analysis and physico-chemical properties namely protein, fat, sugars, starch, in vitro digestibility of starch and protein; seed weight, seed volume, seed density, hydration capacity, swelling capacity, water absorption capacity and cooking time. Among chickpea, Gora Hisari (Kabuli) and Haryana Chana (desi) cultivars, and among lentil LH 82-6 cultivar manifested higher contents of protein, fat, sugars, starch and in vitro digestibility of starch and protein. Values of seed volume, seed density, hydration capacity, swelling capacity and water absorption capacity were also found higher for these cultivars which might have contributed towards less cooking time.     

Factors Influencing Serum Separation of Tomato Ketchup

The effect of tomato cultivar, breaking procedure, starting tomato paste concentration, reconstituted paste, homogenization treatment, percent total and water insoluble solids, and pH on serum separation of tomato ketchup was investigated. Homogenization, as well as increasing the total and/or the water insoluble solids of the ketchup reduced separation. Increasing the total solids of the starting tomato paste decreased the rate of separation, but increased the final amount of serum loss from the resulting ketchup. Among tomato cultivars and breaking procedures included in this study, the Peto 98 cultivar (high water insoluble solids content) and the medium break procedure (at 107.2°C after a 10 min hold at room temperature) gave ketchups with the least serum separation.     

Effects of harvest time and storage on dietary fibre components in various cultivars of white cabbage (Brassica oleracea var capitata)

The effect of harvest time and storage on dietary fibre content and composition was investigated in six cultivars of white cabbage (Brassica oleracea var capitata). Three cultivars were of early maturity type (SW Nordpol, Rolly and Balbro) and three of late maturity type (Predikant, Hanna and Lion). The average total dietary fibre (TDF) content was 241 g kg^?1 dry matter (DM) (CV = 13), of which approximately 25% was soluble (CV = 15). The main dietary fibre components were glucose (37%), uronic acid (32%), arabinose (12%) and galactose (8%) residues. Early cultivars generally had a lower TDF content than late maturity types, due to a lower amount of both insoluble (arabinose, galactose and glucose) and soluble (arabinose) polymers. An early cultivar, Rolly, had the highest solubility, 33%, versus 25 ± 4% for the other cultivars. The early cultivar SW Nordpol had a similar TDF content and proportion of soluble dietary fibre (SDF) to the late cultivar Hanna, but the dietary fibre composition was different, with the early cultivar having a lower proportion of arabinose residues. Storage for 6 weeks had minor effects on the dietary fibre. After further storage of the late maturity cultivars, there was an increase in insoluble dietary fibre (IDF) (glucose and uronic acid residues) and a decrease in SDF (arabinose and galactose residues). As a consequence the solubility of TDF decreased from 29 to 19% on average. Harvesting before physiological maturity was reached resulted in a somewhat lower content of TDF and IDF for two cultivars (Predikant and Hanna), while SDF was more or less unaffected for all cultivars. Long‐term storage had fewer effects on cabbage harvested prior to maturity than when harvested at the right physiological maturity. It is concluded that the observed differences between cultivars and after long term storage are of such magnitude that they may affect nutritional properties of the dietary fibre. © 2002 Society of Chemical Industry     

THE EFFECTS OF DIFFERENT STEEPING REGIMES ON WATER UPTAKE,GERMINATION RATE,MILLING ENERGY AND HOT WATER EXTRACT

Five spring cultivars and one winter barley cultivar have been assessed for aspects of malting quality following four different steeping regimes. There were significant effects of cultivar and steeping regime for all characters and cultivar X steeping regime interaction for germination rate and hot water extract. Moisture content after steep was the best guide to the optimum steeping regime. Malting quality was best predicted, in genotypes which germinated rapidly, by determining grain hardness following steeping and 24 hrs germination.     

Milling and physicochemical properties of chickpea (Cicer arietinum L.) varieties

BACKGROUND: Physical characteristics of chickpea (Cicer arietinum L.) seeds such as grain size, weight and hull content are important from a milling and marketing point of view. Chemical characteristics provide the information on nutritional status of grains. Chickpea of Desi (cv. A1) and Kabuli (cv. L550) cultivars were analyzed for their physicochemical, milling and milled flour quality characteristics. RESULTS: Between dry and wet milling, higher yield of dhal was obtained from wet milling, which was found to be true in both cultivars. An extra yield of 2–4% was obtained in wet milling. Between the cultivars, Desi was found to be the higher dhal‐yielding cultivar in both dry and wet milling methods. Fat, ash and protein contents were found to be higher in Kabuli than in Desi and the values were respectively 5.3%, 3.5% and 24.9% for Kabuli and 4.3%, 2.2% and 22.6% for Desi. CONCLUSION: The chickpea cultivars Desi and Kabuli vary significantly in their physical properties such as seed color, size, 100‐seed weight and 100‐seed volume. Between the dry and wet milling, a higher yield (2–4%) of dhal was obtained from wet milling. Between the cultivars, electronic nose analysis of chickpea flour indicated the possibility of differentiating the variations associated with varietal difference and milling. The gel electrophoresis pattern of chickpea showed as many as 15 protein bands in flours from both the cultivars, either in phosphate or SDS buffer. The Rapid Visco Analyzer profile did not show a significant difference between the two cultivars. Copyright © 2008 Society of Chemical Industry     

Effect of temperature and water availability during late maturation of the soybean seed on germ and cotyledon isoflavone content and composition

BACKGROUND: Isoflavone content in soybean seeds is strongly influenced by both environment and genotype. However, little is known about the effect of environment and genotype on isoflavones in germ versus cotyledons. To determine the effect of temperature and soil moisture status during soybean seed development on seed isoflavone concentration and composition, a set of two French and three US cultivars of similar maturity were grown in the greenhouse. At the R6 growth stage, plants were subjected to one of three night/day temperature regimes (13/23°, 18/28° or 23/33 °C) in either optimal or sub‐optimal soil water conditions. RESULTS: In cotyledons, a three‐ to six‐fold variation in total isoflavone content was observed between the high and low temperature treatments, whereas the germ contents had less than a two‐fold variation. Soil water supply had less effect than temperature on the isoflavone contents and compositions. In both seed parts, the isoflavone concentrations were highly dependent on the cultivar. CONCLUSION: These results show that isoflavone content and composition in cotyledon and germ are unrelated and it should be possible to independently manipulate these seed traits through plant breeding and crop management systems. Copyright © 2007 Society of Chemical Industry     

Isoflavone content of soybean cultivars grown in eastern Canada

Soybean (Glycine max (L) Merr) seeds contain isoflavones that have positive impacts on human health. The objective of this study was to determine isoflavone concentrations of early maturing soybean cultivars grown in different environments and to determine their relation to other important seed characteristics. Twenty soybean cultivars were grown in replicated trials at two sites in Montreal, Canada in 2002/2003 and their total and individual isoflavone concentrations were determined by high‐performance liquid chromatography. Seed yield, 100‐seed weight and oil, crude protein and crude fiber concentrations were concurrently determined. Total and individual isoflavone concentrations were significantly affected by cultivar, site and year. Total isoflavone concentration ranged from 360 to 2241 µg g^?1 and averaged 851 µg g^?1 across environments and cultivars. Variation across environments ranged from 20 to 100% for specific cultivars. Total isoflavone concentration was, on average, 40% greater in 2003 than 2002, which was characterized by above average temperatures and severe drought. Despite significant cultivar × year × site interactions, cultivars with consistently high and low isoflavone concentrations across environments were identified. Weak but significant positive correlations were observed between total isoflavone concentration and seed yield, 100‐seed weight and crude fiber, indicating that isoflavone concentration is positively associated with other desirable seed characteristics. Copyright © 2004 Society of Chemical Industry     

Biochemical and textural changes in trifoliate yam Dioscorea dumetorum tubers after harvest

Biochemical and textural changes were investigated in trifoliate yam Dioscorea dumetorum tubers, after harvest, in an attempt to study the chemical and physical changes associated with the raw and cooked tubers and how these relate to the hardening phenomenon of the tubers after harvest. A 2×2×3×4 factorial experiment, with cultivar, storage condition, treatment and storage time as their respective variables, was done. Samples were analysed for moisture, starch, reducing sugars, alcohol-soluble sugars, acid and neutral detergent fibre, cellulose, hemicellulose and lignin. The Warner–Bratzler test cell was used in a TA.XT2 Texture Analyser to measure the hardness of cooked tubers. The moisture and starch contents of the tubers decreased from 77.8 to 70.4% and 70.5 to 66.5 g/100g, respectively in a period of 72 h of storage, suggesting rapid dehydration after harvest and breakdown of starch. All the other chemical indices increased with storage time. These changes were influenced by the storage temperature and the treatment given to the tubers prior to storage. In general, samples stored at 4 °C showed smaller changes in the chemical indices than those at 28 °C, suggesting a temperature-dependence of the changes. Both cultivars of yam showed increase in hardness with storage time. A high correlation (r=0.9503–0.9913) was noted between the texture and the chemical indices of the white cultivars. Storage of the trifoliate yam, Dioscorea dumetorum, immediately after harvest, leads to reduction in moisture and starch contents and increase in sugars and structural polysaccharides. Low temperature storage may reduce the hardening phenomenon. A mechanism for the hardening phenomenon has been proposed.     

Cadmium and zinc concentrations and ratios in seed and tissue of solin (cv LinolaTM 947) and flax (cvs McGregor and Vimy) as affected by nitrogen and phosphorus fertiliser and Provide (Penicillium bilaji)

Field studies were conducted at three locations over 3 years to evaluate the impact of N and P fertilisation, Provide (Penicillium bilaji) and environment on cadmium and zinc concentrations and ratios in the seed and tissue of solin (cv Linola^TM 947) and traditional oilseed flax (cvs McGregor and Vimy). Although differences in Cd and Zn concentrations and ratios in seed and tissue occurred among flax cultivars, there were no differences between Linola^TM 947 and the traditional oilseed flax cultivars. Location had a large effect on Cd concentration in flax seed, presumably owing to differences in soil characteristics. Year‐to‐year variations were also large, with higher seed Cd concentrations occurring in years with greater precipitation. Effects of N, P and Provide on Cd concentration in flax seed and tissue were minor. The effect of environment, cultivar and fertiliser management differed for Zn and Cd, indicating differences in the controlling factors for accumulation of Cd and Zn in flax. © 2000 Society of Chemical Industry     

Differentiation of raspberry varieties according to anthocyanin composition

 Four Spanish raspberry (Rubus idaeus L.) cultivars, Autumn Bliss, Heritage, Rubi, and Ceva, were studied in order to determine, qualitatively and quantitatively, both anthocyanins and vitamin C composition, owing to their significance as dietary compounds with antioxidant activity and also to the relation with color quality. Raspberry anthocyanin composition, determined by HPLC and GC-MS, was characteristic to each cultivar. The higher anthocyanin content expressed as cyanidin-3-glucoside was found in the late cultivars, Rubi (96.08 mg/100 g f.w.) and Ceva (122.88 mg/100 g f.w.). Three cultivars showed cyanidin-3-sophoroside (63.86–21.91 mg/100 g f.w.) and cyanidin-3-glucoside (25.12–14.00 mg/100 g f.w.) as the major pigments, while Autumn Bliss had a similar relative amount of cyanidin derivatives, cyanidin-3-rutinoside being the pigment in major concentration (10.53 mg/100 g f.w.). The vitamin C contents were determined by HPLC. The Rubi cultivar showed the highest amount of vitamin C (31.14 mg/100 g f.w.). The organic acids were determined by HPLC as fruit constituents related to color quality. Citric acid was the main non-volatile organic acid (90%) in all raspberry cultivars and the Rubi cultivar showed the highest total non-volatile organic acids content (2003 mg/100 g f.w.). Hunter color CIE values were also determined, showing that Rubi was the reddest raspberry cultivar. Received: 28 May 1998     

RHEOLOGICAL AND PHYSICAL PROPERTIES OF LOW FAT CAKES PRODUCED BY ADDITION OF CEREAL β-GLUCAN CONCENTRATES

This study investigated the effect of replacing shortenings at 20, 30 and 40% levels with two β-glucan concentrates (BGC) prepared from barley and oat on rheological and physical properties of cake batter, and the quality of the resultant cakes as determined by the volume index, texture profile, color of crust, and crumb and staling at three conditions of storage. The consistency, flow behavior indices, storage and loss moduli of batter, increased as the level of BGCs increased. Addition of BGC decreased the volume and increased hardness. The crust color of cake became lighter and crumb color became darker. Staling, as measured by the development of hardness, increased as a function of storage time and the source and the level of BGC at three storage temperatures. Minimum staling was noticed under frozen storage. Cake containing 20% barley BGC was of similar quality as a cake containing full fat.

PRACTICAL APPLICATIONS

The study is of relevance to the baking industry, which is endeavoring to develop products that contain low fat and offer superior nutritional quality. β-Glucan, a known dietary fiber, offers several health benefits and can be used for replacing fat due to its high water-binding and viscosity-enhancing properties. Cereal-based products are ideal for delivering dietary fiber. This study provides information on how fat substitution by β-glucan concentrates affects the properties of cake batter and the cake quality. Data reported on the consistency and viscoelastic properties of batter are important in the development of new products.