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Strawberry (cv. Senga Sengana) and raspberry (cv. Veten) were processed into jams at 60, 85 or 93 °C and stored at 4 or 23 °C for 8 and 16 weeks. High processing temperature reduced ascorbic acid, total monomeric anthocyanins (TMA) and total phenolics (TP) in strawberries (p 90%), TMA (> 42%) and TP (> 69%). Storage temperature affected stability of anthocyanins, but had minor effect on ascorbic acid, which declined rapidly independent of storage temperature. Storage temperature also explained most of the variance (> 40%) in Chroma of the jams and L* of raspberry jams (53%). Bioactive compounds and color were more stable in raspberry jams than in strawberry jams.

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, r...

BACKGROUND: Retention of nutrients in vegetables during blanching/freezing, cooking and warm-holding is crucial in the preparation of both standard and therapeutic diets. In the present study, conventional cooking in water, and cooking by pouch technology (boil-in-bag, sousvide) were compared in their ability to retain vitamin C, total phenolics and antioxidative activity (DPPH and FRAP) in industrially blanched/frozen tip-cut green beans and swede rods. RESULTS: After conventional cooking, 50.4% total ascorbic acid, 76.7% total phenolics, 55.7% DPPH and 59.0% FRAP were recovered in the drained beans. After boil-in-bag cooking, significantly (P < 0.05) higher recoveries were obtained, i.e. 80.5% total ascorbic acid, 89.2% total phenolics, 94.8% DPPH and 92.9% FRAP. Recoveries aftersousvide cooking were comparable to those of boil-in-bag cooking. By conventional cooking, 13.5 – 42.8% of the nutrients leaked into the cooking water; bysousvide about 10% leaked to the exuded liquid, while no leakage occurred by boil-in-bag cooking. Warm-holding beans after cooking reduced recoveries in all components. Recoveries in swede rods were comparable but overall slightly lower. CONCLUSION: Industrially blanched/frozen vegetables should preferably be cooked by pouch technology, rather than conventional cooking in water. Including cooking water or exuded liquid into the final dish will increase the level of nutrients in a meal. Warm-holding of vegetables after cooking should be avoided. c � 2010 Society of Chemical Industry

Herb decoctions—the aqueous extract of rosemary, sage and thyme, left as by-product after steam distillation of essential oils, were investigated as a source of antioxidants in marinades for turkey thigh meat. Lipid oxidation after marinating, cooking and chill storage (warmed over flavour, WOF) was assessed by thiobarbituric acid-reactive substances (TBARS), GC-MS and sensory judgement on marinated and untreated meat. Results showed that marinating with herb decoctions, which exerted antioxidant activity (free radical scavenging), was an effective means of retarding lipid oxidation in raw and cooked meat. Meat from the rosemary marinade had the lowest TBARS values and volatile levels, while the control samples showed the highest values throughout the marinating, cooking and storage period. Oxidative changes in meat marinated with thyme and sage were significantly more advanced than in meat marinated with rosemary decoction. The partial least squares regression (PLS-R) showed that control samples were strongly related to the oxidation variables (volatiles, TBARS, rancidity) while the marinated meat had high scores for spicy and acidic odour and flavour. Results indicated that antioxidants contained in herb decoction, could be exploited in marinades to prevent rancidity in stored, heat-treated turkey meat products.

The experiment was conducted to study the effects of fermentation of barley, using two different strains of lactic acid bacteria, a Lactobacillus plantarum/pentosus strain isolated from spontaneously fermented rye sourdough (AD2) and a starch-degrading Lactobacillus plantarum (AM4), on contents of mixed-linked (1 --> 3) (1 --> 4)-beta-glucans, alpha-amylase inhibitor activity, inositol phosphates, and apparent digestibility of macronutrients in mink. Effects of fermentation were compared with effects of gamma irradiation (gamma-irradiation: 60Co gamma-rays at 25 kGy). The diets were fed to mink with and without a supplementary enzyme preparation. Both lactic acid fermentation and gamma-irradiation followed by soaking and incubation, reduced concentrations of soluble beta-glucans, phytate and alpha-amylase inhibitor activity. Dietary enzyme supplementation increased significantly digestibility of crude protein, fat, starch and crude carbohydrate (CHO). Fermentation of the barley increased digestibility of starch and CHO. Fermentation with lactic acid bacteria AD2 resulted in higher starch and CHO digestibility than strain AM4, and had greater effect than gamma-irradiation, soaking and incubation. The highest digestibility of starch and CHO was obtained after AD2 fermentation followed by enzyme supplementation. It is concluded that both lactic acid fermentation of barley and enzyme supplementation have positive nutritional implications in the mink by limiting the effects of antinutrients and improving digestibility and energy utilization.

Free anthocyanin and Hunter a'value deterioration in blackcurrant syrups during storage followed fist order reaction kinetics. Half-life of Hunter a'values were 3-4 times higher than half-life values of free anthocyanins. Syrups from various cultivars. differed in color stability. Degassing of syrups prior to storage did not enhance color stability. Day-light storage of syrups lowered half-life of Hunter a'values by 10-30% compared with dark storage. Storage in oxygen permeable packaging materials reduced Hunter a'half-life values up to 90%. Hue values should be used rather than absorbance ratios A502A420 to judge color quality. Hunter a'values should be above 50 and hue values below 40–45' to ascertain acceptable color.

Blanched and nonblanched potato rods (var. Beate) were fermented with Lactobacillus plantarum strain NC8 (109 colony-forming units [CFU]/mL) at 37 °C for 45 and 120 min. Potato rods were pre-fried at 170 °C for 3 min, cooled, and subsequently deep-fried for 2 min 15 s. Potato juice (var. Beate) was fermented with the same strain (108 CFU/mL) at 30 °C for 1 to 5 h. Lactic acid fermentation of nonblanched potato rods for 45 min reduced acrylamide level in French fries with 48%, and with 71% after 120 min. By blanching potato rods before fermentation, reductions in acrylamide after 45 min and 120 min were 79% and 94%, respectively. Blanching, and especially fermentation, reduced visually judged browning of the French fries. Fermentation of potato juice reduced pH from 5.70 to 4.05 after 3 h. Simultaneously, glucose declined from 610.8 mg/100 mL to 7.9 mg/100 mL, fructose from 457.8 mg/100 mL to 0.0 mg/100 mL, and sucrose from 132.0 mg/100 mL to 29.2 mg/100 mL. Asparagine content remained largely unaffected between 0 h (1217.5 μmol/100 mL) and 4 h (1175.6 μmol/100 mL) and increased slightly (1470.3 μmol/100 mL) after 5 h fermentation. Levels of several other amino acids involved in Maillard reactions, that is, alanine, arginine, phenylalanine, and serine, decreased during fermentation. It is concluded that acrylamide formation during production of French fries can be effectively lowered by lactic acid fermentation of potato rods before deep-frying. The reduction is due to reduced levels of reducing sugars rather than reduction of available asparagine.

Efficiency of four concentrations of grape seed extract (0.0, 0.4, 0.8, and 1.6 g/kg) in retarding oxidative rancidity was tested with cooked turkey breast meat. Development in lipid oxidation during 13 days of refrigerated storage was evaluated by means of thiobarbituric acid-reactive substances (TBARS) and volatile compound formation. Hexanal, pentanal, octanal, 2-octenal, 1-octen-3-ol, 2-octen-1-ol, and 1-penten-3-ol showed high correlations (r>0.95) with TBARS values and could, therefore, serve as markers for the oxidation process in the cooked turkey breast meat. Supplementation of grape seed extract prior to cooking significantly improved oxidative stability of minced turkey meat during heat treatment and storage. The ability of grape seed extract to prevent lipid oxidation was concentration-dependent. Vacuum-packaging considerably improved oxidative stability of meat regardless of the low concentration of grape seed extract used. It appears that grape seed extract could be very effective in inhibiting lipid oxidation of cooked turkey meat during chill-storage.

High performance liquid chromatography coupled with diode array and coulometric array detectors were used to characterize and quantify phenolic compounds in achenes and flesh of ripe strawberries (cv Totem and Puget Reliance). Total phenolics and total monomeric anthocyanins were measured and antioxidant activities were evaluated by the FRAP and the ORAC assays. Strawberries contained 1% achenes on a fresh weight basis; however, they contributed to about 11% of total phenolics and 14% of antioxidant activities in strawberries. Ellagic acid, ellagic acid glycosides, and ellagitannins were the main contributors to the antioxidant activities of achenes. The major anthocyanin in flesh was pelargonidin-3-glucoside, whereas achenes consisted of nearly equal amounts of cyanidin-3-glucoside and pelargonidin-3-glucoside. Phenolic content and antioxidant activity of strawberry achenes were reduced by industrial processing. However, the levels were still high and strawberry waste byproduct could thus be a possible source of nutraceuticals or natural antioxidants.

Mechanically deboned turkey meat (MDTM) was stored in different packaging materials (film produced with natural antioxidant (alpha-tocopherol) or synthetic antioxidant) at -20 degrees C for 12 mo in a vacuum, modified atmosphere, or air. One-half of the samples were thawed at 4 degrees C for 24 h after 1 mo of storage and then refrozen. Oxidative rancidity was evaluated during storage by measuring the development of 2-thiobarbituric acid reactive substances (TBARS), and hexanal, a volatile oxidation product. Vacuum- and modified atmosphere-packaged samples had lower TBARS values and hexanal content than air-packaged samples with corresponding treatments. Hexanal content and TBARS values increased with storage time, and the highest levels were obtained after 6 mo of storage. The largest increase was obtained with presence of oxygen. Mechanically deboned turkey meat stored in packages where a natural antioxidant (alpha-tocopherol) was used in production of one of the PE layers, had, in almost every instance, the lowest TBARS values and hexanal content when stored in vacuum or modified atmosphere. However, this difference was not statistically significant. Neither TBARS values nor hexanal content showed dependency of the temperature profile (frozen or frozen/thawed/refrozen) during storage.

Effects of commercial rosemary antioxidants on oxidative stability of mechanically deboned turkey meat (MDTM) compared with Trolox C (vitamin E), ascorbic acid (vitamin C) and control without antioxidant were investigated. Antioxidants were added to meat at three levels. Thiobarbituric acid (TBA) assay and dynamic headspace gas chromatography were used to assess the effects of commercial antioxidants on lipid stability of MDTM during 7 months of frozen storage. Increased levels of TBA-reactive substances (TBARS) and volatile carbonyl compounds were noticed in all meat samples during storage, however most distinctly in meat without antioxidants. Retarding effect of antioxidants on the development of oxidation depended on the level and type antioxidants. Trolox C-a water soluble, synthetic derivative of vitamin E possessed the greatest antioxidative activity reflected by the lowest values of TBARS and volatile compounds. Ascorbic acid was less efficient than Trolox C and Biolox HT-W (rosemary), but more potent than most rosemary extracts in suppressing lipid oxidation especially in the long term frozen storage MDTM. The DPPH() method confirmed that antioxidant activity depends on the concentration of active compounds present in the samples available to scavenge the free radicals formed during the storage period. Supplementation of MDTM with antioxidants could be an alternative method to prevent oxidative degradation of the meat during frozen storage when vacuum packaging is not practical.

Effects of dietary inclusion of dried lactic acid fermented wheat or barley whole meal flours (WMF) on chicken performance were studied. WMFs were fermented for 16 h at 30 ◦ Cb y aLactobacillus strain isolated from a Norwegian rye sourdough. Four diets containing 600 g wheat WMF kg −1 (0, 200, 400 and 600 g fermented kg −1 ) and three diets containing 600 g barley WMF kg −1 (0, 400 and 600 g fermented kg −1 ) were used. Each treatment comprised 125 one-day-old sexed chickens (Ross) were fed on experimental diets until slaughtering at 35 days. Average weight, feed intake and feed:gain ratio in the 0–14, 14–35 and 0–35-day periods were recorded. At day 35, six chickens of each sex from each diet were slaughtered for determination of dressing percentage and abdominal fat. Fermentation significantly reduced levels of total and soluble dietary fibre in cereal WMF. In barley WMF, total-glucans decreased from 36.9 to 29.3 g kg −1 dry matter (DM) and soluble -glucans from 17.8 to 12.6 g kg −1 DM after fermentation. The effects of fermentation on dietary fibre and -glucans were reflected in the analysis of the experimental diets. Total starch was not significantly affected by fermentation. Cereal source and level of fermented WMF in the diets significantly affected chicken body weights. At 14 days, average weights were increased from 277 to 333 g for wheat diets, and from 252 to 322 g for barley diets, when untreated WMF was entirely substituted by fermented WMF. Linear regressions showed significant increase in average weight at 14 days with increasing levels of fermented wheat (R 2 = 0.448 ∗∗∗ ) and fermented barley (R 2 = 0.604 ∗∗∗ ). The effects of fermentation on weights at 14 days were similar for wheat and barley, as there was no significant difference between the regression slopes. Feed intake during the 0–14-day period was not significantly affected by the content of fermented cereal in the diet. Increasing level of fermented cereal significantly improved feed:gain ratio during the 0–14-day period for both

The effects of lactic acid fermentation of wheat and barley whole meal flours (WMF) on digestibility parameters in Atlantic salmon were studied. The WMFs were inoculated with a specific Lactobacillus strain and fermented for 16 h at 30 °C prior to mixing with other feed ingredients and processing by extrusion. Fermentation of the WMFs significantly decreased total starch (P

Five raspberry cultivars ‘Glen Ample’, ‘Glen Lyon’, ‘Malling Admiral’, ‘Malling Orion’ and ‘Veten’, were grown in the south-eastern part of Norway. The potential for the fresh market after different storage treatments was evaluated, by measuring respiration rates, physical and chemical properties and decay. Emphasis was laid on postharvest changes of nutritionally valuable components. Principal component analysis showed that cultivars originating from the same source i.e. cultivars developed at the Scottish Crop Research Institute (‘Glen Ample'and ‘Glen Lyon’), and cultivars from East Malling (‘Malling Admiral’ and ‘Malling Orion’) and the Norwegian cultivar ‘Veten’ were grouped according to their physical and chemical characteristics. ‘Glen Ample’ and ‘Glen Lyon’ showed a good potential for the fresh market. Storage in controlled atmospheres (10% O 2 +15% CO 2 , 10% O 2 +31% CO 2 ) suppressed rotting significantly. Berry colour was darker, and pigment levels increased during 7 days storage in normal atmospheres. Raspberry cultivars with a lighter red colour with less blue like ‘Malling Admiral’ and ‘Glen Lyon’ kept a better colour compared with a darker and more bluish cultivar like ‘Veten’. Measurements of the optical density in the berry juice were highly correlated with total anthocyanin content. Total and soluble solids were unchanged after storage, and titratable acids decreased. The cultivars ‘Glen Ample’, ‘Glen Lyon’ and ‘Malling Orion’ had higher levels of l -ascorbic acid, which were unchanged or slightly increased after one-week storage period.

Wheat and barley whole meal flours (WMFs) were subjected to treatment by fermentation, autoclaving, and fermentation followed by autoclaving. The WMFs were analysed for chemical composition, formulated into wet diets (282 g kg −1 ) and fed to adult mink ( Mustela vison ) for determination of total tract digestibility of total starch, total carbohydrate, crude protein and fat. Fermentation of WMF/water mixtures inoculated with a Lactobacillus sp. (strain AD 2 ) was performed at 30°C for 16 h. Autoclaving was carried out for 60 min at 120°C. Fermentation increased colony-forming units (CFUs) to about 10 8 g −1 and lowered pH to 3.7–3.8 in both WMFs. All carbohydrate parameters were affected by type of cereal, and were, except for total starch, affected by treatment. Levels of total dietary fibre and β-glucans decreased by fermentation in both WMFs. The decrease in total β-glucans from 33.5 to 18.4 g kg −1 in barley WMF, was mainly restricted to the soluble fraction. Glucose levels in barley WMF increased simultaneously from 0.6 to 12.3 g kg −1 . The main effects of autoclaving were increased levels of total dietary fibre, maltose, and increased hydration capacity. With fermentation prior to autoclaving, increases in levels of the fibre fractions and maltose were prevented while hydration capacity prevailed as an effect of autoclaving. Compared with fermentation alone, the combined treatment increased damaged starch levels and hydration capacity. Digestibilities of total carbohydrate, crude protein and fat were significantly higher for wheat than for barley. Fermentation had no effect on digestibility of total starch or total carbohydrate of wheat, but increased digestibility of total starch of barley significantly from 0.742 to 0.880, and of total carbohydrate from 0.457 to 0.616. Autoclaving had no significant effect on digestibility of total starch and total carbohydrate of wheat. Digestibility of total starch and total carbohydrate in barley increased significantly after autoclaving. Total starch and total carbohydrate digestibility of both wheat and barley were significantly enhanced by combined fermentation and autoclaving compared with fermentation alone. Compared with autoclaving alone, combined fermentation and autoclaving promoted no significant improvement of total starch and total carbohydrate digestibility in wheat, whereas total carbohydrate digestibility in barley increased from 0.605 to 0.672. Fat digestibility was slightly improved by both fermentation and autoclaving. Autoclaving of cereals reduced significantly the faecal dry matter contents of mink. This effect could be counteracted by preceding fermentation. In conclusion, lactic acid fermentation of wheat and especially barley provided chemical changes of benefit for carbohydrate digestion in the mink.

By modification and combination of existing methods we have developed a rapid method for quantification of 6-methoxymellein in carrot roots by means of boiling water and solid phase extraction, followed by high performance liquid chromatography (HPLC). The performance of the method was found to be acceptable, when tested by three consecutive boiling water extractions from carrot samples with different levels of 6-methoxymellein. The recovery was 96–99% after one extraction. With this method it was possible for one person to extract 20 samples during a working day and further quantify the amount of 6-methoxymellein by automatic HPLC the following night.

Frozen blueberries (Vaccinium corymbosum L.) were processed into juice and concentrate, and the changes in anthocyanin pigments and polyphenolics (cinnamates, procyanidins, flavonol glycosides) were monitored. While juice yield was 83%, only 32% of the anthocyanins were recovered in single-strength juice. Flavonol, procyanidin and chlorogenic acid recoveries in juice were 35%, 43%, and 53%, respectively. The proportion of polyphenolics remaining in the press-cake residue ranged from 1% (chlorogenic acid) to 18% (anthocyanins). Pronounced losses of anthocyanins and polyphenolics during milling and depectinization are believed to be due to native polyphenol oxidase. Losses during concentration ranged from 1.5% (anthocyanins) to 20% (procyanidins). Striking changes occurred in the anthocyanin profile with malvidin glycosides being most stable and delphinidin glycosides the least.

Four carrot varieties; ‘Fontana’, ‘Merida’, ‘Newburg’ and ‘Nandrin’ were grown at six locations in Norway, ranging from 58 ° 20'N to 69 ° 27'N. Sensory quality, chemical composition and growth parameters were clearly influenced by the growing temperature during June, July, August and September. Principal component analysis (PCA) showed three factors explaining 75% of the total variation. PC1 was a temperature related factor grouping the carrot samples according to their growing site in direction north to south. The most prominent variables for PC1 was root weight, root length, root diameters, sensory colour and flavour variables being characteristic for the southern locations, while whiteness and sickly sweet was characteristic for the northernmost samples. PC2 and 3 explained the genetic variation, mainly determined by the variation in sugar related variables and texture. The influence of temperature on various blocks of variables was shown by means of partial least-square (PLS2). The rate of prediction was generally low, but temperature was able to predict 36% of the sensory variables, 21% of the chemical variables and 56% of the physical variables by the first two factors. Temperature predicted 57% of the variation in α- and β-carotene content of the carrots, and 45% of the variation in sensory bitter components.

Carotene contents of four carrot (Daucus carota L.) varieties, grown at six latitudes in Norway, demonstrated that carrots grown at two locations far south had the highest carotene contents, while no effect of variety was seen. Carotene contents of carrot chips correlated significantly with those of raw carrots and averaged 88% of initial amount, about 20% being identified as 9-cis β-carotene. The carotenes corresponded to 4140 retinol equivalents (RE) per 100 g chips, demonstrating carrot chips as a good source of carotenes. For raw carrots, CIE (1976) L∗, a∗ and Hue° values correlated significantly with carotene content, while for chips, a∗, b∗ and Hue° values correlated with carotene content.

Carrot variety had a significant influence on the dry matter, redness ( a ∗ ) and sucrose content, while cultivation site (environmental condition) had a significant influence on the dry matter, lightness ( L ∗ ), redness ( a ∗ ), sucrose and glucose content. The chemical content of raw carrots could be used to predict the quality of carrot chips by means of three factors when partial least-squared analysis was applied. Factor 1 was explained by the difference in colour at the different cultivation sites, factor 2 by the difference in sucrose content in the different varieties, while factor 3 covered both colour and sugars, and grouped the cultivation sites in three where the carrots had similar chemical composition.

Phenolic compounds in fruits of 27 cultivars of strawberry (Fragaria x ananassa Duch.) grown in Norway were characterised and quantified by HPLC-DAD-MS(n). Total phenolic content, calculated as the sum of the individual compounds, varied 2.3-fold among cultivars, i.e., from 57 to 133mg/100g of fw. There were significant differences among cultivars in concentration of all phenolic compounds. The highest variation between cultivars was found for cinnamoyl glucose (0.6-24.9mg/100g of fw). Concentration of anthocyanins, the most abundant class of phenolic compounds in the majority of the cultivars, varied from 8.5 to 65.9mg/100g of fw. Flavan-3-ols (11-45mg/100g of fw) and ellagitannins (7.7-18.2mg/100g of fw) contributed on average 28% and 14% to total phenolic contents in the strawberry cultivars, respectively. In three cultivars harvested at three stages of ripeness, anthocyanins and cinnamic acid conjugates were the compounds most affected by ripening. The anthocyanin profile for the individual cultivars was only slightly affected by ripening and growing conditions.

Carrot chips with a light red-yellow colour were obtained by lactic acid fermentation of carrot slices in a brine prior to deep-frying. The fermentation process decreased the content of reducing sugars up to 75%, thereby restricting the extent of Maillard reactions during heating. Rinsing the slices after fermentation but prior to deep-frying enhanced sugar removal. Three strains of Lactobacillus were tested. Strain NCIMB 40450 reduced sugar levels faster than strains NCDO 1193 and NCDO 1752. The best colour properties were obtained when carrot slices were deep-fried after 24 h fermentation.

The effects of dairy ingredients (1,3,5%)--ordinary and high-viscosity sodium caseinate, skim-milk powder, whey protein or demineralized whey powder--on sensory properties and instrumental texture and color of sausages, were investigated. Sausages were formulated with 2 or 4% potato starch and cooked to a core temperature of 76 or 82 degrees C. Principal component analysis (PCA) revealed three dominating factors for sensory properties; the first related to dairy ingredients and starch concentrations, the two others to type of dairy ingredients. Results were verified by analysis of variance (ANOVA). Results of sensory analysis were further verified by textural and color analysis using PCA and ANOVA, respectively.

Color stabilities were compared using various color indices-free an-thocyanin content, color density, polymeric color, browning and Hunter color values. Comparisons included both strawberry syrup plain and fortified with anthocyanins and/or ascorbic acid levels equivalent to those of blackcurrant syrup. Anthocynin pigments of unfortified strawberry syrup were less stable than those of blackcurrant syrup. Color stability of strawberry syrup fortified with equal anthocyanin concentrations was similar to blackcurrant syrup. Hence, color stability was dependent upon total anthocyanin concentration rather than qualitative pigment composition. Addition of ascorbic acid decreased color stability of strawberry syrup. Strawberry anthocyanin pigment fortification had a protective effect on ascorbic acid.

Color of rainbow trout (Onchorynchus mykiss) was investigated using sensory and instrumental analysis. When judged in pairs with equal carotenoid concentration, astaxanthin caused less whiteness, higher chromaticity and more red hue of trout flesh than canthaxanthin. Sensory assessed whiteness, chromaticity and red hue significantly correlated with instrumental values for lightness, chromaticity and hue [CIE (1976) L*a*b* and H(°)ab]. Multivariate regression analysis improved the predictability for all sensory variables compared with univariate analysis. Prediction of carotenoid concentration from instrumental values was better for astaxanthin than for canthaxanthin.

Three different HPLC columns were tested for their suitability for the analysis of myoglobin and haemoglobin in beef. Complete separation of the two proteins was obtained with an anion exchange column and a column based on hydrophobic interaction. With the latter column a recovery close to 100% was obtained for both proteins when they were added to meat extracts. For both proteins, the standard error of the mean for repeated analyses of ground beef was less than 2% of the detected amount. The method is considered as suited for quantitative routine analysis of myoglobin and haemoglobin in beef and beef products.

To improve accuracy in the determination of anthocyanin purity and succeeding antioxidant capacity, 1H and 13C nuclear magnetic resonance spectroscopy have been combined with high-performance liquid chromatography (HPLC) equipped with a diode array detector and UV-vis spectroscopy in the analysis of anthocyanidin 3-glycosides and 5-carboxypyranoanthocyanidin 3-glycosides. The molar absoptivity (epsilon) values were found to be relatively similar, in contrast to previously reported literature values, and the average epsilon values for both anthocyanidin 3-monoglycosides and 5-carboxypyranoanthocyanidin 3-glycosides were proposed to be 22,000 and 23,000 in acidified aqueous and methanolic solutions, respectively. To assess the influence of structure on the potential antioxidant capacity of anthocyanins, the 3-glucosides of pelargonidin (1), cyanidin (2), peonidin (3), delphinidin (4), petunidin (5), malvidin (6), 5-carboxypyranopelargonidin (8), 5-carboxypyranocyanidin (9), 5-carboxypyranodelphinidin (11), 5-carboxypyranopetunidin (12), and 5-carboxypyranomalvidin (13) and the 3-galactosides of cyanidin (7) and 5-carboxypyranocyanidin (14) were examined by a ferric ion reducing antioxidant power (FRAP) assay. The reducing capacities of the individual anthocyanins were in the range of 0.9-5.2 micromol of Trolox equivalents/micromol. The two 5-carboxypyranoanthocyanins 11 and 9 and the four common anthocyanins 2, 4, 7, and 14, all possessing pyrogallol or catechol type of B rings, showed the highest antioxidant capacity measured by FRAP. However, the inclusion of the 5-hydroxyl in the D ring and just one oxygen substituent on the B ring in 8 diminished the reducing capacity considerably. Correspondingly, electrochemical behavior of 5-carboxypyranoanthocyanidin 3-glucosides and anthocyanidin 3-glucosides was derived using HPLC coupled to a coulometric array detector set from 100 to 800 mV in increments of 100 mV. The relative order of the reducing capacity of the various 5-carboxypyranoanthocyanidin 3-glucosides and anthocyanidin 3-glucosides were nearly alike, whether determined by coulometric array detection or FRAP.

In this study the impact of achenes on polyphenolic compounds, ascorbic acids, and antioxidant activities in strawberry purees at production and after storage at 6 and 22 degrees C for 8 and 16 weeks was investigated. Strawberry purees were made from flesh, berry, and achene-enriched homogenate and contained 0, 1.2, and 2.9% achenes, respectively. At production, strawberry purees made from flesh contained more anthocyanins, p-coumaroyl glycosides, and ascorbic acids, whereas increasing achene levels caused increasing levels of ellagic acid derivatives, proanthocyanidins, flavonols, total phenolics (TP), and antioxidant activities. In addition, the anthocyanins, TP, and ferric reducing ability power (FRAP) in purees with more achenes were better retained during storage. Ascorbic acids and anthocyanins declined rapidly during storage, whereas other polyphenols and antioxidant activities were more stable; that is, the contributions from anthocyanins and ascorbic acids to TP and antioxidant activities decreased. The findings that achenes contributed significantly to polyphenol content and stability of strawberry purees may be interesting in a nutritional and, thus, commercial, perspective.

Phenolic compounds in strawberry (Fragaria x ananassa) fruits were identified and characterized by using the complementary information from different high-performance liquid chromatography detectors: diode array, mass spectrometer in positive and negative mode, and coulometric array. Electrochemical profiles obtained from the coulometric array detector contributed to the structural elucidation suggested from the UV-vis and mass spectra. About 40 phenolic compounds including glycosides of quercetin, kaempferol, cyanidin, pelargonidin, and ellagic acid, together with flavanols, derivatives of p-coumaric acid, and ellagitannins, were described, providing a more complete identification of phenolic compounds in strawberry fruits. Quercetin-3-malonylhexoside and a deoxyhexoside of ellagic acid were reported for the first time. Antioxidative properties of individual components in strawberries were estimated by their electrochemical responses. Ascorbic acid was the single most important contributor to electrochemical response in strawberries (24%), whereas the ellagitannins and the anthocyanins were the groups of polyphenols with the highest contributions, 19 and 13% at 400 mV, respectively.

High-performance liquid chromatography coupled with a coulometric array detector was used to characterize the electrochemical behavior of 17 flavonoids and three cinnamic acid derivatives. The antioxidant activity of these phenolic compounds was evaluated by the ferric reducing activity power (FRAP), the oxygen radical absorbance capacity (ORAC), and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assays. All flavonoids, except kaempferol-3-rutinoside, malvidin-3-glucoside, and peonidin-3-glucoside, had two oxidation potentials (100-300 and 700-800 mV). Quercetin and myricetin had an additional oxidation wave at 400 mV. The electrochemical responses at a relatively low oxidation potential (300 mV) and the cumulative responses at medium oxidation potentials (400 and 500 mV) had the highest correlations with antioxidant activities. The highest correlations between electrochemical characteristics and antioxidant activities were found between electrochemical responses and antioxidant activities obtained in the FRAP assay and in the DPPH assay after short reaction periods. Lower correlations were revealed between electrochemical responses and antioxidant activities obtained in the ORAC assay.

There is a great interest in food components that possess possible health-protecting properties, as is the case with flavonoids. Previous research showed that conventional apple juice processing resulted in juices poor in flavonoids and with a low antioxidant activity. This paper shows that it is possible to improve flavonoid content in juice and its antioxidant activity by applying an alcoholic extraction either on the pulp or on the pomace. The levels of flavonoids and chlorogenic acid in enriched juice were between 1.4 (chlorogenic acid) and 9 (quercetin glycosides) times higher than in conventional apple juice. In enriched juice the antioxidant activity was 5 times higher than in conventional apple juice, with 52% of the antioxidant activity of the originating fruits present. The novel processing method had similar effects for three apple cultivars tested (Elstar, Golden Delicious, and Jonagold). The taste and color of enriched juice were different from those of conventional juice.

Color standards from the Natural Color System (NCS) were selected by a sensory panel to match color of raw flesh of astaxanthin-fed Atlantic salmon (Salmo salar L.). The NCS notations, blackness, chromaticity and hue, of the most frequently selected standards are given. A linear relationship between average NCS hue and NCS chromaticity values of each salmon was obtained, the hue being more reddish at high color intensities. NCS chromaticity and hue were both significantly correlated with carotenoid concentration and with instrumentally obtained CIE (1976) a*, b* and hue values. Procedures for the selection of NCS standards and for the practical use of a color card in the evaluation of salmon color, were developed.

Strawberries were individually quick-frozen (IQF) and packed with 10, 20 and 40% by weight added sucrose. Samples were stored at - 15°C for 3 yr and analyzed for: total monomeric anthocyanin pigment, polymeric color, browning and color density. To test the influence of thawing, half the samples were thawed and refrozen prior to analysis. One- and two-way analysis of variance (ANOVA) revealed that sucrose addition had a significant protective effect on anthocyanin pigment content and also retarded browning and polymeric color formation. Thawing accelerated these color degradative reactions.

The ability of several instrumental methods to predict visual color deterioration in blackcurrant syrup was studied using a linear calibration method. Commercial syrup was used in a storage experiment to generate samples of a wide color quality range. Packaging material greatly influenced color stability, storage time varied from 2 months with high-density polyethylene bottles, to 8 months with polyvinylchloride, 12 months with polyester and more than 18 months with glass bottles. Combinations of Hunter L', a' and b' values and of absorbances at three selected wavelengths, the absorbance ratio A520/A420 hue and Hunter a’all revealed acceptable predicting abilities for visual color. Multivariate treatment of the data gave best predictions. The absorbance ratio A520/A420 has the advantage of being independent of initial pigment content.

Flesh colour of eight canthaxanthin-pigmented farmed and eight astaxanthin-pig-mented with Atlantic salmon (Salmo salar L.) was measured by instrumental analysis. The colour of raw, baked and cold smoked flesh from cultured and wild salmon was compared using reflectance spectra transformed into CIE (1976) L ∗ a ∗ b ∗ values. In this system L ∗ represents lightness of salmon flesh colour, a ∗ redness and b ∗ yellowness. CIE (1976) L ∗ a ∗ b ∗ values obtained with a portable instrument (Minolta Chroma Meter) showed that intensity of redness ( a ∗ ) of raw, baked and smoked salmon increased with increasing carotenoid concentration of the raw flesh, while lightness ( L ∗ ) decreased. Intensity of yellowness ( b ∗ ) was not significantly influenced by carotenoid concentration. Baking and smoking caused a ∗ to decrease, while L ∗ increased. Values obtained by the portable instrument were in good accordance with corresponding values obtained with a HunterLab LabScan II sphere spectrocolorimeter. The reflectance ratio R 650 R 510 of raw, baked and smoked salmon flesh was significantly correlated to carotenoid concentration, but to a lesser extent than CIE (1976) a ∗ values. The present analyses did not reveal colour differences between farmed and wild salmon except for those caused by differences in carotenoid concentration.

The starch-degrading activity of beef muscles, commercial beef and pork cuts and of bovine blood plasma was studied. Beef sirloin and shoulder cuts were shown to contain enzymes capable of degrading starch. The activity corresponded to an increase in reducing equivalent of about 400–600 μequiv per 100 g fat free muscle per minute. In the commercial meat cuts, the starch-degrading activity of pork was higher than that of beef. In bovine blood plasma and potato flour mixtures starch degradation was observed in samples that were heated and subsequently stored. The most extended starch degradation was found in samples heated to 60°C prior to storage. In meat sausages the maximum starch degradation during storage was obtained when samples were heated to 70°C. The increase in reducing equivalents during 7 days' storage at 6°C corresponded to the hydrolysis of about one-third of the starch content of the sausage. Most of the increase in the reducing ability was detectable as glucose, indicating that a major part of the enzymic starch degradation resulted in free glucose. No decrease in the overall number of glucose equivalents was observed in the meat sausages during storage. The implication of starch degradation for the textural quality of sausages is discussed.

The four blackcurrant cultivars Ojebyn, Ben Nevis, Ben Lomond and Silvergieter have been evaluated with reference to their suitability for syrup production. The examination was based on sensory and physico-chemical characterisation, and was performed on the berries themselves and the syrup. The results show that Ojebyn is less suitable for syrup production, while Ben Nevis and Ben Lomond differ insignificantly in most qualities from the reference cultivar, Silvergieter. Criteria for the evaluation of cultivars for industrial suitability are discussed.

Enzymic starch degradation ability of cooked beef sausages was studied, using irradiation to extend storage life of vacuum-packed sausages. With cooking temperatures between 60 and 75°C, starch degradation increased significantly during storage. Variation in beef cuts or freezing of meat prior to processing did not influence the extent of starch degradation. The main product from starch hydrolysis was glucose, while small amounts of oligosaccharides containing two to four glucose units were detectable. An accumulation of glucose corresponding to 10% of the initially added starch did not significantly influence firmness or the amount of liquid exuded from sausages at the end of the storage period.

Twelve strawberry varieties were investigated for potential use by the jam processing industry. Chemical, physical and sensory analyses were performed with fresh and thawed fruits and with jams made from the fruits. Fresh fruits were analysed for dry matter, soluble solids, pH, titratable acids and ascorbic acid. Total anthocyanin and degradation indexes were determined in both fresh fruits and in jams. Firmness of fresh and thawed fruits, as well as the amount of juice lost upon thawing (drip loss) were tested for each variety. Except for colour, no significant correlation (P

Color of wild, astaxanthin pigmented, and farmed, canthaxanthin pigmented, Atlantic salmon (Salmon salar) was evaluated by spectroscopy and visual sensory analyses. A more yellow hue in farmed salmon color compared with wild salmon was found in acetone extracts of raw salmon flesh and by visual sensory analyses of raw, baked and smoked salmon flesh. With instrumental color analysis directly on raw flesh, no significant differences in color between wild and farmed salmon were found. The redness and hue in raw and baked salmon flesh and the redness in smoked salmon were correlated to the pigment concentration in raw salmon. The redness and hue in processed salmon were predictable from the redness and hue of raw flesh.

Six strawberry varieties were evaluated as raw materials for industrial jam production. The investigation involved chemical, physical and sensory analyses of fresh and frozen/thawed fruits as well as jam at the time of production and after 3 months of storage. Among the varieties studied, Jonsok and Senga Sengana appeared most suitable, followed by Bounty and Tenira. The other varieties, Fructana and Totem, were less satisfactory for this purpose. Based on linear correlation analyses (P

The relationships between CIE (1976) L*a*b* color parameters from a Hunter LabScan II Sphere Spectrocolorimeter and two Minolta Chroma Meters were evaluated. Jams, yoghurts with jam, salami-type dry sausages, raw cauliflowers, mashed and raw potatoes and various color standards were used as samples. The numerical values of the color parameters depended upon the instrument used. The relationships between the color parameters could be described by linear regressions which were specific for each type of food except for mashed potatoes and cauliflower. Best predictions of color parameters from one instrument to another were obtained with the most homogenious types of food.

The starch content of meat products is determined as glucose by an enzyme-hydrolytic method using thermo-stable α-amylase and amyloglucosidase for hydrolysis. The method is compared with a polarimetric and an acid-hydrolytic method. The recovery in various cooked and uncooked sausages containing up to 12% starch ranged from 92 to 102% of the starch content estimated from the recipe. The average coefficient of variation was 2%. The presence of lactose did not influence the starch determination. In a collaborative study an average of 103% of the estimated starch value was recovered. The random and systematic errors were of equal size, each amounting to a maximum of 8% of the starch content of the sausages. The application of the method for food inspection purposes is discussed. The method is considered to be suited for starch analysis in meat products.

Free sugar composition of strawberries during thawing and up to 5-hr after-thaw storage was studied. Sucrose content of drained fruits and juice decreased by 70% whereas fructose and glucose content increased during thawing at 4 °C. Total free sugar content remained constant. Sucrose degradation caused by invertase activity in the strawberry fruit rather than by sucrose synthase activity or acid hydrolysis was demonstrated. The sucrose inversion was more pronounced in drained fruits than in juice. Sucrose inversion also occurred when fruit was thawed by a current of air, microwave heating, or 35 °C water, but to a lesser extent. The 5-hr holding period after thawing resulted in comparable sugar composition with all thawing procedures. For best preservation of the free sugar composition a fast thawing method should be chosen.