Instrumental acoustic-mechanical measures of crispness in apples

Texture is a quality attribute closely related to the structural properties of the apple cellular tissue and is claimed to be the most important aspect affecting consumer acceptability apart from taste. Instrumental and human-based assessment of apples crispness are presented in this paper. A commercially available acoustic AED detector, interfaced with a TA.XT.plus Texture Analyzer, was used to collect both the acoustic emissions recorded during the instrumental mechanical penetration test, and the acoustic emissions resulting from the first bite of an apple flash, which were accomplished by 10 subjects with random dental state. Seven commercial cultivars of apples with different textural characteristics (Fuji, Golden Delicious, Granny Smith, Pink Lady, Renetta Canada, Royal Gala, and Stark) were analyzed. In order to measure the apple juice content, the expressible fluid released from the apple flash during compression was also quantified.Merging distinctive parameters taken from the mechanical signals and simultaneously recorded acoustic traces allowed apples to be clustered based on their crispness attributes using principal component analysis (PCA), a qualitative approach for multivariate data set.Results showed that sounds emitted during the human biting could not be assumed as a capable predictor of the sensory attribute of crispness, while apples can be efficiently distinguished for crispness by means of coupled acoustic and mechanical texture analysis. Finally, the inclusion of juiciness in the acoustic-mechanical PCA data set did not significantly increase the efficiency in cluster separation in terms of the texture crispness property.     

Systematic Comparison of Hedonic Ranking and Rating Methods Demonstrates Few Practical Differences

Hedonic ranking is one of the commonly used methods to evaluate consumer preferences. Some authors suggest that it is the best methodology for discriminating among products, while others recommend hedonic rating. These mixed findings suggest the statistical outcome(s) are dependent on the experimental conditions or a user's expectation of “what is” and “what is not” desirable for evaluating consumer preferences. Therefore, sensory and industry professionals may be uncertain or confused regarding the appropriate application of hedonic tests. This paper would like to put this controversy to rest, by evaluating 3 data sets (3 yogurts, 79 consumers; 6 yogurts, 109 consumers; 4 apple cultivars, 70 consumers) collected using the same consumers and by calculating nontied ranks from hedonic scores. Consumer responses were evaluated by comparing bivariate associations between the methods (nontied ranks, tied ranks, hedonic rating scores) using trellis displays, determining the number of consumers with discrepancies in their responses between the methods, and comparing mean values using conventional statistical analyses. Spearman's rank correlations (0.33–0.84) revealed significant differences between the methods for all products, whether or not means separation tests differentiated the products. The work illustrated the inherent biases associated with hedonic ranking and recommended alternate hedonic methodologies.     

Nutraceutical potential of polyphenolic fractions from Annurca apple (M. pumila Miller cv Annurca)

The capacities of polyphenolic extracts from Annurca apple peel and flesh to inhibit the glucose and cholesterol uptake by HepG2 cells were evaluated, and compared with those of other conventional cultivars, such as Red Delicious (RD), Pink Lady (PL), Fuji (F) and Golden Delicious (GD). RD peels exhibited the best hypoglycaemic effects, while Annurca flesh appeared the most active in reducing cell cholesterol uptake among the cultivars tested. The influence of the apple polyphenolic extracts on the cell proliferation and oxidative stress was also evaluated. Particularly, RD, Annurca and PL peels decreased proliferation by a 62.5%, 48.0% and 37.5%, respectively, probably due to their prooxidant capacity. Conversely, flesh extracts appeared more protective of cells than peels: Annurca and RD, particularly, proved to be able of increasing proliferation by a 32.2% and 11.1%, respectively, probably due to their capacity of reducing cell physiological radical levels of a 33.3% and 19.9%, respectively.     

Quality Measurement of Intact and Fresh-cut Slices of Fuji, Granny Smith, Pink Lady, and GoldRush Apples

ABSTRACT: Development of fresh-cut apple products requires consideration of cultivars that store well as both intact and fresh-cut fruit. We compared the instrumental and sensory quality of 2 apple cultivars, Granny Smith and Fuji, that are used for fresh cutting with 2 new cultivars, Pink Lady and GoldRush, which were considered to have quality characteristics suitable for fresh cutting. Firmness, titratable acidity (TA), soluble solids content (SSC), and aromatic volatile concentration were measured in intact fruit of the 4 cultivars during 12 mo storage in air at 0 °C and during 3 wk storage at 5 °C as fresh-cut slices. After 1 wk storage as fresh-cut slices, sensory evaluations for acceptability of flesh and peel appearance, flavor, texture, and overall eating quality were performed. During storage, GoldRush apples maintained > 80 N firmness, approximately 17% SSC, > 0.5% TA, and had high aromatic volatile production, that is, maintained quality better than the other cultivars. The quality and shelf stability of GoldRush slices were also as good as or better than slices from the other cultivars, whereas Granny Smith slices generally rated lower than the other cultivars. The acceptability of flavor, texture, and overall eating quality of GoldRush slices was as good as that for Pink Lady and Fuji. The quality of GoldRush apples can be maintained throughout the year in refrigerated air storage and still remain suitable for fresh-cut processing. The results indicate that GoldRush and Pink Lady are 2 promising new, high-quality apple cultivars for fresh cutting. Keywords: fresh-cut fruit, Malus × domestica , postharvest quality, respiration rate, shelf life     

Sensory Characteristics of Apple Juice Evaluated by Consumer and Trained Panels

ABSTRACT: To identify sensory characteristics of unclarified apple juice and to compare unclarified and clarified types, 140 consumers and 10 trained panelists evaluated 16 commercial apple juice samples (4 clarified and 12 unclarified). Unclarified and clarified juices were clearly separated by the first principal component (PC1), whose main factor was fresh, green, and sweet aroma. It was difficult to predict consumer preference by regression models using trained panel preference and analytical attributes. Mapping consumers' overall preferences on a sensory profile made by PC1 and PC2, the consumer panel preferred apple juice with moderately increased fresh and green aroma and thoroughly decreased sour and astringent.     

苹果混合汁配比的研究

以黄元帅、红秦和红富士3种苹果为试材,运用D-最优混合设计（Mixture-D-Optimal design）,以糖酸比为响应值,对3种苹果原汁进行不同配比的复合调配,并应用模糊数学对复合苹果汁进行了感官评定。根据复合苹果汁的风味．确定了苹果复合汁最优配方为：黄元帅原汁50％、红秦原汁50％,成品的糖酸比为30．77。     

The order of tasting and information presentation in an experimental auction matters

Experimental auctions are used to determine the price consumers are willing to pay for products with specific attributes, including sensory attributes. Previous experimental auctions have demonstrated that taste is an important factor in determining panelist bid price. Those auctions generally conducted the tasting after providing the explicit product information. Our objective was to determine the relative difference in panelist bidding prices between tasting apple samples before verses after observing displays containing explicit information about the apples. We chose four apple varieties for this study: Honeycrisp, Braeburn, Pink Lady and Red Delicious. Each variety of apple had been grown under two conditions: conventional and organic. A total of 86 panelists participated in one of two information scenarios. Panelists in the first scenario first tasted the apples and placed individual bids for one pound of each of the apple samples. They then viewed information displays (apple name and growing condition) of the apples and placed a second bid. The process was reversed for the panelists in the second scenario in that the information was given before the tasting. When the sensory properties of products were presented before other product information, the impact of the explicit product information was minimized. When product information was presented before the sensory evaluation, it biased the bid prices. To better understand the influence of both the implicit sensory properties and the explicit product information, presentation orders of both types of information should be balanced in an experimental auction.     

Potential Prophylactic Properties of Apple and Characterization of Potent Bioactive from cv. “Granny Smith” Displaying Strong Antimutagenicity in Models Including Human Lymphoblast TK6+/− Cell Line

Potential prophylactic attributes in terms of antimutagenicity, antioxidant, and radioprotective properties were evaluated for 8 common apple cultivars namely “Fuji,” “Golden Delicious,” “Granny Smith,” “Ambri Kashmiri,” “Kinnaur,” “Red Delicious,” “Royal Gala,” and “Shimla,” where cultivar based significant variation was observed. Cv. “Granny Smith” displayed significantly higher and broad spectrum antimutagenicity in Escherichia coli rpoB based rifampicin resistance (Rif^R) assay, whereas, “Ambri Kashmiri,” “Royal Gala,” and “Shimla” showed lower antimutagenicity. Cultivars “Ambri Kashmiri,” “Kinnaur,” and “Red Delicious” exhibited strong antioxidant activity than cv. “Granny Smith” as assayed by radical scavenging, reducing potential and radioprotective property assays. The antioxidant and radioprotective properties were found to be better correlated than antimutagenicity. Suppression of error‐prone DNA repair pathway (such as E. coli SOS response) was found to be one of the possible mechanisms contributing to its antimutagenicity. Phenolic extract of “Granny Smithˮ showing higher antimutagenicity was HPLC purified and the bioactive fraction (t_R 35.4 min) contributing maximally (∼80%) to the observed antimutagenicity was identified as procyanidin dimer (PD) by ESI‐MS/MS. The above observed antimutagenicity in bacterial assay system was well reproduced in Thymidine Kinase Mutation (TKM) assay performed using human lymphoblast cell line (TK6^+/−) cell line making the findings more prophylactically relevant.     

Bioactive phytochemicals in apple cultivars from the Portuguese protected geographical indication “Maçã de Alcobaça:” Basis for market segmentation

Phytochemical composition and antioxidant activity of eight apple (Malus domestica) cultivars (“Casa Nova,” “Fuji,” “Golden Delicious,” “Granny Smith,” “Jonagored,” “Reinette Grise,” “Royal Gala,” and “Starking”) from the “Maçã de Alcobaça” protected geographic indication, Portugal, were characterized to support market segmentation based on phytochemical content. Total phenolics, flavonoids, and anthocyanin contents, individual polyphenols and antioxidant activity were assessed in the flesh and skin of fruit at the ripe stage. A market segmentation of apple cultivars based on these bioactive phytochemicals is proposed. Fruit eaten with the peel can be segmented in three classes: (1) the flavonoid-rich “Starking,” “Reineta,” “Galaxy,” “Casa Nova,” Jonagored;” (2) the quercetin-rich “Fuji,” “Galaxy,” “Casa Nova;” and (3) flavonol and procyanidin-rich “Starking,” “Reinette,” “Jonagored,” “Casa Nova.” When apples were peeled before consumption, two phytochemical classes were proposed: (1) the flavonoid-rich “Reinette” and “Casa Nova,” and the (2) chlorogenic acid-rich “Reineta,” “Casa Nova,” and “Starking.”     

Effect of Dipping Pre-treatment with Unripe Grape Juice on Dried “Golden Delicious” Apple Slices

The consumption of apple chips is increasing in the last decades because of the consumer’s preferences towards healthy snacks. However, the enzymatic browning, which is attributed mainly to polyphenol oxidase (PPO, EC 1.10.3.1) activity, negatively affects the sensory, nutritional, and antioxidant properties of dried apples as a consequence of the oxidation of phenolic substrates during post-harvest stages. The antibrowning and antioxidant effects of dipping pre-treatments with unripe grape juice as well as reference formulations including a mixture of 1% w/v ascorbic acid and 1% w/v citric acid, 6% w/v NatureSeal®, and 0.1% w/v sodium metabisulfite were evaluated by spectrophotometric and colorimetric assays on dried “Golden Delicious” apple slices. Based on HPLC analysis, the treated apple slices were enriched with bioactive compounds which effectively improved antioxidant capacity and limited enzymatic browning by increasing lightness, reducing color change, and inhibiting PPO activity. Hence, the juice of unripe grapes recovered as agricultural wastes during bunch thinning of vineyards could be proposed as a safe, inexpensive, and eco-friendly alternative to conventional antibrowning treatments in apple processing.     

Changes of contents and antioxidant activities of polyphenols during fruit development of four apple cultivars

Polyphenols are functional components in apples and can be separated into four groups by Sephadex LH-20 as epicatechin, procyanidolic oligomers, chlorogenic acid and procyanidolic polymers. Antioxidant activities of each group were determined by FRAP and DPPH radical scavenging assay. It was found that procyanidolic oligomers and procyanidolic polymers influenced the total polyphenols content (measured by Folin–Ciocalteu method) much more in Jonagold, Golden Delicious, Fuji and Guoguang four apple cultivars. The Fe-reducing activity of procyanidolic oligomers in the four apple cultivars increased significantly during the development while the other three compounds changed irregularly. And the Fe-reducing activities of epicatechin and procyanidin contributed much more to the total Fe-reducing activities during the fruit development in the four apple cultivars. The DPPH scavenging activities of four compounds in Jonagold and Golden Delicious decreased during fruit development and that of Fuji and Guoguang changed irregularly. Chlorogenic acid was the main contributor in Jonagold, Golden Delicious and Fuji to the total scavenging activity. In Guoguang, it was procyanidolic oligomers that contributed much to the total scavenging activity.