Market testing of a major cassava flour product in the Accra metropolitan area*

The current study analyses consumer judgements about some existing as well as newly introduced brands of a processed cassava food product (fufu flour) by means of market testing. Except for colour, the respondents’ evaluation of the sensory attributes of the various fufu flours that they have consumed did not have much significant differences. Also, no significant differences in sensory attributes were identified when the fufu flour brands were compared with traditional fufu, except for hand‐feel, smoothness and elasticity. In addition, no significant differences were observed in the prices of the various fufu flour brands in comparison with the equivalent price of traditional fufu. The study finds diversification of the marketing outlet for fufu flour as a major factor that could contribute to improving the awareness of the product.     

A socio‐economic assessment of cowpea diversity on the Ghanaian market: implications for breeding

Given the importance of cowpea [Vignaunguiculata(L)Walp] in fighting malnutrition and poverty, a socio‐economic assessment of cowpea diversity found on the Ghanaian market was conducted. The objective was to investigate emerging consumer preference for cowpea and make recommendations for the development of tailor‐made varieties. Forty‐seven cowpea accessions were collected from traders interviewed for morphological characterization to ascertain the degree of diversity. Data was subjected to Hierarchical Cluster Analysis using Genstat Discovery Edition 3 software and variations among the cowpea varieties based on the selected seed traits established. Cowpea varieties found on the markets were broadly categorized into foreign and local varieties and usually named after their sources. Foreign Cowpea varieties were very popular on the markets surveyed as reflected in the per cent distribution of respondents by cowpea varieties sold; Niger (52%), Burkina Faso (50%), Togo (46%), Lagos (36%) and Ghana (18–21%). At the trader level, the order of preference for cowpea characteristics was cleanliness (stone free and no dirt), colour (white seed colour), easy to cook, taste, size, less weevil damage, dryness and place of origin ranked in decreasing order of importance. At the consumer level, cleanliness that was also tied to the extent of weevil damage was ranked most important. This was followed by seed colour (preferable white), short cooking time, size and taste. From the sociological perspective, concerns are raised on the impact of past cowpea breeding activities giving the level of competitiveness and market performance of locally improved varieties observed. Recommendation is made for traders and consumers to be considered as relevant actors in all the stages of crop improvement and breeding activities. This is crucial for enhanced small‐holder farmer market access and strengthened food networks in rural economies.     

藤椒气调贮藏品质变化规律的研究

为了解气调贮藏环境条件下藤椒感官品质的变化情况,研究(2±1)℃贮藏温度和气调处理对贮藏过程中藤椒的色泽、气味、滋味、油腺和新鲜度的影响情况。结果表明:在(2±1)℃、相对湿度90%~95%,5%O_2+5%CO_2条件下,贮藏5 d内,感官几乎无变化,贮藏6 d藤椒油开始发黑,色泽有发黄变黑现象,新鲜度逐步开始下降,气味、滋味开始减弱。第10 d普遍出现发黑现象。第15 d全部出现发黑现象,完全失去商业价值。     

Sraffian Thoughts in Full Marginalist Dress

In the single‐products economy considered here, every industry has a constant‐elasticity‐of‐substitution unit cost function; moreover that constant‐elasticity‐of‐substitution is the same for each industry (0 < σ < 1). When this strongly ‘marginalist’ system is looked at from a Sraffian perspective, it is found that some significant properties of the system are not in line with normal marginalist expectations.     

Convergence of optimal expected utility for a sequence of discrete‐time markets

We examine Kreps' conjecture that optimal expected utility in the classic Black–Scholes–Merton (BSM) economy is the limit of optimal expected utility for a sequence of discrete‐time economies that “approach” the BSM economy in a natural sense: The nth discrete‐time economy is generated by a scaled n‐step random walk, based on an unscaled random variable ζ with mean 0, variance 1, and bounded support. We confirm Kreps' conjecture if the consumer's utility function U has asymptotic elasticity strictly less than one, and we provide a counterexample to the conjecture for a utility function U with asymptotic elasticity equal to 1, for ζ such that .     

Influences of visual attributes of food packaging on consumer preference and associations with taste and healthiness

Two experiments designed to investigate how the shape and colour of packaging, and product category, conjointly impact consumers’ product and packaging expectations are reported. In Experiment 1, the shape (rounded vs. angular) and visual appearance (greyscale, red‐to‐yellow and blue‐to‐green colour schemes) of the packaging were manipulated. Dependent measures were preference (willingness to purchase the product, how attention‐capturing the packaging is, and the pleasantness of the design) and any taste associations. In Experiment 2, shape (rounded vs. angular), colour (red‐to‐yellow vs. blue‐to‐green colour schemes), and product category (buttery vs. cereal cookies) were manipulated. In this case, the dependent measures were the perceived product healthiness and the preference of consumers. The results of Experiment 1 revealed that packaging colour influenced product preference. Red‐to‐yellow and blue‐to‐green colour schemes and angular packaging were preferred over greyscale and round packaging. Colour also influenced taste associations, while shape only influenced ratings of expected sweetness. In Experiment 2, packaging shape and product category influenced product preference. In particular, rounded packaging and the packaging of buttery cookies were preferred over angular packaging and the cereal cookies packaging. The healthiness of the product was rated higher for the rounded and red‐to‐yellow packaging containing a buttery product. Taken together, these results highlight the important role played by colour, shape, and category on the expectations and associations elicited by viewing product packaging.     

Comparative study of properties and acceptability of Haitian and US honey‐roasted peanuts

A honey‐roasted peanut product, flavoured with ginger and anise, was recently developed in Haiti in an effort to increase the consumption of locally grown peanuts. The objective of this study was to compare quality and consumer acceptability of the Haiti product with a traditional US‐manufactured brand. Haitian panellists (199) evaluated colour, appearance (dry/oily), crunchiness, peanut flavour and sweetness of the products using five‐point just‐about‐right scales. Colour (Minolta chromameter), hardness (TA.XT2i texture analyser fitted with a TA42 knife blade) and moisture (Denver IR‐30 moisture analyser), lipid (ethyl ether extraction) and sugar (Dionex DX‐500 high pressure liquid chromatography system) contents of the products were also determined. The Haiti product was significantly (P < 0.05) darker brown, harder and contained more (P < 0.05) sucrose and glucose but less (P < 0.05) lipid and fructose than the US product. Panellists indicated that crunchiness, peanut flavour and sweetness of both products were just right. The US product had acceptable appearance but was rated too light (hue angle = 69.6 ± 0.70, L‐value = 58.2 ± 0.47) in colour, whereas the Haiti product appeared too dry and dark (hue angle = 62.6 ± 2.79, L‐value = 44.6 ± 2.22). The Haiti peanuts were not deskinned, and their testae may have decreased the acceptability of the product's appearance and colour. The Haiti product was significantly (P < 0.05) just right to the female panellists and to the 21‐year plus panellists from all income groups. Deskinning of the peanuts and increased oil addition during roasting may improve the acceptability of the Haiti product, especially to 14–20 year olds. Decrease in sugar content may also make the Haiti product more appealing to this age group and to male Haitians.     

How important is appearance? Consumer preferences for mandarins in Indonesia

The purpose of this research was to determine consumer preferences for attributes of mandarins in Indonesia, in particular the preferences between domestic and imported mandarins. A focus group was conducted to identify some salient attributes of mandarins to Indonesian consumers. Intrinsic fruit attributes that are important to consumers include the appearance, taste, texture and overall quality of fruit segments and skin colour. Based on the results of the focus group, a survey questionnaire was developed and used in the interview process with the consumers. Evaluations were made on a seven‐point intensity scale for two domestic lines of mandarins and one imported line. Respondents did not know the origins of the fruit when evaluating the intrinsic qualities of mandarins. The results from 113 respondents in the city of Surabaya showed that domestic mandarins were rated higher on all intrinsic attributes. Imported mandarins were rated the best only on skin colour as domestic fruit are normally green or only partially orange when ripe. The fact that imported mandarins continue to command premium prices in the Indonesian market is an interesting phenomenon. Two possible explanations are suggested. The prestige of supermarket retailers (where imported produce is mostly sold) may advantage imported fruits. Alternatively, consumers may hold persistently favourable perceptions of imported fruits. Whether this represents the influence of subjective psychological and status factors requires further investigation.     

Older people and convenience in meal preparation: a European study on understanding their perception towards vegetable soup preparation

A sample of 768 seniors over 65 years, living in eight European countries, was interviewed to investigate perceptions, preferences and attitudes towards convenience in preparation of vegetable soups. In each country, a range of seven vegetables soups varying in preparation levels required before consumption was identified. The first part of the interview (in‐depth interview) was carried out by using the Repertory Grid Method, an effective method to describe perceptions of foods using consumers' own language. Overall, vegetable‐related foods with convenience in preparation were perceived in similar ways across the countries. Older adults tended to describe ready vegetable soups mainly making associations related to preparation, rather than on their own preferences and evaluations. Conversely, fresh vegetables requiring all preparation or considerable preparation (cut fresh vegetables) were mainly associated with attributes such as taste, freshness, health benefits and familiarity with the product. The second session of the interview was based in part on the Theory of Planned Behaviour. A component measuring the extent to which it is felt necessary to eat convenience foods (perceived need) was assessed as well. Generally speaking, older people did not seem to view positively the consumption of convenience foods. Additionally, they did not feel the need to consume these products nor do they have the intention to consume them in the forthcoming month. Pleasure associated with performance of the behaviour was the most important determinant of intention to eat convenience foods in Germany, Denmark and Sweden. Perceived need was the most important factor in determining the intention to eat convenience foods in the UK, Poland and Portugal. Perceived control and subjective norms were the most important factors influencing the intention to eat convenience foods in Italy. The encouragement of consuming ‘ready‐meals’ might represent an opportunity to have healthier food choices and to reduce the risk a monotonous diet for older people who cannot or do not know how to cook, combined with a low interest in food‐related activities such as cooking.     

The acceptability of different types of soymilks available in Cape Town in consumers from high and low socio‐economic areas

The aim of this study was to determine the knowledge and acceptability of soymilk (defined as consumption pattern/usage and taste) by adult consumers, residing in different socio‐economic areas (low vs. high) in Cape Town. The study population of 214 participants were selected using convenience sampling. A questionnaire was developed in order to obtain demographic data (four items); basic general knowledge of soymilk (four items); and acceptability of the tested products (consumption patterns and taste) (eight items). There was a significant difference between the two groups (P = 0.000) regarding basic knowledge of soymilk, with significantly more in the high socio‐economic area (HSEA) having a score of at least 75%. Gender (P = 0.082) and age (P = 0.122) did not have a significant impact on the consumption patterns of soymilk. There was no significant difference between the two groups with respect to current usage (P = 0.228) and frequency of use (P = 0.213) of soymilk. However, a significantly smaller group (P = 0.000) of participants in the low socio‐economic area had previously tasted soymilk compared with those in the HSEA (16.7% vs. 41.5%; P = 0.000). In conclusion, socio‐economic status appeared to be associated with knowledge of soymilk. No significant differences with regard to gender, age or current usage in the two groups studied were noted.     

Sensory evaluation and physico‐chemical measurements of tomatoes commonly consumed in New Zealand

Five different locally sourced commercially grown tomatoes (cultivars; Aranca, Excell, Flavourine, Mondeo and Solairo) and one grown in Australia (Gourmet) were subjected to sensory evaluation using a consumer taste panel. Physico‐chemical characteristics (CIE colour, dry matter, °Brix, titratable acidity, pH and °Brix : acid ratio) were also measured on the tomatoes. Overall, the sensory evaluation results showed that there were differences between the tomato cultivar most likely to be purchased (Excell, bright red skin colour) and the tomato liked most overall (Aranca, darker red skin colour). Panellists gave a wide range of juiciness and hardness scores to the tomatoes evaluated. Cultivars Flavourine, Aranca and Solairo were moderately sweet while Excell, Mondeo and Gourmet were regarded as not sweet at all. Physico‐chemical results showed that the New Zealand grown tomato varieties evaluated were comparable with other tomatoes grown in New Zealand while most tomatoes were redder and had higher titratable acidity compared with studies of tomato varieties from other countries. The panellists initially ranked the tomatoes on the redness of skin colour but changed their rankings when they had assessed their taste and texture.     

Study of Consumer Preferences in Regard to the Blonde Orange Cv. Washington Navel “Arancia Di Ribera PDO”

Consumers’ attitude and preferences in regard to food ingredients, country of origin, social corporate responsibility toward the environment, and work conditions have changed over the last 10 years. Consumers are getting more educated and therefore more sensitive around cultivation practices in agriculture and food processing, which increases concerns in regard to production practices in agriculture. Several studies have been conducted on consumers’ preferences about quality food, but not with regard to blonde oranges cv. Washington Navel cultivated in southern Italy. This quality fruit is a niche product that achieved the Protected Designation of Origin (PDO) certification for high organoleptic properties and fine taste. In this study, by a survey of 400 Italian consumers, we discovered preferences in regard to the cv. Washington Navel PDO (Riberella) attributes and revealed variables that may influence consumers’ purchasing behavior. Cluster analysis, based on respondents’ rates on 20 attributes, revealed preference segmentation. Freshness, taste, and origin were the most important attributes for consumers, following visual appearance and quality/price ratio. In responding to the demands of consumers for quality fresh fruit, information about quality standards and about the Riberella PDO is poor. Therefore, there may be potential to develop specific policies and marketing strategies to product the position in the international market.     

Effect of deep‐fat frying of potato chips and chicken on the quality of soybean oil

The type of products may affect the quality of oil during deep‐fat frying. The quality changes in pure soybean oil during frying of potato chips and chicken drumsticks were evaluated and compared. The oil was subjected to continuous frying at 180°C for a period of 315 min. The parameters used to assess the oil quality were peroxide value (PV), iodine value (IV), free fatty acids (FFA), refractive index (RI) and colour. The percentage of oil absorbed by the two products was determined. The oil was also assessed visually for any change in colour, viscosity, turbidity, flavour and deposit. Results showed that, for both products, PV, IV, FFA, RI and colour changed significantly with time (P < 0.05). Potato absorbed oil during frying (6.9%), whereas chicken released fat into the frying medium (2.4%). When the rates of change of the various parameters in the oils were compared for the two products, significant differences (P < 0.05) were noted for PV and colour only. The oil used during the frying of chicken appeared visually to be at a more advanced stage of deterioration.     

Effects of selected antioxidants on physical and sensory characteristics of yeast bread containing flaxseed meal

Flaxseed has been identified as a potential functional food because of its high content of phytochemicals, alpha‐linolenic (α‐linolenic) acid and lignans. Flaxseed can be used in baked goods because of its minimal loss of α‐linolenic acid. Alpha‐linolenic acid is susceptible to oxidation and the development of off‐aromas and flavours in the food. The focus of this study was to determine the effectiveness of both synthetic and natural antioxidants that were incorporated into a yeast bread that contained 15% flaxseed as a partial replacement for bread flour. The study evaluated the effectiveness of the antioxidants on the physical and sensory characteristics of the bread. Physical properties, such as per cent moisture and loaf volume, were not affected (P > 0.05) by the antioxidants, but ascorbic acid, butylated hydroxytoluene and butylated hydroxyanisole, independently, had a softening affect (P < 0.05) on crumb firmness. Sensory analysis indicated significant (P < 0.05) changes in aroma, grainy taste, aftertaste and moistness in all bread samples regardless of antioxidant, however, only ascorbic acid was rated as effective in maintaining a softer (P < 0.05) crumb.     

Slicing,Dicing, Spicing,and Pricing: Factors Influencing Purchase and Consumption of Fresh Potatoes

To better understand potential reasons for a North American decline in fresh potato consumption, a region-wide survey (n = 1009) was undertaken in eastern Canada. Results were examined comparing high- and low-frequency potato users on a variety of factors, including beliefs, attitudes, barriers, needs, and satisfaction with potatoes. Respondents indicated positive perceptions pertaining to potato nutrition, taste, preparation, and overall enjoyment. Multiple logistic regression analysis suggested two variables—age and the perceived importance of potatoes for the everyday meal—were strong predictors of high versus low frequency of potato consumption. Respondents judged the ability to see the potato in the package, potato firmness, and locally produced as point-of-purchase characteristics particularly important when buying fresh potatoes. However, respondents also indicated that their needs were not fully met and expressed relatively low levels of satisfaction when purchasing potatoes. Based on the results, suggestions are provided for improving the marketing of fresh potatoes.     

An explicit partial‐equilibrium model to justify the Generalized Marshall‐Lerner condition (GML)

Robinson's derivation of the Marshall‐Lerner condition (ML) is more general in that she considers a situation where initially the trade balance is not in equilibrium with the incorporation of the supply curves of exporters. This paper examines a partial equilibrium analysis of a country's imports and exports markets within a theoretical model which considers both the demand and supply sides in these two internationally traded‐goods markets. The aim here is to show explicitly how the Generalized Marshall‐Lerner condition (GML) of Robinson can be obtained. We examined the two effects of the nominal depreciation of the domestic currency on the trade balance: the volume effect and the value effect and how they counterbalance each other. We found that the standard Marshall‐Lerner condition (ML) was not sufficient when the trade balance was initially in deficit and it was also not necessary if the trade balance showed an initial surplus. Moreover, this study provides a new interpretation for Robinson’ sufficiency condition where the trade balance must improve following a nominal depreciation of domestic currency when the elasticity of foreign demand exceeds the ratio of imports to exports. This paper also examines the situation of a small open economy which could not influence the world prices where the foreign demand for exports and the foreign supply of exports are infinitely large. Finally, there is a discussion on two policy implications for exchange rate regulation: the amount of devaluation that is necessary to improve a given trade imbalance as a governments intervention and additional support for the slow improvement of the trade balance in the short run after a devaluation policy known as the J‐Curve effect.     

An Exploration of U.S. Consumer Perceptions and Affect: Two Forms of a Soy-Based Food Product

ABSTRACT

This article focuses on a consumer comparison of fresh tofu and frozen tofu, and the investigation of consumer perceptions of and responses to, both products. A literature review of consumer perceptions and attitudes toward soy products was carried out. Consumer perceptions and affect were then qualitatively investigated using separate focus groups composed of “soy-users” and “health conscious” consumers. Extensive taste tests of the product, using five different recipes, comparing and contrasting frozen versus fresh forms of tofu were conducted to obtain sensory evaluations. The results indicate that many consumers are unfamiliar with the product, yet tofu is perceived to be an acceptable food for those inclined to use soy-based products, as well as those who are otherwise healthy eating conscious. In taste tests, it was found that the recipes in which tofu was disguised were preferred. In addition, frozen tofu was generally found not to be perceived as markedly different from the fresh product. Implications of the findings for marketing fresh and frozen forms of tofu are discussed.     

BUY‐LOW AND SELL‐HIGH INVESTMENT STRATEGIES

Buy‐low and sell‐high investment strategies are a recurrent theme in the considerations of many investors. In this paper, we consider an investor who aims at maximizing the expected discounted cash‐flow that can be generated by sequentially buying and selling one share of a given asset at fixed transaction costs. We model the underlying asset price by means of a general one‐dimensional Itô diffusion X , we solve the resulting stochastic control problem in a closed analytic form, and we completely characterize the optimal strategy. In particular, we show that, if 0 is a natural boundary point of X , e.g., if X is a geometric Brownian motion, then it is never optimal to sequentially buy and sell. On the other hand, we prove that, if 0 is an entrance point of X , e.g., if X is a mean‐reverting constant elasticity of variance (CEV) process, then it may be optimal to sequentially buy and sell, depending on the problem data.     

Pairs‐trading and spread persistence in the European stock market

In this paper, we adapt the demand and supply framework introduced by Figuerola‐Ferretti and Gonzalo (Journal of Econometrics, 2010) to illustrate the dynamics of Pairs‐trading. We underline the process by which a finite elasticity of demand for spread trading determines the speed of mean reversion and pairs‐trading profitability. A persistence‐dependent trading trigger is introduced accordingly. Applied to STOXX Europe 600–traded equities, our strategy exploits price leadership for portfolio replication purposes and delivers Sharpe ratios that outperform the benchmark rules used in the literature. Portfolio performance and mean reversion are enhanced after firm fundamental factor restrictions are imposed.     

Cross‐modal Interactions between Color and Texture of Food

Color has a profound influence on human perception. Not only does it cause changes in physiological or emotional states, it can shape what is perceived in other sensory modalities. However, the body of research on these “cross‐modal” experiences has predominantly examined color's influence on taste and smell. As such, the aim of this study was to identify the cross‐modal influence of color on the sense of touch. In four experiments involving food products, the cross‐modal interaction between color and texture was found to be automatic, unlearned, and a moderating effect on perceived texture. Furthermore, results indicate a person's haptic predisposition, or “need for touch,” influences their sensitivity to these cross‐modal effects. This research builds on current theory involving color, presents a number of areas for future research, and discusses managerial implications of color–texture cross‐modal interactions.