Amauri Rosenthal

Consumer attitude towards information on non conventional technology

Abstract The increasing demand for healthy and nutritious products as a consequence of consumers being better educated and more demanding, contributes to a continuous need for new products, and a more differentiated food product assortment. Many consumers are choosing foods closer to those ‘in natura’. This scenario contributes to the development of emerging technologies which may lead to the availability of products with better sensory and nutritional quality. However, the concern about the acceptance of such products becomes an important factor during their developments. This study aimed at evaluating the consumer attitude towards the information presented on the label about the technology used for the fruit juice processing — high pressure — by Brazilian consumers. Focus group sessions were conducted with students and housewives to obtain information about consumers’ awareness, attitudes, opinions, behaviours, and concerns toward processed foods and beverages, and to provide strategies that could aid in marketing products. A protocol delineating the sequence of question to be asked in each focus group was designed beforehand and applied to each group. Discussions were conducted with two groups each of students and of housewives. Pineapple juice labels were created by varying the nutritional, sensory, and technological information about the product were used to motivate the discussion. Although the participants in this study were very different in terms of age and level of education, most of their perceptions about the pineapple juices were similar. The students and the housewives considered the information about the technology an important factor during the product evaluation, however, the employed ladies who worked at the administrative side of a food research institution asked for more explanation about the technology in order to show the benefits it could provide to consumers.

Non conventional technologies and impact on consumer behavior.

Abstract Consumers are becoming more conscious about the potentially negative impact of food processing on human health and the environment. In particular, there is increased public concern about the application of emerging technologies such as genetic modification to food production, particularly with respect to consumer perceptions of potential for negative impact of genetically modified organisms on ecology. However, less is understood about consumer acceptance of potentially controversial technologies where such technological innovation replaces traditional manufacturing methods, which themselves have the potential for environmental harm. In the present study, consumer acceptance of a genetically modified product was examined. In this research, the process of genetic modification had the potential for reducing the environmental impact caused by the alternative, traditional method of production. The analysis took account of the effects of other factors such as reduced price and brand in consumer decision making, as well as the provision of information about manufacturing process. The product investigated was vegetable oil. One hundred and sixty five consumers evaluated the relative importance of different combinations of manufacturing process (traditional process, versus genetic modification) as well as the commercial brand (familiar versus unknown), price (low v ersus high) and label image (sunflower versus an image of a green globe indicating environmental friendliness), on purchase intentions. The data were analysed using conjoint and cluster analyses. Three clusters of consumers were identified. The first cluster (11% of the sample) based the purchase intention decisions on the label the image. The second one (25% of the sample) preferred environmentally friendly oil, highly priced and branded as Mazola. The third cluster (19% of the sample) considered mainly information about manufacturing process as of importance to their decision about purchases. In particular, these consumers preferred products associated with information about “environmentally friendly processing methods”. The results are compared with a similar sample of British respondents, and the implications of cross-cultural differences discussed.

Influence of package, type of apple juice and temperature on the production of patulin by Byssochlamys nivea and Byssochlamys fulva.

Although the production of patulin in apple fruits is mainly by Penicillium expansum, there is no information on the ability of heat resistant moulds that may survive pasteurization to produce this mycotoxin in juice packages during storage and distribution. In this study, the production of patulin by Byssochlamys spp (Byssochlamys nivea FRR 4421, B. nivea ATCC 24008 and Byssochlamys fulva IOC 4518) in cloudy and clarified apple juices packaged in laminated paperboard packages or in polyethylene terephthalate bottles (PET) and stored at both 21 degrees C and 30 degrees C, was investigated. The three Byssochlamys strains were able to produce patulin in both cloudy and clarified apple juices. Overall, the lower the storage temperature, the lower the patulin levels and mycelium dry weight in the apple juices (p<0.05). The greatest variations in pH and degrees Brix were observed in the juices from which the greatest mycelium dry weights were recovered. The maximum levels of patulin recovered from the juices were ca. 150 microg/kg at 21 degrees C and 220 microg/kg at 30 degrees C. HPLC-UV, HPCL-DAD and mass spectrometry analyses confirmed the ability of B. fulva IOC 4518 to produce patulin. Due to the heat resistance of B. nivea and B. fulva and their ability to produce patulin either in PET bottles or in laminated paperboard packages, the control of contamination and the incidence of these fungi should be a matter of concern for food safety. Control measures taken by juice industries must also focus on controlling the ascospores of heat resistant moulds.

Heat resistance and the effects of continuous pasteurization on the inactivation of Byssochlamys fulva ascospores in clarified apple juice.

Aims:  To determine thermal resistance, the effect of pasteurization temperature variations (c. 2°C) in a continuous system in the number of decimal reductions (n) of a Byssochlamys strain in clarified apple juice (CAJ).

Effect of enzymatic treatment and filtration on sensory characteristics and physical stability of soymilk

Abstract Several hydrolytic enzymes––Celluclast 1.5L, Pectinex ultra sp, Rohalases (SEP, F, 7069 e 7118)––and filtration with different pore size tissues––20; 30; 85; 100 μm––were independently studied, regarding their effect on the sensory quality of whole soymilk. The whole soymilk process included the following operations: dehulling, boiling, draining, grinding, homogenisation, enzymatic treatment or filtration, and heat treatment. The treatment with Celluclast 1.5L or filtration using a 20-μm tissue resulted in a considerable reduction of the particle size suspended in the soymilk. Such reduction originated products with low levels of sensory attribute of chalkiness and higher physical stability, in comparison to the control submitted to either one or two homogenisations. The enzymatically treated soymilk resulted in a higher global impression of flavour than the filtered product and the products submitted to one and two homogenisations, respectively.

Use of a logistic model to assess spoilage by Byssochlamys fulva in clarified apple juice

The percentage P (%) of spoiled bottles (n=40) of clarified apple juice due to Byssochlamys fulva, was modeled by using a logistic model: P = P(max)/1 + exp (k(tau-t)) where P(max) (%) the maximum percentage of spoiled bottles, k (h(-1)) a slope parameter and tau (h) the time for P=P(max)/2. Bottles of pasteurized apple juice were inoculated with B. fulva IOC 4518 ascospores for low and high initial loads, 4.8+/-2.3 ascospores/100mL and 19.3+/-4.6 ascospores/100mL respectively and incubated at 21 degrees C and 30 degrees C. P(max) was not significantly different from 100% except for a low initial load at 21 degrees C. Model parameters were estimated with a good accuracy, RMSE in the range 3.89-7.50. Then the model was used to determine the time for 10% bottles spoiled, t(10%). This time was greater at low initial loads, 57.4 and 104 h at 30 and 21 degrees C respectively, than at high initial loads 23.9 and 75.1h at 30 and 21 degrees C respectively. This study demonstrated that even at a very low initial contamination, clarified apple juice can be easily spoiled by B. fulva highlighting the importance of controlling critical control steps of fruit juice processing (i.e., fruit washing, juice filtration and pasteurization).

The Effect of Extrinsic Product Attributes of Pineapple Juice on Consumer Intention to Purchase

This study aimed to investigate the extent to which consumer information concerning several attributes of the pineapple juice packaging, including the manufacturing process, influenced the consumer intention to purchase. It is suggested that high-pressure technology retains nutrients as vitamins and keeps sensory attributes closer to those of fresh foods. These advantages meet the increasing consumer demand for healthy products and a more differentiated food assortment. However, the benefits provided by these products are not always communicated to consumers. Although information about the technology (high-pressure) had been positively considered by consumers when fruit juice consumption was taken into account, fewer studies have focused on this aspect. The effect of 5 attributes of the package (information on manufacturing process, product definition, production information, price, and brand name) on the pineapple juice consumer intention to purchase was investigated by 96 fruit juice consumers. Information about technology (high-pressure) positively contributed to the consumer pineapple juice intention to purchase and showed to be essential when it is applied on pineapple juice production, being a useful approach when adequately communicated to consumers.

Produção de 'leite' de soja enriquecido com cálcio

SUMMARY PRODUCTION OF CALCIUM ENRICHED SOYMILK. Soymilk is a high nutritional product. It has high level of protein and it is an excellent substitute for those people who are not able to drink cow milk due to lactose intolerance. However, soymilk has low content of calcium, an important mineral for the production and maintenance of the bones. Consequently, it is required the addition of such mineral into the soymilk, in order to improve its nutritional value. This study aimed at producing soymilk added with calcium, with adequate sensory quality. Sensory tests were carried out by a selected and trained panel from Embrapa Food Technology to identify the more suitable calcium salt, which would be added to the product. The following sensory attributes were evaluated by the panel: chalkiness, beany flavour, body, off – flavour and global quality. The losses during the soymilk processing were investigated. Tricalcium phosphate yielded the highest sensory quality product for the trained panel. The sample with calcium lactate presented the lowest loss of the mineral during the processing, followed by the calcium quelate. However, it has been noticed a phase separation in the former. Despite the soymilk added with calcium quelate had presented off-flavour, it was chosen because this form of calcium is described as ideal to enrich food, due to its high solubility and bioavailability. The off-flavour perceived in this beverage by the assessors, can be masked using natural flavourings, such as strawberry, chocolate, and vanilla.

Comparative Study of the Effects of Citral on the Growth and Injury of Listeria innocua and Listeria monocytogenes Cells

This study investigates the effect of citral on growth and on the occurrence of sublethal damage in Listeria innocua Serovar 6a (CECT 910) and Listeria monocytogenes Serovar 4b (CECT 4032) cells that were exposed to citral as a natural antimicrobial agent. Two initial inoculum concentrations were considered in this investigation: 102 and 106 cfu/mL. Citral exhibited antilisterial activity against L. innocua and L. monocytogenes, and the observed effects were dependent on the concentration of citral present in the culture medium (0, 0.150 and 0.250 μL/mL) (p ≤ 0.05). L. innocua had a shorter lag phase than L. monocytogenes, and the two species had nearly identical maximum specific growth rates. These results indicate that L. innocua could be used as surrogate for L. monocytogenes when testing the effects of this antimicrobial. Significant differences in the lag phase and growth rate were observed between the small and large inoculum concentration (p ≤ 0.05). Citral-treated L. innocua and L. monocytogenes that were recovered on selective medium (i.e., TSA-YE-SC) had a shorter lag phase and a higher maximum specific growth rate than cells that were recovered on non-selective medium (i.e., TSA-YE) (p ≤ 0.05). This result suggests that damage occurs at sublethal concentrations of citral.

Alterações oxidativas (cor e lipídios) em presunto de peru tratado por Alta Pressão Hidrostática (APH)

The High Hydrostatic Pressure (HHP) is an innovative food technology which uses high pressure (100 a 900 MPa) and has the advantage over conventional thermal technologies of keeping the sensory characteristics of food similar to the original characteristics ensuring the food safety, from the microbiological point of view, for an increased shelf life. This study aimed at investigating the effects of high pressure on the oxidative process, particularly on the lipid oxidation, and their effects on the color of pressurized turkey ham when treated from 200 to 400 MPa for 5, 10, and 15 minutes at room temperature. From the results, one can observe that no significant difference (p > 0.05) was found between the control and pressurized samples for the TBA indexes, but a difference was observed in the peroxide index on the 30th day among the samples. It was also observed change of color due to oxidative reactions after 45 and 65 days of storage in the samples treated under pressures of 400 MPa for 5 and 15 minutes