Factors leading to the expression of “framboisé” in French ciders

During the last decade, observations on cider production sites allowed for some hypotheses to be made concerning relationships between “framboisé” (cider-sickness) development and physical and chemical cider parameters as well as some process operations. Although Zymomonas mobilis has long been known to cause cider-sickness in British ciders, it had never been detected in France until recently from a number of “framboisé” cases.The possibility to trigger “framboisé” in cider by inoculation of the bacterium allowed for a better understanding of the factors leading to “framboisé” development in ciders. The stage of the malo-lactic fermentation, amount of dissolved of oxygen, pH, combined effect of pH and sulfur dioxide and residual amount of utilizable yeast nitrogen (YAN) were studied.The main factor affecting cider sensitivity to “framboisé” is the amount of YAN. If the amount of YAN is sufficient, the development of “framboisé” will mainly be influenced by pH (sulfur dioxide playing a minor role).     

Duplex PCR Method for Rapid Detection of Zymomonas mobilis in Cider

A duplex PCR method was developed for Z. mobilis species detection. Two sets of primers were used; the first one targeted a 530 bp region of the 23S rRNA gene, the amplified fragment corresponding to an internal control, while the second targeted a 900 bp region spanning the 16S and 23S rRNA gene regions and was Z. mobilis specific. This second primer pair was designed by comparison with corresponding sequences of a Sphingomonas sp., a bacterium that is phylogenetically the closest to Z. mobilis, and Gluconobacter oxydans that is taxonomically the closest relative found in cider. Results showed that the method was able to specifically amplify the two targets in all studied strains of Z. mobilis while only one fragment, corresponding to the internal control, was amplified for G. oxydans and the tested lactic acid bacteria commonly found in cider. The method threshold was determined by contaminating cider samples containing natural yeast and lactic acid bacteria flora. Within a 24 h period, ciders containing 10² CFU/mL of Zymomonas were detected as positives. The rapidity and reliability of this duplex PCR for detection of Z. mobilis directly from cider will certainly prove to be useful in detecting, early on during the fermentation phase, the presence of this spoilage microorganism. It will also be of interest as a complementary test when using the HACCP approach in the cider and beer industries.     

Microbial quality of “doubles” sold in Trinidad

A cross-sectional study was conducted to determine the prevalence and characteristics of Escherichia coli, Staphylococcus aureus, Bacillus spp. and Salmonella spp. in “bara”, “channa”, condiments/spices and ready-to-eat “doubles” sold by vendors in the St. George and Caroni counties of Trinidad. Of 196 samples of each of “bara”, “channa”, condiments/spices and ready-to-eat “doubles” examined, E. coli was detected in 0 (0.0%), 14 (7.1%), 96 (49.0%) and 67 (34.2%), respectively; Staphylococci were isolated from 104 (53.1%), 71 (36.2%), 129 (65.8%) and 123 (62.8%) samples, respectively; and Bacillus spp. were recovered from 22 (11.2%), 85 (43.4%), 100 (51.0%) and 88 (44.9%) samples, respectively. Salmonella spp. were not isolated from any sample. Of the 177 isolates of E. coli recovered from all sources, 9 (5.1%), 7 (4.0%) and 47 (26.6%) were mucoid, haemolytic and non-sorbitol fermenters (NSF), respectively, but none agglutinated with O157 antiserum. Of 427 staphylococcal isolates, 130 (30.4%) were confirmed as S. aureus of which 20 (15.4%) were haemolytic and 84 (64.6%) pigmented, while 17 (20.7%) of 82 strains of S. aureus tested produced enterotoxins. Ready-to-eat “doubles”, a popular food in Trinidad, therefore pose a potential health risk to consumers due to the high level of contamination with bacteria.     

Aromatic Profile of Ciders by Chemical Quantitative,Gas Chromatography‐Olfactometry,and Sensory Analysis

Nine samples of Asturias cider have been analyzed for volatile, olfactometric, and sensorial profiles. The aromatic composition was mainly constituted by fusel alcohols and ethyl esters. Among the minor volatile compounds, fatty acids, volatile phenols, and alcohols were the main components. The olfactometric analysis revealed the existence of 55 aromatic areas, exhibiting a wide range of intensities. Components like amyl alcohols, 2‐phenylethanol, ethyl esters such as 2‐methylbutyrate, hexanoate and octanoate, hexanoic and octanoic acids 2‐phenylethyl acetate, 4‐ethyl guaiacol, and 4‐ethyl phenol could be considered as being part of the structure of cider aroma. The extract dilution analysis of one extract identified 2 volatile phenols (4‐ethyl guaiacol and 4‐ethyl phenol) among the most powerful odorants in cider. These components gave significant correlations with the sensory attributes sweet, spicy, and lees.     

Effect of starter species on the content of some volatile aromatic compounds of kashkaval “Balkan” and kashkaval “Vitosha”

Four kinds of starter cultures created in this country were used for production of kashkaval “Vitosha” and kashkaval “Balkan”. In the process of ripening and storage of the products the changes of some aroma compounds taking part in flavour formation were followed besides acidity, pH and percentage of sodium chloride. Two of the aroma compounds, i.e. diacetyl and ethanol, were of outstanding importance for the quality of kashkaval “Vitosha”, whereas in respect to kashkaval “Balkan” such a relationship was not established. Inference was drawn that the product's flavour was dependent on starter culture and kind of milk.     

Effects of 1‐Methylcyclopropene and Hot Water Quarantine Treatment on Quality of “Keitt” Mangos

The optimal 1‐methylcyclopropene (1‐MCP) treatment to slow ripening of whole “Keitt” mangos, either alone or in combination with hot water treatment (HWT) (prior to or post 1‐MCP) was identified. USDA‐APHIS mandates that HWT can be used for control of fruit flies, but this may affect fruit response to 1‐MCP. Mangos were evaluated by repeated measurement of nondestructive firmness, peel color, and ethylene production on the same mango fruits during 2 wk of ripening at 20 °C after treatment. The magnitude of ethylene production increased as a result of both 1‐MCP and HWT. With softer mangos (65 N), treatment with 1‐MCP alone delayed fruit softening and extended the number of days to full‐ripeness (25 N) from 5 d in untreated fruit to 11 d. For these riper fruit, application of 1‐MCP prior to HWT extended the days to full‐ripeness to 9 d compared with 7 d when 1‐MCP was applied after HWT. With firmer mangos (80 N), 1‐MCP treatments alone prolonged the days to full‐ripeness to 13 d as compared to 11 d for the untreated fruit. There was no significant concentration effect on firmness retention among 1‐MCP treatments (0.5, 1.0, or 10.0 μL/L). HWT resulted in a faster rate of fruit softening, taking only 7 d to reach full‐ripeness. Combining 1‐MCP with HWT reduced the rate of softening compared to HWT alone, resulting in 9 to 11 d to full‐ripeness. Application of 1‐MCP before HWT showed a greater ability to reduce the rate of fruit softening compared with 1‐MCP treatment after HWT.     

“Potential Health Benefits of Lunasin: A Multifaceted Soy‐Derived Bioactive Peptide”

Bioactive peptides are small protein fragments derived from enzymatic hydrolysis of food proteins, fermentation with proteolytic starter cultures, and gastrointestinal digestion. These peptides have positive impacts on a number of physiological functions in living beings. Lunasin, a soy‐derived bioactive peptide, is one of the most promising among them. Lunasin encoded within 2S albumin (GM2S‐1) gene, identified as a novel peptide extracted from soybean seed. It is composed of 43 amino acid residues with a molecular weight of 5.5 kDa. Extensive scientific studies have shown that lunasin possesses inherent antioxidative, anti‐inflammatory, anticancerous properties and could also play a vital role in regulating of cholesterol biosynthesis in the body. Its high bioavailability and heat stable nature allow its potential use as dietary supplement. The present review summarizes some of the potential health and therapeutic benefits of lunasin reported hitherto.     

Impact of Microclimate on Fatty Acids and Volatile Terpenes in “Kerman” and “Golden Hills” Pistachio (Pistacia vera) Kernels

Pistachio is an economically important nut crop in California. Since temperature variations among geographical locations can influence biochemical processes during fruit development, it is of great relevance to understand the impact of growing area over the components that define the nutritional and sensory characteristics of pistachio nuts. Changes in moisture, fat content, fatty acid composition and volatile terpenes were studied during kernel development for “Kerman” and “Golden Hills” varieties in two different California Central Valley microclimates, Lost Hills and Parlier. Moisture content decreased from July to September for both cultivars at both locations. Kerman had a higher moisture content at both locations compared with Golden Hills. Harvest time affected fat content only for Kerman, where the values increased drastically from 21‐July to 4‐Aug, then remained constant. Golden Hills’ fat content remained constant during the period of the study. The main fatty acid in pistachio oil is oleic acid (46% to 59%), followed by linoleic acid (26% to 36%) and palmitic acid (11% to 16%). C16:0, C16:1, C18:2, and C18:3 decreased with harvest time, while C18:1 increased. α‐Pinene was the most concentrated volatile among the cultivars and locations. It decreased with harvest time for both cultivars at both locations, ranging from 105 to 2464 mg/kg. At harvest, Golden Hills and Kerman at Parlier both had higher concentrations of α‐pinene than the two cultivars at Lost Hills. Our results demonstrate that microclimate affects biosynthesis of fatty acids and terpenes in pistachio kernels, the main compounds responsible for pistachio nutritional and sensory characteristics.     

Enhancing the Microbiological Stability of Malt and Beer — A Review

While beer provides a very stable microbiological environment, a few niche microorganisms are capable of growth in malt, wort and beer. Growth of mycotoxin‐producing fungi during malting, production of off‐flavours and development of turbidity in the packaged product due to the growth and metabolic activity of wild yeasts, certain lactic acid bacteria (LAB) and anaerobic Gram negative bacteria, impact negatively on beer quality. It follows that any means by which microbial contamination can be reduced or controlled would be of great economic interest to the brewing industry and would serve the public interest. There has been an increasing effort to develop novel approaches to minimal processing, such as the exploitation of inhibitory components natural to raw materials, to enhance the microbiological stability of beer. LAB species, which occur as part of the natural barley microbiota, persist during malting and mashing, and can play a positive role in the beer‐manufacturing process by their contribution to wort bioacidification or the elimination of undesirable microorganisms. Other naturally occurring components of beer that have been valued for their preservative properties are hop compounds. It may be possible to enhance the antimicrobial activities of these compounds during brewing. Some yeast strains produce and excrete extracellular toxins called zymocins, which are lethal to sensitive yeast strains. Yeast strains resistant to zymocins have been constructed. Imparting zymocinogenic activity to brewing yeast would offer a defence against wild yeasts in the brewery. Thus, the antimicrobial properties of naturally occurring components of raw materials can be exploited to enhance the microbial stability of beer.     

Scombroid poisoning. Isolation and identification of “saurine”

A number of samples of fish which were involved in allergy-like food poisoning incidents were examined for the presence of “saurine”, a toxin reported to be the causative agent in scombroid poisoning. Chromatograms of extracts developed in acidic solvents showed two distinct areas which possessed vagal stimulating activity with guinea pig ileum. Both these areas contained histamine and this suggests that “saurine” is a histamine salt.     

Gas chromatographic–mass spectrometric characterisation of the Italian Protected Designation of Origin “Altamura” bread volatile profile

Dynamic headspace extraction technique coupled to the gas chromatography–mass spectrometry analysis was applied to characterize volatile compounds of both crust and crumb of the Protected Designation of Origin Italian durum wheat sourdough “Altamura” bread. Volatile compounds of crust and crumb were characterized and statistically compared and their relative abundance was also calculated. A total of 89 compounds belonging to different chemical classes were identified in the crust. More abundant compounds detected in the crust were ethanol (20 ± 6%), 2-furfural (14 ± 7%) and 3-methyl-1-butanol (9 ± 5%). A lower number of volatile compounds (74) was identified in crumb, among which ethanol (32 ± 7%), 3-methyl-1-butanol (23 ± 6%) and 3-pentanol (7 ± 3) were the most abundant. The influence of different baking modes (wood- or gas-fired) on volatile compounds, macroscopic appearance and selected physico-chemical parameters (colour and texture) of bread samples were also evaluated.

Samples baked in wood-fired oven showed larger amount of volatile compounds such as furans and aldehydes that could positively influence the flavour of the product.

Crust of wood-fired breads showed higher amounts of compounds from Maillard reaction, resulting in harder and browner breads than gas-fired samples. Macroscopic appearance of crumb of wood-fired breads showed higher percentages of larger pores, being also less hard and cohesive than gas-fired samples.     

Impact of Annealing on the Physicochemical Properties of Unfermented Cassava Starch (“Polvilho Doce”)

Unfermented cassava starch (“polvilho doce”) was subject to annealing treatment at 50°C for 24, 48, 96, 120, 168 and 192 h, in 1:5 starch to water ratio. The annealing treatment changed the internal structure of “polvilho doce” at increasing treatment time. Peak viscosities decreased significantly, denoting that there was a decrease in leaching of amylose from the granules. The pasting temperatures were increased, setback and breakdown were reduced while hold and final viscosities increased, showing an improvement of the stability of the paste. Swelling power and solubility were reduced at all temperatures and the solubility at 55°C was zero after 120 h of treatment. The DSC data for T_o, T_p, T_c and ΔH increased and the gelatinization range was narrowed. The X‐ray diffractograms changed from C_A to A pattern (samples annealed for 48, 96, 120, 168 and 192 h), denoting an increase in organization of double helices of amylopectin. Annealing imparts to the samples some waxy starches characteristics which can be very useful in the food industry.