ACEROLA's CLONES OF INDUSTRIAL INTEREST

In order to know which clone of acerola is better for acerola industrialization, we studied the pectin methylesterase (PME) specific activity, pectin content and vitamin C content in five different clones of acerola. The pectin yield varied from 1.37 to 2.99% and the highest content of pectin occurred in clones 3 and 5. Ascorbic acid varied significantly from 1157.5 to 1735.5 mg/100 g of pulp in the five clones. The highest content of vitamin C occurred in clone 4. The PME specific activity varied from 0.79 to 2.92 units g ^?1 /g of pulp and the highest values occurred in clone 2. We also studied the optimum temperature and the optimum pH of this enzyme. Clones 1, 2, 4 and 5 showed optimum temperature at 90C. Clone 3 showed practically the same specific activity at all temperatures studied. Clones 1 and 4 showed an optimum pH of 9.0 and clone numbers 2, 3 and 5 showed a pH optimum at 8.5.     

USE OF MALIC ACID AND OTHER QUALITY STABILIZING COMPOUNDS TO ASSURE THE SAFETY OF FRESH-CUT "FUJI" APPLES BY INACTIVATION OF LISTERIA MONOCYTOGENES, SALMONELLA ENTERITIDIS AND ESCHERICHIA COLI O157:H7

The effectiveness of malic acid in combination with physicochemical quality stabilizing compounds to inactivate Listeria monocytogenes, Salmonella Enteritidis and Escherichia coli O157:H7 inoculated in fresh-cut "Fuji" apples packaged in air and stored at 5C was evaluated. Apple pieces were immersed for 1 min in solutions containing 1% w/v N-acetyl-L-cysteine, 1% w/v glutathione and 1% w/v calcium lactate with and without 2.5% w/v D-L malic acid to control apple browning, softening and reduce the populations of pathogenic microorganisms. Fresh-cut apples dipped in each solution were then inoculated with L. monocytogenes, S. Enteritidis or E. coli O157:H7 . The use of malic acid in combination with physicochemical quality stabilizing compounds caused more than 5 log₁₀ cfu/g of L. monocytogenes, S. Enteritidis and E. coli O157:H7 counts. The results obtained in this work pointed out the potential use of malic acid in combination with physicochemical quality stabilizing compounds as a good alternative for safety assurance of fresh-cut apples.

PRACTICAL APPLICATIONS

The use of organic acids such as malic acid, as well as physicochemical quality stabilizing compounds such as N-acetyl-L-cysteine, glutathione and calcium lactate on fresh-cut fruits can benefit the fresh-cut products industry, since they can assure the safety and quality of these products. The main reason for their suitability is their natural origin, thus resulting in fruits that are both attractive and healthy for the consumers who demand fresh-like products.     

INCLUDING CHESTNUTS AND SUGAR BEET PULP IN DIETS FOR PIGS: THE EFFECTS ON THE QUALITY OF PORK MEAT AND THE SENSORY PROPERTIES OF DRY-CURED SAUSAGE (CHORIZO GALLEGO)

This research was aimed at evaluating how the inclusion of dried chestnuts and dried sugar beet pulp in diets for pigs affected the quality of pork meat and the sensory properties of dry-cured sausage ( chorizo gallego ). The meat from pigs that received a diet with chestnuts and sugar beet pulp (CBP) showed lower thiobarbituric acid values and higher water-holding capacity than meat from pigs fed a conventional diet (C). Significant differences were also observed between both batches in color parameters and fatty acid composition of the meat. In the sensory analysis of chorizo, the sausages manufactured with meat from pigs fed the CBP diet were significantly better rated than those with meat from pigs fed a C diet in appearance, odor, flavor, texture and overall score.

PRACTICAL APPLICATIONS

The inclusion of dried chestnuts and dried sugar beet pulp in diets for pigs during the fattening period allowed us to recover some of the ingredients more traditionally used in the feeding of pigs. This inclusion modifies some parameters of the resulting pork meat quality; (it decreases lipid oxidation and increases water-holding capacity and polyunsaturated fatty acid content) and also improves the sensory properties of any dry-cured product made with this pork meat.     

Chemical composition and microbial evaluation of Argentinean Corrientes cheese

The chemical and microbial composition of an artisanal cheese made from raw cow's milk produced and consumed in the province of Corrientes (north-eastern Argentina) was evaluated using standard methods. Corrientes cheese has high moisture content (50–60%), normal protein and fat contents (21–27 and 22–26% respectively), and is low in salt (0.5–2.0% w/w). Microbial counts also varied significantly between samples (colony-forming units per gram ranges covering logs of 5–11), probably due to environmental contamination in the raw material. These results will help produce higher quality Corrientes cheeses with well-defined characteristics.     

CONSUMPTION OF RISKY FOODS AMONG ADULTS AT HIGH RISK FOR SEVERE FOODBORNE DISEASES: ROOM FOR IMPROVED TARGETED PREVENTION MESSAGES

Foodborne disease is of particular concern in populations at risk for severe consequences, including the elderly and persons with immune‐compromising conditions. Using data from the Foodborne Diseases Active Surveillance Network (FoodNet) Population Survey, we examined the association of risky food consumption with gender, age, immune status, income and education. Gender, age and immune status were associated with consumption of risky foods. More males than females ate at least one risky food while persons aged ≥65 years were less likely than those 18–44 to eat risky foods. In the 18–44 group, those with immunosuppressive conditions were more likely to eat risky foods (P < 0.001). In the ≥65 group, those taking immunosuppressive drugs were more likely than healthy persons to eat risky foods (P < 0.001). Our findings suggest that young adults with immune‐compromising conditions and elderly persons who take immunosuppressive drugs report eating more risky foods than their healthy counterparts.     

The Genes Encoding the Transcription Factor yTAFII60, the G4p1 Protein and a Putative Glucose Transporter are Contained in a 12·3 kb DNA Fragment on the Left Arm of Saccharomyces cerevisiae Chromosome VII

We report the nucleotide sequence of a DNA fragment of 12 325 base pairs from the left arm of the Saccharomyces cerevisiae chromosome VII. Inspection of the coding capacity revealed 11 open reading frames (ORFs) longer than 100 amino acids. Five ORFs are significantly homologous to known proteins. The region encoding ORF G2985 corresponds (100%) to the gene encoding the yeast TATA binding protein-associated factor TAF_II60. The G3075 ORF is 47·8% identical to the hypothetical yeast protein YB88. G3080 shows 36·7% identity to the eel calmodulin. G3085 shows 94·9% identity with the published sequence of the quadruplex DNA binding protein G4p1. G3090 reveals 46·7% identity with the probable glucose transport protein yBR1625. The DNA sequence has been submitted to the EMBL data library under Accession Number X97644. © 1997 by John Wiley & Sons, Ltd.     

MICROWAVE HEATING AND γ-IRRADIATION TREATMENT OF RAPESEED (BRASSICA NAPUS)

Rapeseeds were treated with different doses of γ-irradiation and microwave heating of oil extraction. Improvement of the oil extractivity was achieved after microwave treatment while the quality parameters of crude oil were not significantly changed except the total phosphorus content, which was nearly four times higher compared to that of the control. It seems that microwave treatment damages membranes and thus higher amounts of phospholipids may be released into the crude oil. Microwave heating also resulted in a reduction of enzyme activities and lower protein content in buffered seed extracts due to partial protein denaturation. The differences in protein profiles of treated and untreated seeds were also demonstrated by SDS PAGE. The protein denaturation was observed for all types of proteins. γ-irradiation had practically no effect on the oil quality parameters and did not change its yield.     

APPLICATION OF LOW TEMPERATURE HEAT TREATMENTS BEFORE RETORTING IMPROVES THE QUALITY OF CANNED POTATOES

Low temperature heat treatments applied to potatoes (cv Atlantic, Snowden, and Pike) prior to retorting were evaluated for their effect on sloughing in canned potatoes. Blanching in water for 30 min at 60 - 77C before retorting decreased potato breakage, brine turbidity, and brine soluble solids without adversely affecting firmness or color. Low temperature blanching was only effective when potatoes were retorted in CaCl₂ (0.1 %) brine solutions. Sloughing was also decreased by a hot-fill and hold process that utilized brine fill temperatures of 77 − 93C followed by a 30 min hold in CaCl₂ (0.1 %) brine before commercial sterilization. The hot-fill and hold method for control of sloughing in canned potatoes is an improvement over current methods because it eliminates the need for a blanching step and requires only minimal changes in equipment or product flow.     

TRANSIENT PERFORMANCE OF A SYNCHRONOUS DRIVE FOLLOWING A SHORT STATOR CURRENT INTERRUPTION

ABSTRACT

The object of the study is torque and current stress after automatic reswitching of a salient-pole synchronous motor. The three parts of the simulated transient process are: phase-by-phase switching off, operation of the loaded motor isolated from the net and finally the performance after reswitching. The actual load torque as dependent on velocity is taken into account and the pulling into step is checked.