We Japanese people can get many foods whenever we would like to have some foods. But we have distrust of food safety. When we feel some abnormal flavor from foods, we doubt food safety in case of no problem. We comprehend this flavor the important problem in food business. Such a flavor is called off-flavor in foods. We introduce some cases of off-flavor in foods and the methods of solution these problems.
There are three types of off-flavor generating factor. ①off-flavor at the time of food production ②off-flavor at the time of food distribution ③off-flavor at the time of food preservation
Off-flavor problem comes to the surface when the consumer appeals the abnormal flavor in food. So food supplier should conclude the origin of this off-flavor precisely. After they have organoleptic evaluation for this off-flavor, analysis of this flavor should be carried out with GC-MS method. Case by case food supplier need to decide food sale discontinuance or food collection.
Such an off-flavor problem should be discussed on common ground, because food quality control is not secret different from food development. We established Food Off-flavor Study Group in 2012. We expect many people joining this party.
Collagen and elastin are extracellular matrix protein and their hydrolysates prepared form marine materials are used as functional food ingredients. The beneficial effects on human skin and joint conditions after oral ingestion have been reported. To elucidate the mechanisms for the beneficial effects, we attempted to detect the food-derived peptides in human blood after oral ingestion of the hydrolysate. Pro-Hyp and Pro-Gly were identified as major food-derived peptides in human blood after ingestion of collagen and elastin hydrolysate respectively. We have demonstrated that the bioactivities of those peptides on human skin fibroblast. Thus, it has been speculated that the food-derived peptides in human blood may play significant role in the beneficial effect after the ingestion of the hydrolysates. We also found the dose-dependent increase of food-derived collagen peptides in human blood that may causes individual differences on the beneficial effects. For effective utilization and value addition of marine products, it is important to understand the more detailed mechanism for the beneficial effects and potential bioactivity of marine food-derived peptides.
Total global capture fishery and aquaculture production have been increasing annually, reaching approximately 200 million tonnes. While capture fishery production has been relatively static since the late 1980s, aquaculture production has been increasing markedly, comprising more than 50% of total production in recent years. Although Anchoveta has maintained the greatest share of fish production, Alaska pollock is now the largest fishery.
Alaska pollock is caught in the North Pacific Ocean and is strictly maintained in accordance with the total allowable catch system. This resource in the Northeast Pacific Ocean is certified by the Marine Stewardship Council.
Alaska pollock is known to decline quickly in freshness and to have poor stability in frozen storage. With current advancements in processing technology, fish are processed in various ways such as into surimi, fillet blocks, and fishmeal, and the roe are also utilized. Continued efforts to manage fish resources appropriately are essential in order to resolve food shortage problems.
The purpose of this study was to determine the effects of a high-fat/high-sucrose diet on lipid metabolism in rats kept in constant darkness. Four-week-old rats (F344 strain) were kept in constant darkness (D) or normal lighting (12-h light-dark cycle) for 4 weeks. The experimental diets were the AIN-93G diet as a control (C) and high-fat/high-sucrose diet (H). Thirty rats were divided into the following three groups: normal lighting and the control diet (C group), normal lighting and the high-fat/high-sucrose diet (H group), and constant darkness and the high-fat/high-sucrose diet (DH group). Five rats in each group were dissected in the fourth and seventh weeks of experimental treatment. Body weight gain in the H group was greater than that in the DH group in the fourth week and greater than that in the DH and C groups in the seventh week. Liver weight (g/100 g BW) in the DH group was lower than that in the H group in both the fourth and seventh weeks. The weights of perirenal and epididymal fats (g/100 g BW) in the H group and DH group were higher than those in the C group. In addition, perirenal fat weight in the DH group tended to be higher than that in the H group. There were no differences among the three groups in serum total cholesterol concentration in the fourth and seventh weeks. HDL cholesterol concentration in the DH group was lower than that in the C and H groups in the seventh week. The expression of Apo-a1 mRNA in the liver did not differ significantly among the three groups. However, the expression of Abc a-1 in the liver in the DH group was lower than that in the C group and tended to be lower than that in the H group.
From the above results, it was suggested that the low serum HDL cholesterol concentration in the rats kept in constant darkness and fed a high-fat/high-sucrose diet was induced by the low expression of Abc a-1 mRNA in the liver.
This research aims to clarify the characteristics of human behavior while eating meals in co-eating and solitary eating situations. To manipulate eating situations, we observed participants' behaviors (N = 6) under two different experimental settings: a solitary eating condition, in which participants had their meals alone while watching television or using their cellphone, and a co-eating condition, in which participants ate their meals in the course of dyadic conversation with friends. We assessed the participants’ gaze behaviors and eating actions during the meal and compared these between the two eating situations statistically. The results demonstrate that 1) participants in the co-eating condition glanced longer at their own meal compared to participants in the solitary eating condition, 2) participants in the solitary eating condition often stopped their other eating actions while chewing food, and 3) participants in the co-eating condition frequently gathered meal portions using a spoon while looking at their meal. These results suggest that participants in the solitary eating condition enjoyed their meal while watching television or using their cellphone in an informal atmosphere. Meanwhile, participants in the co-eating condition used their meals to coordinate their interactive behaviors with a co-eater. The social functions of co-eating are discussed from a human behavior analysis perspective.
[Objective] The aim of this study is to provide a more suitable method for assessing nutrient contents to aid nutritional assessment and menu preparation.
[Methods] Vegetable products and animal products in the "Standard Tables of Food Composition Japan -2010-" were categorized by food group, method of cooking, and other factors. The rate of component change (weight, energy, general components, fatty acids, cholesterol, dietary fiber, nitrate ion) in each group according to various cooking by methods was examined.
[Results] The rates of component change through cooking in vegetable products could be divided into 32 groups. The rates of component change through cooking in animal products could be divided into 17 groups. Differences in the rates of component change through cooking were apparent between the groups, even within the same food group.
[Conclusions] The rates of component (weight, energy, general components, fatty acids, cholesterol, dietary fiber, nitrate ion) change in 29 groups were found to be useful for therapeutic diets. The evaluated rates of component change through cooking can be used for estimating the amount of nutritional components that remain after cooking. Therefore it is possible to compute the amount of nutritional components for cooked food with no nutritional component value. This improves the accuracy for calculating the nutritional value in nutritional assessment and menu preparation.
Previous research has suggested a possible relationship between stress and the taste threshold. For example, it has been reported that chronic mental fatigue accompanied by dejection, or discomfort, greatly affected the threshold for salt taste. However, there are only a few studies on the effects of acute stress on taste. Therefore, the present study examined the influence of acute mental stress on the threshold for tasting saltiness. Participants in the study were healthy female university students (N = 57, Mean age: 21.8 ± 0.8 years). They were randomly separated into a stress group and a control group. Then, stress was induced in the stress group by an irregular training experience. Following stress induction, participants sat for 20 minutes and rested. Following this the taste for saltiness was compared in the two groups. All the participants were also assessed for feelings of anxiety and feelings of Pleasantness. Results indicated that the stress group had a significantly higher saltiness score than the control group. In addition, the stress group had less pleasant feeling after stress stimulation, indicating that acute mental stress was successfully induced in the stress group. These results suggest that the threshold for saltiness is reduced under conditions of acute mental stress.
In recent years, the Japanese population has been rapidly aging. We examined the effectiveness of a nutritional improvement program designed to enable elderly individuals to live independently in their community.
We conducted pre- and post-assessments on 203 community-living elderly individuals who participated in a nutritional improvement program. We divided the participants into a low-scoring group and the other group based on their "dietary status score" from a pre-assessment.
The results from this study are summarized as follows:
1) Men and women in the low-scoring group had a better "dietary status score" after the nutritional improvement program. Moreover, the "daily consumption of a dish cooked in oil" became more prevalent among the men and women. The "dietary habits score (enjoyment of meals, and favorability of current dietary habits)" of the men in the low-scoring group also improved.
2) TUG (Timed Up and Go Test) improved among the men and women in the low-scoring group, and women in the other group.
The nutritional improvement program was shown to be effective for participants who had a low “dietary status score”, therefore, it may contribute to preventive care.
Non-degassed roasted coffee bean extracts contain large quantity of volatile compounds, compared with degassed roasted coffee bean extracts. In this study, we investigated the effect of non-degassed roasted coffee bean extracts or degassed roasted coffee bean extracts, on lipid metabolism in mice. Male C57BL/6J mice, fed a high fat diet, were administered with non-degassed, or degassed roasted coffee bean extracts for 8 weeks. At the end of the administration period, in non-degassed roasted coffee bean extracts group, plasma triglyceride elevation was suppressed. On the other hand, in degassed roasted coffee bean extracts group, the effect was not observed. On hepatic triglyceride level, non-degassed roasted coffee bean extracts showed a significant suppressive effect. Moreover, the 33 volatile compounds mixture which were decreased by degassing, suppressed plasma triglyceride elevation. These results suggested that volatile compounds, decreased by degassing, might involve the suppressive effects on plasma and hepatic triglyceride elevation in mice.
Edible wild mushrooms collected in Nagano Prefecture were immersed in water for 1,440 min. The eluted radioactive cesium (Cs) was detected by an auto radiography method (ARG). The eluted potassium (K) was detected by a total reflection X-ray fluorescence analysis method. The mushrooms were divided into the following 4 groups: MW-g; 500 W microwave for 1 minute, Dry-g; 60 degrees centigrade for 12 hours, Frozen-g, -20 degrees centigrade for 12 hours and Raw-g; no treatment. Each treated mushroom was placed in 50 ml of pure water, immersion fluid was sampled 1.0 ml after 10, 30, 60, 180, 360 and 1,440 minutes of immersion, then filtered through a 0.45 μm pore size filter.
The dried immersion samples were imaged by ARG. It was suggested that radioactive Cs was eluted into the water from each of the treated mushrooms. The photo-stimulated luminescence density (PSL) of the Raw-g was lower than these of the treated groups (MW-g, Dry-g and Frozen-g) at each time point. Also, the K concentration of the Raw-g was lower than those of the treated groups. It was suggested that Cs and K are easily eluted due to destruction of the mycelium cells. The elution curves, which were created as a percentage of each concentration of the PSL and K, were similar. It was postulated that the elution mechanisms of the radioactive Cs and K are similar.
Furthermore, the elution rate of 137Cs was calculated based on its radioactivity, which was measured by a high-purity germanium (HPGe) semiconductor detector before and after the immersion of each mushroom. The elution rate of 137Cs was > 80% for the treated mushrooms. On the other hand, the elution rates of K for the control shiitake and mushrooms which were calculated using the value of the K concentration of the raw shiitake in the 7th revised Japan food composition table were < 20%. It was postulated that the radioactive Cs, which was easily removed, had accumulated in the mushrooms as an ionic species.
We examined the effects on blood pressure and lipid metabolism of long-term administration of Mugwort rice cake. In order to observe the effect of each of its constituents, rice cake samples were the following three types: mugwort (Artemisia indica Willd. var. orientalis Hara) brown sugar rice cake, mugwort white sugar rice cake, and brown sugar rice cake. Spontaneously hypertensive rats (SHRs) of five weeks of age were divided into four groups. The control group fed on the standard purified diet AIN-93G, while the experimental groups were given diets containing 10% freeze-dried samples of each type of rice cake for 15 weeks. In terms of the results, the systolic blood pressure levels were significantly decreased at 9 weeks of age in mugwort brown sugar group and mugwort white sugar group, at 14 weeks of age in brown sugar group. In terms of lipid metabolism, the SHRs fed mugwort brown sugar exhibited significantly decreased serum levels of triglyceride. In addition, the mugwort white sugar group showed a significant decrease in liver total cholesterol. These results suggest that daily feeding on mugwort rice cake showed antihypertensive effects and improved lipid metabolism.
Tokushima prefecture is the second largest producer of lotus roots in Japan, with an annual harvest of approximately 8,000 tons. In the present study, we determined the contents of amino acids in the flesh, joint, and peel of lotus roots of two cultivars, "Bicchu" and "Lotus", grown in Tokushima prefecture. Asparagine, glutamine, arginine and alanine accounted for more than 60％ of the total amino acids in the flesh of "Bicchu" and "Lotus" roots, while glutamine comprised around 5％ of the total amino acids in their joint and peel. When comparing the cultivars, "Lotus" roots contained the almost same level of γ-aminobutyric acid （GABA） than "Bicchu" roots, with a preferential distribution in the flesh. These results suggest the potential applications of the unused parts (joint and skin) of lotus roots grown in Tokushima prefecture as an ingredient in processed food products.