FOR PHYSICOCHEMICAL PARAMETERS Fructose–glucose ratio | Hydroxymethylfurfural | Total reducing sugar | Sucrose | Fiehe’s test | Energy value | Moisture | Diastase activity | Ash | Acidity | Specific gravity at 27 degrees Celsius | Water-insoluble matter | Optical density
Fructose–glucose ratio, % by mass
Requirement: If Fiehe's test is positive and hydroxymethylfurfural (HMF) content is more than 80 milligrams/kilogram, then fructose-to-glucose ratio should be 0.95 minimum as per FSS Rules and more than 1.0 as per Indian Standard.
Fructose/glucose ratio indicates the ability of honey to crystallize. When the fructose/glucose ratio is high, honey remains liquid.
However, because honey contains others sugars (sucrose, maltose, etc.) and insoluble substances (dextrin, colloids, etc.) that can influence the crystallization process, the glucose/water (G/W) ratio is considered more appropriate than the fructose/ glucose(F/G) ratio for the prediction of honey crystallization. Even though honey has less glucose than fructose, it is the glucose that crystallizes when honey granulates because it is less soluble in water than fructose. All the brands meet the minimum requirement mandated by FSSAI. The highest ratio is in Khadi followed by Organica, Dabur and Patanjali.
Hydroxymethylfurfural, or HMF, is often used as an indicator for the quality of honey. It occurs naturally in most honeys; however, high levels of HMF may be the result of inadequate storage, adulteration with sugar additives, or severe heat treatment. Although HMF is not thought to be a harmful substance, food standards in many countries regulate the levels of HMF in honey because it indicates the freshness of honey.
Dabur achieved full score on this parameter. Hitkary, Jeevan Amrit and Organica had high HMF and did not meet the quality requirement limit of 80 mg/kg.
Total reducing sugar
Requirement: 65% minimum as per FSSAI, 70% minimum (special)/65% minimum (Grade A) as per Agmark and Indian Standard
Reducing sugars are capable of reducing other compounds. The most common reducing sugars are glucose and fructose.
Total reducing sugar in Fresh & Pure, Hitkary, Khadi, Reliance and Easy Maxx was found to be less than the required minimum percentage. Dabur performed on top followed by Patanjali.
A key concern about honey quality is possible adulteration with sucrose (just like honey can be adulterated with table sugar, etc.). While sucrose is generally present in small quantities in honey, a high percentage can point towards deliberate adulteration. The Bureau of Indian Standards (BIS) and the Food Safety and Standards Authority of India (FSSAI) have specified that sucrose content in honey should not be more than five per cent by mass. Patanjali performed on top followed by Fresh & Pure, Easy Maxx and Dabur.
Requirement: Should be negative
Fiehe’s test checks if commercial invert sugar has been added to honey for adulteration. As per Indian Standard requirement, if Fiehe’s test is positive and hydroxymethylfurfural content is more than 80 milligrams/kilogram, then fructose-to-glucose ratio should be 1.0 or more. Hitkary, Jeevan Amrit and Organica were found positive in this test. Testing positive in Fiehe’s test also indicates that the honey is ‘over-mature’. When honey is heated for longer duration, it becomes susceptible to testing positive in Fiehe’s test. Honey is heated to kill any yeast that may spoil it. However, it is believed that there is a real danger of honey losing its beneficial properties and actually becoming harmful for consumption if it is over-heated.
Energy value, kcal/100g
Honey contributes a good amount of energy towards our daily requirement.
All the brands performed well on this parameter.
Higher moisture content can lead to undesirable fermentation of the honey during storage. The action of osmotolerant yeasts can result in the formation of ethyl alcohol and carbon dioxide.
Both FSSAI and Agmark have set the permissible limit for moisture at 25 per cent. BIS prescribes that the best-quality honey (Special grade) should not have more than 20 per cent moisture in it. Moisture content for Grade A honey is a maximum 22 per cent by mass. All the tested brands had less than 20 per cent moisture content. Khadi had the least percentage at 14.98.
Diastase activity helps to determine if the honey has been extensively heated during processing. Heating of honey causes the loss of thermolabile, aromatic substances.
All the brands passed in this test. All the brands are within the specified limit on the parameters of ash, acidity, specific gravity (at 27 degrees Celsius), water-insoluble matter, and optical density.