The impact of immersion time in lime solution on antioxidant and antidiabetic properties and consumer evaluation of Sargassum hystrix seaweed tea

Damayanti Rahmatika Pratiwi, Amir Husni

Abstract.

Sargassum hystrix is a brown seaweed that contains bioactive substances, such as antioxidant and antidiabetic compounds, and is used as a functional ingredient in the food industry. They are mostly found in Indonesian waters, growing along rocky shorelines. Since the beverages extracted from seaweed are found to be less preferred by consumers due to the fishy smell, efforts are needed to curtail this problem. Based on this condition, the lime solution immersion method is observed as a suitable approach to reduce the pungent smell. Therefore, this study aims to determine the effect of the immersion time of the lime solution on antioxidant and antidiabetic properties, as well as on consumers’ preference for S. hystrix tea. In this research, the variation of seaweed immersion time at 0, 4, 8, 12, and 16 min, was used in a lime solution of pH 5 at 85°C. Multiple analyses were further carried out on the beverage, including moisture and total phenol content, hedonic teat, and antioxidant property, such as inhibitions of DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (ferric reduction antioxidant power), and α-glucosidase. The results indicated that the immersion time had no effect (p > 0.05) on the water content, although it significantly affected total phenol levels, antioxidant, and antidiabetic activities, as well as the consumer preference for S. hystrix tea (p < 0.05). The best quality was obtained at 16 min, which indicated water and total phenol contents at 3.10 ± 0.33% and 76.81±0.23 mg GAE g-1, with DPPH, FRAP, and α-lucosidase inhibition activities at 53.86±1.27%, 121.82±0.91 µM g-1 , and 52.86±0.89%, respectively. It also showed consumer evaluations for appearance, color, flavor, taste, and overall quality, at 4.39±0.91, 4.33±0.78, 4.08±1.23, 4.25±1.08, and 4.26+0.13, respectively. Furthermore, immersion time in lime solution improved the quality and consumer evaluation of S. hystrix tea. read more

Lecturers of Bachelor in Fish Product Technology (BFPT) again actively participated in the 17th National Seminar (Semnaskan) and 4th International Symposium in Marine and Fisheries Research (ISMFR) held by the Department of Fisheries, Faculty of Agriculture, UGM. National Seminar is an annual agenda while ISMFR is a biannual agenda held in the context of exchanging research results in the field of fisheries and marine affairs. This year, the 17th Semnaskan invited Prof. Dr. Ir. Rokhmin Dahuri, M.S. and Dr. Ir. Bambang Triyatmo as the keynote speaker. read more

The long wait after the ASIIN assessment has finally been answered. We are proudly announcing that Bachelor in Fish Product Technology (BFPT), Departement of Fisheries UGM are awarded ASIIN accreditation for full 5 years. With a successful program accreditation, ASIIN confirms that a study program meets a high-quality standard. The quality of a study program is determined by the formulation of relevant objectives by the applying university itself. The quality is also determined by the success that graduates achieve in their profession. read more

The series of ASIIN (Die Akkreditierungsagentur für Studiengänge der Ingenieurwissenschaften, Informatik, Naturwissenschaften und Mathematik atau Accreditation Agency for Degree Programs in Engineering, Informatics/Computer Science, the Natural Sciences and Mathematics) accreditation activities has reached the final stage with online visitations. The visitation was held on March, 23-25 2021 attended by 7 assessors representatives from University, industry (practitioner), student, and ASIIN office. The on-line visitation was started by the meeting with UGM Rector, accompanied by the vice-rector, director, dean, vice-dean, and task force team. The visitation then continued with a discussion with the program coordinator. On the second and third day, the discussion was done with students, alumni, industries, and teaching staff. read more

The ASIIN accreditation online visitation will be held on March, 23-25 2021. For the best performance, all study programs (included BFPT) together with the Rector, Vice-rector, Director of University Quality Assurance office, Dean and vice-dean of the Faculty of Agriculture, dean and vice-dean of the Faculty of Forestry, University asset staff, and IT staff, held a final coordination meeting. We hope the accreditation process will run smoothly and BFPT is awarded a full 5-year ASIIN accreditation. read more

Dr. Amir and Dr. Sita published new book with tittle “Rumput Laut sebaga Sumber Pangan Kesehatan dan Kosmetik” or Seaweed as food, health and cosmetics source. Published on January 27, 2021.

Indonesian Society for Fish Processing Technology or Masyarakat Pengolahan Hasil Perikanan Indonesia (MPHPI) held the 12th scientific meeting in 2020 by on-line system due to Covid-19 pandemic on September 1-2 2020. In this year BFPT UGM was appointed as the organizing committee.  Held together with Semnaskan UGM (an annual national seminar in fisheries science organized by Department of Fisheries UGM), BFPT successfully invited 4 keynote speaker related to fish processing technology and many researcher from various University and research Institute to disseminate their recent research activities. Dr. Nurfitri Ekantari as the chairman of the committee said that all achievement of this seminar activity could not be separated from the support of all committees and participants. read more

Growth Rate and Histamine Production of Klebsiella sp. CK02 Isolated from Skipjack Tuna Compared with Morganella morganii ATCC 25830 at Various Incubation Temperatures

Aldino Dityanawarman, Indun Dewi Puspita, Susana Endah Ratnawati, Nurfitri Ekantari, and Mark Tamplin

Abstract

One of an important quality parameter in tuna is the level of histamine content. The contamination of histamine in tuna is mainly due to the activity of histidine decarboxylase produced by the bacteria. A rapid growth of histamine producing bacteria is correlated with the practice of temperature abuse during handling. This study aimed to develop predictive growth modeling of two histamine-producing bacteria in the function of temperature. The growth and histamine production of Klebsiella sp. CK02 and Morganella morganii ATCC 25830 at various temperatures were measured in tryptic soy broth histidine (TSBH) and tuna fish infusion broth (TFIB) growth media. Broths were incubated at 4°C and 15°C for 7 days, and at 30°C and 40°C for 24 hours. The Baranyi and Roberts model was used with DMFit to determine primary growth kinectics, and the Ratkowsky square root model to describe bacterial growth rate as a function of temperature. Histamine production was enumerated by the apparent yield factor (pYhis/ CFU) value. Growth rate increased with temperature, with a maximum rate at 40°C for Klebsiella sp. CK02 (0.740 log CFU/h) and M. morganii (0.578 log CFU/h). The Tmin for Klebsiella sp. CK02 in TFIB was -8.9°C, indicating better survival in low storage temperature, compare to M. morganii ATCC 25830. In addition, Klebsiella sp. CK02 produced a lower pYhis/CFU at 15 and 30°C compared to M. morganii ATCC 25830.
Keywords: growth rate, temperature, histamine, Klebsiella sp. CK02, M. morganii ATCC 25830 read more

Department of Fisheries held a 56^th anniversary on September 1st 2019 by organized an event for Department member including lecturer, staff and students. Starts with walked around the campus, the event continued with door prized draw and lunch with all fish menu.

As an annual event, this year on 22-23 August 2019, Department of Fisheries again Kenal Perikanan (introducing fisheries sector to new students) by visited Pekalongan City in Central Java. Students were introduced to brackish water aquaculture (shrimp commodity), fisheries home industries (nugget, otak-otak etc.), fish canning industry and fisheries auction spot at Pekalongan fishery port.